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Creation Of Multilinage Adult Stem-Like Cells From Terminally Differentiatied Fibroblasts, John Moore Jul 2011

Creation Of Multilinage Adult Stem-Like Cells From Terminally Differentiatied Fibroblasts, John Moore

Theses and Dissertations

Induced Pluripotent Stem cells (iPScs) are artificially generated cells that demonstrate multilineage differentiation potential. These cells demonstrate similar morphology and high differentiation potential to Embryonic Stem Cells (ESCs). Generation of these cells from a terminally differentiated cell line requires activation of the core pluripotency genes Nanog, Oct4, and Sox2 as well as an oncogenic stimulus such as c-Myc. Here we examine the effect of the Human Pappiloma Virus derived proteins E6 and E7 on the ability of a terminally differentiated fibroblast cell line to a more primitive state and examine its multilineage differentiation capacity. In this paper, we attempt to …

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Development Of A Multiple Vehicle Collaborative Unmanned Aerial System, Lloyd B. Mize Iv Jul 2011

Development Of A Multiple Vehicle Collaborative Unmanned Aerial System, Lloyd B. Mize Iv

Theses and Dissertations

The purpose of this research was to design a multiple UAV system with collaborative operation. This project is built on work that has been done in the field of Unmanned Systems at VCU and is aimed at providing a starting point for research into collaborative control of multiple UAVs. The current GCS software was extended to include multiple vehicles per single controller via a new communication protocol. Many changes were made to the user interface to facilitate controlling multiple vehicles with a single operator. A second processor, called an MCS, was added to each vehicle to allow for greater flexibility …

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Performance Comparison Of Layered Composite Bimodal Fiber Mats With Unimodal Fiber Mats, Sukhada Sanjay Kulkarni Jul 2011

Performance Comparison Of Layered Composite Bimodal Fiber Mats With Unimodal Fiber Mats, Sukhada Sanjay Kulkarni

Theses and Dissertations

The study was conducted to evaluate and compare performance of unimodal and bimodal mats with approximately same mass. 10% and 18% Nylon 4, 6 polymer solution were used for electrospinning the fibers. A negative ion source was used to neutralize the surface charge. The fiber diameters were measured with SEM and were <500 nm thus incorporating the slip effect. Bimodal mats were prepared from different deposition modes. Optimal mode was selected on analyzing the performance factors. The bimodal mats were then compared with unimodal mats. For their performance the fiber mass for these mats was approximately the same. It was observed that the unimodal mats had higher efficiencies and higher pressure drop giving a lower FOM. Bimodal mats showed lower efficiencies and pressure drop compared to unimodal mats. However, the FOM for bimodal mats was approximately 200% higher than unimodal mats

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Functional Characterization Of The Streptococcus Sanguinis Com Regulon, Jill Callahan Jul 2011

Functional Characterization Of The Streptococcus Sanguinis Com Regulon, Jill Callahan

Theses and Dissertations

Streptococcus sanguinis is an important component of the dental plaque biofilm and is believed to play a beneficial role in the oral cavity. S. sanguinis is also a leading cause of infective endocarditis (IE), a potentially lethal infection of the cardiac valves. S. sanguinis possesses genetic competence, the ability to acquire exogenous DNA into its genome. In the well characterized system of S. pneumoniae, genetic competence requires a quorum sensing system encoded by the early comCDE genes, as well as late genes controlled by the alternate sigma factor, ComX. Previous studies in other streptococcal species have suggested functions for the …

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Silk Fibroin-Based Scaffolds For Tissue Engineering Applications, Jennifer Mccool Jul 2011

Silk Fibroin-Based Scaffolds For Tissue Engineering Applications, Jennifer Mccool

Theses and Dissertations

This study focused on the comparison of the electrospun silk scaffolds to the electrospun silk fibroin gel scaffolds. Moreover, this study examined the differences in cross-linking effects of genipin and methanol as well as solvents on the mechanical properties and cell compatibility of the scaffolds. Silk scaffolds were electrospun from an aqueous solution or 1,1,1,3,3-hexafluoro-2-propanol (HFIP) without genipin, immediately after 8 % (wt) genipin was added to the solution, and 18 hours after genipin blended with the solution. Uniaxial tensile testing determined that the silk scaffolds electrospun from water exhibit a higher modulus and peak stress than that of the …

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A Comparative Study Of A Pathogenic Versus A Nonpathogenic Naegleria Species, Melissa Jamerson Jul 2011

A Comparative Study Of A Pathogenic Versus A Nonpathogenic Naegleria Species, Melissa Jamerson

Theses and Dissertations

Naegleria fowleri (N. fowleri) and Naegleria lovaniensis (N. lovaniensis) are closely related amebae found in the environment. N. fowleri causes Primary Amebic Meningoencephalitis (PAM), a fatal disease of the central nervous system, while N. lovaniensis is nonpathogenic. N. fowleri infection occurs when amebae enter the nasal passages, and migrate to the brain. The molecular mechanisms involved in the pathogenesis of PAM are not well-defined. Therefore, the purpose of this study was to define phenotypic characteristics that may be functionally linked to the pathogenicity associated with N. fowleri. Studies revealed that N. fowleri has a faster growth rate and is more …

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Sphingosine-1-Phosphate In Mast Cell-Mediated Allergic Responses, Megan Price Jul 2011

Sphingosine-1-Phosphate In Mast Cell-Mediated Allergic Responses, Megan Price

Theses and Dissertations

Mast cells play a critical role in both acute and chronic inflammation and mature in peripheral tissues from bone marrow-derived progenitors that circulate in the blood as immature precursors. Mast cell progenitors are likely to encounter the serum-borne bioactive sphingolipid metabolite, sphingosine-1-phosphate (S1P), during migration to target tissues. Mast cells developed from human cord blood-derived progenitors cultured with stem cell factor (SCF) alone express intragranular tryptase (MCT), the phenotype predominant in the lung. S1P accelerated the development of cord blood-derived mast cells (CB-MCs) and strikingly increased the numbers of mast cells expressing chymase. These mast cells have functional FcepsilonRI, and …

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Expression Profiling And Functional Validation Of Micrornas Involved In Schizophrenia And Bipolar Disorder, Albert H. Kim Jul 2011

Expression Profiling And Functional Validation Of Micrornas Involved In Schizophrenia And Bipolar Disorder, Albert H. Kim

Theses and Dissertations

MicroRNAs (miRNAs) are a family of small non-coding RNAs that regulate gene expression at both the mRNA and protein levels. MiRNAs have been shown to affect neuronal differentiation, synaptosomal complex localization and synapse plasticity, all functions thought to be disrupted in schizophrenia. We investigated the expression of 667 miRNAs (miRBase v.13) in the prefrontal cortex of individuals with schizophrenia (SZ, N = 35) and bipolar disorder (BP, N =35) using a real-time PCR-based Taqman Low Density Array (TLDA). After extensive QC steps, 441 miRNAs were included in the final analyses. At a FDR of 10%, 22 miRNAs were identified as …

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Detection Of Secreted Proteases And A Membrane Protease In Pathogenic Acanthamoeba Culbertsoni, Shivdeep Deo Jul 2011

Detection Of Secreted Proteases And A Membrane Protease In Pathogenic Acanthamoeba Culbertsoni, Shivdeep Deo

Theses and Dissertations

Acanthamoeba culbertsoni (A. culbertsoni) is an amphizoic amoeba that is the causative agent of Granulomatous Amoebic Encephalitis (GAE), an often fatal central nervous system infection that is seen most frequently in severely immunocompromised patients and is characterized by hemorrhagic and necrotic lesions of the brain as well as varying degrees of granuloma formation. A.culbertsoni isolates have also been identified in a few cases of Amoebic Keratitis, a painful, sight-threatening corneal infection that disproportionately affects contact lens users irrespective of immune status. Common features of both infections include amoebic interaction with host extracellular matrix (ECM) components as requisites for both attachment …

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Structural Basis For Thermal Stability Of Thermophilic Trmd Proteins, Jamar Uzzell Jul 2011

Structural Basis For Thermal Stability Of Thermophilic Trmd Proteins, Jamar Uzzell

Theses and Dissertations

Thermal stability of theG37 tRNA methyltransferase proteins from Thermotoga maritima and Aquifex aeolicus have been compared using Differential Scanning Calorimetry. It was shown that the Thermotoga protein is remarkably stable and is denatured at temperatures in excess of 100 degrees Centigrade. The Aquifex aeolicus protein was less stable, denaturing broadly at temperatures between 55oC and 100oC. In contrast, the mesophilic E. coli protein was completely denatured at 55oC. Enzymatic activity of the proteins was measured at various temperatures. Both the Thermotoga and Aquifex enzymes are active at ambient temperatures, and display a significant decrease in activity when the temperature is …

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Natural Disasters And Older Adults: The Social Construction Of Disaster Planning, Elizabeth Fugate-Whitlock Jul 2011

Natural Disasters And Older Adults: The Social Construction Of Disaster Planning, Elizabeth Fugate-Whitlock

Theses and Dissertations

Examining older adults’ experiences with and response toward hurricanes within the context of the community of residence is key to both understanding their experiences and planning for future hurricanes. Specific to this research, the objective was to understand the current social network of older adults, or who provides care for whom under what circumstances, using the social constructionist perspective. Grounded theory combined with action research was the theoretical orientation guiding the study. Sources of data included the collection of household disaster plans, semi-structured interviews with older adult residents of housing authority neighborhoods, semi-structured interviews with community planners, and observation of …

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Analysis Of The Role Of Outer Surface Protein C (Ospc) In Borrelia Burgdorferi Pathogenesis, Delacy Rhodes Jul 2011

Analysis Of The Role Of Outer Surface Protein C (Ospc) In Borrelia Burgdorferi Pathogenesis, Delacy Rhodes

Theses and Dissertations

Lyme disease is an emerging infection that is caused by the Borrelia burgdorferi sensu lato complex. These bacteria exist in nature through an enzootic life cycle involving Ixodes ticks and various reservoir hosts. One way that this bacterium adapts to the different hosts in the enzootic cycle is through the expression of outer surface protein C (OspC). OspC is a surface exposed lipoprotein encoded on circular plasmid 26 that forms homodimers on the bacterial surface and has distinct conserved and variable portions of sequence. When ospC is deleted, the spirochetes are unable to cause mammalian infection although the mechanism of …

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Joy In Nature, Rebecca Morgan Jul 2011

Joy In Nature, Rebecca Morgan

Theses and Dissertations

Artist Statement I am fascinated with colors in nature and how it affects our moods. The colors of a sunset and moonlit sky; the feeling of a brewing storm; the laziness of a cold, gray day; the roar of an ocean; and the feel of sand on your feet are elements that I want to capture in my drawings and paintings. In addition to the natural environment, animals are an integral part of nature that I incorporate in my work. Pets are the unspoken blessings that bring joy and laughter to my life. Pets, especially dogs, are proven to relieve …

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Modeling Particle Filtration And Caking In Fibrous Filter Media, Seyed Alireza Hosseini Jul 2011

Modeling Particle Filtration And Caking In Fibrous Filter Media, Seyed Alireza Hosseini

Theses and Dissertations

This study is aimed at developing modeling methodologies for simulating the flow of air and aerosol particles through fibrous filter media made up of micro- or nano-fibers. The study also deals with modeling particle deposition (due to Brownian diffusion, interception, and inertial impaction) and particle cake formation, on or inside fibrous filters. By computing the air flow field and the trajectory of airborne particles in 3-D virtual geometries that resemble the internal microstructure of fibrous filter media, pressure drop and collection efficiency of micro- or nano-fiber filters are simulated and compared with the available experimental studies. It was demonstrated that …

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Development And Evaluation Of A Multiplex Suspension Array Protocol For The Detection Of Enteric Pathogens From Clinical Specimens, Carol Walters Jul 2011

Development And Evaluation Of A Multiplex Suspension Array Protocol For The Detection Of Enteric Pathogens From Clinical Specimens, Carol Walters

Theses and Dissertations

Foodborne illnesses are a significant public health challenge in the United States, with an estimated 9.4 million illnesses annually attributed to the consumption of contaminated food, of which 59% are estimated to be caused by viruses, 39% by bacteria and 2% by parasites. Timely detection and identification of the pathogens causing foodborne outbreaks is vital for the implementation of outbreak control strategies, allowing public health officials to prevent additional illnesses and maintain confidence in the food supply. Public health laboratories employ a variety of traditional and molecular testing techniques to identify foodborne outbreak etiologic agents. One technology is the Luminex …

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Analysis And Fingerprinting Of Glycosaminoglycans, Joseph King Jul 2011

Analysis And Fingerprinting Of Glycosaminoglycans, Joseph King

Theses and Dissertations

Heparin is a complex mixture of sulfated polysaccharides derived from animals and one of the oldest drugs in use. While an efficacious anticoagulant, heparin is beset by side effects and pharmacokinetic difficulties. Low molecular weight heparins (LMWH) are made by depolymerizing unfractionated heparin (UFH) and present improvements in these areas. However, they still retain a phenomenally high level of complexity due to their polydispersity and the introduction of non-native structural features. This makes the structural characterization LMWHs a daunting task. This work details the development of a novel capillary electrophoretic (CE) method for fingerprinting LMWHs. Since their complexity normally results …

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Role Of Tyk2 In The Development Of Beige Cells, Samantha Umali Jul 2011

Role Of Tyk2 In The Development Of Beige Cells, Samantha Umali

Theses and Dissertations

Obesity results from an excess of adipose tissue and is a major risk factor for type 2 diabetes, cardiovascular disease, and cancer. Adipose tissue exists in two main forms: white adipose tissue (WAT), which stores energy as triglycerides, and brown adipose tissue (BAT), which dissipates stored energy as heat. White adipose tissue is composed of several subcutaneous and visceral depots, each possessing distinct molecular and functional characteristics. Brown-like adipocytes can emerge in WAT depots in response to cold or beta-adrenergic stimulation. These cells have been called “beige” or “brite” (brown-in-white) cells. The reduction of obesity in mice treated with beta-adrenergic …

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Sythesis And Biological Screening Of A Series Of Novel Chemokine Receptor Ccr5 Antagonists, Soundarya Vaithianathan Jul 2011

Sythesis And Biological Screening Of A Series Of Novel Chemokine Receptor Ccr5 Antagonists, Soundarya Vaithianathan

Theses and Dissertations

The chemokine receptor CCR5 has been implicated in the pathogenesis of cancers and AIDS. A series of novel piperidine derivatives were designed, synthesized, and evaluated as CCR5 antagonists. The ability of the new ligands to inhibit the increment of intracellular calcium level stimulated by endogenous ligand CCL5 was measured in the calcium mobilization assay as an indication of its CCR5 receptor antagonism. The anti-proliferation assay was performed to measure the ability of these new compounds to inhibit the proliferation of prostate cancer cell lines, PC-3 and M12. A new lead compound has been identified which showed micromolar level of inhibition …

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Characterization Of Lysophosphatidic Acid Subspecies Using A Novel Hplc Esi-Ms/Ms Method, Eric Mayton Jul 2011

Characterization Of Lysophosphatidic Acid Subspecies Using A Novel Hplc Esi-Ms/Ms Method, Eric Mayton

Theses and Dissertations

Lysophosphatidic acid (LPA) is a bioactive lipid with a plethora of biological functions, including roles in cell survival, proliferation, and migration. Although high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC ESI-MS/MS) technology has been used to measure the levels of LPA in human blood, serum and plasma, current methods cannot readily detect the minute levels of LPA from cell culture. In this study, a novel HPLC ESI-MS/MS method with enhanced sensitivity was developed which allows accurate measurements of LPA levels with a limit of quantitation at approximately 10 femtomoles. The method was validated by quantitation of LPA levels in …

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Assessing The Role Of Polyethylene Glycol (Peg) In Improving Functional Recovery Following Spinal Cord Injury, Dustin Dalton Jul 2011

Assessing The Role Of Polyethylene Glycol (Peg) In Improving Functional Recovery Following Spinal Cord Injury, Dustin Dalton

Theses and Dissertations

Injury to the spinal cord results in the disruption of signal transmission between the brain and distal targets. It often presents with the loss of motor function and sensory perception below the level of injury. There are many obstacles following injury that must be overcome in order to encourage axon regeneration and improve functional recovery. A combinatorial approach is necessary to combat physical and chemical barriers to recovery. The fluid filled cyst that forms in the majority of spinal cord injuries presents a physical barrier that we treat with our electrospun bridges. We implanted our bridges into female Long Evans …

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Growth Of Age-0 Atlantic Menhaden (Brevoortia Tyrannus) In Two Tidal Freshwater Tributaries Of Chesapeake Bay, Peter M. Sturke Jul 2011

Growth Of Age-0 Atlantic Menhaden (Brevoortia Tyrannus) In Two Tidal Freshwater Tributaries Of Chesapeake Bay, Peter M. Sturke

Theses and Dissertations

Few studies have described growth rates of age-0 Atlantic menhaden (Brevoortia tyrannus). Growth rates from tidal freshwater habitats of the Mattaponi and James Rivers, Virginia in 2009 were described and compared using otolith microstructural analyses. Larval tidal freshwater growth rates were significantly faster in the culturally eutrophic James River when compared to those collected from the Mattaponi River (p-value < 0.001). Elevated primary production within tidal freshwater habitats promotes favorable conditions for larval Atlantic menhaden growth. No differences between river habitats for juvenile growth rates were evident. Comparisons of age-0 growth rates to higher salinity habitats indicate that tidal freshwater habitats should be considered essential habitat for age-0 Atlantic menhaden.

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Commonwealth Times 2011-07-01 Jul 2011

Commonwealth Times 2011-07-01

Commonwealth Times, 1969-

No abstract provided.

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The Relationship Between Physicians‘ Ownership Of Physical Therapy Services And Referral Patterns To Hospital-Based Outpatient Rehabilitation Centers, Joy Bruce Jun 2011

The Relationship Between Physicians‘ Ownership Of Physical Therapy Services And Referral Patterns To Hospital-Based Outpatient Rehabilitation Centers, Joy Bruce

Theses and Dissertations

Background and Purpose A debate over the practice of physician self-referral has been ongoing in health care since the 1980s. At issue is the practice of physicians who refer patients to facilities in which they share a financial interest, a phenomenon known as referral for profit. Physician investment or ownership interest in ancillary (e.g., physical therapy) services has been shown to have an impact on utilization rates, costs, access to care, and quality of care. What has not been identified in previous research is the influence of physicians‘ selective referral on competing clinics, particularly the hospital-based outpatient centers that share …

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Optimization Of A Tri-Layered Vascular Graft: The Influence Of Cellular And Mechanical Properties, Michael Mcclure Jun 2011

Optimization Of A Tri-Layered Vascular Graft: The Influence Of Cellular And Mechanical Properties, Michael Mcclure

Theses and Dissertations

Electrospinning is a polymer processing technique which allows for the production of nano to micro size fibers and scaffolds which can be composed of numerous synthetic biodegradable materials and natural biopolymers. Natively, elastin and collagen are the main components of vascular tissue. Arranged in a tri-layered structure, they create a specific mechanical environment that can withstand the rigors of circulation. The goal of this study was to develop a mechanically ‘biomimicking’ vascular graft composed of three distinct layers through the process of electrospinning. We hypothesize that the use of bioactive agents such as elastin, collagen, and silk to supplement poly(caprolactone) …

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Between Scenic Designer And Director: The Collaborative Process Of Four Productions, Elizabeth R. Muller Jun 2011

Between Scenic Designer And Director: The Collaborative Process Of Four Productions, Elizabeth R. Muller

Theses and Dissertations

This thesis presents the unique designs for four productions: Ain’t Misbehavin’, Is He Dead?, Dead Man’s Cell Phone, and Legacy of Light. Presented here are the research images, conversations, situations and their resulting designs represented in my renderings and photographs of the fully realized production. Throughout, I will state my objectives in bettering the quality of interaction with each director and my reflections on the ongoing process of creating a trusting and balanced collaborative process, one that expertly serves the production.

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Cis 3,4', 5-Trimethoxy-3'-Aminostilbene (Stilbene 5c) Induces Apoptosis And Protective Autophagy In B16f10 Melanoma Cells, Betelehem Asnake Jun 2011

Cis 3,4', 5-Trimethoxy-3'-Aminostilbene (Stilbene 5c) Induces Apoptosis And Protective Autophagy In B16f10 Melanoma Cells, Betelehem Asnake

Theses and Dissertations

The weak selectivity of chemotherapeutic drugs against tumors has sustained efforts to develop better chemotherapeutic agents that are more potent and selective at destroying tumor cell populations versus normal tissues. This project focuses on evaluating the cell killing effects of the microtubule inhibitor, stilbene 5c, against melanoma cancer. We utilized an in vitro murine melanoma model to study the effects of stilbene 5c on tumor proliferation and survival, as well as growth arrest and cell death. Our findings indicate that stilbene 5c promotes dose dependent cell death in melanomas with the induction of apoptosis and autophagy. The role of autophagy …

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Cmv Vaccine Development Based On Epithelial Entry Mediators Ul128, Ul130, Ul131, Frances Saccoccio Jun 2011

Cmv Vaccine Development Based On Epithelial Entry Mediators Ul128, Ul130, Ul131, Frances Saccoccio

Theses and Dissertations

Congenital cytomegalovirus infection is the leading cause of sensorineural hearing loss in the U.S. CMV vaccines developed to date do not protect the majority of women of childbearing age from primary CMV infection. Insufficient vaccine-induced epithelial entry neutralizing activity may be the reason for poor performance of these vaccines. CMV entry into endothelial and epithelial but not fibroblast cells requires the virion envelope complex gH/gL/UL128-131. Since current vaccines do not target this complex, epithelial entry mediators UL128-131 are attractive subunit CMV vaccine candidates, since they should target mucosal immunity. The mucosal immune response, specifically salivary epithelial entry neutralizing activity, has …

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Examination Of Nak-Associated Protein-1 (Nap1) Homo And Hetero-Interactions In The Interferon Pathway”, Richard Call May 2011

Examination Of Nak-Associated Protein-1 (Nap1) Homo And Hetero-Interactions In The Interferon Pathway”, Richard Call

Theses and Dissertations

Double stranded RNA (dsRNA), the genomic material of some viruses and a replication intermediate in others, is recognized by multiple signaling receptors that initiate the anti-viral response1. Viruses have developed mechanisms to circumvent the anti-viral response by targeting components of the signaling pathway. An example of one such pathway is the TLR3 signaling pathway, which contains a kinase complex that activates interferon regulatory factor 3 (IRF3), leading to production of type I interferons. The kinase complex consists of a scaffold protein, NAK-associated protein 1 (NAP1), and two kinases, TANK-binding kinase 1 (TBK-1) and IκB kinase epsilon (IKKε). A fourty residue …

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Enhancing Family Functioning To Buffer Risk During Middle School Transition: Development Of The Multiple Family Group Weekend Retreat., Robert Broce May 2011

Enhancing Family Functioning To Buffer Risk During Middle School Transition: Development Of The Multiple Family Group Weekend Retreat., Robert Broce

Theses and Dissertations

Children experience changes in multiple levels of their social ecologies when they transition into middle school (Eccles, 1999; Jozefowicz-Simbeni, 2008). These biological, psychological, social, and environmental changes create increased risk for dropout and other factors related to academic adjustment (Cataldi, Laird & KewalRamani, 2009). For low- income minority children these risks can be magnified by environmental and social factors (Ge et al., 2002). Healthy family functioning, including balanced levels of cohesion and flexibility, has been shown to buffer these risks (Burchinal, Roberts, Zeisel & Rowley, 2008; Olson, 2010; Wampler, Munsch, & Adams, 2002) and was targeted by a Multiple Family …

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A Sequence Of Gaps, Oscar Santillan May 2011

A Sequence Of Gaps, Oscar Santillan

Theses and Dissertations

This thesis unfolds some theories and reflections on specific works I developed during my MFA. It is a map of the past and present of my art practice, and speculates about its future.

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