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Strategies To Resolve The Three-Dimensional Structure Of The Genome Of Small Single-Stranded Icosahedral Viruses, Eduardo Sanz Garcia Dec 2010

Strategies To Resolve The Three-Dimensional Structure Of The Genome Of Small Single-Stranded Icosahedral Viruses, Eduardo Sanz Garcia

Theses and Dissertations

The aim of this study is the three-dimensional structural characterization of the genome packaging inside viral capsids via cryo-electron microscopy and three-dimensional reconstruction. The genome of some single-stranded viruses can be densely packaged within their capsid shells. Several stretches of the genome are known to adopt stable secondary structures, however, to date, little is known about the three-dimensional organization of the genome inside their capsid shells. Two techniques have been developed to facilitate the structural elucidation of genome packaging: the asymmetric random-model method, and the symmetry-mismatch, random model method. Both techniques were successfully tested with model and experimental data. The …


Chemical Vapor Deposition Of Silanes And Patterning On Silicon, Feng Zhang Dec 2010

Chemical Vapor Deposition Of Silanes And Patterning On Silicon, Feng Zhang

Theses and Dissertations

Self assembled monolayers (SAMs) are widely used for surface modification. Alkylsilane monolayers are one of the most widely deposited and studied SAMs. My work focuses on the preparation, patterning, and application of alkysilane monolayers. 3-aminopropyltriethoxysilane (APTES) is one of the most popular silanes used to make active surfaces for surface modification. To possibly improve the surface physical properties and increase options for processing this material, I prepared and studied a series of amino silane surfaces on silicon/silicon dioxide from APTES and two other related silanes by chemical vapor deposition (CVD). I also explored CVD of 3-mercaptopropyltrimethoxysilane on silicon and quartz. …


High Flow Air Sampling For Field Detection Using Gas Chromatography-Mass Spectrometry, Jacolin Ann Murray Dec 2010

High Flow Air Sampling For Field Detection Using Gas Chromatography-Mass Spectrometry, Jacolin Ann Murray

Theses and Dissertations

The ability to rapidly detect and identify hazardous analytes in the field has become increasingly important. One of the most important analytical detection methods in the field is gas chromatography-mass spectrometry (GC-MS). In this work, a hand-portable GC-MS system is described that contains a miniature toroidal ion trap mass analyzer and a low thermal mass GC. The system is self-contained within the dimensions of 47 x 36 x 18 cm and weighs less than 13 kg. Because the instrument has a small footprint, it was used as the detector for an automated near-real-time permeation testing system. In permeation testing, materials …


Work Towards The Isolation And Characterization Of The Muscle Isoform Of Glucose 1,6-Bisphosphatase, Caleb J. Hiller Nov 2010

Work Towards The Isolation And Characterization Of The Muscle Isoform Of Glucose 1,6-Bisphosphatase, Caleb J. Hiller

Theses and Dissertations

Glucose 1,6-bisphosphate is an important small molecule involved in the regulation of glycolysis. Four enzymes synthesize this compound. One enzyme is known to degrade it, glucose 1,6-bisphosphatase. Other groups have produced work that indicates that there are two isoforms of this enzyme, one predominant in the brain and one in the muscle. This thesis contains the work performed in attempts to isolate and characterize the muscle isoform of glucose 1,6-bisphosphatase. While this enzyme was not isolated, much was learned about it and the results from this work may help in the future identification of this enzyme.


Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang Nov 2010

Halo Ion Trap Mass Spectrometry: Design, Instrumentation, And Performance, Miao Wang

Theses and Dissertations

New ion trap mass spectrometry (ITMS) instrumentation, the toroidal IT and halo IT, were developed to meet the significant growth in on-site analysis applications. The miniature toroidal IT mass analyzer was operated with radio frequency (RF) trapping voltages of 3 kVp-p or less. Despite its reduced dimensions, it has roughly the same ion trapping capacity as conventional 3D quadrupole ITs. Unit-mass resolved spectra for n-butylbenzene, xenon, and naphthalene were obtained. The desired linear mass scale was obtained using conventional mass-selective instability scan combined with resonance ejection. The halo IT was also based on toroidal trapping geometry and microfabrication technology, consisting …


Adenovirus-5 Infection Affects Lipid Metabolism In Hepatic And Adipose Tissues, Marianna Sukholutsky Oct 2010

Adenovirus-5 Infection Affects Lipid Metabolism In Hepatic And Adipose Tissues, Marianna Sukholutsky

Theses and Dissertations

Our recent studies have shown a link between Adenovirus-5 (Ad-5) and elevated lipids, which prompted the hypothesis that Ad-5 infection might augment hepatic and/or adipose tissue lipid metabolism. To test our hypothesis, mice were infected with Ad-5 and screened for changes in lipogenesis and plasma markers associated with the metabolic syndrome. We observed increased expression of sterol regulatory element binding protein 1 (SREBP-1) in infected liver tissues, but not in adipose tissues and this correlated with elevated plasma and hepatic triglyceride levels. Elevated expression of adiponectin was seen in Ad-5 infected adipose tissues and this correlated with phosphorylated AMPK in …


Functionalization Of Diamond And Its Application In High Performance Liquid Chromatography And Solid Phase Extraction, Gaurav Saini Oct 2010

Functionalization Of Diamond And Its Application In High Performance Liquid Chromatography And Solid Phase Extraction, Gaurav Saini

Theses and Dissertations

The primary focus of my work was to chemically functionalize diamond as normal and reversed phases for solid phase extraction (SPE) and high performance liquid chromatography (HPLC). Diamond was functionalized with -NH2 groups via self-limiting adsorption of an amine-containing polymer, polyallylamine (PAAm), onto oxidized diamond particles. The chemical stability of these particles was improved by thermal curing or chemical crosslinking with 1,2,5,6-diepoxycyclooctane. The reversed phase material for SPE was synthesized by reacting amine-functionalized diamond particles with long chain alkyl and a perfluorinated isocyanate. Unlike commercially available silica, functionalized diamond particles were stable under extreme pH conditions (pH 0-14). Functionalized diamond …


The Regulation Of The Alternative Splicing Of Caspase 9, Rachel Goehe Sep 2010

The Regulation Of The Alternative Splicing Of Caspase 9, Rachel Goehe

Theses and Dissertations

The pro-apoptotic, caspase 9a, and the anti-apoptotic, caspase 9b, are derived from the caspase 9 gene by alternative splicing. This study demonstrates that the alternative splicing of caspase 9 is dysregulated in a large percentage of non-small cell lung cancer (NSCLC) tumors of the adenocarcinoma type. Furthermore, modulation of the levels of splice variants of caspase 9 had dramatic effects on the anchorage-independent growth and tumorigenic capacity of NSCLC cells. Due to these findings, the molecular mechanisms regulating the post-transcriptional processing of caspase 9 were therefore examined and an exonic splicing silencer (ESS) regulating the pre-mRNA processing of caspase 9 …


Specificity Determinants Of Arma, A Ribosomal Rna Methyltransferase That Confers Antibiotic Resistance, Tamara Zarubica Sep 2010

Specificity Determinants Of Arma, A Ribosomal Rna Methyltransferase That Confers Antibiotic Resistance, Tamara Zarubica

Theses and Dissertations

Bacterial resistance to 4,6-type aminoglycoside antibiotics, which target the 30S ribosomal subunit, has been traced to the arm/rmt family of rRNA methyltransferases. These plasmid-encoded enzymes transfer a methyl group from S-adenosylmethionine to N7 of the buried G1405 in the aminoglycoside binding site of 16S rRNA in the 30S ribosomal subunit. Neither 16S rRNA alone nor intact 70S ribosome is an efficient substrate for armA methyltransferase. To more fully characterize this family of enzymes, xiii we have investigated the substrate requirements of ArmA. We determined the Mg2+ dependence of ArmA activity and found that the enzyme could recognize both translationally active …


Axial Temperature Gradients In Gas Chromatography, Jesse Alberto Contreras Sep 2010

Axial Temperature Gradients In Gas Chromatography, Jesse Alberto Contreras

Theses and Dissertations

The easiest and most effective way to influence the separation process in gas chromatography (GC) is achieved by controlling the temperature of the chromatographic column. In conventional GC, the temperature along the length of the column is constant at any given time, T(t). In my research, I investigated the effects of temperature gradients on GC separations as a function of time and position, T(t,x), along the column. This separation mode is called thermal gradient GC (TGGC). The research reported in this dissertation highlights the fundamental principles of axial temperature gradients and the separation potential of the TGGC technique. These goals …


Integrated Affinity Column Capillary Electrophoresis Microdevices For Biomarker Analysis, Weichun Yang Aug 2010

Integrated Affinity Column Capillary Electrophoresis Microdevices For Biomarker Analysis, Weichun Yang

Theses and Dissertations

In this dissertation, microfluidic systems that integrate antibody-based sample preparation methods with electrophoretic separation are developed to analyze multiple biomarkers in a point-of-care setting. To form an affinity column, both monolith materials and wall-coated channels were explored. I successfully demonstrated that monolith columns can be prepared in microfluidic devices via photopolymerization. The selectivity of monolith columns was improved by immobilizing antibodies on the surface. These affinity columns can selectively enrich target analytes and reduce the signal of contaminant proteins up to 25,000 fold after immunoaffinity extraction. These results clearly demonstrate that microchip affinity monoliths can selectively concentrate and purify target …


Synthesis And Characterization Of An Oligothiophene-Ruthenium Complex And Synthesis And Optical Properties Of Oligothiophene-Ruthenium Complexes Bound To Cdse Nanoparticles, Nathan A. Bair Aug 2010

Synthesis And Characterization Of An Oligothiophene-Ruthenium Complex And Synthesis And Optical Properties Of Oligothiophene-Ruthenium Complexes Bound To Cdse Nanoparticles, Nathan A. Bair

Theses and Dissertations

Oligothiophenes are of increasing interest in organic based electronic devices in part due to their high electron and hole mobilities. In an organic photovoltaic (OPV) device, the electronic properties of oligothiophenes make them advantageous as charge transfer junctions. To serve as charge transfer junctions, oligothiophenes must be functionalized to bind to the donor and acceptor parts of the device. The donor and acceptor parts are different materials and the synthesis of asymmetric oligothiophenes is of great interest. Previous researchers in our lab synthesized four asymmetric oligothiophenes, two with two thiophene subunits and two with four. Each set of oligothiophenes contained …


Contribution Of Nuceliec Acids On The Structure Of Recombinant Hepadnavirus Core Antigens, Maimuna Bruce Jul 2010

Contribution Of Nuceliec Acids On The Structure Of Recombinant Hepadnavirus Core Antigens, Maimuna Bruce

Theses and Dissertations

The Hepatitis B core antigen (HBcAg) has been proposed to be an ideal candidate for use as an adjuvant due to its immunogenicity, and tolerance to manipulations such as insertions of epitopes or covalent attachment of ligands. HBcAg is a complex macromolecule containing protein and nucleic acid. We investigated the effect of the removal and reconstitution of nucleic acids upon its structure. It’s been shown that the RNA content of hepadnavirus core antigens can be reduced significantly, but not be completely removed. Following removal of some of the RNA, antigens retain the ability to bind added nucleic acids, in particular, …


Role Of Xrcc3 In Acquisition And Maintenance Of Invasiveness Through Extracellular Matrix In Breast Cancer Progression, Siddharth Saini Jul 2010

Role Of Xrcc3 In Acquisition And Maintenance Of Invasiveness Through Extracellular Matrix In Breast Cancer Progression, Siddharth Saini

Theses and Dissertations

Acquisition of invasiveness through extracellular matrix is a crucial characteristic of transition to malignancy in the breast. It was previously shown that Polo-like kinase 1 (PLK-1), a mitotic kinase and genome stability regulator, is involved in acquisition of invasiveness in a breast cell model (HMT-3522 cell line) of pre-invasive to invasive transition. This and other data led to the suggestion that a new class of genes called GISEM for Genome Instability and Extracellular Matrix Invasiveness may exist. Previous lab data show that XRCC3 is found downregulated in progression from preinvasive to invasive phenotype. This led to the hypothesis that XRCC3 …


Function And Regulation Of Matrix Metalloproteinase-1 In Glioblastoma Multiforme, Monika Anand Jul 2010

Function And Regulation Of Matrix Metalloproteinase-1 In Glioblastoma Multiforme, Monika Anand

Theses and Dissertations

Glioblastoma Multiforme (GBM) is an aggressive and fatal cancer of the brain. It is characterized with augmented morbidity and elusion to therapies due in part to the incessant infiltration and spread of tumor cells in normal brain. We investigated the function of Matrix metalloproteinase-1, an important enzyme noted to be responsible for invasion in other cancers, in GBM and its regulation by epidermal growth factor receptor (EGFR) signaling. Previous studies from our laboratory demonstrated elevated levels of MMP-1 in GBM. Further studies indicated the involvement of MMP-1 in GBM invasion. The GBM cell lines T98G, U251MG and U87MG were used …


Double-Strand Break Repair Mechanisms In Human Embryonic Stem Cells, Bret Adams Jul 2010

Double-Strand Break Repair Mechanisms In Human Embryonic Stem Cells, Bret Adams

Theses and Dissertations

Central to the progression of all organisms is the maintenance of a stable genome despite continuous insults arising from genotoxic and environmental stresses. Embryonic stem cells show promise for treatment of a variety of diseases as well as for providing normal human tissue to conduct scientific research. A major obstacle for their application is that genomic instability arises in stem cells after prolonged cell culture. The most detrimental form of DNA damage is the DNA double-strand break (DSB), which is managed by cells through complex mechanisms, designated the DNA damage response. There are two major types of DSB repair; homologous …


Strategies To Employ Androstenediol To Reverse Steroid Inhibited Healing In A Rat Model Of Trauma, Francis Diskin Jul 2010

Strategies To Employ Androstenediol To Reverse Steroid Inhibited Healing In A Rat Model Of Trauma, Francis Diskin

Theses and Dissertations

Much of our current understanding regarding trauma, mechanisms of healing, and treatment strategies have evolved as a result of injuries suffered during armed conflict. While our understanding of these processes has advanced during and since these conflicts, treatment methods of traumatic wound healing have failed to progress significantly in the last forty years. The overall objective of this research was to test the hypothesis that the immune regulating hormone Androstenediol (AED) modulates the host’s immune system to promote wound healing under conditions where it has been inhibited by stress and infection. In an effort to characterize the effects of Androstenediol …


Pathogenic Role Of Phosphodiesterase Type 5 Upregulation In Cardiac Ischemia/Reperfusion Injury, Daniel Hobbs Jul 2010

Pathogenic Role Of Phosphodiesterase Type 5 Upregulation In Cardiac Ischemia/Reperfusion Injury, Daniel Hobbs

Theses and Dissertations

Phosphodiesterase Type 5 (PDE5) inhibitors are cardioprotective against ischemia/reperfusion (I/R) injury. However, it remains uncertain if I/R affects PDE5. We hypothesized that generation of reactive oxygen species (ROS) during I/R leads to upregulation of PDE5, which contributes to pathological changes following acute myocardial infarction (AMI). Adult male ICR mice were subjected to 30 minutes of in vivo or ex vivo I/R. To examine the role of ROS, a subset of hearts were perfused with 100 µM hydrogen peroxide (H2O2). Expression and activity of PDE5, pPDE5, and cGMP-dependent protein kinase (PKG) were measured by Western blots and spectrophotometric assay. The results …


Synthesis Of Glycolipids And Evaluation Of Their Nkt Cell Stimulatory Properties, Yang Liu Jul 2010

Synthesis Of Glycolipids And Evaluation Of Their Nkt Cell Stimulatory Properties, Yang Liu

Theses and Dissertations

Natural killer T (NKT) cells are a subset of T cells that modify a variety of immune responses. NKT cells recognize glycolipid antigen presented by a molecule called CD1d, a nonclassical antigen-presenting molecule. The best known subset of CD1d-dependent NKT cells expresses an invariant T cell receptor Vα (TCR-α) chain. These are referred to as type I or invariant NKT (iNKT) cells. When stimulated by a glycolipid, NKT cells rapidly release large amounts of cytokines. Cytokines released by NKT cells can induce either Th1 or Th2 responses. Th1 cytokines are effective in regulating bacterial, parasitic, and viral infections. But Th1 …


Targeting Complex Cyclic Peptides For Synthesis: The Celogentin And Theonellamide Families, Joshua Wayne Robinson Jun 2010

Targeting Complex Cyclic Peptides For Synthesis: The Celogentin And Theonellamide Families, Joshua Wayne Robinson

Theses and Dissertations

Celogentin C and theonellamide F are a class of natural products that have potential antimitotic behavior. They both contain interesting bicyclic structures with unusual linkages within a central moiety. Celogentin C's highly functionalized tryptophan moiety has two unusual linkages, a β-substituted Leu connection to the C6 of the indole structure that makes up the left-hand ring, and a τ-N connection of the imidazole to the C2 of the indole constructing the right-hand ring. This right-hand ring connection was solved via a novel oxidative coupling procedure developed in our group and the left-hand ring was initially constructed via a radical conjugated …


Novel Mechanism In Astrocyte Gene Regulation And Function, Sandeep Singh Jun 2010

Novel Mechanism In Astrocyte Gene Regulation And Function, Sandeep Singh

Theses and Dissertations

This dissertation sheds light on several novel mechanistic findings in astrocyte specific gene regulation and function by the NFI-X transcription factor which can be further extrapolated to astrocyte differentiation and glial tumor invasion. First, we cloned and analyzed human NFI-X3, a novel splice variant of the nfix gene, which contains a unique transcriptional activation (TA) domain completely conserved in primates. In contrast to previously cloned NFI-X1, overexpression of NFI-X3 potently activates NFI reporters, including GFAP reporter, in astrocytes and glioma cells. The expression of NFI-X3 is dramatically upregulated during the differentiation of neural progenitors to astrocytes and precedes the expression …


Celogentin C And Thioviridamide: Synthetic And Structural Studies, Dmitry Nikolayevich Litvinov Jun 2010

Celogentin C And Thioviridamide: Synthetic And Structural Studies, Dmitry Nikolayevich Litvinov

Theses and Dissertations

Project I Celogentin C, isolated by Kobayashi from the seeds of Celosia argentea in 2001 exhibits strong inhibitory behavior towards polymerization of tubulin – globular protein, which plays crucial role during the cell division cycle. We have attempted synthesis of the left-hand ring of celogentin C via the intramolecular alkylation and the Knoevenagel condensation strategies. Utilizing synthetic methodologies in the field of nitroacetyl chemistry, developed by Kornblum and Rajappa we have successfully prepared the intermolecular Knoevenagel condensation product – the late-stage precursor to the left-hand ring of celogentin C. Synthesis of this key intermediate subsequently led to the preparation of …


A Computational Biology Approach To The Analysis Of Complex Physiology: Coagulation, Fibrinolysis, And Wound Healing, Nathan Menke May 2010

A Computational Biology Approach To The Analysis Of Complex Physiology: Coagulation, Fibrinolysis, And Wound Healing, Nathan Menke

Theses and Dissertations

The birth of complexity research derives from the logical progression of advancement in the scientific field afforded by reductionist theory. We present in silico models of two complex physiological processes, wound healing and coagulation/fibrinolysis based on two common tools in the study of complex physiology: ordinary differential equations (ODE) and Agent Based Modeling (ABM). The strengths of these two approaches are well-suited in the analysis of clinical paradigms such as wound healing and coagulation. The complex interactions that characterize acute wound healing have stymied the development of effective therapeutic modalities. The use of computational models holds the promise to improve …


A Novel Role Of Sirt1 In Sildenafil Induced Cardioprotection In Mice, Mona Shalwala May 2010

A Novel Role Of Sirt1 In Sildenafil Induced Cardioprotection In Mice, Mona Shalwala

Theses and Dissertations

Phosphodiesterase-5 inhibitor, sildenafil (SIL) protects against myocardial ischemia/reperfusion (I-R) injury. We hypothesized that SIL-induced protection may be mediated through activation of SIRT1, an enzyme which deacetylates proteins involved in cellular stress response. Adult male ICR mice were treated with SIL (0.7mg/kg ip), Resveratrol (RSV) (5mg/kg ip) (positive control), or saline (0.2 ml ip). The hearts were harvested 24 h later and homogenized for SIRT1 activity analysis. Both SIL and RSV increased cardiac SIRT1 activity (P<0.001) as compared to Saline. Adult mouse ventricular cardiomyocytes pre-treated with either SIL or RSV (1µM) in vitro also upregulated SIRT1 activity (P<0.05). SIL also reduced infarct size following 30 min. ischemia and 24 h reperfusion in vivo. Sirtinol (5mg/kg in 10% DMSO, ip), a SIRT1 inhibitor abolished the infarct-limiting effect of SIL and RSV (P<0.001). In conclusion, activation of SIRT1 by SIL plays an essential role in cardioprotection against I-R injury.


Tied Together: A Molecular Role For Tie1 In Angiopoietin Tie2 Signaling, Tom Cm Seegar Apr 2010

Tied Together: A Molecular Role For Tie1 In Angiopoietin Tie2 Signaling, Tom Cm Seegar

Theses and Dissertations

The primary function of the vascular system is the maintenance of oxygen homeostasis for all metazoan tissue. Angiogenesis, the remodeling and maintenance of new blood vessels from an existing vessel, is primarily controlled through the endothelial specific receptor tyrosine kinase Tie2, and the orphan receptor tyrosine kinase, Tie1. Although these receptors share highly conserved, genetic and biochemical analysis has shown these receptors have distinct and essential roles in angiogenesis. Tie2 activation typically results in vessel stability and quiescences and has further been shown to interact with all four sub-types of the angiopoietin signaling factors, Ang1-4. Conversely, Tie1 is involved in …


Ribosomal Rna Mutations That Inhibit The Activity Of Transfer-Messenger Rna Of Stalled Ribosomes, Jacob N. Crandall Apr 2010

Ribosomal Rna Mutations That Inhibit The Activity Of Transfer-Messenger Rna Of Stalled Ribosomes, Jacob N. Crandall

Theses and Dissertations

In eubacteria, stalled ribosomes are rescued by a conserved quality-control mechanism involving transfer-messenger RNA (tmRNA) and its protein partner SmpB. Mimicking a tRNA, tmRNA enters stalled ribosomes, adds Ala to the nascent polypeptide, and serves as a template to encode a short peptide that tags the nascent protein for destruction. To further characterize the tagging process, we developed two genetic selections that link tmRNA activity to cell death. These negative selections can be used to identify inhibitors of tagging or to identify mutations in key residues essential for ribosome rescue. Little is known about which ribosomal elements are specifically required …


Role Of Members Of The Phosducin Gene Family In Protein Translation And Folding, Nana Sono-Koree Mar 2010

Role Of Members Of The Phosducin Gene Family In Protein Translation And Folding, Nana Sono-Koree

Theses and Dissertations

G proteins regulate various physiological processes by way of transducing a wide variety of signals ranging from hormonal to sensory stimuli. Malfunctions in G protein signaling lead to numerous diseases. G protein signaling begins with binding of a ligand to a G protein-coupled receptor resulting in a conformational change that leads to the exchange of a GDP for a GTP on G α. The GTP bound α subunit dissociates for its stable Gβγ dimer partner. G α-GTP and Gβγ control the activity of effector enzymes and ion channels that ultimately orchestrate the cellular response to stimulus. Current reports have shown …


The Asymmetric Phase-Transfer Catalyzed Alkylation Of Imidazolyl Ketones And Aryl Acetates And Their Applications To Total Synthesis, Michael Andrew Christiansen Mar 2010

The Asymmetric Phase-Transfer Catalyzed Alkylation Of Imidazolyl Ketones And Aryl Acetates And Their Applications To Total Synthesis, Michael Andrew Christiansen

Theses and Dissertations

Phase-transfer catalysts derived from the cinchona alkaloids cinchonine and cinchonidine are widely used in the asymmetric alkylation of substrates bearing moieties that resonance stabilize their enolates. The investigation of α-oxygenated esters revealed decreased α-proton acidity, indicating the oxygen's overall destabilizing effect on enolates by electron-pair repulsion. Alkylation of α-oxygenated aryl ketones with various alkyl halides proved successful with a cinchonidine catalyst, giving products with high yield and enantioselectivity. The resulting compounds were converted to esters through modified Baeyer-Villiger oxidation. Alkylation with indolyl electrophiles gave products that underwent decomposition under Baeyer-Villiger conditions. Alternative N-methylimidazolyl ketones were explored. Alkylated imidazolyl ketones, obtained …


Time-Resolved Infrared Spectroscopy And Density Functional Theory Study Of Weak Interactions Of Metal Carbonyls And Organic Solvents, Carolyn Evans Sheffield Mar 2010

Time-Resolved Infrared Spectroscopy And Density Functional Theory Study Of Weak Interactions Of Metal Carbonyls And Organic Solvents, Carolyn Evans Sheffield

Theses and Dissertations

Pulsed laser flash photolysis of M(CO)6 (M = Cr, W) in cyclohexane with a small amount of benzene results in three sequential reactions. The first is the photodissociation of the parent to yield a M(CO)5:C6H12 complex, which takes place faster than the time resolution of our experiments. The second reaction is the replacement of the cyclohexane ligand with benzene to form a M(CO)5:C6H6 complex, in which benzene is coordinated to the metal via one side of the ring. This complex then falls apart in solution as M(CO)5 coordinates with a trace impurity in the solution that is likely water. Kinetic …


Role Of Jak/Stat Pathway In The Pathogenesis Of Breast Cancer, Qifang Zhang Feb 2010

Role Of Jak/Stat Pathway In The Pathogenesis Of Breast Cancer, Qifang Zhang

Theses and Dissertations

The Jak/Stat signaling cascade mediates cell proliferation, differentiation, survival, apoptosis and immune responses. Aberrant activation of this pathway mediates neoplastic transformation and abnormal growth of many malignancies including breast cancer, the most common cancer among women, and the second leading cause of cancer deaths in women in United States. The mechanism by which the Jak/Stat pathway modulates the pathogenesis of breast cancer is unclear. This dissertation elucidates roles of Jak/Stat members that mediate the pathogenesis of breast cancer. For these studies, we used 4T1 mouse mammary tumor cells as a model which mimics human breast cancer. First, we investigated the …