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Articles 391 - 420 of 662

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Microfluidic Devices With Integrated Sample Preparation For Improved Analysis Of Protein Biomarkers, Pamela Nsang Nge Dec 2012

Microfluidic Devices With Integrated Sample Preparation For Improved Analysis Of Protein Biomarkers, Pamela Nsang Nge

Theses and Dissertations

Biomarkers present a non-invasive means of detecting cancer because they can be obtained from body fluids. They can also be used for prognosis and assessing response to treatment. To limit interferences it is essential to pretreat biological samples before analysis. Sample preparation methods include extraction of analyte from an unsuitable matrix, purification, concentration or dilution and labeling. The many advantages offered by microfluidics include portability, speed, automation and integration. Because of the difficulties encountered in integrating this step in microfluidic devices most sample preparation methods are often carried out off-chip. In the fabrication of micro-total analysis systems it is important …


Microfabrication, Characterization, And Application Of Carbon Nanotube Templated Thin Layer Chromatography Plates, And Functionalization Of Porous Graphitic Carbon, David S. Jensen Nov 2012

Microfabrication, Characterization, And Application Of Carbon Nanotube Templated Thin Layer Chromatography Plates, And Functionalization Of Porous Graphitic Carbon, David S. Jensen

Theses and Dissertations

This dissertation contains the following sections. Chapter 1 contains a detailed description of the theory of thin layer chromatography (TLC). Chapter 2 describes the benefits and practical considerations of elevated temperatures in liquid chromatography (LC). The porous graphitic carbon (PGC) I modified as part of my work is often used in elevated temperature LC. Chapter 3 shows a thermodynamic analysis of chromatographic retention at elevated temperature, and Chapter 4 contains a closer look at the van 't Hoff equation in LC and how it can be used in retention modeling. In Chapter 5, I describe a new procedure for microfabricating …


Deposition And Characterization Of Hydrophobic Coatings, Vipul Gupta Nov 2012

Deposition And Characterization Of Hydrophobic Coatings, Vipul Gupta

Theses and Dissertations

Hydrophobic coatings find application in various sectors of the economy including to electronics, textiles, optical devices, and in scientific and commercial equipment. These different applications demand that different hydrophobic coatings posses a range of properties that may include smoothness or roughness, thicknesses on the order of a monolayer or a micron, robustness or the ability to dissolve quickly, transparency or opacity, water resistance or water permeability, electrical conductivity, oleophobicity, etc. However, whatever the final/desired properties, deposition via dry-deposition processes offers significant advantages, including greater reproducibility, increased environmental friendliness, and cost effectiveness on an industrial scale. Herein I explore the chemical …


Mechanism Of Action Studies On A New Class Of Anticancer Nucleosides, Megan E. Browning Nov 2012

Mechanism Of Action Studies On A New Class Of Anticancer Nucleosides, Megan E. Browning

Theses and Dissertations

We have completed mechanism of action studies on a new class of anticancer nucleosides typified by a novel nucleoside discovered in our lab, MAP-870. In order to study the mechanism of MAP-870, several experiments were completed on a colorectal adenocarcinoma cell line, HT-29, including trypan blue cell count, sulforhodamine B assays, flow cytometry of cell cycle, propidium iodide incorporation, and phosphatidylserine externalization, Caspase-Glo3/7 assays, DNA fragmentation gel, cyclophilin A release gel, PAMPA, and confocal imaging. Sulforhodamine B assays show that MAP-870 does indeed cause growth inhibition and cell death in the model tested. PAMPA assays show that MAP-870 does not …


Gas Phase Characterization Of Supramolecules Using Cross-Sectional Areas By Fticr And Sustained Off-Resonance Irradiation Collision Induced Dissociation Techniques In A Fourier Transform Ion Cyclotron Resonance Mass Spectrometer, Fan Yang Aug 2012

Gas Phase Characterization Of Supramolecules Using Cross-Sectional Areas By Fticr And Sustained Off-Resonance Irradiation Collision Induced Dissociation Techniques In A Fourier Transform Ion Cyclotron Resonance Mass Spectrometer, Fan Yang

Theses and Dissertations

In my dissertation, I use a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FTICR-MS) to investigate supramolecules. Cross-sectional areas by Fourier transform ICR (CRAFTI), a novel technique for measurements of collision cross sections by FTICR, is demonstrated for the first time. The CRAFTI method measures the total "dephasing cross section" for removal of the ions from the coherent packet in the FTICR cell, including contributions not only from momentum transfer but also from reactive collisions including those leading to collisional dissociation. Experimental CRAFTI collision cross sections correlate linearly with theoretically computed results and with results obtained using ion mobility measurements. …


Flow Valve Diagnostics For Label-Free, Quantitative Biomarker Detection: Device Fabrication, Surface Modification, And Testing, Danielle Scarlet Mansfield Aug 2012

Flow Valve Diagnostics For Label-Free, Quantitative Biomarker Detection: Device Fabrication, Surface Modification, And Testing, Danielle Scarlet Mansfield

Theses and Dissertations

Diseases are often diagnosed by detection of disease-specific biomarkers in fluid samples. However, many state-of-the-art detection methods require a lab with complex machinery, trained operators, and/or lengthy analysis time. In contrast, point-of-care (POC) devices are brought to the patient's location, they are easy to use, and results are obtained almost immediately. Many current POC devices are too difficult to be used without a skilled assistant, and although many are able to detect analytes above a threshold value, they give little or no quantitative information. This work presents the development of polymer-based microfluidic devices capable of sensing and quantifying biomarkers in …


Synthesis And Biological Evaluation Of Various Derivatives Of A Broad-Spectrum Anticancer Nucleoside, Jadd R. Shelton Aug 2012

Synthesis And Biological Evaluation Of Various Derivatives Of A Broad-Spectrum Anticancer Nucleoside, Jadd R. Shelton

Theses and Dissertations

Recently the Peterson lab discovered a promising anticancer adenosine derivative-- 2´,3´-bis-O-tert-butyldimethylsilyl-5´-deoxy-5´-[N-(methylcarbamoyl)amino]-N6-(N-phenylcarbamoyl)adenosine. This compound showed selective toxicity against human colon cancer cells in vitro with LC50's = 6--10 µM. It was hypothesized that the lead compound exerted its cytotoxic effects by interacting with a protein kinase. A systematic Structure Activity Relationship (SAR) was undertaken in an attempt to increase the kinase-binding affinity of the lead compound. Many regions of the lead compound were examined: the N6-phenyl urea moiety, the 5´-N-methyl urea group, the 2´,3´-bis-O-TBS groups, the nucleobase, and the ribose sugar. Results of these studies produced some promising new derivatives. In …


Sorafenib Enhances Pemetrexed-Induced Cytotoxicity Through And Autophagy-Dependent Mechanism In Cancer Cells, Bareford Mary Aug 2012

Sorafenib Enhances Pemetrexed-Induced Cytotoxicity Through And Autophagy-Dependent Mechanism In Cancer Cells, Bareford Mary

Theses and Dissertations

Acquired cellular resistance to traditional chemotherapeutics is a common obstacle in the treatment of most cancer cell types. This resistance occurs as a result of changes in the underlying molecular mechanisms of disease progression. The development of novel chemotherapeutic approaches designed to enhance the efficacy of protypical anti-cancer drugs is important in order to overcome this issue. Such approaches will aid in understanding the biomolecular phenomena responsible for drug resistance and disease progression. Combining signaling pathway inhibitors has become an effective strategy for enhancing tumor cell death by targeting multiple pathways known to regulate cell survival. Pemetrexed, an FDA-approved anti-folate …


Spag16 Is A Bifunctional Gene Regulating Male Fertility, David R. Nagarkatti-Gude Jul 2012

Spag16 Is A Bifunctional Gene Regulating Male Fertility, David R. Nagarkatti-Gude

Theses and Dissertations

SPAG16 is the murine orthologue of Chlamydomonas reinhardtii PF20, a protein known to be essential to the structure and function of the “9 + 2” axoneme. The “9 + 2” axoneme provides the cytoskeletal core of all eukaryotic motile cilia and flagella. In Chlamydomonas, the Pf20 gene encodes a single protein present in the central pair of the axoneme. Loss of Pf20 prevents central pair assembly and results in flagellar paralysis. The murine Spag16 gene encodes two proteins. While 71 kDa SPAG16L is found in all murine cells with motile cilia or flagella, 35 kDa SPAG16S transcript and protein are …


Characterizing The Interaction Between Ve-Ptp, Tie2 And Ve-Cadherin, Sharif Ossai Muhammad Jul 2012

Characterizing The Interaction Between Ve-Ptp, Tie2 And Ve-Cadherin, Sharif Ossai Muhammad

Theses and Dissertations

Many signaling pathways have been shown to be involved in the formation of the vascular system. Among them are the endothelial specific receptor families such as VEGF, Ang/Tie, as well as other signaling pathways such as semaphorins, which are also involved, in axonal guidance. It is known that the interaction between receptor tyrosine kinase, Tie2, VE-Cadherin, and VE-PTP mediate endothelial cell quiescence and adhesion. However, the structural basis of these interactions is not well understood. The aim of our study is to characterize the binding interactions between these players. Another important part of our study is describing the cross-talk between …


The Synthesis And Structural Characterization Of Metal Oxide Nanoparticles Having Catalytic Applications, Stacey Janel Smith Jul 2012

The Synthesis And Structural Characterization Of Metal Oxide Nanoparticles Having Catalytic Applications, Stacey Janel Smith

Theses and Dissertations

Nanotechnology is blossoming into one of the premiere technologies of this century, but the key to its progress lies in developing more efficient nanosynthesis methods. Variations in synthetic technique, however, can cause variations in size, structure, and surface characteristics, thereby altering the physical properties and functionality of the particles. Careful structural characterizations are thus essential for understanding the properties and appropriate applications for particles produced by new synthetic techniques.In this work, a new ‘solvent-deficient’ method is presented for the synthesis of an unprecedentedly wide range of metal oxide nanomaterials including at least one metal oxide from each group in Groups …


Mda-7/Il-24; A Promising Cancer Therapeutic Agent, Hossein Hamed Jun 2012

Mda-7/Il-24; A Promising Cancer Therapeutic Agent, Hossein Hamed

Theses and Dissertations

Glioblastoma multiforme (GBM) is an aggressive cancer that affects millions of patients per year. Conventional therapies combining chemotherapeutic agents with radiation can only extend survival by a few months; therefore, there is a dire need for an effective means of treating this deadly disease. Melanoma differentiation-associated gene-7/interleukin-24 (mda-7/IL-24), currently in the early stages of FDA pre-IND drug trials, has proven to be an effective cancer specific cytokine, able to trigger the onset of mitochondrial dysfunction and/or autophagy. GBM’s have mutations that often result in the activation of cytoprotective cell signaling pathways, preventing cancer therapeutics and even MDA-7/IL-24 treatments from being …


Refining Vibrationally-Resonant Sum Frequency Generation Spectroscopy For Studies Of Interfacial Interactions, Alexander D. Curtis May 2012

Refining Vibrationally-Resonant Sum Frequency Generation Spectroscopy For Studies Of Interfacial Interactions, Alexander D. Curtis

Theses and Dissertations

Many phenomena of interest to science and engineering occur at interfaces; however, access to, or discrimination of, interfacial interactions has been challenging, especially at buried interfaces. Vibrationally resonant sum-frequency generation (VR-SFG) spectroscopy is a powerful tool for investigating the molecular structure of free or buried interfaces, but spectral analysis has relied on many assumptions. To claim accurate new insights, practitioners must be able to make unique determinations from the data without experimental artifacts affecting the final results. For example, two independent and overlapping studies for the polystyrene/air interface were carried out, but reported different surface structures. Initially, this difference was …


Novel Phosducin-Like Protein Binding Partners: Exploring Chaperone And Tumor Suppressor Protein Interactions, Amy Jetaun Gray Mar 2012

Novel Phosducin-Like Protein Binding Partners: Exploring Chaperone And Tumor Suppressor Protein Interactions, Amy Jetaun Gray

Theses and Dissertations

Many proteins cannot fold into their native state without the assistance of one or more molecular chaperones. Chaperonins are an essential class of chaperones that provide an isolated chamber for proteins to fold. CCT, a group II chaperonin found in eukaryotes assists in the folding of actins, tubulins, and many other cellular proteins. PhLP1 is a member of the phosducin protein family that assists CCT in the folding of Gβ and its subsequent assembly with Gγ. However, previous studies have not addressed the scope of PhLP1 and CCT-mediated Gβγ; assembly. The data presented in Chapter 2 shows that PhLP1 plays …


Follicular Dendritic Cells, Human Immunodeficency Virus Type 1, And Alpha 1 Antitrypsin, Xueyuan Zhou Mar 2012

Follicular Dendritic Cells, Human Immunodeficency Virus Type 1, And Alpha 1 Antitrypsin, Xueyuan Zhou

Theses and Dissertations

HIV/AIDS is raging and causing millions of deaths around the world. The major challenge in treating HIV/AIDS is the establishment of HIV reservoirs where the viruse escapes both drug and immune system attempts at eradication. Throughout the course of HIV/AIDS, productive HIV infection occurs primarily in the lymphoid follicles or germinal centers (GC) surrounding follicular dendritic cells (FDC). In the GCs, FDCs trap and maintain infectious HIV for years and provide these infectious viruses to the host cells. FDCs also attract B and T cells into the GCs and increase the ability of CD4+ T cells to be infected. Additionally, …


Optical And Mass Spectrometric Studies Of A Helium Dielectric-Barrier Atmospheric-Pressure Plasma Jet Used As An Ambient Desorption Ionization Source, Matthew Spencer Heywood Mar 2012

Optical And Mass Spectrometric Studies Of A Helium Dielectric-Barrier Atmospheric-Pressure Plasma Jet Used As An Ambient Desorption Ionization Source, Matthew Spencer Heywood

Theses and Dissertations

Recently there has been a surge in the field of mass spectrometry centered around the concept of rapid analysis of target analytes with minimal or no sample preparation. The target analyte undergoes desorption from its surface of origin and is subsequently ionized under ambient conditions. The technique is termed ambient desorption/ionization mass spectrometry (ADI-MS). Since the introduction of ADI-MS in 2004, there has been an explosion of research based around the development of novel ambient desorption/ionization (ADI) sources with the capability of desorbing and ionizing a variety of target analytes from various sampling surfaces. One type of ADI source uses …


Dynamics Of The Solvent Exchange Reaction Of Weakly Bound Organic Solvents To Group 6 Transition Metal Carbonyls And The Molybdenum Hexacarbonyl Mediated Pauson-Khand Reaction, Richard J. Gates Feb 2012

Dynamics Of The Solvent Exchange Reaction Of Weakly Bound Organic Solvents To Group 6 Transition Metal Carbonyls And The Molybdenum Hexacarbonyl Mediated Pauson-Khand Reaction, Richard J. Gates

Theses and Dissertations

Many organometallic reactions are solvent-dependent, suggesting solvent molecules interact with reaction intermediates. Studies of the solvent exchange reaction of group 6 transition metal carbonyls with moderately binding ligands have provided insight into these interactions, however, studies of the mechanism for this reaction with weakly binding ligands have not been performed. Experiments were conducted on the nanosecond time scale in methylcyclohexane over the temperature range of 4 to 44 °C using Step Scan FTIR (SS FTIR) spectroscopy with weakly binding ligands benzene and mesitylene. Upon photolysis of the metal hexacarbonyls, the kinetically favored product (M(CO)5(solv)), decays following pseudo-first-order kinetics to the …


Opposing Roles Of The Μ-Opioid And Nociceptin/Orphanin Fq Receptors In Oligodendrocyte Development And Myelination, Allison Vestal-Laborde Jan 2012

Opposing Roles Of The Μ-Opioid And Nociceptin/Orphanin Fq Receptors In Oligodendrocyte Development And Myelination, Allison Vestal-Laborde

Theses and Dissertations

While the classical function of myelin is to facilitate saltatory conduction, this membrane and the myelin-making oligodendrocytes (OLGs) are now recognized as regulators of plasticity and remodeling in the central nervous system (CNS). Thus, OLG maturation and myelination are highly vulnerable processes along CNS development. We previously showed that rat brain myelination is altered by perinatal exposure to buprenorphine, an opioid analogue in clinical trials for the treatment of pregnant opioid addicts. We now found that the in vivo effects on myelination could result from direct alteration in the balance between μ-opioid receptor (MOR) and nociceptin/orphanin FQ receptor (NOPR) activities …


Non-Canonical Roles For Stat1 And Stat2 In Mitochondrial Biogenesis And Fasting Homeostasis., Jennifer Sisler Jan 2012

Non-Canonical Roles For Stat1 And Stat2 In Mitochondrial Biogenesis And Fasting Homeostasis., Jennifer Sisler

Theses and Dissertations

The signal transducer and activator of transcription 1 (STAT1) and 2 (STAT2) are primarily activated by interferons and play a central role in orchestrating responses to a variety of pathogens by activating the transcription of nuclear encoded genes that mediate antiviral, antigrowth and immune surveillance responses. In addition to their nuclear effects, we report that STAT1 and STAT2 inhibit the expression of mitochondrial encoded mRNAs by activating type I interferons (IFNβ) under basal conditions. STAT1-/- livers also exhibit elevated levels of nuclear encoded components of the electron transport chain (ETC). Treatment of wild-type mice with IFNβ inhibits both mitochondrial and …


Role Of Lysophosphatidic Acid In Regulation Of Cancer Cell Metabolism, Abir Mukherjee Jan 2012

Role Of Lysophosphatidic Acid In Regulation Of Cancer Cell Metabolism, Abir Mukherjee

Theses and Dissertations

The simplest phospholipid, lysophosphatidic acid (LPA), is a heat stable component of serum known for its proliferative and migratory activities in cancer cells. Strong evidence suggests that LPA production and expression of its receptors are dysregulated in multiple human malignancies. The mechanism behind LPA-mediated tumor cell growth and oncogenesis remains poorly understood. In this thesis project I used ovarian and other cancer cells as a model system to examine the hypothesis that LPA present in the tumor microenvironment is a pathophysiological determinant of hyperactive de novo lipogenesis and aerobic glycolysis, two hallmarks of cancer cells. We demonstrated that LPA induced …


Crosstalk Between Lysophospatidic Acid (Lpa) And Transforming Growth Factor Beta (Tgfβ) In Breast And Ovarian Cancer Cells, Jinhua Wu Jan 2012

Crosstalk Between Lysophospatidic Acid (Lpa) And Transforming Growth Factor Beta (Tgfβ) In Breast And Ovarian Cancer Cells, Jinhua Wu

Theses and Dissertations

Lysophosphatidic acid (LPA) and transforming growth factor beta (TGFβ) are platelet-derived intercellular mediators of cell proliferation and motility. LPA is a general growth, survival and motility-stimulating factor in mammalian cells. TGFβ prevents proliferation of normal epithelial cells. However, the growth-inhibitory effect of TGFβ is lost or reduced in most malignant cells. Instead, TGFβ promotes migration and invasion of advanced cancer cells. Since LPA and TGFβ are both present in the blood and tumor microenvironments, we were interested in signal integration and functional outcomes in malignant epithelial cells in an LPA and TGFβ co-stimulatory context. In a subset of breast and …


The Role Of R7 Regulators Of G Protein Signaling In The Retina, Hoon Shim Jan 2012

The Role Of R7 Regulators Of G Protein Signaling In The Retina, Hoon Shim

Theses and Dissertations

The R7 regulators of G protein signaling (R7 RGS), namely RGS6, RGS7, RGS9 and RGS11, are expressed in the retina along with its binding partner Gβ5. The RGS9-1 isoform is expressed only in retinal photoreceptors and rate-limits the recovery of rod phototransduction by acting as a member of the transducin GAP complex (RGS9-1/Gβ5L/R9AP). The Gβ5L isoform is also only expressed in retinal photoreceptors and acts by stabilizing the GAP complex. The Gβ5S isoform differs from Gβ5L by the absence of exon 1 due to alternative splicing and is expressed in many other retinal cells. Gβ5L is barely detectable in RGS9-/- …


Identifying Sortase A Variants With Higher Catalytic Effeciency, Muna Suliman Jan 2012

Identifying Sortase A Variants With Higher Catalytic Effeciency, Muna Suliman

Theses and Dissertations

In the past two decades, the field of protein engineering has evolved rapidly to include new genetic and chemical techniques to alter protein function. Protein engineering seeks to improve enzyme properties through powerful methods that specifically incorporate novel or improved function in proteins. One such method is protein ligation, which is used to selectively link synthetic and recombinant polypeptides. Due to the limitations of current protein labeling techniques, simple site-specific modification methods remain in high demand. Use of enzyme-based labeling has been the focus of various studies because of its substrate specificity. Sortase-mediated transpeptidation is one approach that has been …


Design And Synthesis Of Cationic Steroid Antimicrobial Compounds, Synthesis Of Glycolipids Recognized By Natural Killer T Cells And Development Of Tlr-1, Tlr-6 Heterodimer Binders And Studies Of Their Immunology Activities, Yanshu Feng Dec 2011

Design And Synthesis Of Cationic Steroid Antimicrobial Compounds, Synthesis Of Glycolipids Recognized By Natural Killer T Cells And Development Of Tlr-1, Tlr-6 Heterodimer Binders And Studies Of Their Immunology Activities, Yanshu Feng

Theses and Dissertations

Cationic steroid antimicrobial agents (CSAs) are a family of bile acid derivatives. These compounds are amphiphilic and mimic endogenous antimicrobial peptides. The antimicrobial activities of CSA-13 have been investigated and due to portent bactericidal activities and low toxicity, a large amount of CSA-13 is demanded for clinic trails and other antimicrobial applications. During our studies, we optimized the synthetic route of CSA-13, so that it can be prepared at the kilogram, even in tons scale. We investigated three routes and one of them is suitable for industry, because only recrystallization is needed in the synthesis. Natural killer T cells (NKT …


Influence Of Weak Interactions On Supramolecular Binding: Characterization Of Cucurbituril Complexes With Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Ruijan Shi Dec 2011

Influence Of Weak Interactions On Supramolecular Binding: Characterization Of Cucurbituril Complexes With Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, Ruijan Shi

Theses and Dissertations

This thesis focuses on using mass spectrometry-based techniques for characterizing the structure and behavior of cucurbituril complexes in the gas phase. Both solvent and counter ion effects can be completely eliminated in the gas phase and the intrinsic interactions in the system are directly shown in the experimental results. Chapter 1 introduces the structures, properties and host-guest chemistry of cucurbituril, and FTICR mass spectrometry including instrumentation, performance and working principles. Two mass spectrometry-based methods for supramolecular characterization, sustained off-resonance irradiation collision induced dissociation (SORI CID) and ion molecule equilibrium measurements, are also discussed in this chapter. Chapter 2 characterizes the …


Mechanism Of G Protein Beta-Gamma Assembly Mediated By Phosducin-Like Protein 1, Chun Wan Jeffrey Lai Dec 2011

Mechanism Of G Protein Beta-Gamma Assembly Mediated By Phosducin-Like Protein 1, Chun Wan Jeffrey Lai

Theses and Dissertations

G-protein coupled receptor signaling (GPCR) is essential for regulating a large variety of hormonal, sensory and neuronal processes in eukaryotic cells. Because the regulation of these physiological responses is critical, GPCR signaling pathways are carefully controlled at different levels within the cascade. Phosducin-like protein 1 (PhLP1) can bind the G protein βγ dimer and participate in GPCR signaling. Recent evidence has supported the concept that PhLP1 can serve as a co-chaperone of the eukaryotic cytosolic chaperonin complex CCT/TRiC to mediate G βγ assembly. Although a general mechanism of PhLP1-mediated G βγ assembly has been postulated, many of the details about …


Regulation Of High Light Responses In Synechocystis Sp. Pcc6803, Waqar Majeed Dec 2011

Regulation Of High Light Responses In Synechocystis Sp. Pcc6803, Waqar Majeed

Theses and Dissertations

Cyanobacteria have evolved various acclimation mechanisms to enable them to thrive under harsh environmental conditions. There are a total of more than 80 sensory kinases and response regulators on the genome of the cyanobacterium Synechocystis sp. PCC 6803, which coordinate the molecular responses to changes in environmental conditions. However, it is not clearly understood how these regulators control the stress-responsive genes. This dissertation focuses on analysis of the functions of two regulators, RpaA and DspA, by targeted mutagenesis. Upon deletion of RpaA, a significant reduction in chlorophyll fluorescence from photosystem I at 77K was observed in whole cells and the …


Characterizing The Phosphorylation State Of Tie2 Using Sh2 Domain Fusion Proteins, Kenneth Yuth Dec 2011

Characterizing The Phosphorylation State Of Tie2 Using Sh2 Domain Fusion Proteins, Kenneth Yuth

Theses and Dissertations

The cardiovascular system develops through two distinct processes in embryogenesis: vasculogenesis, whereby the primary plexus in the heart is formed along with embryonic and extraembryonic vasculature, and angiogenesis, which begins after vasculogenesis and results in the refinement and maturation of the branched vessel system. In pathological angiogenesis, tumors expand by releasing pro-angiogenic factors in response to hypoxic conditions. The Tie receptors, Tie1 and Tie2, are receptor tyrosine kinases that are integral to angiogenic pathways. A family of Angiopoietins, Ang1-4, have been shown to act as ligands for Tie2, of which Ang1 and Ang2 are best characterized. Activation of the receptor …


Total Synthesis Of 4'-Ester Resveratrol Analogs And 8.9-Amido Geldanamycin Analog And Toward The Total Synthesis Of (-)-Englerin A, Yong Wang Oct 2011

Total Synthesis Of 4'-Ester Resveratrol Analogs And 8.9-Amido Geldanamycin Analog And Toward The Total Synthesis Of (-)-Englerin A, Yong Wang

Theses and Dissertations

Total Synthesis of 4'-ester Resveratrol Analogs and 8, 9-amido Geldanamycin Analog and toward the Total Synthesis of (-)-Englerin A Yong Wang Department of Chemistry and Biochemistry, BYU Doctor of Philosophy The phytoalexin resveratrol and its 4'-ester analogs have been prepared with a decarbonylative Heck reaction. The deprotecting step has been modified and improved to increase yield and avoid chromatography. A set of resveratrol analogs and resveratrol have been tested with melanoma and pancreatic cell assays. The 8, 9-amido Geldanamycin analog has been synthesized with a convergent route, involving 28 simplified steps in its longest linear sequence. Synthetic methodologies, such as …


Identification And Characterization Of A Novel Thermohalophilic Esterase From The Red Sea: Atlantis Ii Brine Pool, Yasmine Mustafa Mohamed Oct 2011

Identification And Characterization Of A Novel Thermohalophilic Esterase From The Red Sea: Atlantis Ii Brine Pool, Yasmine Mustafa Mohamed

Theses and Dissertations

Industrial (white) biotechnology poses an increasing demand for novel biocatalysts that are robust under a wide range of conditions. Traditionally, biocatalysts were isolated from cultured isolates, however, less than 1% of microorganisms are culturable. Therefore, it became evident that the unculturable majority holds a great potential for the discovery of novel biocatalysts. Metagenomics is an invaluable tool for accessing the genomes of the uncultured majority and has led to the isolation of a large number of biocatalysts from various environments. Extreme environments such as hydrothermal vents, brine pools and glaciers, are an attractive source for biocatalysts. Biocatalysts from these environments …