Molecular Genetics Commons^™

Development Of A Model For Infective Endocarditis Via Intravenous Injection And Tooth Infection Of Rats Using Pathogenic Bacteria, Shahrokh Shabahang

Loma Linda University Electronic Theses, Dissertations & Projects

Historically, focal areas of infection have been linked to a number of systemic ailments. During the early part of the 20th century, patients who were suffering from inexplicable diseases and who were suspected of having infected teeth were referred to the dentist for multiple extraction of their dentition. The discovery of antibiotics provided a false sense of security that the war against microorganisms is no longer a concern for mankind. However, more recently, it has become common belief that increasing numbers of systemic diseases are linked to chronic infections. Recovery of bacteria from representative tissues has led investigators to believe …

Identification Of Chromosomes In Plants Using Standard Staining Techniques, L. Michael Hill Ph.D.

Biology Faculty Scholarship

No abstract provided.

A Novel Strategy Utilizing Co-Expression Of Murine Il-12 And Antisense Tgf-Pl Against H238 Tumor Formation, Craig A. Seheult

Loma Linda University Electronic Theses, Dissertations & Projects

Cytokines have a profound effect on immune modulation, thus playing a significant role in cancer gene therapy. A variety of human carcinomas secrete transforming growth factor-beta (TGF-β), a cytokine with potent immunosuppressive properties. Suppressing TGF-β could be a key to successfully combating malignancies, such as gliomas, mammary, and colon cancers, that over-express TGF-β. Conversely, interleukin-12 (IL-12) is a potent immunostimulatory cytokine capable of regulating T and NK cell-mediated cytotoxic responses (Trinchieri, 1994) during an anti-tumor response. Activation of the immune system with such immunostimulatory cytokines renders it inert to the suppressive effects of TGF-β. To better understand these processes our …

Effects Of Liposome-Encapsulated Tnf-Alpha And Radiation Against Colon Cancer, Dong Won Kim

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies have shown that tumor necrosis factor-α (TNF-α) can augment the antitumor effects of radiation, inhibiting tumor progression to a greater extent than either modality alone. However, nonspecific toxicities associated with TNF-α have limited its use as an adjuvant. This limitation is potentially resolved with the encapsulation of TNF-α in sterically stabilized, PEGylated liposomes (STEALTH®). Thus, the overall hypothesis of the research was that the combination of radiation with STEALTH® liposome encapsulated TNF-α (SL-TNF-α) will have greater efficacy and fewer dose-limiting side effects in the LS174T human colorectal tumor xenograft model compared to the combination of free TNF-α and …

The Toxoplasma Gondii Protein Rop2 Mediates Host Organelle Association With The Parasitophorous Vacuole Membrane, Anthony P. Sinai, Keith A. Joiner

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Toxoplasma gondii replicates within a specialized vacuole surrounded by the parasitophorous vacuole membrane (PVM). The PVM forms intimate interactions with host mitochondria and endoplasmic reticulum (ER) in a process termed PVM–organelle association. In this study we identify a likely mediator of this process, the parasite protein ROP2. ROP2, which is localized to the PVM, is secreted from anterior organelles termed rhoptries during parasite invasion into host cells. The NH₂-terminal domain of ROP2 (ROP2hc) within the PVM is exposed to the host cell cytosol, and has characteristics of a mitochondrial targeting signal. In in vitro assays, ROP2hc is …

A Cytochrome-B Perspective On Passerina Bunting Relationships, John Klicka, Adam J. Fry, Robert M. Zink, Christopher W. Thompson

Ornithology Program (HRC)

We sequenced the complete mitochondrial cytochrome-b gene (1,143 nucleotides) for representatives of each species in the cardinalid genera Passerina (6 species), Guiraca (1 species), and Cyanocompsa (3 species), and used a variety of phylogenetic methods to address relationships within and among genera. We determined that Passerina, as presently recognized, is paraphyletic. Lazuli Bunting (P. amoena) is sister to the much larger Blue Grosbeak (Guiraca caerulea). Indigo Bunting (P. cyanea) and Lazuli Bunting are not sister taxa as generally thought. In all weighted parsimony trees and for the gamma-corrected HKY tree, Indigo Bunting is …

The Wings Of Bombyx Mori Develop From Larval Discs Exhibiting An Early Differentiated State: A Preliminary Report, Madhuri Kango-Singh, Amit Singh, K. P. Gopinathan

Biology Faculty Publications

Lepidopteran insects present a complex organization of appendages which develop by various mechanisms. In the mulberry silkworm, Bombyx mori, a pair of meso- and meta-thoracic discs located on either side in the larvae gives rise to the corresponding fore- and hind-wings of the adult. These discs do not experience massive cell rearrangements during metamorphosis and display the adult wing vein pattern. We have analysed wing development in B. mori by two approaches, viz., expression of patterning genes in larval wing discs, and regulatory capacities of larval discs following explantation or perturbation. Expression of Nubbin is seen all over the presumptive …

Salivary Acinar Cells From Aquaporin 5-Deficient Mice Have Decreased Membrane Water Permeability And Altered Cell Volume Regulation, Carissa M. Krane, James E. Melvin, Ha-Van Nguyen, Linda Richardson, Jennifer E. Towne, Thomas Doetschman, Anil G. Menon

Biology Faculty Publications

Aquaporins (AQPs) are channel proteins that regulate the movement of water through the plasma membrane of secretory and absorptive cells in response to osmotic gradients. In the salivary gland, AQP5 is the major aquaporin expressed on the apical membrane of acinar cells. Previous studies have shown that the volume of saliva secreted by AQP5-deficient mice is decreased, indicating a role for AQP5 in saliva secretion; however, the mechanism by which AQP5 regulates water transport in salivary acinar cells remains to be determined. Here we show that the decreased salivary flow rate and increased tonicity of the saliva secreted byAqp5 …

Identification Of The Polar Flagellum Genes In Azospirillum Brasilense, Enid Thanna Mckinley

Loma Linda University Electronic Theses, Dissertations & Projects

Azospirillum brasilenser, a nitrogen fixing rhizobacterium, can colonize plant roots and increase the yield of economically important cereals, such as rice and grasses. This organism has a mixed pattern of flagellation: a single polar flagellum for motility in liquid medium and lateral flagella which might be involved in motility across the root surface and or attachment to the root hairs of plants. Flagella dictate A. brasilense chemotactic ability and motility, which plays an important role in colonization of plant roots. However, nothing is known about the genes that code for the polar flagellum. To study the polar flagellum, different mutants …

Il-2 And Antisense Tgf-B1 Gene Therapy Of The H238 Tumor And Analysis Of Tgf-B Receptors, Azim Moiz Mohamedali

Loma Linda University Electronic Theses, Dissertations & Projects

Transforming growth factor-beta (TGF-p) belongs to a family of immunosuppressive cytokines, capable of regulating macrophages, T, B and NK cells. We have detected the TGF-p transcript being synthesized by H238 cells. This is herpes simplex-Type2 transformed murine fibrosarcoma cell line. The amount of TGF-p formed/106 cells was >2000pg/ml. Previous attempts to control H238 tumorigenicity had sub-optimal efficacies. In addition, studies had shown that the FI238 cell line was not responsive to TGF-p. This project was an attempt to develop an improved modality to reduce H238 tumorigenicity and investigate potential abnormalities in expression of TGF-p receptors in the H238 cell line. …

Studies On The Formation Of Dna-Cationic Lipid Composite Films And Dna Hybridization In The Composites, Murali Sastry, Vidya Ramakrishnan, Mrunalini Pattarkine, Krishna N. Ganesh

Faculty Works

The formation of composite films of double-stranded DNA and cationic lipid molecules (octadecylamine, ODA) and the hybridization of complementary single-stranded DNA molecules in such composite films are demonstrated. The immobilization of DNA is accomplished by simple immersion of a thermally evaporated ODA film in the DNA solution at close to physiological pH. The entrapment of the DNA molecules in the cationic lipid film is dominated by attractive electrostatic interaction between the negatively charged phosphate backbone of the DNA molecules and the protonated amine molecules in the thermally evaporated film and has been quantified using quartz crystal microgravimetry (QCM). Fluorescence studies …

Cationic Surfactant Mediated Hybridization And Hydrophobization Of Dna Molecules At The Liquid/Liquid Interface And Their Phase Transfer, Murali Sastry, Ashavani Kumar, Mrunalini Pattarkine, Vidya Ramakrishnan, Krishna N. Ganesh

Faculty Works

Hybridization of complementary oligonucleotides mediated by a cationic surfactant at the water/hexane interface leads to hydrophobic, double-helical DNA which may be readily phase transferred to the organic phase and cast into thin films on solid substrates.

Structural And Functional Characterization Of The Activator Of G-Protein Signaling 3 (Ags3), Michael Labranche Bernard

MUSC Theses and Dissertations

AGS3 (Activator of G-protein Signaling 3) was isolated in yeast-based functional screen for receptor-independent activators of heterotrimeric G-proteins. To examine the role of AGS3 in mammalian signal processing, we defined the AGS3 sub domains involved in G-protein interaction, its selectivity for G-proteins and its influence on the activation state of G-protein. AGS3 co-immunoprecipitated with Gia3 from tissue lysates in a nucleotide dependent manner (GDP»GTPγS). The regions of AGS3 that bound Giα were localized to 4 thirty amino acid repeats (GPR - G-protein regulatory motif) in the carboxyl terminus (P463-S650), each of which were capable of binding Giα. AGS3-GPR domains selectively …

Aquaporin 5-Deficient Mouse Lungs Are Hyperresponsive To Cholinergic Stimulation, Carissa M. Krane, Christopher N. Fortner, Arthur R. Hand, Dennis W. Mcgraw, John N. Lorenz, Susan E. Wert, Jennifer E. Towne, Richard J. Paul, Jeffrey A. Whitsett, Anil G. Menon

Biology Faculty Publications

Although aquaporin 5 (AQP5) is the major water channel expressed in alveolar type I cells in the lung, its actual role in the lung is a matter of considerable speculation. By using immunohistochemical staining, we show that AQP5 expression in mouse lung is not restricted to type I cells, but is also detected in alveolar type II cells, and in tracheal and bronchial epithelium. Aqp5 knockout (Aqp5−/−) mice were used to analyze AQP5 function in pulmonary physiology. Compared with Aqp5+/+ mice, Aqp5−/− mice show a significantly increased concentration-dependent bronchoconstriction to intravenously administered Ach, as shown by …

Hawaiian Freshwater Polychaeta: A Potentially Substantial Trophic Component Of Stream Depositional Habitats, M. Eric Benbow, Albert J. Burky, Carl M. Way

Biology Faculty Publications

In this paper we report the widespread occurrence of large annelids (Polychaeta: Nereididae) in Hawaiian stream depositional habitats, drawing attention to the lack of knowledge of Hawaiian stream energetics. Specimens of Namalycastis sp. were collected from five Hawaiian Islands from May–July 1995 and from the island of Maui from July–December 1999 and April–July 2000. Most specimens collected were N. hawaiiensis, while two specimens of N. abiuma were collected from a single site on the island of Molokai. Specimens were collected from elevations ranging from 3–240 m; several collections were from sites above at least one major (> 15 m …

An Assessment Of Prothrombotic Tendency In Humans Using Functional And Genomic Determinants In The South Eastern Irish Population, Carmel Cullen

Theses

Venous thrombosis occurs in about 1 per 1,000 individuals per year. It is a serious disorder and accounts for a significant number of hospital admissions and deaths annually. Thrombophilia describes the familial or acquired disorders of the haemostatic mechanism that predispose to thrombosis. Inherited thrombophilia can be defined as a genetically determined tendency to venous thromboembolism Mutations in genes that code for proteins involved directly (or indirectly) In blood coagulation have been associated with prothrombotic status. Laboratory investigations for thrombophilia include screening for deficiencies of antithrombin, protein C or protein S and testing for activated protein C resistance. Together these …

Vaccinia Virus-Mediated Glioma Gene Therapy Using P53, Il-2 And Il-12, Bing Chen

Loma Linda University Electronic Theses, Dissertations & Projects

Malignant brain tumors are generally lethal soon after their diagnosis, and the five-year survival rate for the patient is low in spite of neurosurgery, radiation therapy, and/or chemotherapy. Gene therapy has the potential to improve patient survival and quality of life by delivering specific combinations of therapeutic genes directly to the tumor for localized treatment.

We have based our cancer gene therapy for glioma on a highly attenuated variant of the Lister strain of vaccinia virus (VV) which has been proven to be a safe and effective vaccine vector. Other advantages include a wide host range, a strong promoter system, …

Hybridization Of Dna By Sequential Immobilization Of Oligonucleotides At The Air-Water Interface, Murali Sastry, Vidya Ramakrishnan, Mrunalini Pattarkine, Anand Gole, K. N. Ganesh

Faculty Works

The hybridization of DNA by sequential electrostatic and hydrogen-bonding immobilization of single-stranded complementary oligonucleotides at the air-water interface with cationic Langmuir monolayers is demonstrated. The complexation of the single-stranded DNA molecules with octadecylamine (ODA) Langmuir monolayers was followed in time by monitoring the pressure-area isotherms. A large (and slow) expansion of the ODA monolayer was observed during each stage of complexation in the following sequence: primary single-stranded DNA followed by complementary single-stranded DNA followed by the intercalator, ethidium bromide. Langmuir-Blodgett (LB) films of the ODA-DNA complex were formed on different substrates and characterized using quartz-crystal microgravimetry (QCM), Fourier transform infrared …

Accessory Cell Defect In Unresponsiveness Of Neonates And Aged To Polysaccharide Vaccines., Subbarao Bondada, H Wu, D A Robertson, R L Chelvarajan

Microbiology, Immunology, and Molecular Genetics Faculty Publications

T independent antigens elicit antibody responses in the absence of carrier specific T helper cells but require signals from accessory cells (macrophages and dendritic cells) or specific cytokines. They are further subdivided into TI-1 and TI-2 categories based on the ability of TI-1 but not TI-2 antigens to elicit immune responses from neonates. Most bacterial polysaccharides including the pneumococcal polysaccharide vaccines belong to the TI-2 class. It is hypothesized that defects in accessory cell function play a critical role in the failure of neonates to respond to such TI-2 antigens. Immune responses to these TI-2 stimuli are also reduced in …

Connexin-32 Contributes To Radiation Resistance In Thyroid Follicles, Da-Thao Dinh Tran

Loma Linda University Electronic Theses, Dissertations & Projects

The objective of this study was to examine the role of gap junctions in the radiation resistance of thyroid follicles. The question of whether gap junctional intercellular communication plays an important role in the “contact effect”, wherein cells in direct apposition are more resistant to the damaging effects of radiation, has been debated for years. We used the Fischer rat thyroid cell line (FRTL-5) to carry out our experiments. This thesis is divided into two parts: 1) characterization of gap junctional properties in FRTL-5 cells and, 2) exposure of these cells to radiation.

We found that, unlike primary thyroid cells, …

Interactions Of Igf-Ii And Cathepsin D In Mcf-7 Breast Cancer Cells, Jesika S. Faridi

Loma Linda University Electronic Theses, Dissertations & Projects

A primary role of the IGF-II/M6P receptor is to target lysosomal enzymes from the golgi to the lysosomes. This receptor has distinct binding sites for IGF-II and M6P, however, reciprocal interactions between these ligands have been observed (Kiess et al. 1989, 1990). Since IGF-II modulates the routing of cathepsin D in MCF-7 cells by blocking the intracellular binding of cathepsin D to the IGF-II/M6P receptor (De León et al. 1996), we hypothesized that expressing a mutant form of IGF-II that does not bind the IGF-II/M6P receptor will not interfere with lysosomal enzyme trafficking.

In our present study, we report the …

The Occurrence Of The Freshwater Clams, Musculium Partumeium (Say) And Pisidium Casertanum (Poli) (Bivalvia: Sphaeriidae), In The Hawaiian Islands, Albert J. Burky, Carl M. Way, Skippy Hau, M. Eric Benbow

Biology Faculty Publications

Sphaeriid clams were collected from an ancient, continuously cultivated taro pond complex at Ke‘anae Peninsula, Maui. Both species are known for adaptations for temporary pond habitats and could have been initially introduced by the earliest Hawaiian settlers transported with moist taro root stock from other areas of Oceania.

Expression And Requirement Of Epithelial Fatty Acid- Binding Protein In Neuronal Axon Growth, Gregory William Allen

Loma Linda University Electronic Theses, Dissertations & Projects

Epithelial fatty acid-binding protein (E-FABP) is expressed in the dorsal root ganglia following sciatic nerve injury and in migrating and differentiating neurons during neuronal development. It was hypothesized that E-FABP expression is required for the robust outgrowth of axons from developing and regenerating neurons. To test this hypothesis, E-FABP expression in both PC12 cells and primary retinal neurons was examined. In PC12 cells, NGF induces E-FABP mRNA and protein during the period of neurite outgrowth, and E-FABP localizes to the perinuclear cytoplasm, nucleus, and growth cone. Furthermore, E-FABP-deficient cell lines exposed to NGF were less differentiated and had shorter neurites …

Identification And Characterization Of Aer, An Energy Sensor In Escherichia Coli, Anuradha Rebbapragada

Loma Linda University Electronic Theses, Dissertations & Projects

This study investigated the mechanism of signal transduction by Aer, the aerotaxis transducer in E.coli. A computerized search of GenBank revealed an open reading frame at 69.1 min on the E.co//chromosome that had a C-terminal fragment with 96.7% identity to the highly conserved domain of Tsr. The open reading frame was renamed aer for aerotaxis and energy responses. When the aer gene was inactivated, approximately 50% of aerotaxis responses were eliminated. When both aer and fsr were inactivated, aerotaxis, redox taxis and glycerol taxis were completely abolished. Expressing Aer in aer fsr cells restored aerotaxis responses and the duration …

Function And Properties Of Groe Chaperonins In Bacterial And Mammalian Cells, Gregory M. Nelson

Loma Linda University Electronic Theses, Dissertations & Projects

Molecular chaperones play an integral role in the folding of most polypeptides in vivo, and protect proteins against aggregation when a cell is under stress. The GroESL proteins of Escherichia coli are the best characterized of the ringed chaperones, or chaperonins. Chaperonins of the eukaryotic cytoplasm interact with a limited number of polypeptides, whereas GroEL is promiscuous as it binds and mediates the folding of many polypeptides. This feature makes GroEL an attractive protein for investigating various aspects of protein folding in eukaryotic cells because its substrate interaction is diverse. In this work we have expressed the groES and …

Novel Function Of Phosphoinositide 3-Kinase In T Cell Ca2+ Signaling. A Phosphatidylinositol 3,4,5-Trisphosphate-Mediated Ca2+ Entry Mechanism., A L Hsu, T T Ching, G Sen, D S Wang, Subbarao Bondada, K S Authi, C S Chen

Microbiology, Immunology, and Molecular Genetics Faculty Publications

This study presents evidence that phosphoinositide (PI) 3-kinase is involved in T cell Ca(2+) signaling via a phosphatidylinositol 3,4, 5-trisphosphate PI(3,4,5)P(3)-sensitive Ca(2+) entry pathway. First, exogenous PI(3,4,5)P(3) at concentrations close to its physiological levels induces Ca(2+) influx in T cells, whereas PI(3,4)P(2), PI(4, 5)P(2), and PI(3)P have no effect on [Ca(2+)](i). This Ca(2+) entry mechanism is cell type-specific as B cells and a number of cell lines examined do not respond to PI(3,4,5)P(3) stimulation. Second, inhibition of PI 3-kinase by wortmannin and by overexpression of the dominant negative inhibitor Deltap85 suppresses anti-CD3-induced Ca(2+) response, which could be reversed by subsequent …

New World Nine-Primaried Oscine Relationships: Constructing A Molecular Framework, John Klicka, Kevin P. Johnson, Scott M. Lanyon

Ornithology Program (HRC)

Historically, a paucity of comparative morphological characters has led to much debate regarding relationships within and among the major lineages of New World nine-primaried oscines. More recently, DNA-DNA hybridization studies have provided novel and testable hypotheses of relationships, although no consensus has been reached. For 40 songbird taxa, we obtained 1,929 base pairs (bp) of DNA sequence from the mitochondrial cytochrome-b (894 bp) and NADH dehydrogenase subunit 2 (1,035 bp) genes. Phylogenetic analyses confirm the monophyly of this assemblage as traditionally defined. The lineages delineated historically on morphological grounds are retained; finches (Fringillinae) are sister to a well-supported clade …

The Skn7 Response Regulator Of Saccharomyces Cerevisiae Interacts With Hsf1 In Vivo And Is Required For The Induction Of Heat Shock Genes By Oxidative Stress, Desmond C. Raitt, Anthony L. Johnson, Alexander M. Erkine, Kozo Makino, Brian Morgan, David S. Gross, Leland H. Johnston

Scholarship and Professional Work – COPHS

The Skn7 response regulator has previously been shown to play a role in the induction of stress-responsive genes in yeast, e.g., in the induction of the thioredoxin gene in response to hydrogen peroxide. The yeast Heat Shock Factor, Hsf1, is central to the induction of another set of stress-inducible genes, namely the heat shock genes. These two regulatory trans-activators, Hsf1 and Skn7, share certain structural homologies, particularly in their DNA-binding domains and the presence of adjacent regions of coiled-coil structure, which are known to mediate protein–protein interactions. Here, we provide evidence that Hsf1 and Skn7 interact in vitro and …

Cell Cycle-Dependent Binding Of Yeast Heat Shock Factor To Nucleosomes, Christina Bourgeois Venturi, Alexander M. Erkine, David S. Gross

Scholarship and Professional Work – COPHS

In the nucleus, transcription factors must contend with the presence of chromatin in order to gain access to their cognate regulatory sequences. As most nuclear DNA is assembled into nucleosomes, activators must either invade a stable, preassembled nucleosome or preempt the formation of nucleosomes on newly replicated DNA, which is transiently free of histones. We have investigated the mechanism by which heat shock factor (HSF) binds to target nucleosomal heat shock elements (HSEs), using as our model a dinucleosomal heat shock promoter (hsp82-ΔHSE1). We find that activated HSF cannot bind a stable, sequence-positioned nucleosome in G₁-arrested …

Expression And Function Of Hoxc5 And Hoxc6 In The Murine Mammary Gland, Silvia Alejandra Garcia-Gasca

MUSC Theses and Dissertations

Homeotic genes encode transcription factors, believed to regulate cell proliferation, differentiation, as well as cell migration to create positional identities during embryogenesis. In the mouse, the Hox complex consists of at least 39 genes, organized into four clusters, in four different chromosomes. Hoxc5 and Hoxc6 are adjacent genes located in chromosome 15, and are expressed in the developing somites of the thoracic region and central nervous system with overlapping patterns. Both Hoxc5 and Hoxc6 are also expressed in the mammary gland. This study demonstrates that a targeted disruption of the Hoxc6 gene results in a failure of ductal development in …