Medicine and Health Sciences Commons^™

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 …

A Cross-Sectional Study Examining Lifestyle And Rheumatoid Arthritis, Leslie Nazaroff

Loma Linda University Electronic Theses, Dissertations & Projects

Objective. Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects the synovial joints. RA affects 0.5-2% of the population. Though it is predominantly a progressive disease, adjunct therapy may slow the destructive pathway or alleviate affiliated symptoms. This study examined the effects of lifestyle (diet and exercise) and self-efficacy on symptoms of RA as measured by disease activity and health satisfaction.

Methods. Seventy-five RA patients (77% female) from the Loma Linda University Faculty Medical Offices, Rheumatology Department completed self-assessment surveys on their lifestyle practices and RA affliction. Disease symptoms and activity were assessed with the Arthritis Impact Measurement …

Establishing Norms For A Mexican Group Using Ricketts, Steiner And Arnett Analyses, Mauricio Gonzalez Balut

Loma Linda University Electronic Theses, Dissertations & Projects

Most existing cephalometric analyses are based on norms for the Caucasian population. Therefore, they cannot be properly applied for Mexican or Hispanic patients. Ethnic variations in the normal positions of the maxilla and mandible influence and alter the diagnosis and treatment plan for each of the different type of malocclusions. Previous studies have addressed the difference between the Caucasian norms and the Hispanic norms, this indicates the variety of their skeletal, dental and facial features.

It is the purpose of this study to establish specific cephalometric standards for the native Mexican group, using the Steiner and Ricketts analyses along with …

The Relationship Of The Incisive Canal To Maxillary Median Diastema, Jeffery S. Corbett

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to assess the relationship between the incisive canal and maxillary median diastema, and to identify an imaging method capable of documenting the geometry and dimensions of the incisive canal. The sample consisted of 59 dry skulls, 26 of which had a maxillary median diastema ranging in size from 0.1 mm to 2.8 mm (mean 1.0 mm, SD = 0.7 mm). Each skull had all of the permanent maxillary teeth present from first molar to first molar and lacked any apparent non-orthodontic condition that could have caused the diastema. Diastema width and canal diameter were …

Expression, Isolation And Purification Of Human Zona Pellucida Protein 3, Ting-Fung Chi

Theses and Dissertations in Biomedical Sciences

Mammalian fertilization involves interactions of sperm surface receptors with the ligands of the zona pellucida, an extracellular matrix surrounding the ovulated oocytes. In humans, the zona pellucida is composed of three major glycoproteins. One of them, ZP3, participates in the primary sperm binding and in the subsequent triggering of the spermatozoa's acrosome reaction. Studies on the role of this specific protein in the human fertilization process are hampered by the limited amount of available biologically functional proteins.

By use of a pcDNA 3.1(+) expression vector, a transfecting-vector was constructed containing a 1.3 kb histidine tagged hZP3 cDNA. This histidine tagged …

Leukemia Inhibitory Factor (Lif): Murine Preimplantation Embryo Development, Implantation Rates, And Skeletal Development, Michael Hayes Mitchell

Theses and Dissertations in Biomedical Sciences

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine which demonstrates perplexing physiological effects. It has been demonstrated that LIF is essential for implantation in mice. Little is known relating to the manner by which LIF effects pre-implantation and post-implantation development. The objectives of this project were to determine the effects LIF on pre-implantation development, to determine the effects that it may have on implantation rates, successful pregnancy rates, and resorption rates, and to determine the effects that LIF has on the skeletal development of mice. For the embryo transfer experiments, embryos were exposed to test compounds in the transfer medium …

Mouse Embryo Development In The Presence Of Capsaicin, Carlos Santiago Villar-Gosalvez

Theses and Dissertations in Biomedical Sciences

Capsaicin is the pungent agent found in hot peppers of the Capsicum genus. It is a potent neurotoxin that stimulates the degranulation and degeneration of C-afferent neurons. Capsaicin is widely used as a food condiment and medicine. Human exposure of capsaicin can exceed levels shown to be neurotoxic in laboratory animals. Additionally, capsaicin can cross the blood/placenta barrier and affect an embryo in utero. In order to assay the potential for toxicity to human embryos, mouse embryos were exposed to capsaicin and the effect of the capsaicin on embryo development was measured. Embryos were co-cultured in Krebs medium with 1% …

The Relation Of Weight Loss And Improved Fitness To Survival In Healthy Males, Joanna Lynn Bokovoy

Loma Linda University Electronic Theses, Dissertations & Projects

Obesity is a critical public health problem because of its prevalence, medical and psychosocial effects, and resistance to intervention. Weight loss in overweight individuals has been encouraged by the United States Public Health Service and by the medical community as a means for improving health. However, recent studies have suggested either positive or negative effects of weight loss on survival. It is possible that physical fitness may have a confounding effect, or be an effect modifier on survival in weight loss studies.

This study used Cox Regression analysis to address the separate and combined association of weight loss and improved …

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 …

Nursing Home Ownership And Public Policy: An Historical Analysis, K. R. Kaffenberger

Graduate Doctoral Dissertations

In the early days of the United States, care of the disabled elderly outside the home meant the public almshouse. By the 1920s, private, nonprofit homes for the aged were prevalent. More recently, private, for-profit facilities have grown to dominate the field.

For-profit ownership has been controversial. Underlying the controversy is the concern that quality might be lowered in order to enhance profit.

This study asks why most nursing homes are privately owned and why most privately owned nursing homes are operated for profit. It does so with reference to The Nonprofit Economy, in which Burton Weisbrod describes a …

Quantal Mechanisms Underlying Stimulation-Induced Augmentation And Potentiation, Hong Cheng

Electronic Theses and Dissertations

Repetitive stimulation of motor nerves causes an increase in the number of packets of transmitter ("quanta") that can be released in the ensuing period. This represents a type of conditioning, in which synaptic transmission may be enhanced by prior activity. Despite many studies of this phenomenon, there have been no investigations of the quantal mechanisms underlying these events, due to the rapid changes in transmitter output and the short time periods involved. To examine this problem, a method was developed in which estimates of the quantal release parameters could be obtained over very brief periods (3 s). Conventional microelectrode techniques …

Patient-Guided Investigation Of The Restoration Of Health Following Traumatic Brain Injury, Nancy Ann Carney

Dissertations and Theses

The development of emergency department medical interventions and the implementation of fast-transport trauma systems has decreased the rate of death resulting from traumatic brain injury (TBI). Without corresponding methods for long-term treatment and recovery, the prevalence of people disabled by TBI has increased, creating a growing public health problem. Investigations generated by physicians, rehabilitation programs, and social scientists, which attempt to associate standard measures of injury severity with outcome, leave unexplained variance in long-term functional status for persons with TBI.

The purpose of this investigation was to use persons with brain injury and their family members, to guide an analysis …

Acute Blood Pressure Responses To Static And Dynamic Exercise: Racial Differences, Reuben Leon Wright

Theses and Dissertations in Urban Services - Urban Education

African Americans have a higher incidence of hypertension than other racial groups. Furthermore, some research suggests that normotensive individuals who exhibit exaggerated blood pressure (BP) responses to exercise may be at risk for future hypertension. This study sought to determine if normotensive African Americans exhibited exaggerated BP responses to static exercise or dynamic exercise relative to Caucasian Americans and Asian Americans. Thirty normotensive subjects participated from each of the three racial groups (15 males and 15 females). Subjects held 30% of maximal voluntary contraction (right knee extension) for 3 minutes, and BP was recorded during the third minute. On a …

Pressure-Induced Intracellular Signaling In Isolated Arteries, Victor A. Miriel

Theses and Dissertations in Biomedical Sciences

The ability of cells to respond to mechanical stimuli has been studied through a variety of techniques in numerous cell types. The cells of the vascular wall have adapted to specific mechanical stresses through the activation of intracellular signaling pathways which result in cell-specific responses such as hypertrophy, hyperplasia, proliferation, and migration. Vascular smooth muscle of the arteries have been shown to be sensitive to mechanical stimuli such as stretch, and pressure.

This study attempts to add to the current knowledge of mechanotransduction by utilizing the isolated artery preparation. This preparation allows for the study of vascular smooth muscle signal …

The Role Of Glycoconjugates In Mediating Human Fertilization And Induction Of Fetomaternal Tolerance, Manish S. Patankar

Theses and Dissertations in Biomedical Sciences

Using the hemizona assay (HZA), a in vitro sperm-egg binding assay, we show that specific glycoconjugates known to inhibit immune cell interactions mediated by the selectins, potently block human sperm-egg binding. The selectin ligand sialyl Lewis^x inhibits sperm binding in the HZA by 60% at a concentration of 1 mg/ml. Our data indicates that glycodelin-A, a endometrial glycoprotein known to block sperm-egg binding in the HZA at low concentrations expresses unusual fucosylated lacdiNAc type glycans. The fucosylated lacdiNAc type sugars have been previously shown to be 15-20 fold more potent ligands of E-selectin. Glycodelin-S a seminal plasma glycoform of …

Mathematical Models Of Tumors And Their Remote Metastases, Carryn Bellomo

Mathematics & Statistics Theses & Dissertations

Clinical observations and indications in the literature have led us to investigate several models of tumors. For example, it has been shown that a tumor has the ability to send out anti-growth factors, or inhibitors, to keep its remote metastases from growing. Thus, we model the depleting effect of such a growth inhibitor after the removal of the primary tumor (thus removing the source) as a function of time t and distance from the original tumor r.

It has also been shown clinically that oxygen and glucose are nutrients critical to the survival and growth of tumors. Thus, we model …

Reaction-Diffusion Models Of Cancer Dispersion, Kim Yvette Ward

Mathematics & Statistics Theses & Dissertations

The phenomenological modeling of the spatial distribution and temporal evolution of one-dimensional models of cancer dispersion are studied. The models discussed pertain primarily to the transition of a tumor from an initial neoplasm to the dormant avascular state, i.e. just prior to the vascular state, whenever that may occur. Initiating the study is the mathematical analysis of a reaction-diffusion model describing the interaction between cancer cells, normal cells and growth inhibitor. The model leads to several predictions, some of which are supported by experimental data and clinical observations $\lbrack25\rbrack$. We will examine the effects of additional terms on these characteristics. …

Comparison Of Mandibular Surgical Techniques For Accessing Cranial Base Vascular Lesions, Michael A. Devlin

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: Treatment of vascular lesions of the high cervical internal carotid artery (zone III) resulting from penetrating trauma, blunt trauma, aneurysms, and atherosclerosis pose a challenge for vascular surgeons due to bony interference's of the mandibular ramus and mastoid process. Although many techniques have been described, two methods, have been identified as effective and associated with low morbidity. The purpose of this study is to compare these two methods, mandibular distraction and vertical ramus osteotomy, for their effectiveness at increasing access to the cranial base and distal internal carotid artery.

Materials and Methods: Five fresh frozen cadavers were utilized …

Cardiorespiratory Fitness And Cardiovascular Disease Risk Factors In Postmenopausal Women, Bryan L. Haddock

Loma Linda University Electronic Theses, Dissertations & Projects

In spite of the reductions in cardiovascular disease mortality over the last several years, cardiovascular disease remains the number one cause of death in the U.S. Prior to menopause, women have approximately 2.5-4.5 times lower risk of cardiovascular disease than do men of a similar age. Within about 10 years following menopause, however, the rate in women becomes similar to that seen in men. Increased cardiorespiratory fitness and use of hormone replacement have been suggested as ways to improve the cardiovascular disease (CVD) risk profile. Unfortunately, very little is known about the effect of cardiorespiratory fitness on the CVD risk …

Evaluation Of The Role Of Fructosamine As An Indicator Of Diabetic Control, Katherine Hooley

Theses

Diabetes mellitus, a common metabolic disease, is characterised by excess circulating glucose concentrations. Such a hyperglycaemic status provides the stimulus for irreversible glycation (non-enzymatically post-translational) of structural and functional proteins. Protein glycation, although a cause of complication (neuropathy, micro/macrovascular disease), provides a time-averaged index of diabetes status and control. In particular, glycated plasma proteins analysis, i.e., the fructosamine assay, has received favourable response due to its speed, simplicity, low cost, and ease of automation. However, lack of standardisation and a universally-accepted calibrant has limited technical and subsequent clinical confidence in fructosamine analysis. In response, a comprehensive technical evaluation (including novel …

Factors Which Influence Women's Decisions For Choice Of Primary Surgery For Stage I And Stage Ii Breast Cancer, Barbara Mastaglia

Theses : Honours

A descriptive correlational study was conducted to describe the factors that Western Australian women with either Stage I or Stage II Breast Cancer, perceived to be important considerations when deciding upon either Modified Radical Mastectomy (MRM) or Breast Conserving Treatment (BCT) for surgical treatment. The Conflict Theory of Decision Making (Janis & Mann, 1977) was used as the theoretical framework to guide this study. Ward, Heidrich and Wolberg's (1989) Factor List, the Multidimensional Health Locus of Control (MHLC) Scale (Wallston, Wallston & De Vellis, 1978) and a demographic questionnaire were used to measure variables. Questionnaires were mailed to a consecutive …