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A Network View On Neurodegenerative Disorders, Sreedevi Chandrasekaran May 2013

A Network View On Neurodegenerative Disorders, Sreedevi Chandrasekaran

Theses and Dissertations

Neurodegeneration is a chronic, progressive and debilitating condition that affects majority of the World's elderly population who are at greater risk. Numerous scientific studies suggest that there could be a common underlying molecular mechanism that promotes the degeneration and the subsequent neuronal loss, however so far the progress in this direction is rather limited. Abnormal protein misfoldings, as well as protein plaque formations in the brain, are some of the hallmark characteristic features of neurodegenerative disorders (NDDs). Genetic and environmental factors, oxidative stress, excessive reactive oxygen species formation, mitochondrial dysfunction, energy depletion and autophagy disruption etc. are some of the …

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Myelin Is Not Required For Maintenance Of The Axon Initial Segment, Anna Josephson May 2013

Myelin Is Not Required For Maintenance Of The Axon Initial Segment, Anna Josephson

Theses and Dissertations

Axonal pathology is a major contributor to impaired motor, sensory and cognitive dysfunction associated with multiple sclerosis particularly with the progressive forms of the disease. However, the early pathologic events responsible for axonal deterioration remain unclear. It is well recognized that maintaining proper axonal function is intimately related to proper establishment and maintenance of axonal domains such as the node of Ranvier and the axon initial segment (AIS). Numerous laboratories, including ours, have investigated the mechanisms that regulate node of Ranvier formation and maintenance. These studies have shown that node of Ranvier formation and maintenance require myelin contact. Interestingly, many …

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Opportunities For The Sustainable Use Of The Camel In Qatar, Corby Jayne Elford May 2013

Opportunities For The Sustainable Use Of The Camel In Qatar, Corby Jayne Elford

Theses and Dissertations

In the course of the modernization of Qatar, the need for camels has greatly diminished; herds have reduced in numbers and are now confined to enclosures. Overall, neglect of this valuable resource means that the camel is threatened with extinction. Currently, there is a need to address problems about sustainable development in Qatar by taking actions such as investing in the existing natural heritage to develop the use of indigenous animals like the camel. Through a review of past and present use of the native dromedary, a new type of sustainable agritourism will be developed that will provide a type …

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Phylometagenomics: A New Framework For Uncovering Microbial Community Diversity, Christopher J. Friedline May 2013

Phylometagenomics: A New Framework For Uncovering Microbial Community Diversity, Christopher J. Friedline

Theses and Dissertations

Microbial communities are recognized as major drivers of global biogeochemical processes. However, the genetic diversity and composition, as well as processes leading to the origin and diversification of these communities in space and time, are poorly understood. Character- ization of microbial communities using high-throughput sequencing of 16S tags shows that Operational Taxonomic Unit (OTU) abundances can be approximated by a gamma distribu- tion, which suggests structuring around small numbers of highly abundant OTUs and a large proportion of rare OTUs. The current methods used to characterize how communities are structured rely on multivariate statistics, which operate on pair-wise distance matrices. …

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Differential Effects Of Growth Factors On Glycolysis In Ovarian Cancer Cells, Fang Yuan May 2013

Differential Effects Of Growth Factors On Glycolysis In Ovarian Cancer Cells, Fang Yuan

Theses and Dissertations

Lysophosphatidic acid (LPA), a naturally-occurring, simple phospholipid, is present at elevated levels in the blood and ascites of ovarian cancer patients. LPA is a ligand of seven cell surface G protein-coupled receptors. It has been known as an oncogenic growth factor in ovarian cancer and other types of human malignancies. However, the precise biological functions of LPA in ovarian oncogenesis remain to be fully elucidated. Our laboratory is interested in studying the potential role of LPA, as a tumor microenvironment factor, in regulation of cancer cell metabolism. A fundamental change associated with most cancer is the switch of glucose metabolism …

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Inclusion Of African American Vernacular English In The Classroom, Chris Roye-Gill Apr 2013

Inclusion Of African American Vernacular English In The Classroom, Chris Roye-Gill

Theses and Dissertations

A plethora of research exists citing the poor academic performance of African American children in this country (D'Angiulli, Siegel, & Maggi, 2004; Labov, 1971, 1995; Miranda, Webb, Brigman, & Peluso, 2007). A large amount of the research is specific to reading deficits identified with African American students. Students who are successful readers are also successful in the other content areas. Lytel and Botel (1990) along with the Pennsylvania Department of Education (PDE, 2009) contend that literacy encompasses reading, writing, speaking, and understanding. They go further to say that if one is to acquire these skills, learning has to be relevant. …

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Comparison Of Injection Discomfort And Anesthetic Duration Of Plain Polocaine Versus Epinephrine Containing Articaine And Lidocaine, Dana Doan Apr 2013

Comparison Of Injection Discomfort And Anesthetic Duration Of Plain Polocaine Versus Epinephrine Containing Articaine And Lidocaine, Dana Doan

Theses and Dissertations

Purpose: To determine possible differences in the pain level and soft tissue anesthesia duration of plain polocaine versus epinephrine-containing articaine and lidocaine during intraoral injections. Methods: Forty-eight subjects received plain polocaine and one epinephrine-containing anesthetic. Injections were randomized according to the first injection a)left or right buccal sulcus and b)epinephrine or not. The second injections were the opposite conditions. Subjects then recorded discomfort on a VAS and the time anesthesia wore off. Result: The second injection’s pain rating was influenced by the first. This carry-over effect makes it impossible to analyze all of the data. An analysis of the first …

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Investigating The Potential Applications Of A Raman Tweezer System, John Wray Apr 2013

Investigating The Potential Applications Of A Raman Tweezer System, John Wray

Theses and Dissertations

This thesis describes the construction of an Optical Tweezer apparatus to be used in conjunction with a confocal Raman spectrometer. The tweezer utilizes an infrared (λ=1064 nm) laser directed into an inverted microscope with NA=1.4 oil immersion 100x objective lens that strongly focuses the laser light into a sample to function as a single-beam gradient force trap. The long term goal of this research program is to develop a single molecule Raman tweezers apparatus that allows one to control the position of a Raman nanoplasmonic amplifier. This thesis describes the construction of the Raman tweezer apparatus along with several Raman …

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Microbial Dna Receptor Expression In Chronic Periodontitis, Stephanie Voth Apr 2013

Microbial Dna Receptor Expression In Chronic Periodontitis, Stephanie Voth

Theses and Dissertations

AIM: The aim of this study was to determine the expression of microbial nucleic acid receptors including Toll like receptor 9 “TLR-9”, DNA-dependent activator of interferon-regulatory factors “DAI” and absent in melanoma “AIM-2” in chronic periodontitis (P) versus healthy (H) tissues. METHODS: 33 chronic periodontitis (P) and 27 periodontally-healthy (H) gingival biopsies were included. The gene and protein expression for each receptor was determined using real-time quantitative PCR and immunohistochemistry. RESULTS: Our results revealed statistically significant up-regulation of TLR-9 (p<0.006) and DAI (p<0.001) gene expression in P tissues compared to H sites. We were also able to demonstrate significant correlation among three DNA receptors (p<0.05). Immunohistochemistry further confirmed the expression of DNA sensors in gingival tissues. CONCLUSION: This study highlights a possible role for nucleic acid sensing in periodontal inflammation. Further investigations will determine whether cytoplasmic receptors and their ligands can be targeted to improve clinical outcomes in periodontitis.

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Bioinformatics Approach To Probe Protein-Protein Interactions: Understanding The Role Of Interfacial Solvent In The Binding Sites Of Protein-Protein Complexes;Network Based Predictions And Analysis Of Human Proteins That Play Critical Roles In Hiv Pathogenesis., Mesay Habtemariam Apr 2013

Bioinformatics Approach To Probe Protein-Protein Interactions: Understanding The Role Of Interfacial Solvent In The Binding Sites Of Protein-Protein Complexes;Network Based Predictions And Analysis Of Human Proteins That Play Critical Roles In Hiv Pathogenesis., Mesay Habtemariam

Theses and Dissertations

The thesis work contains two projects under the same umbrella. The first project is to provide a detailed analysis on the behavior of interfacial water molecules at protein-protein complexes, in this case focusing on homodimeric complexes, and to investigate their effect with respect to different residue types. For that reason the homodimeric data-set, which includes high-resolution (≤ 2.30 Å) X-ray crystal structures of 252 (140 Biological & 112 Non-biological) protein complexes was chosen to explore fundamental differences between interfaces that Nature has “engineered” vs. compared to interfaces found under man-made conditions. The data set was comprised of 5391 water molecules …

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Influence Of Facial Profile On Social Perceptions: A 3d Video Imaging Study., Lisa Babb Apr 2013

Influence Of Facial Profile On Social Perceptions: A 3d Video Imaging Study., Lisa Babb

Theses and Dissertations

The purpose of this study was to evaluate the influence of facial convexity on the perception of social attributes in a young adult population. Nine models were asked to pose for a 3 dimensional photograph that was then modified to represent ideal, retrognathic, and prognathic facial convexity angles. Survey evaluators were shown digital videos of models with ideal and non-ideal profiles and asked to rate their perception of the following 4 social attributes: intelligence, athleticism, popularity, and leadership ability using a visual analog scale. Results gathered from 271 evaluators showed that the model images with ideal facial convexity angles were …

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Chemoelectromechanical Actuation In Conducting Polymer Hybrid With Bilayer Lipid Membrane, Hao Zhang Apr 2013

Chemoelectromechanical Actuation In Conducting Polymer Hybrid With Bilayer Lipid Membrane, Hao Zhang

Theses and Dissertations

Biological and bio-inspired systems using ion transport across a membrane for energy conversion has inspired recent developments in smart materials. The active mechanism in bioderived materials is ion transport across an impermeable membrane that converts electrochemical gradients into electrical and mechanical work. In addition to bioderived materials, ion transport phenomenon in electroactive polymers such as ionomeric and conducting polymers produces electromechanical coupling in these materials. Inspired by the similarity in transduction mechanism, this thesis focuses on integrating the ion transport processes in a bioderived material and a conducting polymer for developing novel actuation systems. The integrated membrane has a bilayer …

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Reforestation Of Red Spruce (Picea Rubens) On The Cheat Mountain Range, West Virginia, Justin Madron Apr 2013

Reforestation Of Red Spruce (Picea Rubens) On The Cheat Mountain Range, West Virginia, Justin Madron

Theses and Dissertations

The (Plethodon nettingi) Cheat Mountain Salamander is a rare and endangered species that relies heavily on (Picea rubens) Red Spruce for habitat. P. rubens communities on the Cheat Mountain range in West Virginia have been disturbed by fires and logging, and regeneration of P. rubens stands are central to the survival of the P. netting. A supervised and unsupervised landscape classification of three Landsat images over the past 26 years was conducted to analyze change in P. rubens communities on Cheat Mountain Range. Change detection results revealed that from 1986-2012 a 52% growth increase of P. rubens stands, 18% loss, …

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The Economy Of Indifference, Nicholas Irzyk Apr 2013

The Economy Of Indifference, Nicholas Irzyk

Theses and Dissertations

The following monologue examines the personal, cultural and ethical viability of abstraction in a contemporary painting practice, conducted on the eve of my thesis exhibition.

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Mimicking The Mechanical Behavior Of Advancing Disc Degeneration Through Needle Injections, Jeremy S. Alsup Apr 2013

Mimicking The Mechanical Behavior Of Advancing Disc Degeneration Through Needle Injections, Jeremy S. Alsup

Theses and Dissertations

Objective - To investigate the effects of injected protease solution on the mechanical advancement of disc degeneration, and to establish test protocol for future pre-clinical validation of spinal arthroplasty devices. The hypothesis that injection of a protease into a cadaveric lumbar disc will mimic advanced degeneration mechanics was the subject of this study. Summary of Background Information - Spinal disc degeneration is a universal condition that progresses in adults due to aging, disease, or injury. Stages of disc degeneration have been categorized in cadaver specimens, with each degeneration level exhibiting characteristic changes in flexibility parameters. Spinal disc tissue can be …

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The Role Of Camk-Ii In Skeletal Muscle Function And Swimming Behavior In Zebrafish, Minh Nguyen Apr 2013

The Role Of Camk-Ii In Skeletal Muscle Function And Swimming Behavior In Zebrafish, Minh Nguyen

Theses and Dissertations

Previous research showed mutations in muscle sarcoplasmic reticulum-bound calcium handler proteins cause swimming defects in embryonic zebrafish. CaMK-II is a highly conserved Ca2+/calmodulin-dependent protein kinase expressed in all vertebrates has been defined to activate and inactivate multiple Ca2+ handler proteins involved in excitation- contraction coupling and relaxation of cardiac and skeletal muscle. In this study, evidence is provided through pharmacological and genetic intervention that CaMK-II inhibition and overexpression causes swimming defects, particularly response to stimuli and swimming ability, reinforced by immunolocalization of skeletal muscle. Transient CaMK-II inactivation does not have any long-term defects to swimming behavior. Overexpression of wild-type, constitutively …

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Chromosome-Specific Telomere Length In Women With Breast Cancer: Their Relationship To Chemotherapy And Acquired Psychoneurological Symptoms, Areej Alhareeri Apr 2013

Chromosome-Specific Telomere Length In Women With Breast Cancer: Their Relationship To Chemotherapy And Acquired Psychoneurological Symptoms, Areej Alhareeri

Theses and Dissertations

Breast cancer (BC) is one of the most common diagnosed malignancies in females. Although 90% of early diagnosed women are expected to survive for at least 5 years, their quality of life is adversely affected by a cluster of symptoms which we collectively named “psychoneurological symptoms’’ (PN). Given that acquired telomere attrition has been speculated to be a causal factor in chronic diseases and the lack in the literature of mechanisms giving rise to PN symptoms, this study was performed to assess telomere length using a chromosome-specific telomere assay before receiving chemotherapy and at the first chemotherapy. We showed significant …

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A Positive Dimension: Exploring Factors That Enhance Utilization Of And Adherence To Prevention Of Mother-To-Child Transmission (Pmtct) Of Hiv Services In An Urban Setting In Kenya, Lydia Murithi Apr 2013

A Positive Dimension: Exploring Factors That Enhance Utilization Of And Adherence To Prevention Of Mother-To-Child Transmission (Pmtct) Of Hiv Services In An Urban Setting In Kenya, Lydia Murithi

Theses and Dissertations

Despite expansive scale-up of prevention of mother-to-child transmission (PMTCT) of HIV services in Kenya over the last decade, Kenya remains one of the countries contributing high numbers of children living with HIV globally and among the 22 PMTCT global plan priority countries. Using a mixed methods approach this study examined enabling factors –individual, social and structural – that enhance utilization of and adherence to PMTCT services in a plural urban setting in Kenya. The study was conducted from October-December of 2012 at St. Mary’s Mission Hospital, Lang’ata. HIV-positive birthmothers whose infants were HIV-negative at the time of the study were …

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Modification Of Nanostructures Via Laser Processing, Louis Franzel Apr 2013

Modification Of Nanostructures Via Laser Processing, Louis Franzel

Theses and Dissertations

Modification of nanostructures via laser processing is of great interest for a wide range of applications such as aerospace and the storage of nuclear waste. The primary goal of this dissertation is to improve the understanding of nanostructures through two primary routes: the modification of aerogels and pulsed laser ablation in ethanol. A new class of materials, patterned aerogels, was fabricated by photopolymerizing selected regions of homogeneous aerogel monoliths using visible light. The characterization and fabrication of functionally graded, cellular and compositionally anisotropic aerogels and ceramics is discussed. Visible light was utilized due to it’s minimal absorption and scattering by …

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The Effects Of Tarsh Overexpression On Lung Carcinomas, Young Kim Apr 2013

The Effects Of Tarsh Overexpression On Lung Carcinomas, Young Kim

Theses and Dissertations

Lung cancer arises from epithelial cells that line the air passages of the lungs. It is the second most common malignancy in the United States; trends suggest that over 228,000 new patients will be diagnosed with lung cancer in 2013. Due to the fact that lung cancer is highly aggressive, it has proven difficult to control. The 5-year survival rate has been shown to be only 15.9%, despite the advances made in terms of diagnosis and treatment. Therefore, we are faced with the problem of finding more effective methods that allow for an earlier diagnosis and the improved treatment of …

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Structural And Functional Characterization Of Sortase A, Vishaka Santosh Apr 2013

Structural And Functional Characterization Of Sortase A, Vishaka Santosh

Theses and Dissertations

Sortases have been known to be essential in Gram-positive bacteria for attaching proteins onto the peptidoglycan layer of the bacterium. Sortase A has been found to be useful as a “molecular stapler”, although; in vivo, the enzyme is responsible for attaching proteins to the peptidoglycan layer of Gram-positive bacteria. It accomplishes both of these tasks by joining two proteins together via an LPXTG sorting sequence. The enzyme has been proven to be very useful in attaching any two proteins together without worrying about recombinant techniques to generate the fusion protein. The problem with this enzyme is that the catalytic diad, …

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Water | Desire: Design Of A Responsible Urban Retreat In Georgetown, Washington, Dc, Tanya Zimmerli Apr 2013

Water | Desire: Design Of A Responsible Urban Retreat In Georgetown, Washington, Dc, Tanya Zimmerli

Theses and Dissertations

The design of an urban retreat within an industrial building in Georgetown, DC provides an opportunity to experience water in the built environment. The location of the building between two bodies of water—the Chesapeake and Ohio Canal and the Potomac River—creates an opportunity to connect water and the visitors. Management of the water to ensure responsible resource use was researched and accommodated in the design. Water is further used to shape the space and the moods created by the volumes, materials and finishes. The final project provides a luxurious shower and locker room, a series of pools, and a tea …

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Catherine Opie's Domestic Series, Sara Harney Apr 2013

Catherine Opie's Domestic Series, Sara Harney

Theses and Dissertations

American photographer Catherine Opie combines portraiture and documentary photography in her photographic series titled Domestic. At the center of this series lies the idea of community and the question of how community is constructed, a theme which unites Opie’s seemingly disparate bodies of work. Domestic depicts lesbians from across the United States in scenes of domesticity, living as couples, families, and housemates. Using formal portrait conventions to aestheticize the images, Opie photographed her subjects in and around their actual homes to create images that are documentary in essence. The series works to represent the lesbian community, which Opie felt had …

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Actual Entities: A Control Method For Unmanned Aerial Vehicles, Erica Absetz Apr 2013

Actual Entities: A Control Method For Unmanned Aerial Vehicles, Erica Absetz

Theses and Dissertations

The focus of this thesis is on Actual Entities, a concept created by the philosopher Alfred North Whitehead, and how the concept can be applied to Unmanned Aerial Vehicles as a behavioral control method. Actual Entities are vector based, atomic units that use a method called prehension to observe their environment and react with various actions. When combining multiple Actual Entities a Colony of Prehending Entities is created; when observing their prehensions an intelligent behavior emerges. By applying the characteristics of Actual Entities to Unmanned Aerial Vehicles, specifically in a situation where they are searching for targets, this emergent, intelligent …

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Choosing The Cut Point For A Restricted Mean In Survival Analysis, A Data Driven Method, Emily H. Sheldon Apr 2013

Choosing The Cut Point For A Restricted Mean In Survival Analysis, A Data Driven Method, Emily H. Sheldon

Theses and Dissertations

Survival Analysis generally uses the median survival time as a common summary statistic. While the median possesses the desirable characteristic of being unbiased, there are times when it is not the best statistic to describe the data at hand. Royston and Parmar (2011) provide an argument that the restricted mean survival time should be the summary statistic used when the proportional hazards assumption is in doubt. Work in Restricted Means dates back to 1949 when J.O. Irwin developed a calculation for the standard error of the restricted mean using Greenwood’s formula. Since then the development of the restricted mean has …

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Camk-Ii: An Integral Protein In Cell Migration, Jamie Josephine Avila Mcleod Apr 2013

Camk-Ii: An Integral Protein In Cell Migration, Jamie Josephine Avila Mcleod

Theses and Dissertations

Coordinated inductive and morphogenetic processes of gastrulation establish the zebrafish body plan. Gastrulation includes massive cell rearrangements to generate the three germ layers and shape the embryonic body. Three modes of cell migration must occur during vertebrate gastrulation and include: epiboly, internalization of the presumptive mesendoderm and convergent extension (C&E). C&E movements narrow the germ layers mediolaterally (convergence) and elongate them anteroposteriorly (extension) to define the embryonic axis. The molecular mechanisms regulating coordinated cell migrations remain poorly understand and studying these has become of great interest to researchers. Understanding cell migration during development is highly relevant to a number of …

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The Mechanotransduction Of Primary Cilia In Tumor Progression Of Lung Adenocarcinoma, Sagar Patel Apr 2013

The Mechanotransduction Of Primary Cilia In Tumor Progression Of Lung Adenocarcinoma, Sagar Patel

Theses and Dissertations

The objective of this study was to investigate primary cilia and their mechanotransduction role in lung adenocarcinoma tumor progression. The main focus investigated the effect of primary cilia on cell cycle progression, survival, adhesion and migration analysis of these cells and the role of sonic hedgehog signaling pathway in mechanotransduction. Human Non-Small Cell Lung Cancer (NSCLC) adenocarcinoma biopsies contain more primary cilia than non-tumor lung sections. To observe the effects of primary cilia presence in lung cancer cells in-vitro, formation of primary cilia is inhibited using small interfering RNA. A549 cells with intact primary cilia observe less cell cycle progression …

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The Inflammasome In Acute Myocarditis, Harsha Kannan Apr 2013

The Inflammasome In Acute Myocarditis, Harsha Kannan

Theses and Dissertations

Acute myocarditis is an acute inflammatory syndrome characterized by myocardial damage and dysfunction often due to a viral infection followed by a variable development over time. There are currently no specific treatments and standard treatments for heart failure are generally applied. The inflammasome is a recently identified macromolecular structure that occupies a central role in the amplification of the inflammatory response and promotion of cell death during acute and chronic infections. We hypothesized the formation of the inflammasome in acute myocarditis. To investigate, samples of patients were collected from the Cardiomyopathy Registry in Trieste, with 12 cases of biopsy-proven myocarditis …

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Understanding Molecular Interactions: Application Of Hint-Based Tools In The Structural Modeling Of Novel Anticancer And Antiviral Targets, And In Protein-Protein Docking, Hardik Parikh Apr 2013

Understanding Molecular Interactions: Application Of Hint-Based Tools In The Structural Modeling Of Novel Anticancer And Antiviral Targets, And In Protein-Protein Docking, Hardik Parikh

Theses and Dissertations

Computationally driven drug design/discovery efforts generally rely on accurate assessment of the forces that guide the molecular recognition process. HINT (Hydropathic INTeraction) is a natural force field, derived from experimentally determined partition coefficients that quantifies all non-bonded interactions in the biological environment, including hydrogen bonding, electrostatic and hydrophobic interactions, and the energy of desolvation. The overall goal of this work is to apply the HINT-based atomic level description of molecular systems to biologically important proteins, to better understand their biochemistry – a key step in exploiting them for therapeutic purposes. This dissertation discusses the results of three diverse projects: i) …

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Defining The Functions Of A Conserved Hydrophobic Domain In The Arf Tumor Suppressor, Aymen Hariz Apr 2013

Defining The Functions Of A Conserved Hydrophobic Domain In The Arf Tumor Suppressor, Aymen Hariz

Theses and Dissertations

The INK4A-ARF locus encodes two tumor suppressors; p16 and p19Arf, both of which restrain cell growth by regulating the functions of Retinoblastoma (Rb) and p53 respectively. Throughout development, p19Arf is kept at minimal levels, but under conditions of oncogenic stress, p19Arf expression is induced and its tumor suppressive activities are mediated through the stabilization of p53 or in a p53-independent manner. Introducing a point mutation (L46D) into the conserved hydrophobic domain (37-51) in p19Arf annulled ARF/CtBP2 interaction and mediated cell survival by rendering cells irresponsive to apoptosis. In vivo analysis on the percentage of lymphoma free survivals in ARFL46D/L46D mice …

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