Amino Acids, Peptides, and Proteins Commons^™

Ricin B Chain-Insulin Fusion Protein Immunomodulation Of Type 1 Diabetes, James Edward Carter Iii

Loma Linda University Electronic Theses, Dissertations & Projects

Type 1 diabetes mellitus (T1D) is a debilitating chronic inflammatory disease of the insulin-producing pancreatic islet β-cells that results from a combination of genetic and environmental factors. Attempts to suppress Th1-mediated autoimmune diseases such as T1D by mucosal delivery of autoantigens for immunotolerization have yielded only partial success. Attainment of satisfactory levels of sustained immunological tolerance remains to be accomplished. To restore self-tolerance requires delivery of sufficient amounts of autoantigen to stimulate regulatory T helper cells that function to survey the gut and induce tolerance to consumed antigens such as food. Oral delivery of autoantigens has previously been shown to …

Fetal Cocaine Exposure Causes Epigenetic Changes In The Rat Heart, Kurt D. Meyer

Loma Linda University Electronic Theses, Dissertations & Projects

Cocaine abuse continues to be prevalent in the United States and other industrialized nations, in addition to the negative health effects that cocaine abuse has on the user, a mother who uses cocaine while pregnant also exposes the developing fetus to cocaine. Although there have been many studies of the effects of cocaine on the adult heart, studies of cocaine on the fetal heart and its potential delayed pathophysiological effects on cardiac function in adult offspring are extremely limited. The studies of the present project sought to enhance the understanding of the effect of cocaine exposure on the fetal heart …

Localization And Expression Of The Aer Receptor In Escherichia Coli, Daniel Salcedo

Loma Linda University Electronic Theses, Dissertations & Projects

In Escherichia coli, chemotactic movement towards an energetically-favorable environment is mediated by five transmembrane chemoreceptors. These sensory proteins respond to numerous environmental signals, including amino acids, sugars, and pH. The aerotaxis receptor, Aer, is an intracellular sensor that responds to oxygen concentration and other parameters affecting cellular energy levels. Bacterial chemotaxis receptors form dimeric signaling units that organize into tetramers and hexamers and form large clusters at the cell poles. A cluster arrangement could increase receptor sensitivity by lateral communication between dimers, thus amplifying the signal from one dimer. We have shown that Aer forms dimers, trimer of dimers, …

Arginine Vasopressin And Male Attachment: A Marital And Family Therapy Perspective, Calvin James Thomsen

Loma Linda University Electronic Theses, Dissertations & Projects

Social neuroscience offers a promising way to understand some dimensions of adult attachment. Arginine vasopressin (AVP) is a neuropeptide with significant implications for human social behavior and it provides an important testing ground to explore links between social/interpersonal neurobiology and attachment. It has a distinctive impact on the social/relational behavior of certain male animals, most notably prairie voles. It fosters monogamy, creates attachment to both mate and offspring, and increases affiliation and a desire for physical proximity with other animals of the species. There has been much speculation that it might play a similar role with human males. This study …

Novel Binding Domains Mediate Binding Of Hpv 16 E6 To Fadd And Procaspase 8, Sandy S. Tungteakkhun

Loma Linda University Electronic Theses, Dissertations & Projects

To evade the host response to infection, viruses have developed means to survive and propagate. HPV 16, a causative agent of cervical cancer and of some cases of oropharyngeal cancers, is one example. We have reported that the early viral protein E6 binds to proteins necessary for propagation of the apoptotic signal following receptor/ligand interactions, such as those mediated by FADD DED and procaspase 8 DED. E6 expression leads to the dose-dependent accelerated degradation of FADD and the protection of E6-expressing cells from Fas-induced apoptosis. Surprisingly, the splice isoforms of E6, E6_large and E6*, affect the stability of procaspase …

Radiation-Induced Glutamate Transport Alterations In Neuron-Astrocyte Coupling, Martha Celia Sanchez

Loma Linda University Electronic Theses, Dissertations & Projects

Exposure of the central nervous system (CNS) to ionizing radiation is known to result in behavioral, cognitive, and motor deficits - effects similar to those seen in many neurodegenerative disorders. Neurons and astrocytes, two principal cell types in the brain, coexist as an interdependent metabolic unit via the neurotransmitter glutamate. Disruption of this metabolic coupling would have widespread effects within the CNS, therefore it is hypothesized that ionizing radiation impairs glutamate transport and metabolism, and increases oxidative stress, ultimately impairing neuron-astrocyte coupling. We propose to investigate the mechanism and determine the impetus for radiation-induced neurotoxicity by measuring the temporal sequence …

The Association Between Lifestyle Factors And Inflammatory Markers, Kerry Ann Stonebrook

Loma Linda University Electronic Theses, Dissertations & Projects

Background: Cardiovascular disease (CVD) is the leading cause of death for both men and women in the United States. While smoking, high blood pressure, and elevated cholesterol levels are established risk factors for CVD, inflammation is being evaluated as a potential independent risk factor. A key cytokine regulator of the inflammatory response, interleukin-1 (IL-1), has emerged as playing a particularly important role at the genetic level in determining the degree to which the inflammation pathway is turned on. How an individual’s genetic make-up affects inflammation, CVD risk, and response to lifestyle intervention is an area of research that is in …

Gene Expression In The Mouse Placenta: Developmental And Stress Responses, Ciprian P. Gheorghe

Loma Linda University Electronic Theses, Dissertations & Projects

Successful placental development is crucial for optimal growth, maturation, and survival of the embryo/fetus. Placental failure and placental pathology contributes to both morbidity and mortality of the fetus. We sought to understand normal placental development and also placental responses to stress using oligonucleotide microarray technology. To examine genetic aspects of normal placental development, we investigated gene expression patterns in the murine placenta at embryonic day 10.5 (E10.5), E12.5, E15.5, and E17.5. Hypoxia has been identified as a major stressor in placental and fetal development. In order to comprehend more completely hypoxic stress responses we sought to measure gene expression changes …

The Potential Role Of Ledgf/P75 In Prostate Cancer, Tracy Ruth Daniels

Loma Linda University Electronic Theses, Dissertations & Projects

The serum autoantibody repertoire from cancer patients is currently being exploited for the identification of tumor associated antigens (TAA) and the design of TAA arrays. Such arrays would facilitate autoantibody profiling and potentially aid in the serological diagnosis and prognosis of tumors. The goal of this study was to identify and characterize prostate-specific TAA. We observed that while the general frequency and titers of autoantibodies in PCa patients were relatively similar to those in matched controls, significant differences could be detected between the two groups in the autoantibody response to the lens epithelial-derived growth factor p75 (LEDGF/p75). LEDGF/p75 is a …

Enterotoxin B Subunit Lectins As Adjuvants For Improvement Of Mucosal Vaccine, Nak-Won Choi

Loma Linda University Electronic Theses, Dissertations & Projects

In comparison with whole organism vaccines, subunit vaccines may be safer for immunization but may lack sufficient immunogenicity to provide complete immunity to the pathogen. To resolve this problem, bacterial and plant enterotoxin B subunit adjuvants containing a variety of receptor-binding properties were used to enhance the immunogenicity of rotavirus subunit vaccines. Enterotoxin B subunit adjuvants were employed to enhance protection against virus infection. Pentameric cholera toxin B subunit (CTB), shiga toxin-1 B subunit (STB) and monomeric ricin toxin B subunit (RTB) molecules were genetically linked to a 90 amino acid peptide from the simian rotavirus (SA11) nonstructural protein NSP4 …

Il-10 And Alveolar Bone Loss, Abdulaziz Saud Al-Rasheed

Loma Linda University Electronic Theses, Dissertations & Projects

Interleukin-10 (IL-10) is a cytokine with anti-inflammatory activities. IL-10 knockout (KO) mice exhibit severe intestinal inflammation in the presence of normal gut flora. We hypothesized that IL-10 KO mice would also be susceptible to inflammatory periodontal disease resulting in alveolar bone loss (ABL). The purpose of this study was to compare naturally occurring ABL in IL-10 KO and wild type (WT) mice. Twelve IL-10 KO and 12 WT mice, age-(7 months) and sex-(male) matched, were used. Half of the mice were on 129/SvEv and half on C57BL/6J background. Animal heads were defleshed and treated to remove all organic material. ABL …

Effect Of Monounsaturated Fat Rich Almonds On Hemostatic And Inflammatory Factors In Healthy Adults, Kristianne M. Connell

Loma Linda University Electronic Theses, Dissertations & Projects

Background: The frequent consumption of nuts is inversely associated with the incidence of cardiovascular disease. Nuts are known to decrease the risk of cardiovascular disease by reducing serum total and low-density lipoprotein (LDL) cholesterol. Markers of inflammation including C-reactive protein, E-selectin and interleukin-6 have been proposed to be newer risk factors for cardiovascular disease. However, the influence of nuts such as almonds on markers of inflammation and hemostasis that influence cardiovascular disease risk is not currently known.

Objective: The objective of this study was to determine the effect of almond consumption on markers of inflammation and hemostatic factors in healthy …

Effects Of A Serine 364 To Proline Mutation Of The Connexin43 Protein In Transgenic Mice, Chia-Ling Nhan-Chang

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Glucocorticoid Regulation Of Insulin Like Growth Factor Binding Protein-5 Gene Transcription In Human Osteoblasts, Xiaoying Wang

Loma Linda University Electronic Theses, Dissertations & Projects

Glucocorticoids (GCs) inhibit bone formation in vivo and inhibit osteoblast proliferation and collagen synthesis in vitro. These effects may be mediated by alterations in the insulin-like growth factor (IGF) system. In the present study of normal human osteoblast-like (HOB) cells, we tested the hypothesis that dexamethasone (Dex) inhibits the expression of IGF binding protein-5 (IGFBP-5). Dex decreased IGFBP-5 mRNA levels to 54% of control after 4 hr. Dex did not modify the decay of IGFBP-5 mRNA in transcriptionally arrested osteoblast cells. Dex decreased IGFBP-5 hnRNA levels to 67% of control after 2 hr, and the activity of the human IGFBP- …

Studies On The Purification And Role Of Igfbp-5 Protease In Bone, H. Garrett Rush Thompson

Loma Linda University Electronic Theses, Dissertations & Projects

Osteoporosis is a disease characterized by low bone density and deterioration of mineralized bone leading to enhanced susceptibility to fracture. Several growth factors have been implicated in the coupling of formation to resorption during the bone remodeling process. The net bone forming activity of many growth factors has prompted numerous studies focused on the regulation of osteoblast cell proliferation, differentiation and activity. The current study focuses on the insulin-like growth factor (IGF) system, an important growth factor system involved in the regulation of bone formation and bone resorption.

IGF binding protein -5 (IGFBP-5), the most abundant IGF binding protein in …

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 …

Regulation Of Connexin43 By Phosphorylation, Maithili M. Shah

Loma Linda University Electronic Theses, Dissertations & Projects

Gap junctions play a crucial role in embryogenesis, especially of the heart where connexin43 is thought to be important for its formation as well as synchronized contraction. Several reports have shown that connexin43 protein is phosphorylated on serine residues in vitro and in vivo.

Studies performed in our laboratory have demonstrated that cell-to-cell communication in cells expressing connexin43 can be controlled rapidly and reversibly by microinjection of active protein kinases or phosphatases that target serine or threonine residues. Phosphorylation by cAMP-dependent protein kinase (PKA) seems to favor channel opening, whereas the effect of protein kinase C (PKC) on channel gating …

The Role Of Gap Junctions In Congenital Diseases Of The Heart, Scott Henry Britz-Cunningham

Loma Linda University Electronic Theses, Dissertations & Projects

Background. Gap junctions are thought to have a crucial role in the synchronized contraction of the heart and in embryonic development. Connexin43, the major protein of gap junctions in the heart, is targeted by several protein kinases that regulate myocardial cell-cell coupling. We hypothesized that mutations altering sites critical to this regulation would lead to functional or developmental abnormalities of the heart.

Methods. Connexin43 DNA from 25 normal subjects and 30 children with a variety of congenital heart diseases was amplified by the polymerase chain reaction and sequenced. Mutant DNA was expressed in cell culture and examined for its effect …

Regeneration In Periodontal Defects With Rhbmp-2 : A Dosage Study, Paola Guglielmoni

Loma Linda University Electronic Theses, Dissertations & Projects

Bone morphogenetic proteins (BMPs) have been shown to induce bone formation in ectopic and orthotopic sites. This inductive capability has led to their evaluation as possible adjuncts in periodontal reconstructive therapy. Indeed, studies have reported periodontal regeneration following surgical implantation of recombinant human BMP-2. This study evaluated regeneration of alveolar bone and cementum following periodontal reconstructive surgery including implantation of a construct consisting of sterile lyophilized rhBMP-2 in buffer adsorbed onto an absorbable collagen sponge. Critical size mandibular supra-alveolar periodontal defects were surgically created, and an incomplete block design was used to evaluate the regenerative potential of rhBMP-2 at 0.05, …

A Model Using Radiation And Pws4-Htnf-Α Gene Therapy For Treatment Of Glioblastomas, Angelo G. Baher

Loma Linda University Electronic Theses, Dissertations & Projects

The efficacy of radiotherapy for cancer is limited by the dose that can be safely delivered to the tumor without causing debilitating side effects. In addition, successful treatment of highly malignant tumors such as glioblastomas is likely to require adjunctive therapies to enhance tumor response to radiation. Previous studies have shown immunomodulation and a synergestic reduction in tumor volume of malignant tumors when tumor necrosis factor-α (TNF-α) protein is administered prior to radiation. The major goal of the present investigation was to evaluate the efficacy of pWS4-human TNF-α (pWS4-hTNF-α), a new plasmid construct that expresses human TNF-α protein, together with …

Cellular Responses In Escherichia Coli To Lethal And Sublethal Doses Of Ozone, Indira Ruth Komanapalli

Loma Linda University Electronic Theses, Dissertations & Projects

Ozone is a major component of photochemical smog. High levels of this pollutant, sufficient to affect human health are found in many urban areas worldwide. Though limited studies in humans are supported by extensive findings from animal experiments, a difficulty in interpreting the results of these experiments has lead to an ambiguity on the biochemical mechanism of ozone toxicity. To elucidate the mechanism by which ozone causes cell damage and eventual cell death we conducted a comprehensive study using Escherichia coli K-12 as a model.

Studies on the comparative inactivation of bacteriophage lambda (λ), Escherichia coli, and Candida albicans …

Study Of The Hiv-1 Gene Regulatory Proteins Tat And Rev By The Two-Hybrid System In Yeast, David Allen Elkins

Loma Linda University Electronic Theses, Dissertations & Projects

Tat and Rev, small proteins encoded by the Human Immunodeficiency Virus type 1 (HIV-1), regulate its pattern of gene expression within infected cells. Tat increases transcription from the integrated pro virus by approximately a thousand-fold; Rev effects a shift in the pattern of splicing of the viral mRNA. Both are likely to interact with cellular proteins in executing their respective functions. Tat has additional activities (including neurotoxicity and inhibition of lymphocyte activation) which may be extraneous to its viral functions.

In order to identify cellular proteins interacting with Tat and Rev, the genes for both were cloned into plasmid vectors …

Bone Morphogenetic Proteins And Periodontal Repair, Michael B. Lee

Loma Linda University Electronic Theses, Dissertations & Projects

For over thirty years now, research has been carried out to isolate and purify bone morphogenetic protein (BMP), a substance which has been shown to induce heterotopic bone formation in various animal species. Recent advances in the fields of developmental biology, molecular biology and genetics, have shown that the BMPs not only are responsible for postfetal bone induction (including normal bone remodeling, healing and repair), but are also critical during embryogenesis - not only in regards to the skeletal system, but quite possibly in the morphogenesis and pattern formation of other tissues and organs as well.

Due to their bone …

Transcriptional Regulation Of Insulin-Like Growth Factor : Binding Protein-4 By Protein Kinase A And Protein Kinase C Signal Transduction Pathways In Human Bone Cells, Kuk-Wha Lee

Loma Linda University Electronic Theses, Dissertations & Projects

The Insulin-like Growth Factor (IGF) system is an important local regulator of osteoblast proliferation, the primary determinant of bone formation. Six IGF Binding Proteins (IGFBPs) either inhibit or enhance IGF actions. Previous studies have shown that IGFBP-4 is an important negative regulator of osteoblast cell proliferation and that agents such as PTH which increase intracellular cAMP significantly increase expression of IGFBP-4 at the protein and mRNA levels. The underlying molecular mechanism which accounted for IGFBP-4 expression had not been determined and was the focus of my dissertation. Agents which increase intracellular cAMP rapidly increased IGFBP-4 mRNA levels. Nuclear run-off experiments …

Effects Of Furosemide And Oleic Acid On Thyroxine Binding To Isolated Pairs Of Thyroxine Binding Serum Proteins, Deborah Hustead

Loma Linda University Electronic Theses, Dissertations & Projects

Dosage dependent binding inhibition and redistribution of thyroxine (T₄) between three pairs of thyroxine binding serum proteins, TBG-TTR, TBG-albumin and TTR-albumin, by furosemide (0.0 to 1.0 mol/L) and oleic acid (0.0 to 0.10 mol/L) were studied using equilibrium dialysis with purified binding proteins at concentrations 1/200 of levels in normal human sera, separated across the dialysis membrane and competing for T₄.

Furosemide (1.0 mol/L) reduced TBG bound T₄ in both the TBG-TTR system and TBG-albumin system (>90% decrease) and inhibited T₄ binding to TTR in the TTR-albumin system (68% decrease) and to albumin …

The Production And Characterization Of A Monoclonal Antibody To A Naturally Occurring Aminomalonic Acid Epitope And A Comparison With An Antibody To A Synthetically Derived Aminomalonic Acid Epitope, James L. Gulley

Loma Linda University Electronic Theses, Dissertations & Projects

The goal for this project is to undertake the first step in the study of blocking metastasis by a monoclonal antibody. The long range goal of this line of research is to study a novel mechanism for the blocking of tumor metastasis in general and prostatic cancer metastasis in particular. The problem that this addresses is the growing number of cases of prostatic cancer in the increasingly aging male population. This cancer is not lethal unless it metastasizes, yet there is no cure for the metastatic disease. The inherent specificity of a monoclonal antibody combined with the uniqueness of the …

Signal Transduction In Bacterial Chemotaxis, Edward Heath Rowsell

Loma Linda University Electronic Theses, Dissertations & Projects

This study investigated the site of ATP utilization in the signal transduction pathway of bacterial chemotaxis and localized the point of convergence of a methylation-independent system of chemotaxis with the methylation-dependent system. The identity of the signal originating from the phosphotransferase system was investigated by substituting the fructose-inducible HPr-like protein FPr for HPr in transport and chemotaxis. In addition, a novel chemoattractant, glycerol, was identified for Salmonella typhimurium. Histidine-auxotrophic S. typhimurium strains ST23 (hisF) and ST171 (hisF cheB) were depleted for ATP. The times required for the bacteria to adapt to a step increase in serine, …

Aerotaxis In Bacillus Subtilis, Laurence Samuel Wong

Loma Linda University Electronic Theses, Dissertations & Projects

B. subtilis, like Escherichia coli and Salmonella typhimurium, responded to a step increase in oxygen concentration by swimming smoothly (~ 35 s duration) and to a decrease in oxygen by tumbling. In a spatial gradient of oxygen in liquid media, a band of cells congregated near the air interface. Aerotaxis required a functioning respiratory chain. Adaptation of B. subtilis, E. coli and S. typhimurium to media containing amino acids requires methylation of receptors/methyl-accepting chemotaxis proteins. Adaptation to oxygen and phosphotransferase sugar substrates in B. subtilis was dependent on methylation, unlike similar adaptation in E. coli and S. typhimurium. …

Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure

Loma Linda University Electronic Theses, Dissertations & Projects

The best understood functional activity of the pineal gland is its diurnal production of melatonin in response to environmental lighting cues. Several enzymes of the melatonin pathway respond to daily photoperiod changes, for example hydroxyindole-O-methyltransferase (HIOMT) and serotonin N-acetyltransferase (SNAT). Increased levels of the glycolytic enzyme neuron-specific enolase (NSE) are thought to reflect increased physiological demands placed on neurons and neuroendocrine tissues. Homodimer non-neuronal enolase isoenzyme (NNE) is immunolocalized to cells, and the hybrid enolase (consisting of subunits from NSE and NNE) has been seen in cerebellar stellate and basket cells. Although not rate limiting, concentrations of both NSE and …

An Analysis Of Protein-Ligand Interactions For Enzyme Ii-Mannitol From Escherichia Coli, Brent Lee Wood

Loma Linda University Electronic Theses, Dissertations & Projects

Enzyme II^mtl of Escherichia coli was purified from mtlA-overexpressing E. coli strain LJ1112 extraction of isolated membranes with deoxycholate, followed by hexyl agarose and ω-amino hexyl agarose chromatography in Lubrol PX. A 10-fold increase in total pure protein and 2.5-fold increase in specific activity over previously reported procedures was obtained. Tryptic fragments of Enzyme II^mtl were also purified and identified as the membrane and cytoplasmic domains by protein sequencing and SDS-PAGE. The fluorescence spectrum of Enzyme II^mtl suggested that two populations of tryptophan residues existed with emission maxima at 322 and 344 nm, corresponding to buried …