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Dna Polymerase Alpha: The Eukaryotic Lagging Strand Polymerase, Scott Kirkness Davey
Dna Polymerase Alpha: The Eukaryotic Lagging Strand Polymerase, Scott Kirkness Davey
Digitized Theses
This work is an in vitro study of the DNA polymerase {dollar}\alpha{dollar}-DNA primase complex, which is thought to synthesize DNA on the lagging strand at replication forks. We have purified the complex, and studied two aspects of RNA primed DNA synthesis catalyzed by this enzyme complex in vitro.;DNA polymerase {dollar}\alpha{dollar} has been purified from cultured mouse Ehrlich ascites tumour cells, by classical purification methods, to a specific activity of 60 000 units/mg total protein. The purified DNA polymerase {dollar}\alpha{dollar} complex has four subunits, 182, 70, 55, and 47kDa. A 3{dollar}\sp\prime\to 5\sp\prime{dollar} exonuclease activity, detected after treatment of the complex with …
Spectroscopic Studies Of Mercury And Cadmium Binding To The Protein Metallothionein, Wuhua Lu
Spectroscopic Studies Of Mercury And Cadmium Binding To The Protein Metallothionein, Wuhua Lu
Digitized Theses
Metallothioneins (MT) are a class of low molecular weight, cysteine rich proteins, which bind a wide range of metals both in vivo and in vitro. This protein has become the subject of intensive interest in many branches of the life sciences over the past two decades.;In this thesis, the manner in which mercury and cadmium bind to metallothionein has been studied using the techniques of circular dichroism (CD), magnetic circular dichroism (MCD), UV-visible absorption, and X-ray near edge absorption structure (XANES) spectroscopy.;At neutral pH, the Hg{dollar}\sb7{dollar}-MT and Hg{dollar}\sb4{dollar}-{dollar}\alpha{dollar} MT species formed from metal-free MT (apo-MT), or Zn-MT adopt a mercury-thiolate …
The Recovery Of Underlying Lifetime Distributions From Fluorescence Decay Data, Brian Douglas Wagner
The Recovery Of Underlying Lifetime Distributions From Fluorescence Decay Data, Brian Douglas Wagner
Digitized Theses
In this thesis, two methods for recovering underlying lifetime distributions from single photon counting fluorescence decay data are described, namely the Exponential Series Method (ESM) and the Maximum Entropy Method (MEM). Extensive testing of these two methods is performed, using both real and simulated decay curves, in order to establish their abilities and limitations, especially with respect to the resolution of discrete lifetimes, the accurate recovery of broad distribution shapes, and the ability to distinguish conclusively between these two cases. The effect of data precision, relative separation in {dollar}\tau{dollar}-space of the discrete lifetimes or distributions, and experimental noise on the …
Aspects Of Lipid Metabolism During Rat L(6) Skeletal Myogenesis, Victor S. Sauro
Aspects Of Lipid Metabolism During Rat L(6) Skeletal Myogenesis, Victor S. Sauro
Digitized Theses
The primary objective of this study was to determine the regulating factor(s) responsible for the coordinate changes in lipid metabolism observed as L{dollar}\sb{lcub}6{rcub}{dollar} myoblasts switch from predominantly triacylglycerol (TAG)-synthesizing cells to primarily phospholipid-synthesizing cells during fusion into myotubes (ie. skeletal myogenesis). Myoblasts, but not myotubes, showed a dramatic accumulation of TAG in fatty acid-supplemented growth medium. Both fatty acid oxidation and phospholipid synthesis increased significantly during skeletal myogenesis. Pulse-chase studies showed products of TAG degradation to be used for phospholipid synthesis (prior to oxidation), which resulted in a 4-fold increase in phospholipid content during skeletal myogenesis. A 2-fold increase in …
Homo- And Heteronuclear Clusters Of Platinum And Gold, Ravindranath Ramachandran
Homo- And Heteronuclear Clusters Of Platinum And Gold, Ravindranath Ramachandran
Digitized Theses
This thesis documents the chemistry of some homo- and heteronuclear cluster complexes of gold and platinum.;The reaction of (AuC{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu) with the diphosphine ligands, CH{dollar}\sb2{dollar}(PR{dollar}\sb2{dollar}){dollar}\sb2{dollar} (R = Me, dmpm; R = Ph, dppm; R = {dollar}-{dollar}OMe, dmopm), yielded a number of complexes. Complexes ({dollar}t{dollar}-BuC{dollar}\equiv{dollar}C-Au-R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}OR{dollar}\sb2{dollar}) (R = Me, Ph) were fluxional in solution. The crystal structures of (Au{dollar}\sb2{dollar}({dollar}\mu{dollar}-dmpm){dollar}\sb2{dollar}) X{dollar}\sb2\cdot{dollar}2H{dollar}\sb2{dollar}O (X = C{dollar}\ell{dollar}, I) were determined, as was that of (Au{dollar}\sb2{dollar}(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\sb2{dollar}({dollar}\mu{dollar}-dppm)). Complex (CH{dollar}\sb2\{lcub}{dollar}P(MeO){dollar}\sb2{dollar}Au(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\{rcub}\sb2{dollar}) oligomerized in chlorinated solvents to give (Au{dollar}\sb2{dollar}(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\{lcub}\mu\sb3- {dollar}(MeO){dollar}\sb2{dollar}PCHP(OMe){dollar}\sb2\{rcub}{dollar}) {dollar}\sb3{dollar}, and then (Au{dollar}\sb8{dollar}C{dollar}\ell\sb2\{lcub}\mu\sb3- {dollar}(MeO){dollar}\sb2{dollar}PCHP(OMe){dollar}\sb2\{rcub}\sb2\{lcub}\mu\sb4- {dollar}(MeO){dollar}\sb2{dollar}PCP(OMe){dollar}\sb2\{rcub}\sb2{dollar}) {dollar}\cdot{dollar}CHC{dollar}\ell\sb3{dollar}. The structure of the octagold cage was determined by X-ray crystallography, and was shown to …
Receptor Specific Radiotracers For Imaging Dopamine And Estrogen Receptors, Lou Anne Strickland
Receptor Specific Radiotracers For Imaging Dopamine And Estrogen Receptors, Lou Anne Strickland
Digitized Theses
The preparation and evaluation of potential dopamine receptor imaging agents and an estrogen receptor imaging agent is the topic of this thesis. The dopamine (D-2) receptor imaging agent could be employed as a diagnosis tool for several neurological diseases and the estrogen receptor agent could be used to detect estrogen receptor positive tumors.;Three different monoiodinated derivatives of the haloperidol were synthesised as potential D-2 agents. The results of an in vitro competitive binding assay showed one derivative to have much higher affinity than the other two for D-2 receptors. This derivative was labelled with 131-iodine and biodistribution studies in rats …
Characterization And Possible Functions Of A Collagen-Binding Protein From Skeletal Myoblasts, Devki Nandan
Characterization And Possible Functions Of A Collagen-Binding Protein From Skeletal Myoblasts, Devki Nandan
Digitized Theses
A 46 kDa glycoprotein (which had previously been implicated in myoblast differentiation) has been purified to homogeneity from L6 rat skeletal myoblasts. The sequence of 30 N-terminal amino acids has some resemblance to a sequence in myosin light-chain. The oligosaccharide chains of the glycoprotein can be released by treatment with glycosidase H suggesting that gp46 has a high mannose type of glycans. Gp46 is widely distributed and conserved in different cell lines as determined by immunoblotting using a monoclonal anti-gp46 antibody. High levels of gp46 were found in fibroblastic and myogenic, but not in haematopoietic cell lines. A survey of …
Synthesis And Photochemical Properties Of Some Porphyrin Derivatives, Kenneth James Roach
Synthesis And Photochemical Properties Of Some Porphyrin Derivatives, Kenneth James Roach
Digitized Theses
The initial step of photosynthesis involves transfer of an electron from a photo-excited porphyrin donor to a nearby ubiquinone acceptor. Compounds containing a porphyrin covalently linked to a benzoquinone have been shown to mimic this initial transfer and as such are useful models for the study of photo-induced intramolecular electron transfer. The first chapter of this thesis describes the synthesis of a linked porphyrin-benzoquinone species, designated P4Q. This compound consists of a tetra-aryl porphyrin linked cis-1,3 across a cyclobutane ring to a benzoquinone.;The photophysical properties of this compound and of two precursor species, the hydroquinone analog and the dimethoxy phenyl …
Stereoelectronic Effects, Mechanism, And Synthesis In Sulfonyl Chemistry, Rajendra Rathore
Stereoelectronic Effects, Mechanism, And Synthesis In Sulfonyl Chemistry, Rajendra Rathore
Digitized Theses
ABSTRACT HAS BEEN ARCHIVED 09/17/93;
Size Dependence Of Lateral Diffusion In Model Cell Membranes Using Fluorescently Labelled Probe Molecules, Bruce John Balcom
Size Dependence Of Lateral Diffusion In Model Cell Membranes Using Fluorescently Labelled Probe Molecules, Bruce John Balcom
Digitized Theses
Abstract Not Available.
Identification And Characterization Of The Hexose Transporters In Rat L6 Myoblasts, Sui Rong Chen
Identification And Characterization Of The Hexose Transporters In Rat L6 Myoblasts, Sui Rong Chen
Digitized Theses
Transport kinetic studies have demonstrated that two hexose transport systems are present in undifferentiated rat L6 myoblasts. These hexose transport systems were identified and characterized in this study using a number of different approaches. Cytochalasin B (CB), a potent inhibitor of hexose transport, was first used as a probe for these systems. CB binding studies with whole cells and membrane preparations revealed the presence of two distinct CB binding sites, CB{dollar}\sb{lcub}\rm H{rcub}{dollar} and CB{dollar}\sb{lcub}\rm L{rcub}{dollar}. They differ not only in their binding affinities, but also in their response to various biochemical, physiological and genetic manipulations. Based on the correlation between …
Electrochemical Studies Of Vanadium Oxides For Use In Lithium Batteries, Eddie Edmund Andrukaitis
Electrochemical Studies Of Vanadium Oxides For Use In Lithium Batteries, Eddie Edmund Andrukaitis
Digitized Theses
Vanadium oxides of varying stoichiometries have been studied for their potential use in rechargeable solid state lithium batteries. Deposits of hydrated diammonium hexavanadates have been prepared electrochemically on various conducting anode substrates. Coherent electrodeposits of highly oriented, crystalline M{dollar}\sb4{dollar}V{dollar}\sb6{dollar}O{dollar}\sb{lcub}16+\delta{rcub}{dollar}, where M = NH{dollar}\sb4{dollar}, K, Rb and Cs and 0.00 {dollar}<\delta<{dollar} 0.10, have also been made for the first time electrochemically on various conducting cathode substrates. Also, mixed crystalline phases of formula M{dollar}\sb{lcub}4-X{rcub}{dollar}N{dollar}\sb{lcub}X{rcub}{dollar}V{dollar}\sb6{dollar}O{dollar}\sb{lcub}16+\delta{rcub}{dollar}, where M, N = NH{dollar}\sb4{dollar}, K, Rb and Cs, M {dollar}\not={dollar} N and 0.00 {dollar}<\delta<{dollar} 0.13, have been made. The mechanism of formation of a deposit at the anode involves formation of a hydrated V{dollar}\sb2{dollar}O{dollar}\sb5{dollar} sol in a pH gradient at the anode, and subsequent electrophoretic deposition of the sol as an oriented crystalline deposit. The sol spreads to the cathode by convection, migration and diffusion, where the particles adhere with evidence of nucleation and growth on the cathode. These electrodeposits have been studied using both electrochemical and non-electrochemical techniques to determine their structure, stoichiometry and use as reversible insertion electrodes.;The deposits containing NH{dollar}\sb4\sp+{dollar} can be decomposed to crystalline V{dollar}\sb2{dollar}O{dollar}\sb5{dollar} by heating in air, or to non-stoichiometric V{dollar}\sb6{dollar}O{dollar}\sb{lcub}13{rcub}{dollar} by heating in argon or in vacuum at 300{dollar}\sp\circ{dollar}C for several hours, with retention of their orientation on the substrate. The first step of the thermal decomposition involves loss of 2NH{dollar}\sb3{dollar} + H{dollar}\sb2{dollar}O. In the second step, on heating in air, recrystallization and oxidation of V(IV) to V(V) is observed with the addition of 1/2 O to form V{dollar}\sb2{dollar}O{dollar}\sb5{dollar}. This oxidation is not seen on heating under reduced O{dollar}\sb2{dollar} partial pressure and reduction continues until V{dollar}\sb6{dollar}O{dollar}\sb{lcub}13+\delta{rcub}{dollar} is formed, where {dollar}\delta{dollar} is a function of how much residual O{dollar}\sb2{dollar} is left exposed to the deposit. Lithium could be reversibly inserted into and removed from the V{dollar}\sb2{dollar}O{dollar}\sb5{dollar} form of the deposit up to a mole ratio Li/V{dollar}\sb2{dollar}O{dollar}\sb5{dollar} = 1.2. For non-stoichiometric V{dollar}\sb6{dollar}O{dollar}\sb{lcub}13{rcub}{dollar} the ratio of Li/V{dollar}\sb6{dollar}O{dollar}\sb{lcub}13{rcub}{dollar} = 4.4. However, electrodes that were not decomposed inserted only a small amount of lithium, {dollar}<{dollar}1% of total V.;Single-cell batteries consisting of a Li anode, a polymer electrolyte such as MEEP, PEO or tetraglyme (supported in Celgard) and a vanadium pentoxide cathode have been studied. The batteries show favorable cycle lifetimes and high cathode capacity.
Age-Associated Changes In Tissue Dolichol And Dolichyl Phosphate Content And Metabolism, Dean Calvin Crick
Age-Associated Changes In Tissue Dolichol And Dolichyl Phosphate Content And Metabolism, Dean Calvin Crick
Digitized Theses
It is well known that dolichol accumulates with age in animal tissues. The mechanism of dolichol accumulation is not understood and it is unclear to what extent the accumulation of this compound affects the process of N-linked protein glycosylation.;In order to estimate the dietary contribution to body pools (1-{dollar}\sp{lcub}14{rcub}{dollar}C) dolichol was mixed in vitro with sunflower seed oil and given to rats by gavage. Less than 0.02% of the dose was found in the tissues after 12 h. The majority of the absorbed radioactivity was found in the liver at this time. There was no indication of catabolism of the …
Gas Phase Photoelectron Studies Of Organoplatinum Complexes Using Helium I, Helium Ii And Synchrotron Radiation, Dong-Sheng Yang
Gas Phase Photoelectron Studies Of Organoplatinum Complexes Using Helium I, Helium Ii And Synchrotron Radiation, Dong-Sheng Yang
Digitized Theses
Gas-phase He I and He II photoelectron spectra of four series of organoplatinum complexes are reported, together with synchrotron radiation photoelectron spectra of CpPtMe{dollar}\sb3{dollar} (Cp = {dollar}\eta\sp5{dollar}-C{dollar}\sb5{dollar}H{dollar}\sb5{dollar}) and PtMe{dollar}\sb2{dollar} (COD) (COD = 1,5-cyclooctadiene). The platinum complexes investigated with both He I and He II sources include square-planar cis-dimethylplatinum(II), square-planar cis-bis(trifluoromethyl)platinum(II), half-sandwich ({dollar}\eta\sp5{dollar}-cyclopentadienyl)trimethylplatinum(IV), and octahedral-like ({dollar}\beta{dollar}-diketonato)trimethylplatinum(IV) complexes. The electronic structures of the complexes studied are discussed using the He I and He II spectral information, such as the ionization energy shifts from ligand substitutions and the resolved vibrational splittings from ligand-based orbitals, and using X{dollar}\alpha{dollar}-SW calculations on some model compounds. The …