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Sds Non-Acrylamide Polymeric Gel-Filled Capillary Electrophoresis For Molecular Size Separation Of Protein, Devon Andres Aug 1993

Sds Non-Acrylamide Polymeric Gel-Filled Capillary Electrophoresis For Molecular Size Separation Of Protein, Devon Andres

Honors Theses

Sodium dodecyl sulfide (SDS) non-acrylamide gel-filled capillary columns are a new technology being used for analysis and separation of biotechnology-derived proteins. This research was to compare this new technology to the current methods of SDS polyacrylamide gel electrophoresis (SDS-PAGE) and high-performance size-exclusion chromatography (HPSEC). The molecular mass of four different recombinant proteins were determined by two commercialized SDS non-acrylamide gel-filled capillary columns, SDS-PAGE, and HPSEC. The data obtained showed that the SDS non-acrylamide gel-filled capillary columns were compatible with the SDS-PAGE technique for molecular mass determination. HPSEC was shown to be unreliable for molecular weight determination. SDS non-acrylamide gel-filled capillary …


The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy Jul 1993

The Isolation And Identification Of Polyphenolics From Grape Seeds And Their Activity Towards Specific Cell Lines, Joseph A. Reddy

Chemistry & Biochemistry Theses & Dissertations

Grape seed extract is being marketed in France for cardiovascular use and skin care. The active constituents of both these drugs are certain polyphenols called procyanidins. A similar seed extract has now been obtained from Virginia Chardonnay grape seeds. Ten of the major components in this extract have been isolated in their pure form by the semi-preparative HPLC separation on a YMC ODS-AQ (Octadecylsilane-AQ) column. The ODS-Aq column has been shown to have a better resolving capacity compared to the Spherisorb ODS (Octadecylsilane) column previously described in the literature. This has been attributed to the ODSAQ support which has both …


Formation Of O-Tyrosine And Dityrosine In Proteins During Radiolytic And Metal-Catalyzed Oxidation, Thomas G. Huggins, Mary C. Wells-Knecht, Nicholas A. Detorie, John W. Baynes, Suzanna R. Thorpe Jun 1993

Formation Of O-Tyrosine And Dityrosine In Proteins During Radiolytic And Metal-Catalyzed Oxidation, Thomas G. Huggins, Mary C. Wells-Knecht, Nicholas A. Detorie, John W. Baynes, Suzanna R. Thorpe

Faculty Publications

To evaluate their usefulness as chemical indicators of cumulative oxidative damage to proteins, we studied the kinetics and extent of formation of ortho-tyrosine (0-Tyr), dityrosine (DT), and dityrosine-like fluorescence (Ex = 3 17 nm, E,,, = 407 nm) in the model proteins RNase and lysozyme exposed to radiolytic and metalcatalyzed (H20z/Cu2+) oxidation (MCO). Although there were protein-dependent differences, o-Tyr, DT, and fluorescence increased coordinately during oxidation of the proteins in both oxidation systems. The contribution of DT to total dityrosine-like fluorescence in oxidized proteins varied from 2-10070, depending on the protein, type of oxidation, and extent of oxidative damage. In …


Oxidized Amino Acids In Lens Protein With Age: Measurement Of O-Tyrosine And Dityrosine In The Aging Human Lens, Mary C. Wells-Knect, Thomas G. Huggins, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes Jun 1993

Oxidized Amino Acids In Lens Protein With Age: Measurement Of O-Tyrosine And Dityrosine In The Aging Human Lens, Mary C. Wells-Knect, Thomas G. Huggins, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes

Faculty Publications

The concentrations of ortho-tyrosine (o-Tyr) and dityrosine (DT) were measured in noncataractous human lenses in order to assess the role of proteinoxidation reactions in the aging of lens proteins. The measurements were conducted by selected ion monitoring-gas chromatography/mass spectrometry using deuterium-labeled internal standards, which provided both high sensitivity and specificity for the quantitation of o-Tyr and DT. Between ages 1 and 78 years, the o-Tyr concentration in lens proteins varied from 0.3 to 0.9 mmol of o-Tyr/mol of Phe (n = 19), while DT ranged from 1 to 3 mumol of DT/mol of Tyr (n = 30). There were no …


The Cytotoxic Effect Of Tropical Plants On Human And Rat Hepatoma Cells, Mark Tafazoli Jun 1993

The Cytotoxic Effect Of Tropical Plants On Human And Rat Hepatoma Cells, Mark Tafazoli

Honors Capstone Projects and Theses

No abstract provided.


Photochemistry Of Nitrous Acid And Nitrite Ion, Kathryn E. Shanks '93 May 1993

Photochemistry Of Nitrous Acid And Nitrite Ion, Kathryn E. Shanks '93

Honors Projects

Research is currently underway to elucidate the photochemical decomposition mechanism of nitrous acid and nitrite ion in aqueous and non-aqueous media. The quantum yield of the photochemical disappearance of nitrous acid and nitrite, as a function of pH and nitrous acid/nitrite ion concentration ratios, was examined. Spectroscopic studies have been done with nitrite ion in various aprotic organic solvents. Similar work has been started with molecular nitrous acid that was produced in aqueous solution and then extracted into organic solvents. These organic solvents were employed in order to study the quantum yield with respect to NO2- and HONO without the …


Development Of New Methods For Assessing Solidification/Stabilization Of Hazardous Waste Using Solid-State Nuclear Magnetic Resonance Techniques (Ph.D Dissertation, Lsu), Michael A. Janusa May 1993

Development Of New Methods For Assessing Solidification/Stabilization Of Hazardous Waste Using Solid-State Nuclear Magnetic Resonance Techniques (Ph.D Dissertation, Lsu), Michael A. Janusa

Faculty Publications

New methods for assessing solidification/stabilization (S/S) of hazardous waste using solid-state nuclear magnetic resonance are developed for the purpose of diagnosing on a microscopic level the performance of S/S as a hazardous waste disposal technique. There are four techniques developed and described in this dissertation: (1) Solid-state deuterium NMR spectroscopy is used to determine if a particular deuterated organic waste is effectively solidified/stabilized and to determine the lower limit of the bond strength between the waste and the cement matrix; (2) Constant time pulsed field gradient ^ NMR spectroscopy is tested on a liquid waste encapsulated within a solidified matrix …


Peroxyoxalate Chemiluminescence And Capillary Electrophoresis : New Methods For Bioanalytical Chemistry, Nian Wu Apr 1993

Peroxyoxalate Chemiluminescence And Capillary Electrophoresis : New Methods For Bioanalytical Chemistry, Nian Wu

Graduate Dissertations and Theses

The general research objectives lie in the development of new approaches to improve chemical analysis in the area of bioanalytical chemistry. More specifically this thesis is focused on the development and application of new methodologies and instrumentation involving two potentially powerful techniques: 1) Chemiluminescence-a spectroscopic technique in which the generation of fluorescence from the electronically excited state of the molecule is provided by a chemical reaction and 2) Capillary electrophoresis-a separation technique in which small ions as well as large biomolecules can be separated with high efficiency within a narrow capillary under the influence of high voltage.


Investigation Of The Structural Heterogeneity Of Lipooligosaccharides From Pathogenic Haemophilus And Neisseria Species And Of R-Type Lipopolysaccharides From Salmonella Typhimurium By Electrospray Mass Spectrometry, B W. Gibson, William Melaugh, Nancy J. Phillips, M A. Apicella, A A. Campagnari, J M. Griffiss Jan 1993

Investigation Of The Structural Heterogeneity Of Lipooligosaccharides From Pathogenic Haemophilus And Neisseria Species And Of R-Type Lipopolysaccharides From Salmonella Typhimurium By Electrospray Mass Spectrometry, B W. Gibson, William Melaugh, Nancy J. Phillips, M A. Apicella, A A. Campagnari, J M. Griffiss

Chemistry Faculty Publications

Heterogeneity in the lipooligosaccharides (LOS) of pathogenic Haemophilus and Neisseria species is evident from the multiplicity of components observed with electrophoretic analyses. Knowledge of the precise structures that make up these diverse LOS molecules is clearly the key to reaching an understanding of pathogenic processes such as phase variation and molecular mimicry. Except for a few cases, little is known about the specific structural features of LOS that underlie phase variation and molecular mimicry, partly because of the inherent difficulties in the structural elucidation of these complex glycolipids. In the lipopolysaccharides (LPS) from Salmonella typhimurium and Escherichia coli, rough, or …


Rapamycin Inhibition Of Interleukin-2-Dependent P33(Cdk2) And P34(Cdc2) Kinase Activation In T Lymphocytes, W. G. Morice, Gregory Wiederrecht, Gregory J. Brunn, John Siekierka, R. T. Abraham Jan 1993

Rapamycin Inhibition Of Interleukin-2-Dependent P33(Cdk2) And P34(Cdc2) Kinase Activation In T Lymphocytes, W. G. Morice, Gregory Wiederrecht, Gregory J. Brunn, John Siekierka, R. T. Abraham

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

The immunosuppressant rapamycin (RAP) is a potent inhibitor of the entry of interleukin (IL)-2-stimulated T cells into S-phase. Earlier results indicated that RAP treatment arrested the growth of the murine IL-2-dependent T cell line CTLL-2 in late G1-phase. To explore further the interactions of RAP with the cell cycle control machinery in T cells, we examined the effects of RAP treatment on the activation of the cyclin-dependent kinases p34(cdc2) and p33(cdk2) in G1-phase CTLL-2 cells. Stimulation of factor-deprived cells with IL-2 led to the assembly of high molecular weight complexes containing active p34(cdc2) and p33(cdk2). The appearance of these complexes …


Rapamycin-Induced Inhibition Of P34(Cdc2) Kinase Activation Is Associated With G1/S-Phase Growth Arrest In T Lymphocytes, W. G. Morice, Gregory J. Brunn, Gregory Wiederrecht, John Siekierka, R. T. Abraham Jan 1993

Rapamycin-Induced Inhibition Of P34(Cdc2) Kinase Activation Is Associated With G1/S-Phase Growth Arrest In T Lymphocytes, W. G. Morice, Gregory J. Brunn, Gregory Wiederrecht, John Siekierka, R. T. Abraham

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

The macrolide rapamycin (RAP) is a potent inhibitor of interleukin-2 (IL- 2)-induced T-cell proliferation. Current models suggest that RAP, when complexed to its intracellular receptor, FK506-binding protein, interferes with an IL-2 receptor-coupled signaling pathway required for cell-cycle progression from G1- to S-phase. Here we show that RAP treatment inhibits the growth of an IL-2-dependent cytotoxic T-cell line, CTLL-2, in late G1- phase, just prior to entry of the cells into S-phase. In contrast, RAP- treated CTLL-2 cells retained the ability to respond to IL-2 with enhanced cytolytic activity, indicating that RAP was not a general suppressant of cellular responsiveness to …


Soluble Highly Reactive Form Of Calcium And Reagents Thereof, Reuben D. Rieke Jan 1993

Soluble Highly Reactive Form Of Calcium And Reagents Thereof, Reuben D. Rieke

Department of Chemistry: Faculty Publications

A soluble highly reactive form of calcium, prepared from Ca(II) salts and a reducing agent in ethereal, polyethereal, or hydrocarbon solvents, is presented. This form of calcium can be used in the preparation of organocalcium reagents. The organocalcium reagents resulting from the reaction of the soluble highly reactive calcium with organic compounds containing either halide, cyanide, a 1,3-diene, or a polyunsaturated functionality, are stable, useful reagents for organic synthesis. The organocalcium halide reagents undergo Grignard-type reactions. They also undergo reactions with Cu(I) salts to form organocalcium cuprate reagents. The organocalcium cuprate reagents undergo a variety of cross-coupling reactions. The soluble …


Preparation Of Functionalized Polymers Utilizng A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke Jan 1993

Preparation Of Functionalized Polymers Utilizng A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke

Department of Chemistry: Faculty Publications

Calcium-substituted polymeric reagents are provided. These reagents can be prepared via the oxidative addition of a soluble highly reactive calcium species to organic and inorganic polymers containing alkyl, aryl, or alkylaryl pendent groups substituted with halide atoms, cyanide molecules, 1,3-dienes, or any conjugated poly unsaturated system. Preferably, the polymer is a cross linked p-bromopolystyrene, p-chloropolystyrene, p fluoropolystyrene, or chloromethylated polystyrene. Preferably, the soluble highly reactive calcium species is prepared from the reduction of Ca(II) salts with an alkali metal arene, such as lithium biphenylide. These calcium-substituted polymeric reagents react with a variety of electrophiles to yield functionalized polymers. Reaction with …


Synthesis And Characterization Of Transition Metal Polypyridyl Complexes With A Novel 1,10-Phenanthropteridinedione Ligand, Huakai Huang Jan 1993

Synthesis And Characterization Of Transition Metal Polypyridyl Complexes With A Novel 1,10-Phenanthropteridinedione Ligand, Huakai Huang

Masters Theses

A new alloxazine ligand (1; "Pptd"), produced by the condensation of 1,10-phenanthroline-5,6-dione with 5,6-diamino-1,3-dimethyluracil, and several transition metal complexes containing this ligand, have been synthesized. The Pptd ligands attach to Ru(II), Co(II), or Re(I) metal centers through the phenanthroline linkage to form stable polypyridyl complexes. The spectral and the electrochemical characterization of Pptd complexes of Ru(II), Co(II), and Re(I) is presented.

Pptd is capable of being reduced (across the pyrazine nitrogens) by two H-atoms. When coordinated to Ru(II), Pptd forms stable complexes which retain the robust characteristics and electrochemical activity of other Ru(II) polypyridyl species. In addition, Ru(II) complexes of …


A-Helical Polypeptide Monolayers, Erwin P. Enriquez Jan 1993

A-Helical Polypeptide Monolayers, Erwin P. Enriquez

Chemistry Faculty Publications

In efforts to utilize the a-helical structural motif as a basic building block in the formation of supramolecular assemblies, a study of the self-assembly of a-helical poly(glutamate)s from dilute solution onto a solid support was initiated. In particular, poly(y-benzyl-L-glutamate) [PBLG], which has an unusually robust a-helical conformation, was functionalized at the amino terminus with a disulfide-containing moiety (lipoic acid), which in turn has a specific and strong chemisorptive interaction with gold surfaces. The same end group functionalization was used with the /i-alkyl side chain analogs of PBLG. The resulting self-assembled monolayers were characterized by grazing angle reflection infrared (GIR-IR) spectroscopy, …


A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver Jan 1993

A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver

Faculty Publications and Presentations

Giant salvinia (Salviniaceae) is a potentially serious aquatic weed that is native to Brazil. It has been reported in more than 20 countries, but is not established in the U.S. at this time. Mitchell and Tur (1975) reported that three years after the formation of the Kariba Reservoir in Africa, giant salvinia blanketed 21.5% or 1003 km2 of the reservoir surface area. Creagh (199111992) wrote, "A single small plant may grow to form a thick mat covering more than 100 sq. km. in just three months - choking lakes and waterways, reducing populations of aquatic plants and animals and in …


Catecholamine Secretion In Bovine Chromaffin Cells : Influence Of Immune-Derived Factors, Zhaohui Wang Jan 1993

Catecholamine Secretion In Bovine Chromaffin Cells : Influence Of Immune-Derived Factors, Zhaohui Wang

Master's Theses

No abstract provided.


Nmr Study Of Na+-H+ And Na+-Li+ Exchange In Human Erythrocytes, Suilan Mo Jan 1993

Nmr Study Of Na+-H+ And Na+-Li+ Exchange In Human Erythrocytes, Suilan Mo

Master's Theses

No abstract provided.


Correlation Of 17o Chemical Shifts Of Chromium Carbene Complexes With Moss' Mxy Reacitvity Parameter, Shuyuan Liao Jan 1993

Correlation Of 17o Chemical Shifts Of Chromium Carbene Complexes With Moss' Mxy Reacitvity Parameter, Shuyuan Liao

Master's Theses

No abstract provided.


Pairwise And Many-Body Contributions To Interaction Potentials In He(N) Clusters, Carol A. Parish, Clifford E. Dykstra Jan 1993

Pairwise And Many-Body Contributions To Interaction Potentials In He(N) Clusters, Carol A. Parish, Clifford E. Dykstra

Chemistry Faculty Publications

High level ab initio calculations have been carried out to assess the pairwise additivity of potentials in the attractive or well regions of the potential surfaces of clusters of helium atoms. A large basis set was employed and calculations were done at the Brueckner orbital coupled cluster level. Differences between calculated potentials for several interacting atoms and the corresponding summed pair potentials reveal the three‐body and certain higher order contributions to the interaction strengths. Attraction between rare gas atoms develops from dispersion, and so helium clusters provide the most workable systems for analyzing nonadditivity of dispersion. The results indicate that …


A Comparative 2-Dimensional Gel Protein Database Of The Intact And Regenerating Newt Limbs, Panagiotis A. Tsonis Jan 1993

A Comparative 2-Dimensional Gel Protein Database Of The Intact And Regenerating Newt Limbs, Panagiotis A. Tsonis

Biology Faculty Publications

In this paper we describe a two-dimensional gel database of the regenerating newt limb. Protein synthesis was compared in the intact limb, in the 1-week regenerating limb, representing the dedifferentiation stage, and in the 2-week regenerating limb, representing the formation of the blastema. This comparative database provided data on differential expression of about 800 proteins during the process of limb regeneration. In addition, a map has been generated for these proteins for future guidance in characterizing further new, unknown proteins. The overall expression patterns of the proteins indicated that the dedifferentiation stage was marked by down-regulation of most proteins, while …


High-Energy Behavior Of The Double Photoionization Of Helium From 2 To 12 Kev, Jon C. Levin, Ivan A. Sellin, B. M. Johnson, Dennis W. Lindle, R. D. Miller, Y. Azuma, H. G. Berry, D.-H. Lee, N. Berrah Jan 1993

High-Energy Behavior Of The Double Photoionization Of Helium From 2 To 12 Kev, Jon C. Levin, Ivan A. Sellin, B. M. Johnson, Dennis W. Lindle, R. D. Miller, Y. Azuma, H. G. Berry, D.-H. Lee, N. Berrah

Chemistry and Biochemistry Faculty Research

We report the ratio of double-to-single photoionization of He at several photon energies from 2 to 12 keV. By time-of-Aight methods, we find a ratio consistent with an asymptote at 1.5%±0.2%, essentially reached by h v≈4 keV. Fair agreement is obtained with older shake calculations of Byron and Joachain [Phys. Rev. 164, 1 (1967)], of Aberg [Phys. Rev. A 2, 1726 (1970)], and with recent many-body perturbation theory (MBPT) of Ishihara, Hino, and McGuire [Phys. Rev. A 44, 6980 (1991)]. The result lies below earlier MPBT calculations by Amusia et al. [J. Phys. B 8 …


Telomere Processing In Euplotes, Joris Robert Vermeesch, Dewight Williams, Carolyn M. Price Jan 1993

Telomere Processing In Euplotes, Joris Robert Vermeesch, Dewight Williams, Carolyn M. Price

Department of Chemistry: Faculty Publications

In Euplotes crassus millions of telomeres are synthesized during the sexual phase of the life cycle. Since these newly synthesized telomeres are longer than normal macronuclear telomeres, they must be trimmed to the mature size. We have examined the timing and mechanism of this trimming step. We have shown that a sudden decrease in telomere length takes place at a specific time during macronuclear development. The decrease in telomere length is not caused by incomplete replication of the most terminal DNA sequences; rather it is the result of an active processing event that occurs independently of DNA replication. The developmentally …


Preparation Of Functionalized Polymers Utilizing A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke Jan 1993

Preparation Of Functionalized Polymers Utilizing A Soluble Highly Reactive Form Of Calcium, Reuben D. Rieke

Department of Chemistry: Faculty Publications

Calcium-substituted polymeric reagents are provided. These reagents can be prepared via the oxidative addition of a soluble highly reactive calcium species to organic and inorganic polymers containing alkyl, aryl, or alkylaryl pendent groups substituted with halide atoms, cyanide molecules, 1,3-dienes, or any conjugated poly unsaturated system. Preferably, the polymer is a cross linked p-bromopolystyrene, p-chloropolystyrene, p-fluoropolystyrene, or chloromethylated polystyrene. Preferably, the soluble highly reactive calcium species is prepared from the reduction of Ca(II) salts with an alkali metal arene, such as lithium biphenylide. These calcium-substituted polymeric reagents react with a variety of electrophiles to yield functionalized polymers. Reaction with Cu(I) …


Electrochemical Studies Of Swelling And Shrinking Of Clay Films, Jia Du Jan 1993

Electrochemical Studies Of Swelling And Shrinking Of Clay Films, Jia Du

Master's Theses

No abstract provided.


Self-Diffusion Studies In Polymer-Solvent Systems By Pulsed-Gradient Spin-Echo Nuclear Magnetic Resonance, R. Allen Waggoner Jan 1993

Self-Diffusion Studies In Polymer-Solvent Systems By Pulsed-Gradient Spin-Echo Nuclear Magnetic Resonance, R. Allen Waggoner

Doctoral Dissertations

"Pulsed gradient NMR techniques have been used to study self-diffusion in polymer solutions. The systems studied include toluene, cyclohexane, ethylbenzene, chloroform, t-butyl acetate, and methyl ethyl ketone in polystyrene; methyl methacrylate in poly(methyl methacrylate); poly(ethylene oxide) in water; and water in biological tissue. The polymer diffusion data are evaluated in terms of scaling theory as they relate to the scaling of the polymer diffusion coefficient with molecular weight. The solvent diffusion data are evaluated with kinetic and free-volume theories. In addition a relatively simple dependence of diffusion coefficient on polymer volume fraction is derived from free-volume theory. The solvent diffusion …


The Interaction Of Sickle Hemoglobin With Phosphatidylserine Vesicles ; Fourier Transform Infrared Spectroscopic Studies Of Human Erythrocyte Spectrin, Cynthia C. Labrake Jan 1993

The Interaction Of Sickle Hemoglobin With Phosphatidylserine Vesicles ; Fourier Transform Infrared Spectroscopic Studies Of Human Erythrocyte Spectrin, Cynthia C. Labrake

Dissertations

No abstract provided.


Polynuclear Mixed-Valence Complexes, David A. Rockcliffe Jan 1993

Polynuclear Mixed-Valence Complexes, David A. Rockcliffe

Dissertations

No abstract provided.


A Facile Route To Allylic Phosphonates Via Base-Catalyzed Isomerization Of The Corresponding Vinyl Phosphonates : Remote Dianions In Synthesis, Synthetic Approaches To The Indolizidines, James J. Kiddle Jan 1993

A Facile Route To Allylic Phosphonates Via Base-Catalyzed Isomerization Of The Corresponding Vinyl Phosphonates : Remote Dianions In Synthesis, Synthetic Approaches To The Indolizidines, James J. Kiddle

Dissertations

No abstract provided.


Β-Homopipitzolone, Ezequiel Huipe Nava, V. A. Igonin, Sergey V. Lindeman, Yuri T. Struchkov, V. Mendoza, G. Garcia, J. A. Guzman Jan 1993

Β-Homopipitzolone, Ezequiel Huipe Nava, V. A. Igonin, Sergey V. Lindeman, Yuri T. Struchkov, V. Mendoza, G. Garcia, J. A. Guzman

Chemistry Faculty Research and Publications

The structure of β-homopipitzolone (one of the two isomers of an intermediate product in the homocedrole synthesis) has been unequivocally established as 1 O-hydroxy-2,6,9-trimetbyltricyclo[6.3.1.01,6] dodeca-9-ene-5, II, 12-trione with relative IR,2R,6R,8S configuration.