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- Mass spectrometry (2)
- Ribosome (2)
- Stalling (2)
- TmRNA (2)
- Total synthesis (2)
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- Trans-translation (2)
- 2-deoxystreptamine (1)
- 5 (1)
- 5'-bis-ureido deoxyadenosine (1)
- Acutumine (1)
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- Air quality standards (1)
- Alkaloid (1)
- Aminoglycoside (1)
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- Anion-exchange chromatography (1)
- Anti-cancer agents (1)
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- Asymmetric aldol reaction (1)
- Bag (1)
- Beta-Hydroxy alpha-amino acids (1)
- Bioanalysis (1)
- Biocompatibility (1)
- CCT (1)
- Cadherin (1)
- Calcium (1)
- Capillary flow porometry (1)
- Capillary size exclusion chromatography (1)
- Cell-cell adhesion (1)
- Celogentin C (1)
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Articles 1 - 22 of 22
Full-Text Articles in Physical Sciences and Mathematics
Progress Toward The Total Synthesis Of Lyconadin A, Yu Zhang
Progress Toward The Total Synthesis Of Lyconadin A, Yu Zhang
Theses and Dissertations
Lyconadin A is a pentacyclic Lycopodium alkaloid isolated from the club moss Lycopodium complanatum with antitumor properties. We have developed a novel 7-exo/6-exo acyl radical cascade cyclization as a method of making the bicyclo[5.4.0]undecane ring system of lyconadin A. The model products are trans-fused ring systems, while a cis-fused ring system is needed in lyconadin A. We have discovered a method to convert the trans-fused model cascade cyclization product into the desired cis isomer. Based on Donohoe's pyridone synthesis, we developed a method for the construction of 5-alkyl and 3,5-dialkyl-6-carbomethoxy-2-pyridones, the former of which …
Synthesis And Evaluation Of N6,5'-Bis-Ureido-5'-Amino-5'-Deoxyadenosine Derivatives: Novel Nucleosides With Antiproliferative And Protein Kinase Binding Activities, Marcelio Oliveira
Synthesis And Evaluation Of N6,5'-Bis-Ureido-5'-Amino-5'-Deoxyadenosine Derivatives: Novel Nucleosides With Antiproliferative And Protein Kinase Binding Activities, Marcelio Oliveira
Theses and Dissertations
A new series of N6,5'-bis-ureido-5'-amino-5'-deoxyadenosine derivatives was prepared and evaluated for anticancer activities using the NCI 60 panel of human cancers. Certain of the derivatives showed promising activities (low micromolar GI50's) against several of the representative cancers. These included cell lines from the following general cell types in the NCI 60: Leukemia, Breast, Central Nervous System, Non-Small Cell Lung, Ovarian, Prostate, Renal, and Colon cancers. Select compounds were also screened for their affinities for protein kinases. The synthesis of the compounds was straightforward and involved N6 acylation with arylisocyanates, preceded by activation and nucleophilic substitution of the 5'-position to give …
Pore Size Characterization Of Monolithic Capillary Columns Using Capillary Flow Porometry, Yan Fang
Pore Size Characterization Of Monolithic Capillary Columns Using Capillary Flow Porometry, Yan Fang
Theses and Dissertations
A simple capillary flow porometer (CFP) was assembled for pore structure characterization of monolithic capillary liquid chromatography columns based on ASTM standard F316-86. Determination of differential pressures and flow rates through dry and wet samples provided the necessary information to determine the through-pore throat diameter, bubble point pore diameter, mean flow pore diameter, and pore distribution. Unlike measurements in bulk using traditional techniques to provide indirect information about the pore properties of monolithic columns, monoliths can be characterized in their original chromatographic forms with this system. The performance of the new CFP was first evaluated by characterizing the pore size …
Gas Phase Chiral Recognition, Characterization Of Porous Polymer Monolith Nanospray Ionization, And The Negative Mode Crafti Method Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Nannan Fang
Theses and Dissertations
Our group has been studying chiral recognition in gas phase using mass spectrometry for more than 10 years. We are interested in gas phase studies of fundamental interactions because the gas phase avoids complications and masking effects that may arise upon solvation. Therefore, the results of gas phase experiments can be directly compared with those of high-level computational studies. In chapter 2, I studied the roles of hydrogen bonding and pi stacking in gas phase chiral recognition between aromatic crown molecules and aromatic amines. High affinity between host and guest doesn't necessarily result in better recognition. If the affinity is …
Total Synthesis Of (-)-Acutumine, Fang Li
Total Synthesis Of (-)-Acutumine, Fang Li
Theses and Dissertations
Acutumine is a tetracyclic alkaloid isolated from the Asian vine Menispermum dauricum with selective T-cell cytotoxicity and antiamnestic properties. We have developed a total synthetic route to this congested alkaloid, during which we also found a novel, stereoselective radical-crossover reaction that combines an intramolecular radical conjugate addition with a subsequent enolate hydroxylation. Key features of this synthesis also include a reagent-controlled diastereoselective ketone allylation, an anionic oxy-Cope rearrangement to form a congested quaternary sterocenter, a pyridine-mediated selective ozonolysis, and a Lewis acid promoted Michael-type cyclization.
Development Of Biocompatible Polymer Monoliths For The Analysis Of Proteins And Peptides, Yun Li
Development Of Biocompatible Polymer Monoliths For The Analysis Of Proteins And Peptides, Yun Li
Theses and Dissertations
Biocompatibility is an important issue for the development of chromatographic stationary phases for the analysis of biomolecules (including proteins and peptides). A biocompatible stationary phase material is a material that resists nonspecific adsorption of biomolecules and does not interact with them in a way that would alter or destroy their structures or biochemical functions. The monolithic column format is a good alternative to typical spherical particle packed columns for capillary liquid chromatography of biomacromolecules. Several novel anion-exchange polymer monoliths for the analysis of proteins were synthesized for improved biocompatibility. Two novel polymeric monoliths were prepared in a single step by …
Real-Time Virus Analysis Via Image Charge Detection Surface Induced Dissociation Tandem Mass Spectrometry, Seth T. Call
Real-Time Virus Analysis Via Image Charge Detection Surface Induced Dissociation Tandem Mass Spectrometry, Seth T. Call
Theses and Dissertations
This thesis reports on the development of a novel mass spectrometer combining image charge detection with surface induced dissociation for real-time analysis of intact viruses. Protonated viruses produced using electrospray are accelerated and subsequently impact on a solid surface. Capsid peptides released during the impact are analyzed using time-of-flight mass spectrometry. Image charge detection is used to measure the mass and charge states of structurally intact, electrosprayed viruses prior to impact. Since virus capsids are composed of loosely-bound proteins, collision of viruses with surfaces at moderate impact energies could release intact proteins. The masses and numbers of different protein types …
Design And Characterization Of A Human Exposure Chamber And Inversion Episodes In Salt Lake City, Utah In January/February Of 2009, Roman Yuri Kuprov
Design And Characterization Of A Human Exposure Chamber And Inversion Episodes In Salt Lake City, Utah In January/February Of 2009, Roman Yuri Kuprov
Theses and Dissertations
Research on health effects of particulate matter (PM) has been a very active area in the last two decades. One plausible mechanism by which exposure to PM affects human health includes modification of autonomic endothelium function. Decreased endothelium activity causes heightened risks of cardiovascular disease. A human exposure chamber designed to conduct experiments to quantify diminished function of endothelium from short term exposure to PM is described. The chamber consists of two stages for containment and pre-treatment of PM and exposure of human subjects. Concentrations of CO, CO2, NO, NO2, O3, and PM2.5, are monitored and controlled in the exposure …
A Top-Down Proteomic Approach For The Discovery Of Novel Serum Biomarkers Of Pregnancy-Related Disease, Karen Merrell
A Top-Down Proteomic Approach For The Discovery Of Novel Serum Biomarkers Of Pregnancy-Related Disease, Karen Merrell
Theses and Dissertations
The serum fraction of blood is an ideal material in which to search for novel biomarkers for disease. It is easily obtained through relatively non-invasive means, routinely collected, and a rich treasure-trove of information about the health of an individual. Cells react to signal molecules, take up nutrients, and release waste products, fragments that are the result of proteolysis, and other molecules out into the bloodstream. If these components are unique to the cells in question, that part of the complex mixture that is the blood stream can potentially characterize the health of the tissue or organ those cells are …
Ion Transport Behaviors Upstream And Downstream From The Sampling Cone Of An Inductively Coupled Plasma Mass Spectrometer, Haibin Ma
Theses and Dissertations
Inductively coupled plasma - mass spectrometry (ICP-MS) is the technique of choice worldwide for trace elemental determinations because of its excellent ionization ability, low detection limits and fast analysis speeds. However, the ICP-MS still suffers from some disadvantages, such as spectral overlap and severe matrix effects. Matrix effects or interferences, partly arise from changes in the analyte transmission through the interfacial region between the ICP and mass spectrometer with changes in sample matrix. Better understanding of the transmission behaviors of analyte through the sampling and skimmer cones will provide the insights needed to alleviate matrix interferences and to improve the …
Relaxation Of Vibrationally Excited Trifluorobenzene And Tetrafluorobenzene By Collisions With Carbon Dioxide, Alan M. Johnson
Relaxation Of Vibrationally Excited Trifluorobenzene And Tetrafluorobenzene By Collisions With Carbon Dioxide, Alan M. Johnson
Theses and Dissertations
An investigation into the relaxation of highly vibrationally excited trifluorobenzene and tetrafluorobenzene following collisions with carbon dioxide was performed using diode laser transient absorption spectroscopy. A 248 nm excimer laser prepared the vibrationally hot (E'~41,000 cm-1) fluorobenzene molecules. Large amounts of translational and rotational energy are transferred through collisions between the hot donor molecule and CO2. Rate constants and collisional probabilities were calculated by probing the high J states (J=58~80) of CO2 in the vibrational ground state, 0000, with measurements taken 1 µsec, ¼ the mean gas collision time, following each excimer laser pulse. The energy transfer probability distribution function, …
The Role Of Smpb In The Early Stages Of Trans-Translation, Deanna June Cazier
The Role Of Smpb In The Early Stages Of Trans-Translation, Deanna June Cazier
Theses and Dissertations
Ribosomes stall on defective messenger RNA transcripts in eubacteria. Without a mechanism to release stalled ribosomes, these cells would die. Transfer-messenger RNA (tmRNA) and small protein B (SmpB) reactivate stalled ribosomes in a process known as trans-translation. Together, tmRNA and SmpB mimic alanyl-tRNA, entering the A site of stalled ribosomes and accepting transfer of the stalled polypeptide. A portion of tmRNA is then positioned as a template for the ribosome to resume translating. The tmRNA open reading frame encodes a proteolysis tag to mark the aberrant polypeptide for degradation and a stop codon to release the ribosome. How are tmRNA …
Novel Cinchona Alkoloid Derived Ammonium Salts As Phase-Transfer Catalysts For The Asymmetric Synthesis Of Beta-Hydroxy Alpha-Amino Acids Via Aldol Reactions And Total Synthesis Of Celogentin C., Bing Ma
Theses and Dissertations
Project I. Cinchona alkaloid-derived quaternary ammonium salts have been successfully used as phase-transfer catalysts, particularly in asymmetric alkylations. Our group applied this type of catalyst in the synthesis of β-hydroxy α-amino acids via aldol reactions and discovered that the Park-Jew catalyst afforded good yields and good enantiomeric excess of the syn diasteromers, but negligible diastereoselectivity. This project was therefore focused on the synthesis of novel cinchonidine-derived catalysts with the Park-Jew catalyst as the lead structure. The C3 position of cinchonidine nucleus was modified to achieve dimers and catalysts possessing electron-deficient alkyne and alkene moieties. Synthesized catalysts were tested in the …
Genetic Analysis Of Ribosome Stalling And Rescue, Douglas Ray Tanner
Genetic Analysis Of Ribosome Stalling And Rescue, Douglas Ray Tanner
Theses and Dissertations
In eubacteria, ribosome stalling on broken messenger RNA transcripts can lead to cell death. The trans-translation quality control mechanism rescues many of these stalled ribosomes. In this process, tmRNA enters stalled ribosomes by mimicking a transfer RNA, accepting the stalled nascent peptide. The ribosome then releases the broken mRNA and resumes translation on a coding region within tmRNA itself. Translation of tmRNA marks the nascent peptide for destruction by the addition of a short proteolysis tag and the ribosome is released at a stop codon within the tmRNA open reading frame. An intriguing aspect of trans-translation is that …
Synthesis And Evaluation Of Stimulatory Properties Of Glycolipids For Natural Killer T Cells, Xiangtian Long
Synthesis And Evaluation Of Stimulatory Properties Of Glycolipids For Natural Killer T Cells, Xiangtian Long
Theses and Dissertations
Natural killer T cells (NKT cells) are a subset of T cells. They regulate a wide range of diseases including infection, tumor growth, and autoimmune diseases, through recognizing glycolipid antigens in the context of CD1d. An understanding of the scope of glycolipid antigens would facilitate use of this cell type in controlling immune responses. Till today, a lysosomal glycolipid, isoglobotrihexosylceramide (iGb3), is the only natural glycolipid that has been found to be recognized by both human and mouse NKT cells. To elucidate the molecular basis of this specific recognition, iGb3 variants were designed and prepared: i) replacement of the C26 …
Ionic Selectivity In L-Type Calcium Channels By Electrostatics And Hard-Core Repulsion, Dezso Boda, Douglas Henderson, Monika Valisko, Bob Eisenberg, Dirk Gillespie
Ionic Selectivity In L-Type Calcium Channels By Electrostatics And Hard-Core Repulsion, Dezso Boda, Douglas Henderson, Monika Valisko, Bob Eisenberg, Dirk Gillespie
Faculty Publications
A physical model of selective "ion binding" in the L-type calcium channel is constructed, and consequences of the model are compared with experimental data. This reduced model treats only ions and the carboxylate oxygens of the EEEE locus explicitly and restricts interactions to hard-core repulsion and ion–ion and ion–dielectric electrostatic forces. The structural atoms provide a flexible environment for passing cations, thus resulting in a self-organized induced-fit model of the selectivity filter. Experimental conditions involving binary mixtures of alkali and/or alkaline earth metal ions are computed using equilibrium Monte Carlo simulations in the grand canonical ensemble. The model pore rejects …
Synthesis Of 2,4,5-Triaminocyclohexane Carboxylic Acid As A Novel 2-Deoxystreptamine Mimetic, Sarah Elizabeth Roberts
Synthesis Of 2,4,5-Triaminocyclohexane Carboxylic Acid As A Novel 2-Deoxystreptamine Mimetic, Sarah Elizabeth Roberts
Theses and Dissertations
RNAs have become increasingly recognized as possible drug targets due to their involvement in important biochemical functions, as well as their unique but well-defined structures. Recently published crystal structures depict the binding of a series of aminoglycosides- or more specifically- 2-deoxystretamine (2-DOS), the most preserved central scaffold of aminoglycosides, to a conserved 5'-GU-3'region on their target RNAs. A novel unnatural γ-amino acid, 1, has been synthesized using 2-deoxystreptamine as a template through structure-based rational design. The unnatural amino acid has been designed to replace a glycosidic linkage with an amide bond, which may limit the promiscuous binding characteristics of aminoglycosides …
Role Of Molecular Chaperones In G Protein B5-Regulator Of G Protein Signaling Dimer Assembly And G Protein By Dimer Specificity, Alyson Cerny Howlett
Role Of Molecular Chaperones In G Protein B5-Regulator Of G Protein Signaling Dimer Assembly And G Protein By Dimer Specificity, Alyson Cerny Howlett
Theses and Dissertations
In order for G protein signaling to occur, the G protein heterotrimer must be assembled from its nascent polypeptides. The most difficult step in this process is the formation of the Gβγ dimer from the free subunits since both are unstable in the absence of the other. Recent studies have shown that phosducin-like protein (PhLP1) works as a co-chaperone with the cytosolic chaperonin complex (CCT) to fold Gβ and mediate its interaction with Gγ. However, these studies did not address questions concerning the scope of PhLP1 and CCT-mediated Gβγ assembly, which are important questions given that there are four Gβs …
Functionalization, Characterization, And Applications Of Diamond Particles, Modification Of Planar Silicon, And Chemoetrics Analysis Of Ms Data, Li Yang
Theses and Dissertations
In spite of the stablility (lack of reactivity) of diamond powder, I have developed a method for tethering alkyl chains and polymers to deuterium/hydrogen-terminated diamond. One method is through ether linkages via thermolysis of di-tert-amyl peroxide (DTAP). This reaction with DTAP has also been applied to grow polymers on the diamond surface. The other method is atom transfer radical polymerization (ATRP), which was applied to grow polystyrene at the surface of diamond. Both polystyrene-modified diamond and sulfonated polystyrene-modified diamond can be prepared by either method, and can be used for solid phase extraction. Diamond stationary phases are stable under basic …
The First Attachment And Post-Functionalization Of Polybutadiene And Thio-Click Functionalized Polybutadiene On H-Terminated Si(111), Todd Devere Wickard
The First Attachment And Post-Functionalization Of Polybutadiene And Thio-Click Functionalized Polybutadiene On H-Terminated Si(111), Todd Devere Wickard
Theses and Dissertations
I report the attachment of polymers with pendant vinyl groups to hydrogen-terminated silicon(111) (Si(111)-H) under mild conditions. 1,2-addition polybutadiene (Mw 3200-3500) was attached to Si(111)-H at room temperature with visible light. I also report the partial functionalization, in solution, of 1,2-addition polybutadiene with various thiols using thiol-click chemistry. These compounds bind to Si(111)-H via visible light activation. The partially functionalized polybutadienes allow further functionalization at the surface through unreacted carbon-carbon double bonds. Surfaces were characterized with contact angle goniometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and atomic force microscopy (AFM).
Polymer Microfluidic Devices For Bioanalysis, Xuefei Sun
Polymer Microfluidic Devices For Bioanalysis, Xuefei Sun
Theses and Dissertations
Polymeric microchips have received increasing attention in chemical analysis because polymers have attractive properties, such as low cost, ease of fabrication, biocompatibility and high flexibility. However, commercial polymers usually exhibit analyte adsorption on their surfaces, which can interfere with microfluidic transport in, for example, chemical separations such as chromatography or electrophoresis. Usually, surface modification is required to eliminate this problem. To perform stable and durable surface modification, a new polymer, poly(methyl methacrylate-co-glycidyl methacrylate) (PGMAMMA) was prepared for microchip fabrication, which provides epoxy groups on the surface. Whole surface atom transfer radical polymerization (ATRP) and in-channel ATRP approaches were employed to …
Using A Mathematical Model Of Cadherin-Based Adhesion To Understand The Function Of The Actin Cytoskeleton, J. C. Dallon, Elijah Newren, Marc Hansen
Using A Mathematical Model Of Cadherin-Based Adhesion To Understand The Function Of The Actin Cytoskeleton, J. C. Dallon, Elijah Newren, Marc Hansen
Faculty Publications
The actin cytoskeleton plays a role in cell-cell adhesion but its specific function is not clear. Actin might anchor cadherins or drive membrane protrusions in order to facilitate cell-cell adhesion. Using a mathematical model of the forces involved in cadherin-based adhesion we investigate its possible functions. The immersed boundary method is used to model the cell membrane and cortex with cadherin binding forces added as linear springs. The simulations indicate that cells in suspension can develop normal cell-cell contacts without actin-based cadherin anchoring or membrane protrusions. The cadherins can be fixed in the membrane or free to move and the …