Life Sciences Commons^™

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 …

The Roles Of Ca2+ And Camp In The Nematocyst Discharge Of The Sea Anemone Tentacle, Veysel Haktan Ozacmak

Loma Linda University Electronic Theses, Dissertations & Projects

The phylum Cnidarians are aquatic animals, including jellyfish, hydra, sea anemones, and corals. They are the simplest metazoans having a nervous system and are diploblastic. Cnidarians are obligate predators that capture prey using specialized stinging cells called cnidocytes. The cnidocyte contains a nematocyst, which is a capsule containing an inverted, hollow tubule. Prey contacting the tentacle triggers the nematocyst tubule to rapidly evert; a process called discharge. The everting tubule penetrates and envenomates the prey, which is carried to the mouth by tentacle movements.

Generally both chemical and mechanical stimuli are needed to trigger discharge. The cnidocytes, in sea anemones, …

Chronic Hypoxia, Exercise Training, And Skeletal Muscle Capillarity: Angiogenic Regulation And Morphological Consequences, Ivan Mark Olfert

Loma Linda University Electronic Theses, Dissertations & Projects

Angiogenesis is important in health and disease. In particular, exercise training is known to increase skeletal muscle capillarity, providing there is sufficient training intensity. The stimulus for this may be intracellular hypoxia activating angiogenic growth factor gene expression. Acute hypoxia alone has been shown to increase the gene expression of several key angiogenic regulators, e.g. vascular endothelial growth factor (VEGF) and to a lesser degree transforming growth factor-β1 (TGF-β1), basic fibroblast growth factor (bFGF), and thrombospondin-1 (TSP-1), an endogenous negative angiogenic regulator. Paradoxically, however, chronic hypoxia is generally not found to increase mammalian skeletal muscle capillarity. Accordingly, we hypothesized that …

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- …

Towards Gene Therapy Of Parkinson’S Disease: Implantation Of Ruc-Gdnf Secreting Mammalian Cell Lines Into Rat Brain, Hua Liu

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to develop a new approach for monitoring the function of implanted cells by a Renilla luciferase -glial cell line derived neurotrophic factor (RUC-GDNF) fusion protein in CSF. The RUC-GDNF protein is expected to report GDNF secreted from the cell by bioluminescence through luciferase activity.

Current ex vivo gene therapy using GDNF is limited by lack of a monitoring mechanism to determine the expression of GDNF once transformed cells or vector DNA are injected into animal models. Since the therapeutic concentration of GDNF secreted into cerebrospinal fluid (CSF) by implanted cells is too low for …

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, …

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 …

Identification And Characterization Of The Cis-Acting Elements Around The Murine Cd4 Cnhancer, Xin Dong

Loma Linda University Electronic Theses, Dissertations & Projects

The cluster determinant 4 (CD4) molecule is a transmembrane glycoprotein. CD4 is essential for normal T helper cell function and plays an important role in T cell development and activation. CD4 is encoded by a single gene located on chromosome 6 in the mouse and chromosome 12 in the human. Both human and murine CD4 genes are divided into ten exons spanning more than 25 kb and have a large non-coding region in the first and third intron. CD4 gene expression is controlled primarily at the transcriptional level during T cell development and activation.

An enhancer has been identified approximately …

Mechanisms Of Calcium Buffering And Aging In Neurons: Testing The Limits Of Homeostasis, William James Pottorf Ii

Loma Linda University Electronic Theses, Dissertations & Projects

Intracellular calcium ([Ca²⁺]i) is an ubiquitous second messenger that integrates multiple and diverse neuronal pathways that include development and maturation, gene expression, synaptic plasticity, transmitter release, excitability, and even cell death. Upon neuronal excitation the [Ca²⁺]i increases rapidly and the calcium buffering system reacts quickly to restore [Ca²⁺]i to basal levels in order to reset the cell for the next stimulus and avoid prolonged exposure to cytotoxic levels of high [Ca²⁺]i. The aging process appears to causes multiple changes in the ability of neurons to regulate [Ca²⁺]i homeostasis and an …

Molecular Cloning And Analysis Of The Modification Genes Of The Kpnbl Restriction- Modification System Of Klebsiella Pneumoniae Strain Gm236, Vernon Robert Chin

Loma Linda University Electronic Theses, Dissertations & Projects

The KpnBl restriction-modification (R-M) system has been recognized for some time in Klebsiella pneumoniae strain GM236. Previously the restriction subunit (hsdR_kpmBI) was cloned and sequenced, based on the sequence infonnation the KpnBl RM system was suspected to be either a type I or type III R-M system In this project the modification genes of KpnBl were cloned into a pMECA plasmid by using a modification expression method. The modification genes were identified on an 8.2 kb EcoRl fragment from a chromosomal library of the GM236 strain. The complete 8.2 kb fragment was sequenced and …

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 …

Post-Treatment Evaluation Of Isometric Function Of The Elevator Muscles, Margaret Barbara Kowalczyk

Loma Linda University Electronic Theses, Dissertations & Projects

This study mainly examined neuromuscular function, occlusal index, and centric relation-centric occlusion (CR-CO) discrepancy of 23 orthodontically treated patients. Phase I, craniofacial anomalous, and orthognathnic surgery cases were excluded from the study. Record taking was done in 2 sessions: (1) at the time of deband and (2) 3-4 months later. Records taken at each session included facial and intraoral photographs, impressions, CR wax bites, a facebow, and surface EMG (sEMG) recordings.

For the sEMG recordings, electrodes were placed on the upper hyoid, masseter, and anterior temporalis muscles. Subjects were asked to perform numerous tests; these included baseline, clenching to test …

Identification And Characterization Of Control Elements Within The Murine Cd4 Gene, Zhong Deng

Loma Linda University Electronic Theses, Dissertations & Projects

The control of CD4 gene expression is essential for T lymphocyte development. Since the molecular mechanism for the control of CD4 gene expression during T cell development had not been elucidated, a study of the factors that control CD4 gene expression may lead to further. Toward these goals, we have made a series of recombinant DNA constructs to define the cis-acting transcriptional control elements in the murine CD4 locus that control CD4 gene expression during T cell development. In this study, we have identified multiple cis-acting control elements, which are critical for regulating the expression of the murine …

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 …

Molecular Cloning Of The Cdna For Porcine Parotid Hormone, Qian Zhang

Loma Linda University Electronic Theses, Dissertations & Projects

It has been found that parotid glands secrete a factor into blood that stimulates dentinal fluid movement, which in turn, prevents the development of dental caries. This factor, designated as parotid hormone, has been isolated from porcine parotid glands and its partial amino acid sequence has been determined. This study was developed to isolate and identify the cDNA sequence for porcine parotid hormone.

A porcine parotid cDNA library was constructed and hybridized with oligo probes designed based on the partial amino acid sequences of the isolated porcine parotid hormone. Over 100 positive clones were isolated and the complete nucleotide sequences …

First Principles Of Physio-Informatic Systems: Neurocosmology, David Jay Warner

Loma Linda University Electronic Theses, Dissertations & Projects

Physio-informatics is a new systems model for linking human physiologic systems to information systems in the most general way. Physio-informatics is used here to denote a systems based, physiologically robust reference architecture for designing and refining interactive human-computer interface systems in ways that increase operational throughput of information. In this dissertation, a systems model for interactive human-computer interface systems is developed. This model is a physiologically based reference architecture for designing and developing interactive human computer interface systems to match the human nervous system’s ability to transduce, transmit, and render to consciousness the necessary information to interact intelligently with information. …

Telomerase Activity In Prostatic Fluid And Tissue As A Marker For Prostate Cancer, Zhilian Wang

Loma Linda University Electronic Theses, Dissertations & Projects

Telomerase is a ribonucleoprotein enzyme that is able to add telomeric repeats to the ends of eukaryotic DNA to stabilize chromosomes. Telomerase is active in germline cells, stem cells and tumor cells, but not in most human somatic cells. In this study we report the extended use of the Telomeric Repeat Amplification Protocol (TRAP) assay for the detection of telomerase activity in prostate needle biopsy specimens and freshly collected prostatic fluid. Clinical application of a newly developed PCR-ELISA telomerase assay method is also evaluated. Multiple sextant needle biopsy specimens from 56 subjects and prostatic secretion specimens from 72 subjects, with …

Periradicular Response Of Immunodeficient Rats To Mechanical Pulpal Exposure, James E. Stich

Loma Linda University Electronic Theses, Dissertations & Projects

Periradicular lesions develop as a result of the interaction between root canal irritants and the immune system. The purpose of this study was to investigate the periradicular response of immunodeficient rats to their oral flora. Twenty Sprague-Dawley rats received a total body irradiation dose of 750 cGy one week prior to the investigation. The pulps of the mandibular first molars of these animals and six nonirradiated rats were exposed mechanically with a ½ round bur and left open to the oral cavity. Additional irradiation (350 cGy) was administered bi-weekly to maintain immunosuppression. Periradicular specimens were obtained after two and four …

Intracellular Traits Of Chimeric Trnalys3-Ribozymes And Their Inhibition Of Hiv, Zongli Chang

Loma Linda University Electronic Theses, Dissertations & Projects

Host tRNALYs3is the primer recruited by HIV-1 for initiating reverse transcription. When ribozymes targeted upstream of the primer binding site of the HIV-1 genome are tethered to the 3' end of the tRNALYs3, it is expected that the tRNA will carry the ribozymes into the virions. We made constructs that express chimeric tRNALYs3- ribozymes from internal tRNA promoters. These chimeras were also adjoined downstream of a U6 promoter, resulting in a hybrid U6/tRNA expression cassette with extragenic U6 and intragenic tRNA promoters. Juxtaposition of the tRNA and U6 promoters significantly enhanced expression levels compared to the tRNA promoter alone. A …

Factors Associated With Healthy Eating: Attitudes, Cultural Adherence, And Snacking Behavior Among Korean-American Adolescents, Kyoung Eun Oh

Loma Linda University Electronic Theses, Dissertations & Projects

Adolescents have increased nutrition needs and report frequent meal skipping and snacking, but there are few studies that examine the determinants of unhealthy eating, especially among ethnic minority groups. This study investigated dietary intake and snacking behavior among Korean-American adolescents in the Los Angeles area. We determined the relationship between dietary fat intake and overall quality of the diet as assessed by two healthy eating indices: the Healthy Eating Index (HEl) and Mean Nutrient Adequacy Ratio (MNAR). HEl assessed degree of compliance to Food Guide Pyramid and Dietary Guidelines for Americans while MNAR assessed nutrient consumption compared to Recommended Dietary …

Predicting Milk And Soft Drink Consumption Among Female Adolescents Using The Theory Of Planned Behavior, Nada Osman Kassem

Loma Linda University Electronic Theses, Dissertations & Projects

A total of 756 female adolescents, aged 13 to 18 years, from five public high schools in Antelope Valley Union High School District located in North Los Angeles County participated in this study between February 1999 and March 1999. The ethnic composition was 53.3% White/Anglo Americans, 19.3% Hispanics or Latinos and 10.2% Black/African Americans. The constructs of the Theory of Planned Behavior (attitude, subjective norm, and perceived behavioral control and their underlying beliefs) were assessed to determine the predictors of low-fat milk and regular soda consumption. A cross-sectional design with group-administered questionnaires was utilized.

Most participants (89.6%, n = 636) …

Client-Centered Versus Traditional-Directive Educational Approach: A Randomized Study Of Exercises And Perceived Control Among Patients With Type 2 Diabetes, Melissa D. Olfert

Loma Linda University Electronic Theses, Dissertations & Projects

A patient’s adherence to self-management therapies in diabetes strongly influences health outcomes, health care utilization, and ultimately health care costs. Engaging in regular exercise therapy reduces risk factors associated with type 2 diabetes. The purpose of this randomized prospective study was to determine if a client-centered approach (CCA) toward diabetes education, verses a traditional-directive approach (TDA), would improve exercise participation, perceived control, intention to exercise, and glycemic control in patients with type 2 diabetes.

Fifty-nine type 2 patients were randomized into two groups: CCA and TDA. Diabetes education in the CCA group provided empowerment toward acquiring knowledge, skills, and responsibility …