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Increased Severity Of Murine Infection With Toxioplasma Gondii Following Vitaman E And Selenium Supplementatoin, Susan Mccarthy

Masters Theses & Specialist Projects

At present, toxoplasmosis is one of the most common opportunistic infections in immunocompromised patients. The need for a reliable experimental model is crucial not only for achieving a better understanding of the pathophysiology of this infection but also for developing a better method to evaluate new therapeutic regimens. This study was organized to determine if the antioxidants vitamin E and selenium would provide a beneficial effect in mice chronically infected with Toxoplasma gondii. In the first phase of the study, 35 female Swiss Webster mice were infected with oocysts of the Me49 strain of Toxoplasma gondii while receiving diets supplemented …

Screening For Mutants In The Output Pathway Of The Circadian Clock In Chlamydomonas Reinhardtii, Wei Yuan

Masters Theses & Specialist Projects

The circadian clock is a basic component of biological systems and has been found in many organisms. It is composed by three major components: the input pathway, the oscillator and the output pathway. The purpose of this research is to study the output pathway of the circadian clock in Chlamydomonas reinhardtii strain Carnil by screening mutants, which were generated by insertional mutagenesis via glass bead transformation. The plasmid pSP124S containing the ble marker was used to introduce mutations. The CABII-1 gene has been reported to show a circadian rhythm in expression. The reporter gene ARS2 that was transcriptionally fused to …

Genetic Control Of Eye Development, A Case Study Focused On The Murine Mutation Belly Spot And Tail (Bst), Qing Tang

Theses and Dissertations (ETD)

Development of the eye is controlled by a network of genes, often conserved, that regulate the timing and location of cellular differentiation. One approach to understanding this network of genes and their interaction is to focus on mutations, spontaneous or induced, that predictably disrupt the proper function of such networks, and by examining the effect of such disruption on the function of other genes.

The Belly spot and tail (Bst) semi-dominant mutation, mapped to mouse Chromosome 16, leads to developmental defects of the eye, skeleton, and coat pigmentation. In the eye, the mutant phenotype is characterized by the presence of …

A Ligand Binding Domain Mutation In The Mouse Glucocorticoid Receptor Functionally Links Chromatin Remodeling And Transcription Initiation, Lynn A. Sheldon, Catharine L. Smith, Jack E. Bodwell, Allan U. Munck, Gordon L. Hager

Dartmouth Scholarship

We utilized the mouse mammary tumor virus (MMTV) long terminal repeat (LTR) in vivo to understand how the interaction of the glucocorticoid receptor (GR) with a nucleosome-assembled promoter allows access of factors required for the transition from a repressed promoter to a derepressed, transcriptionally competent promoter. A mutation (C644G) in the ligand binding domain (LBD) of the mouse GR has provided information regarding the steps required in the derepression/activation process and in the functional significance of the two major transcriptional activation domains, AF1 and AF2. The mutant GR activates transcription from a transiently transfected promoter that has a disordered nucleosomal …

Monoclonal Antibody 1a7 And Related Polypeptides, Malaya Chatterjee, Kenneth A. Foon, Sunil K. Chatterjee

Microbiology, Immunology and Molecular Genetics Faculty Patents

The present invention relates to monoclonal antibody 1A7. This is an anti-idiotype produced by immunizing with an antibody specific for ganglioside GD2, and identifying a hybridoma secreting antibody with immunogenic potential in a multi-step screening process. Also disclosed are polynucleotide and polypeptide derivatives based on 1A7, including single chain variable region molecules and fusion proteins, and various pharmaceutical compositions. When administered to an individual, the 1A7 antibody overcomes immune tolerance and induces an immune response against GD2, which comprises a combination of anti-GD2 antibody and GD2-specific T cells. The invention further provides methods for treating a disease associated with altered …

Cartilage Regeneration On A Large Articular Surface Facilitated By Stress Shielding, Charles L. Mcdowell, Jennifer S. Wayne, Robert Tuten, Hunter H. Mcguire Jr.

Virginia Journal of Science

An animal model for the study of articular cartilage regeneration in-vivo facilitated by stress-shielding is introduced. The object of the model is to test the hypothesis that some form of cartilaginous tissue will grow upon a large joint surface in vivo with the joint in normal motion. The model utilizes the known capability of immature cells to differentiate. The source of cells is bleeding subchondral bone. In addition, the model provides a mechanically shielded environment in which cell differentiation and maturation can occur. The study showed that a substantial amount of tissue will grow in the animal model only when …

Differential Transcription Of The Tcpph Operon Confers Biotype-Specific Control Of The Vibrio Cholerae Toxr Virulence Regulon, Yvette M. Murley, Patricia A. Carroll, Karen Skorupski, Ronald K. Taylor, Stephen B. Calderwood

Dartmouth Scholarship

Epidemic strains of Vibrio cholerae O1 are divided into two biotypes, classical and El Tor. In both biotypes, regulation of virulence gene expression depends on a cascade in which ToxR activates expression of ToxT, and ToxT activates expression of cholera toxin and other virulence genes. In the classical biotype, maximal expression of this ToxR regulon in vitro occurs at 30 degrees C at pH 6.5 (ToxR-inducing conditions), whereas in the El Tor biotype, production of these virulence genes only occurs under very limited conditions and not in response to temperature and pH; this difference between biotypes is mediated at the …

Phosphoinositide-Ap-2 Interactions Required For Targeting To Plasma Membrane Clathrin-Coated Pits., I Gaidarov, James H. Keen

Department of Microbiology and Immunology Faculty Papers

The clathrin-associated AP-2 adaptor protein is a major polyphosphoinositide-binding protein in mammalian cells. A high affinity binding site has previously been localized to the NH(2)-terminal region of the AP-2 alpha subunit (Gaidarov et al. 1996. J. Biol. Chem. 271:20922-20929). Here we used deletion and site- directed mutagenesis to determine that alpha residues 21-80 comprise a discrete folding and inositide-binding domain. Further, positively charged residues located within this region are involved in binding, with a lysine triad at positions 55-57 particularly critical. Mutant peptides and protein in which these residues were changed to glutamine retained wild-type structural and functional characteristics by …

Method Of Protecting Against Neuron Loss, Philip W. Landfield

Pharmacology and Nutritional Sciences Faculty Patents

The present invention pertains to a method of protecting against neuron loss in a subject by administering a compound that protects against neuron loss by acting through a vitamin D receptor. Some of these compounds may prevent or retard neuron loss by regulating intraneuronal and/or peripheral calcium and phosphate levels. Other compounds of the invention act through a vitamin D receptor to protect against neuron loss through mechanisms not involving calcium or phosphate regulation. A preferred compound is a biologically active form of vitamin D, a precursor, metabolite, or analog of vitamin D. A preferred form of vitamin D is …

Polynucleotides Related To Monoclonal Antibody 1a7 And Use For The Treatment Of Melanoma And Small Cell Carcinoma, Malaya Chatterjee, Kenneth A. Foon, Sunil K. Chatterjee

Microbiology, Immunology and Molecular Genetics Faculty Patents

The present invention relates to monoclonal antibody 1A7. This is an anti-idiotype produced by immunizing with an antibody specific for ganglioside GD2, and identifying a hybridoma secreting antibody with immunogenic potential in a multi-step screening process. Also disclosed are polynucleotide and polypeptide derivatives based on 1A7, including single chain variable region molecules and fusion proteins, and various pharmaceutical compositions. When administered to an individual, the 1A7 antibody overcomes immune tolerance and induces an immune response against GD2, which comprises a combination of anti-GD2 antibody and GD2-specific T cells. The invention further provides methods for treating a disease associated with altered …

The Effects Of Phosphorus Enrichment On The Dominant Phytoplankton Communities Of Chaney Lake, Kathy Tehrani

Masters Theses & Specialist Projects

Chaney Lake is a temporary karst wetland located in southern Warren County, Kentucky. Because of an impermeable chert layer between the surface and the porous limestone, Chaney Lake fills with water over the winter and spring and then gradually drains over the summer. Three experiments were conducted over the course of the 1998 flooding season to assess the effects of phosphorus addition on the phytoplankton community in Chaney Lake. Ten plastic-sided mesocosms were constructed and placed in the marsh area of the wetland at three different periods: early spring, early summer, and late summer. Phosphorus in the form of K2HPO4 …

The Localization Of Gaba-Like Immunoreactivity In The Optic Lobe Neuropils And Optic Tracts Of The Cockroach Leucophaea Maderae, David Guffey

Masters Theses & Specialist Projects

Gamma aminobutyric acid (GABA) is a prominent neurotransmitter found in both vertebrates and invertebrates. The action of GABA has been accepted to be inhibitory in nature, but recent evidence suggests it is both inhibitory and excitatory, depending upon time of day. The amount of GABA measured in the brain of the cockroach Leucophaea maderae was discovered to fluctuate in a circadian pattern similar to the pattern of electrical output measured from the optic nerve in L. maderae. Considering the circadian oscillator for L. maderae has been localized to the optic lobes of the brain, the discovery of GABA-like immunoreactivity in …

Genetic And Structural Analyses Of Cytoplasmic Filaments Of Wild-Type Treponema Phagedenis And A Flagellar Filament-Deficient Mutant, Jacques Izard, William A. Samsonoff, Mary Beth Kinoshita, Ronald J. Limberger

Department of Food Science and Technology: Faculty Publications

Unique cytoplasmic filaments are found in the treponeme genus of spirochete bacteria. Their function is unknown, but their location underneath the periplasmic flagellar filaments (PFF) suggests a role in motility and/or cell structure. To better understand these unique structures, the gene coding for the cytoplasmic filaments, cfpA, was identified in various treponemal species. Treponema phagedenis cfpA was 2,037 nucleotides long, and the encoded polypeptide showed 78 to 100% amino acid sequence identity with the partial sequence of CfpA from T. denticola, T. vincentii, and T. pallidum subsp. pertenue. Wild-type T. phagedenis and a …

Global Cns Gene Transfer For A Childhood Neurogenetic Enzyme Deficiency: Canavan Disease., Paola Leone, Christopher G Janson, Scott J Mcphee, Matthew J During

Department of Neurosurgery Faculty Papers

The neurogenetic prototypic disease on which we chose to test our gene therapy strategy is Canavan disease (CD). CD is an autosomal recessive leukodystrophy associated with spongiform degeneration of the brain. At present the disease is uniformly fatal in affected probands. CD is characterized by mutations in the aspartoacylase (ASPA) gene, resulting in loss of enzyme activity. In this review, recent evidence is summarized on the etiology and possible treatments for CD. In particular, we discuss two gene delivery systems representing recent advances in both viral and liposome technology: a novel cationic liposome-polymer-DNA (LPD) complex, DCChol/DOPE-protamine, as well as recombinant …

Effects Of Community Structure On The Seagrass Thalassia Testudinum, Craig D. Rose, Clinton J. Dawes

Integrative Biology Faculty and Staff Publications

The influence of community structure on the seagrass Thalassia testudinum was studied in 3 distinct communities: low and high density monocultures, and patches intermixed with Halodule wrightii, in Cockroach Bay, Tampa, Florida. T. testudinum shoot-specific leaf mass and growth were significantly higher in low density monocultures, and both variables were negatively correlated with short-shoot density. Intraspecific, competition-density effects in high-density seagrass beds may be responsible for the relatively lower shoot-specific leaf mass and growth rates, possibly due to the reduction of available light from dense leaf canopies. These observations are supported by significantly higher T. testudinum leaf C:N and …

Protein Adducts Of Iso[4]Levuglandin E2, A Product Of The Isoprostane Pathway, In Oxidized Low Density Lipoprotein, Robert G. Salomon, Wei Sha, Cynthia Brame, Kamaljit Kaur, Ganesamoorthy Subbanagounder, June O'Neil, Henry F. Hoff, L. Jackson Roberts Ii

Pharmacy Faculty Articles and Research

Levuglandin (LG) E₂, a cytotoxic seco prostanoic acid co-generated with prostaglandins by nonenzymatic rearrangements of the cyclooxygenase-derived endoperoxide, prostaglandin H₂, avidly binds to proteins. That LGE₂-protein adducts can also be generated nonenzymatically is demonstrated by their production during free radical-induced oxidation of low density lipoprotein (LDL). Like oxidized LDL, LGE₂-LDL, but not native LDL, undergoes receptor-mediated uptake and impaired processing by macrophage cells. Since radical-induced lipid oxidation produces isomers of prostaglandins, isoprostanes (isoPs), via endoperoxide intermediates, we postulated previously that a similar family of LG isomers, isoLGs, is cogenerated with isoPs. Now …

K-Cl Cotransport: Membrane Immunofluorescence Localization By Confocal Microscopy Of The Kcc1 Protein, Before And After Truncation Of The Cooh-Terminal Domain, In Human Embryonic Kidney (Hek293) Cells, Peter K. Lauf, Kenneth B.E. Gagnon, Jin Zhang, Eric Delpire, Robert E.W. Fyffe, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Clinical Trials In Alzheimer Disease: Debate On The Use Of Placebo Controls, Peter J. Whitehouse

Faculty Scholarship

During the past 10 years, there has been a rapidly growing number of pharmaceutical industry-sponsored drug trials for treatment of Alzheimer disease (AD) and other neurodegenerative diseases. As public awareness and concerns about AD have grown, so has interest in developing drug therapies for retarding symptom progression, delaying onset, and ultimately curing the disease. Ethical debate on the use of placebo control trials in AD research has come of age in the United States with the availability of treatments approved by the Food and Drug Administration. The experts and the public agree that more effective therapies are necessary, and new …

Dichotomy Between Naïve And Memory Cd4+ T Cell Responses To Fas Engagement, J. Desbarats, T. Wade, W. F. Wade, M. K. Newell

Dartmouth Scholarship

Engagement of Fas (APO-1, CD95), a member of the tumor necrosis factor receptor superfamily, can induce apoptotic cell death. However, Fas engagement also can costimulate lymphocyte proliferation. The physiologic regulation of these two outcomes is poorly understood. Here, we have used two systems, the first in vitro and the second in vivo, to demonstrate that naïve and memory CD4+ T cells display dichotomous responses to Fas ligation. Naïve CD4+ T cells (CD44lo, CD45RB+, CD62L+) die as a consequence of Fas ligation in the presence of anti-CD3 antibody, whereas memory T cells (CD44hi, CD45RB−, CD62L−), freshly isolated from the same …

Optimal Replication Activity Of Vesicular Stomatitis Virus Rna Polymerase Requires Phosphorylation Of A Residue(S) At Carboxy-Terminal Domain Ii Of Its Accessory Subunit, Phosphoprotein P, Leroy N. Hwang, Nathan Englund, Tapas Das, Amiya K. Florida, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

The phosphoprotein, P, of vesicular stomatitis virus (VSV) is a key subunit of the viral RNA-dependent RNA polymerase complex. The protein is phosphorylated at multiple sites in two different domains. We recently showed that specific serine and threonine residues within the amino-terminal acidic domain I of P protein must be phosphorylated for in vivo transcription activity, but not for replication activity, of the polymerase complex. To examine the role of phosphorylation of the carboxy-terminal domain II residues of the P protein in transcription and replication, we have used a panel of mutant P proteins in which the phosphate acceptor sites …

Core-Binding Factor Influences The Disease Specificity Of Moloney Murine Leukemia Virus, Amy F. Lewis, Terryl Stacy, William R. Green, Lekidelu Taddesse-Heath, Janet W. Hartley, Nancy A. Speck

Dartmouth Scholarship

The core site in the Moloney murine leukemia virus (Moloney MLV) enhancer was previously shown to be an important determinant of the T-cell disease specificity of the virus. Mutation of the core site resulted in a significant shift in disease specificity of the Moloney virus from T-cell leukemia to erythroleukemia. We and others have since determined that a protein that binds the core site, one of the core-binding factors (CBF) is highly expressed in thymus and is essential for hematopoiesis. Here we test the hypothesis that CBF plays a critical role in mediating pathogenesis of Moloney MLV in vivo. We …

A Vibrio Cholerae Lysr Homolog, Aphb, Cooperates With Apha At The Tcpph Promoter To Activate Expression Of The Toxr Virulence Cascade, Gabriela Kovacikova, Karen Skorupski

Dartmouth Scholarship

We describe here a new member of the LysR family of transcriptional regulators, AphB, which is required for activation of the Vibrio cholerae ToxR virulence cascade. AphB activates the transcription of the tcpPH operon in response to environmental stimuli, and this process requires cooperation with a second protein, AphA. The expression of neither aphA or aphB is strongly regulated by environmental stimuli, raising the possibility that the activities of the proteins themselves may be influenced under various conditions. Strains of the El Tor biotype of V. cholerae typically exhibit lower expression of ToxR-regulated virulence genes in vitro than classical strains …

Three V-Snares And Two T-Snares, Present In A Pentameric Cis-Snare Complex On Isolated Vacuoles, Are Essential For Homotypic Fusion, Christian Ungermann, Gabriele F. Von Mollard, Ole N. Jensen, Nathan Margolis, Tom H. Stevens, William Wickner

Dartmouth Scholarship

Vacuole SNAREs, including the t-SNAREs Vam3p and Vam7p and the v-SNARE Nyv1p, are found in a multisubunit "cis" complex on isolated organelles. We now identify the v-SNAREs Vti1p and Ykt6p by mass spectrometry as additional components of the immunoisolated vacuolar SNARE complex. Immunodepletion of detergent extracts with anti-Vti1p removes all the Ykt6p that is in a complex with Vam3p, immunodepletion with anti-Ykt6p removes all the Vti1p that is complexed with Vam3p, and immunodepletion with anti-Nyv1p removes all the Ykt6p in complex with other SNAREs, demonstrating that they are all together in the same cis multi-SNARE complex. After priming, which disassembles …

Interaction Between Fgf And Bmp Signaling Pathways Regulates Development Of Metanephric Mesenchyme., Andrew T. Dudley, R. E. Godin, E. J. Robertson

Journal Articles: Genetics, Cell Biology & Anatomy

Nephrogenesis in the mouse kidney begins at embryonic day 11 and ends approximately 10 days postpartum. During this period, new nephrons are continually being generated from a stem-cell population-the nephrogenic mesenchyme-in response to signals emanating from the tips of the branching ureter. Relatively little is known about the mechanism by which the nephrogenic mesenchyme cell population is maintained at the tips of the ureter in the presence of signals promoting tubulogenesis. Previous studies have shown that a loss of Bmp7 function leads to kidney defects that are a likely result of progressive loss of nephrogenic mesenchyme by apoptosis. The studies …

Characterizing Erythrocyte Motions In Flowing Blood, Markos Leggas

Theses and Dissertations (ETD)

Characterizing the probabilistic motions of cells is a prerequisite for the development of a general model of transport and surface deposition of white cells and platelets (WBC/P). These phenomena differ greatly when red blood cells (RBC) are present at normal levels, but follow convective diffusion in dilute suspensions. A critical need is to understand and characterize dispersion and diffusion as they apply to red cells in suspension flow. The dispersive motions of
0.5-micrometer beads and fluorescently labeled human RBC flowing in dilute (0.003%) and concentrated (25%) RBC suspensions, respectively, were characterized using fluorescence videomicroscopy methods, and times for individual tracer …

Insertional Inactivation Of Treponema Denticola Tap1 Results In A Nonmotile Mutant With Elongated Flagellar Hooks, Ronald J. Limberger, Linda L. Slivienski, Jacques Izard, William A. Samsonoff

Department of Food Science and Technology: Faculty Publications

The treponemal fla operon is comprised of numerous motility-related genes; however, the initial gene of this operon, tap1, has no known function. A recently developed system to generate specific mutants in Treponema denticola was utilized to determine if Tap1 was essential for motility. T. denticola tap1 and flanking DNA were identified, cloned, and sequenced, and a suicide plasmid that contained tap1 interrupted with an erythromycin resistance cassette (ermF and ermAM) was constructed. Because of potential polar effects from this cassette, a second plasmid that contained tap1 interrupted with a modified erythromycin resistance cassette that lacked the putative ermF transcription …

Interruption Of Multiple Cellular Processes In Ht-29 Epithelial Cells By Pseudomonas Aeruginosa Exoenzyme S, Joan C. Olson, Jennifer E. Fraylick, Eileen M. Mcguffie, Katherine M. Dolan, Timothy L. Yahr, Dara W. Frank, Timothy S. Vincent

Dartmouth Scholarship

Exoenzyme S (ExoS), an ADP-ribosylating enzyme produced by the opportunistic pathogen Pseudomonas aeruginosa, is directly translocated into eukaryotic cells by bacterial contact. Within the cell, ExoS ADP-ribosylates the cell signaling protein Ras and causes inhibition of DNA synthesis and alterations in cytoskeletal structure. To further understand the interrelationship of the different cellular effects of ExoS, functional analyses were performed on HT-29 epithelial cells after exposure to ExoS-producing P. aeruginosa 388 and the non-ExoS-producing strain 388DeltaS. Two different mechanisms of morphological alteration were identified: (i) a more-transient and less-severe cell rounding caused by the non-ExoS-producing strain 388DeltaS and (ii) a more-severe, …

Study Of The Baig Gene In Bile Acid 7Α-Dehydroxylating Bacteria, Michael David

Masters Theses & Specialist Projects

Recently, intestinal bile acid 7α-dehydroxylating bacteria have been implicated in cholesterol gallstone disease. Eubacterium sp. strain V.P.I. 12708, a bile acid 7α-dehydroxylating bacteria, contains multiple bile acid inducible (bai) genes which are located on a large bai operon. Genes of this operon encode the enzymes responsible for bile acid 7α-dehydroxylation. The baiG gene encodes a bile acid transporter in Eubacterium sp. strain V.P.I. 12708. Utilizing the polymerase chain reaction I determined the presence or absence of baiG-like genes in six bile acid 7α-dehydroxylating strains: Clostridium sp. Strain TN-271, Eubacterium sp. strain 1-10, Clostridium bifermentans strain 1-55, Clostridium sordellii strain Y67, …

Signal Transducer And Activator Of Transcription (Stat)5 Activation By Bcr/Abl Is Dependent On Intact Src Homology (Sh)3 And Sh2 Domains Of Bcr/Abl And Is Required For Leukemogenesis., M Nieborowska-Skorska, M A Wasik, A Slupianek, P Salomoni, T Kitamura, B Calabretta, T Skorski

Department of Microbiology and Immunology Faculty Papers

Signal transducer and activator of transcription (STAT)5 is constitutively activated in BCR/ ABL-expressing cells, but the mechanisms and functional consequences of such activation are unknown. We show here that BCR/ABL induces phosphorylation and activation of STAT5 by a mechanism that requires the BCR/ABL Src homology (SH)2 domain and the proline-rich binding site of the SH3 domain. Upon expression in 32Dcl3 growth factor-dependent myeloid precursor cells, STAT5 activation-deficient BCR/ABL SH3+SH2 domain mutants functioned as tyrosine kinase and activated Ras, but failed to protect from apoptosis induced by withdrawal of interleukin 3 and/or serum and did not induce leukemia in severe combined …

Role Of Gamma Interferon In Cellular Immune Response Against Murine Encephalitozoon Cuniculi Infection, Imtiaz A. Khan, Magali Moretto

Dartmouth Scholarship

Microsporidia are obligate intracellular protozoan parasites that cause a wide variety of opportunistic infection in patients with AIDS. Because it is able to grow in vitro, Encephalitozoon cuniculi is currently the best-studied microsporidian. T cells mediate protective immunity against this parasite. Splenocytes obtained from infected mice proliferate in vitro in response to irradiated parasites. A transient state of hyporesponsiveness to parasite antigen and mitogen was observed at day 17 postinfection. This downregulatory response could be partially reversed by addition of nitric oxide (NO) antagonist to the culture. Mice infected withE. cuniculi secrete significant levels of gamma interferon (IFN-γ). Treatment …