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Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle Jan 1994

Expression Of Prelamin A Confers Sensitivity Of Dna Biosynthesis To Lovastatin On F9 Teratocarcinoma Cells, Michael Sinensky, T. Mclain, K. Fantle

Faculty Publications, Biological Sciences

No abstract provided.


The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton Jan 1994

The Processing Pathway Of Prelamin A, Michael Sinensky, K. Fantle, M. Trujillo, T. Mclain, A. Kupfer, M. Dalton

Faculty Publications, Biological Sciences

The conversion of mammalian prelamin A to mature lamin A proceeds through the removal of 18 amino acids from the carboxyl terminus. The initial step in this processing is the isoprenylation of a CAAX box cysteine. This proteolytic event is distinctive for prelamin A among the known prenylated mammalian proteins. Since the carboxyl terminus of prelamin A is removed during maturation, it is not obvious that this protein would undergo the two reactions subsequent to prenylation observed in other CAAX box proteins-the endoproteolytic removal of the carboxyl-terminal 3 amino acids and the subsequent methylation of the now carboxyl-terminal cysteine. To …


Flash Pyrolysis-Gas Chromatography/Mass Spectrometry Of Lower Kittanning Vitrinites: Changes In The Distributions Of Polyaromatic Hydrocarbons As A Function Of Coal Rank, Michael A. Kruge, David F. Bensley Jan 1994

Flash Pyrolysis-Gas Chromatography/Mass Spectrometry Of Lower Kittanning Vitrinites: Changes In The Distributions Of Polyaromatic Hydrocarbons As A Function Of Coal Rank, Michael A. Kruge, David F. Bensley

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Chemical analyses restricted to a single coal maceral permit a focus on rank effects without concern for variations in organic matter type. Vitrinite concentrates of high purity were isolated from coal samples of the Lower Kittanning seam by multi-step density gradient centrifugation, with reflectances ranging from 0.66 to 1.39% Rmax. In addition to the previously recognized losses of phenolic compounds, the vitrinite pyrolyzates exhibit marked increases in relative concentrations of tri- and tetraaromatic hydrocarbons (especially benzo[a]fluorene, methyl-phenanthrenes, methylfluorenes and methylchrysenes) above 0.9% Rmax, i.e., beyond the "second coalification jump" of Teichmüller. Thus, petrographically-recognizable physical transformations are shown …


Synthesis Of Malathion, Malaoxon, And Isomalathion Enantiomers And Examination Of Their Interactions With Acetylcholinesterase, Clifford E. Berkman Jan 1994

Synthesis Of Malathion, Malaoxon, And Isomalathion Enantiomers And Examination Of Their Interactions With Acetylcholinesterase, Clifford E. Berkman

Dissertations

No abstract provided.


Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan Jan 1994

Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan

Journal of the Arkansas Academy of Science

No abstract provided.


Studies Directed Toward The Synthesis Of Germacranolides Via [2+2] Cycloaddition Followed By Ring Expansion/Elimination Of Β-Lactones, Bryan E. Yates Jan 1994

Studies Directed Toward The Synthesis Of Germacranolides Via [2+2] Cycloaddition Followed By Ring Expansion/Elimination Of Β-Lactones, Bryan E. Yates

Masters Theses

Exposure of α-trimethylsilyl β-lactones to magnesium bromide or boron trifluoride etherate in diethyl ether solvent resulted in the smooth generation of β,γ-unsaturated acid derivatives in good yield and isomeric purity. It is believed that this reaction occurs via the formation of a stable tertiary carbocation at the γ-carbon resulting from cleavage of the carbon-oxygen sigma bond due to the complexation of the Lewis acid with the ring oxygen atom. Rapid loss of an adjacent electrofuge then furnishes the unsaturated acids. The β-lactone precursors were prepared by a [2+2] cycloaddition of an aldehyde and an alkyl trimethylsilyl ketene. This method was …


The Synthesis And Characterization Of Ruii(Bpy){(Bpyrm)Ruii(Nh3)4}2](Pf6)6 And [Ruii(Bpy)2(Bpyrm)Ruii(Nh3)4](Pf6)4, Rick Anthony Pavinato Jan 1994

The Synthesis And Characterization Of Ruii(Bpy){(Bpyrm)Ruii(Nh3)4}2](Pf6)6 And [Ruii(Bpy)2(Bpyrm)Ruii(Nh3)4](Pf6)4, Rick Anthony Pavinato

Masters Theses

This thesis describes the synthesis of a trimetallic RuII complex [RuII(bpy){(bpyrm)RuII(NH3)4}2](PF6)6 and its bimetallic analog [RuII(bpy)2(bpyrm)RuII(NH3)4](PF6)4. The trimetallic species was designed to be the first in a series of complexes where the reduction potential of the "bridging" complex could be varied (relative to the "terminal" sites) through systematic variation in the metal (M) and/or ligand (LL) … Generation of the [RuII-MII-RuIII] "mixed-valence" complex would then allow …


Carbonyl Homologation Via Α-Trimethylsilyl Β-Lactone Rearrangement: A Nonbasic Wittig Alternative, Yong Zhang Jan 1994

Carbonyl Homologation Via Α-Trimethylsilyl Β-Lactone Rearrangement: A Nonbasic Wittig Alternative, Yong Zhang

Masters Theses

Our research group has been interested in β-lactones as useful synthetic intermediates. Transformations of β-lactones, generally ring expansion/opening processes initiated by Lewis acids via ionization/cation-rearrangement or elimination mechanisms, provide efficient protocols for the syntheses of biologically important butyrolactones, β,γ-unsaturated carboxylic acids, or butenolides.

α-Trimethylsilyl β-lactones, synthesized via the BF3- catalyzed [2+2] cycloaddition of trimethylsilylketene to carbonyl compounds, spontaneously undergo ionization and trimethylsilyl group migration to form α,β-unsaturated trimethylsilyl esters. The trimethylsilyl moiety facilitates the ionization process because of its β-cation stabilizing ability. The two-carbon homologated α,β-unsaturated acids are formed in yields from moderate to high (41-99%) upon aqueous …


Molecular Modeling Studies Of Hemoglobin Crosslinking Reactions, Patricia A. Pavlik Jan 1994

Molecular Modeling Studies Of Hemoglobin Crosslinking Reactions, Patricia A. Pavlik

Master's Theses

No abstract provided.


Comparing Normal And Sickle Hemoglobin Oxidation And Heme Transfer In The Presence Of Phosphatidylserine Vesicles, Qinghai Pan Jan 1994

Comparing Normal And Sickle Hemoglobin Oxidation And Heme Transfer In The Presence Of Phosphatidylserine Vesicles, Qinghai Pan

Master's Theses

No abstract provided.


Reaction Of Titanocene Dichloride With Acetylenedicarboxylate, Tanya L. Hagler, Mark Draganjac, Paul M. Nave, J. Ed Bennett, Farooq Kahn, Robert Engelken, Gerard Williams, Chris Poole, Kwok Fai Yu Jan 1994

Reaction Of Titanocene Dichloride With Acetylenedicarboxylate, Tanya L. Hagler, Mark Draganjac, Paul M. Nave, J. Ed Bennett, Farooq Kahn, Robert Engelken, Gerard Williams, Chris Poole, Kwok Fai Yu

Journal of the Arkansas Academy of Science

The reaction of Cp2TiCl2 with either the mono- or dipotassium salt of acetylenedicarboxylic acid (ADC) gives high yields of an insoluble orange product. The insoluble compound shows potential semiconductor behavior, as evidenced by an apparent bandgap in the orange region of the visible spectrum. Under N2 ,the compound decomposes at 238° C, eventually losing approximately 46% total mass up to 1350° C. The exothermic decomposition in air, beginning at 235° C, results in the formation of titanium oxides.


Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac Jan 1994

Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac

Journal of the Arkansas Academy of Science

Initial studies involved the thermal decomposition profile of five polysulfide complexes in air up to 550 °C. Since our first report to the Academy in 1990, we have obtained the capability to run samples up to 1500°C under various gases. Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA)of a series of transition metal polysulfide complexes are presented. Compounds analyzed included Cp2TiS5 ,MoS9 2",MoOS8 2", Zn(S x ) 2", Cd(S x ) 2-, Fe2S122 - and NiS82.


Structural Characterization Of Recombinant Polypeptides Of &-Spectrin, Yirong Xu Jan 1994

Structural Characterization Of Recombinant Polypeptides Of &-Spectrin, Yirong Xu

Dissertations

No abstract provided.


Chiral Isoparathion Methyl As A Stereospecific Probe Of Phosphorothiolate Mechanism Of Action; Novel Synthetic Approaches Toward Isoquinolone Alkaloids: Pancratistatin Study, Seungmin Ryu Jan 1994

Chiral Isoparathion Methyl As A Stereospecific Probe Of Phosphorothiolate Mechanism Of Action; Novel Synthetic Approaches Toward Isoquinolone Alkaloids: Pancratistatin Study, Seungmin Ryu

Dissertations

No abstract provided.


Purification And Analysis Of Protein Synthetic Initiation Factors From Volvox Carteri, Kathie L. Pooler Jan 1994

Purification And Analysis Of Protein Synthetic Initiation Factors From Volvox Carteri, Kathie L. Pooler

Honors Theses

Volvox carteri, a multi-celled green algae, can grow synchronously given a sixteen hour light period followed by an eight hour dark period, a cycle which is repeated for a 48 hour growth cycle total. Near the end of each light period, reproductive cells divide rapidly resulting in the differentiation of ceIls. When the dark period begins, this differentiation stops and the cells remain dormant with little protein synthesis or differentiation occurring. Immediately after the lights come back on, however, the cells again undergo rapid protein synthesis and complete their differentiation. Previous studies have concluded that Volvox carteri discontinue protein synthesis …


Kinetic And Chemical Modification Studies On Malate Dehydrogenase From E. Coli, Fang Jenny Zhao Jan 1994

Kinetic And Chemical Modification Studies On Malate Dehydrogenase From E. Coli, Fang Jenny Zhao

Masters Theses

Malate dehydrogenase (MDH) is the enzyme which catalyzes the conversion of malate to oxaloacetate in the TCA cycle. The object of this research was to discipher the mechanism of the reaction and the function of the enzyme. MDH from E. Coli was purified and analyzed by chemical modification studies using diethylpyrocarbonate. Results indicate the existence of a histidine residue at the active site necessary for catalysis. From kinetic studies, a group required for catalysis with a pKa of 8.5 was observed, which we believe to be a histidine residue. These studies indicate that MDH from E. Coli has a …


A Spectroscopic Study Of Nitrogen, Nitrogen/Helium And Fluorobenzenes In A Corona Supersonic Discharge, Jing-Chen Luo Jan 1994

A Spectroscopic Study Of Nitrogen, Nitrogen/Helium And Fluorobenzenes In A Corona Supersonic Discharge, Jing-Chen Luo

Dissertations

No abstract provided.


Lithium Binding To Human Rbc Membranes And Substrates Of Second Messenger Systems, Qinfen Rong Jan 1994

Lithium Binding To Human Rbc Membranes And Substrates Of Second Messenger Systems, Qinfen Rong

Dissertations

No abstract provided.


An Investigation Into Clay Intrinsic Properties, Surface Modifications And Applications, G Robert Goss Jan 1994

An Investigation Into Clay Intrinsic Properties, Surface Modifications And Applications, G Robert Goss

Dissertations

No abstract provided.


Segmental Motions Of Oxidized Human Erythrocyte Spectrin-Actin: A Spin Label Epr Study, Benito O. Kalaw Jan 1994

Segmental Motions Of Oxidized Human Erythrocyte Spectrin-Actin: A Spin Label Epr Study, Benito O. Kalaw

Dissertations

No abstract provided.


Synthesis Of Enantioenriched Piperidine-Based, Spirocyclic Analogues Of Af64a And Acetylcholine, Nam Huh Jan 1994

Synthesis Of Enantioenriched Piperidine-Based, Spirocyclic Analogues Of Af64a And Acetylcholine, Nam Huh

Dissertations

No abstract provided.


Development And Functional Properties Of Intramolecular Crosslinked Hemoglobin, Qunyang Zhang Jan 1994

Development And Functional Properties Of Intramolecular Crosslinked Hemoglobin, Qunyang Zhang

Dissertations

No abstract provided.


Detection Of Alzheimer's Disease And Other Diseases Using An Improved Photoaffinity Labeling Method, Boyd E. Haley Dec 1993

Detection Of Alzheimer's Disease And Other Diseases Using An Improved Photoaffinity Labeling Method, Boyd E. Haley

Chemistry Faculty Patents

A method for diagnosing a neurological disease comprising detecting a neurological disease-specific biochemical marker macromolecule within a sample of extracted cerebral spinal fluid is disclosed. In particular, a radioactively labeled photoaffinity probe is used to diagnose a neurological disease. For instance, Alzheimer's disease can be diagnosed by detecting a disease-specific protein having a molecular weight of about 42,000 daltons, i.e., glutamine synthetase.


Senior Theses: Department Of Physical Sciences, Frank Baldridge, Billy B. Stapleton, James Bond, Mark A. Blair Dec 1993

Senior Theses: Department Of Physical Sciences, Frank Baldridge, Billy B. Stapleton, James Bond, Mark A. Blair

Morehead State Theses and Dissertations

1993 Fall Semester Senior Theses for the class Physical Science 471:

Petrologic Classification of Igneous and Metamorphic Rocks by Frank Baldridge

X -Ray Analysis of Cave Sediments From Pigeon Water Cave of Northeastern Pine Mountain by Billy B. Stapleton

The Correlation of Stream-deposited Breccias In Bat Cave, Carter Caves, Kentucky by James Bond

Jointing and Faulting in Selected Areas of Eastern Kentucky by Mark A. Blair


Thermodynamic Properties Of Mixtures Of Aqueous Solutions Of Hydrochloric Acid And Cadmium Chloride, Copper Chloride, Manganese Chloride, And Zinc Chloride, Samia A. Kosa Dec 1993

Thermodynamic Properties Of Mixtures Of Aqueous Solutions Of Hydrochloric Acid And Cadmium Chloride, Copper Chloride, Manganese Chloride, And Zinc Chloride, Samia A. Kosa

Masters Theses

The densities of mixtures of aqueous solutions of hydrochloric acid and cadmium chloride, copper chloride, manganese chloride, and zinc chloride have been measured at constant ionic strengths of 1.0 and 3.0 molal at 25 °C. In the case of HCl, CdCl2 , and ZnCl2 the literature data were refit using Pitzer' s apparent molal volume equation and the binary solution parameters were determined. Density data were used to determine the volume of mixing (∆Vm). Data from Torok and Berecs were combined with our data for the mixtures with CuCl2 and MnCl2. Pitzer's volume …


A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane Dec 1993

A Characterization Of Extractable, Hydroxylated Fatty Acid Bearing Components In Legionella Pneumophila, Jonathan R. Lane

Electronic Theses and Dissertations

Extraction of the lipids of Legionella pneumophila yields phases unlike those produced from other Gram-negative bacteria. A viscous interface forms between the aqueous (wash) and organic phases. More than half of the hydroxylated fatty acids were found distributed between the aqueous phase and the interfacial material, fractions in which such constituents have not been reported in other Gram-negative species. It was further observed that after the material from the aqueous/interfacial phase was dissolved in methanol or chloroform/methanol (2:1 (V/V)), the addition of acetone would create a white, flocculent precipitate. Analyses showed that the supernatant contained fatty acids that were nonhydroxylated …


Nitric Oxide Absorption From Flue Gas With Cumene Hydroperoxide Solution, Chung-Der Chen Oct 1993

Nitric Oxide Absorption From Flue Gas With Cumene Hydroperoxide Solution, Chung-Der Chen

Theses

The absorption of nitric oxide from gas streams with cumene hydroperoxide (CHP) in n-hexadecane (cetane) as the scrubbing solution was investigated. The efficiency of the scrubbing solution to remove nitric oxide was evaluated over the temperature range of 90 to 110°C, concentration range of 0.1 to 0.5M, and residence time of 12 to 80 seconds. The products were analyzed by gas chromatography (GC), Fourier transform infrared spectroscopy (FTIR), and ion chromatography (IC). The goal of this research was to determine the NO removing efficiency of cumene hydroperoxide solution, a relatively inexpensive tertiary organic hydroperoxide. Also, a possible reaction mechanism for …


Interaction Of Cationic Porphyrins With Dna, Ulrica Sehlstedt, Pamela Carter, Jerry Goodisman, James C. Dabrowiak, Seog K. Kim Oct 1993

Interaction Of Cationic Porphyrins With Dna, Ulrica Sehlstedt, Pamela Carter, Jerry Goodisman, James C. Dabrowiak, Seog K. Kim

Chemistry - All Scholarship

Utilizing linear dichroism (LD), circular dichroism (CD), and fluorescence energy transfer, the binding geometries of a series of Co3+-porphyrins and their free ligands were examined. The compounds studied were Co-meso-tetrakis(N-methylpyridinium-4-yl)porphyi(nC oTMPyP) and its free ligand (H2- TMPyP), Co-meso-tetrakis(N-n-butylpyridinium-4-yl)porphyrin( CoTBPyP) and its free ligand (H2TBPyP), and Co-meso-tetrakis(N-n-octylpyridinium-4-yl)porphyrin (CoTOPyP). The two non-metalloporphyrins exhibit negative LD, having angles of roughly 75' relative to the DNA helix axis. They also display negative CD and a significant contact energy transfer from the DNA bases. On the other hand, the three metalloporphyrins display orientation angles of roughly 45' between the porphyrin plane and the helix axis …


Identification And Quantitation Of Volatile Amines In Chesapeake Bay Sediments, Neeraja Y. Krishna Oct 1993

Identification And Quantitation Of Volatile Amines In Chesapeake Bay Sediments, Neeraja Y. Krishna

Chemistry & Biochemistry Theses & Dissertations

Sediments from different parts of the Chesapeake Bay were analyzed to determine the presence of volatile amines. A HF-HCl extraction method was used to extract both exchangeable and fixed amines from the sediments and a purge-and-trap technique was used to concentrate the amines. Following derivatization with heptafluorobutyric anhydride (HFBA), the HFBA-amines were analyzed by gas chromatography with electron capture detection and with mass spectrometric detection. One primary amine, i-amylamine with a concentration ranging from 0. 78 nmoles/g dry weight to < 0.05 nmoles/g dry weight was found in a total of twenty seven samples collected on three different dates in 1993. Another primary amine, 2-methylbutylamine with a concentration ranging from 0.18 nmoles/g dry weight to < 0.05 nmoles/g dry weight was found in a total of twenty three samples collected on three different dates in 1993. A secondary amine, diethylamine was detected but could not be quantified in a total of seven samples collected in September 1993. The concentrations of these amines varied with location in the Bay, depth in the sediment, and time of year the sediments were collected. The origin of i-amylamine and 2-methylbutylamine might be from the biological decarboxylation of amino acids leucine and isoleucine, respectively. The origin of diethylamine is unknown.


The 2′-Phosphate Of Nadp Is Critical For Optimum Productive Binding To 6-Phosphogluconate Dehydrogenase From Candida Utilis, Anthony J. Berdis, Paul F. Cook Sep 1993

The 2′-Phosphate Of Nadp Is Critical For Optimum Productive Binding To 6-Phosphogluconate Dehydrogenase From Candida Utilis, Anthony J. Berdis, Paul F. Cook

Chemistry Faculty Publications

Initial velocity studies obtained with alternative dinucleotide substrates for the 6-phosphogluconate dehydrogenase reaction suggest that the 2′-phosphate is critical for the optimum productive binding of the dinucleotide substrate. Initial velocity patterns obtained by varying 6-phosphogluconate at different fixed levels of NAD are nearly parallel with apparent competitive substrate inhibition by 6-phosphogluconate at pH 7 and below but intersect to the left of the ordinate at pH 8 and above. Dead-end inhibition studies indicate that the mechanism is random at all pH values. Data are interpreted in terms of a random mechanism with marked antagonism in the binding of NAD and …