Life Sciences Commons^™

Conservation Taxonomy Of The Cuban Parrot: Morphological, Plumage And Flight Call Variation, M. Bryant J. Reynolds

Loma Linda University Electronic Theses, Dissertations & Projects

Conservation taxonomy, the study of organismal classification to clarify conservation priorities, seeks to define species and subspecies limits. Allopatric populations, such as those present on islands, pose special challenges to identifying taxonomic boundaries that can be be addressed using diagnostic criteria. Because some of the island populations of Cuban Parrot (Amazona leucocephala) are highly endangered, the five recognized subspecies need careful reevaluation. I measured 18 morphological and plumage characters from 188 museum specimens representing the six extant and one extirpated island populations. I also examined 11 spectrographic characters from the flight calls of 23 parrots representing all six …

Responses To Salinity Of Color Polymorphs In Two Populations Of The Sea Star, Pisaster Achraceus, Viren Johann Perumal

Loma Linda University Electronic Theses, Dissertations & Projects

Pisaster ochraceus was analyzed to determine if varying salinities, animal color, or location affect the physiology of these sea stars. The three responses analyzed were aerobic respiration, ammonia excretion, and self-righting. The tested variables included two different color morphs (orange and purple) of P. ochraceus, two different locations (open coast and inland straits) in Washington State, and three salinities (22, 30, and 40 psu).

Wet mass-specific oxygen consumption rates were not significantly affected by color, location, or salinity, and Dry mass-specific oxygen consumption rates showed no significant differences for main effects, but a three-way interaction was identified. Similarly, ammonia …

An In Vitro Model Of Ovarian Cancer: Studying The Effects Of Talc And Pycnogenol®, Amber Renée Buz'zard

Loma Linda University Electronic Theses, Dissertations & Projects

Ovarian cancer is the sixth most common cancer and accounts for more deaths than any other cancer of the female reproductive system. The American Cancer Society has suggested that poor diet, talc and industrial pollutants may increase the risk of developing ovarian cancer. Talc is ubiquitous and concern is raised about its safety, role as a possible carcinogen and known ability to cause irritation and inflammation. Due to the silent nature of ovarian cancer, chemoprevention is a high priority. The most useful chemopreventive compounds will inhibit, delay or reverse carcinogenesis, and can be taken for long periods of time with …

In Vitro Antimicrobial Efficacy Of Calcium Hydroxides In Root Dentin, Josef W. Lubisich

Loma Linda University Electronic Theses, Dissertations & Projects

Enterococcus faecalis is the most commonly isolated bacteria in failed root canal treatment. Endodontic intracanal medicaments are commonly tested using standardized bovine cylinders infected with bacteria. The literature is not clear on whether calcium hydroxides are able to remove E. faecalis from the dentinal tubules. One reason for this is that there are several varying forms of calcium hydroxide commonly used. The purpose of the present experiment was to determine whether four commonly used calcium hydroxide products were able to reduce E. faecalis from four incremental samples of dentin and to determine if there was a statistically significant difference between …

Synergism Of Gingipains In Endothelial Cell Adhesion Disruption And Apoptosis, Shaun Michellee Sheets

Loma Linda University Electronic Theses, Dissertations & Projects

The presence of Porphyromonas gingivalisin the periodontal pocket and the high levels of gingipain activity detected in gingival crevicular fluid could implicate a role for gingipains in the destruction of the highly vascular periodontal tissue. To explore the effects of these proteases on endothelial cells, we exposed bovine coronary artery endothelial cells (BCAEC) and human microvascular endothelial cells (HMVEC) to gingipain-active extracellular protein preparations and/or purified gingipains from P. gingivalis. Treated cells exhibited a rapid loss of cell adhesion properties that was followed by apoptotic cell death. Cleavage of N- and VE-cadherin and integrin (31 was observed in immunoblots …

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 Acute Effects Of Nut Ingestion On Plasma Levels Of Polyphenol Compounds, Biomarkers Of Antioxidant Status, And Lipid Peroxidation, Setareh Torabian Esfahani

Loma Linda University Electronic Theses, Dissertations & Projects

Nuts are rich sources of polyphenolic compounds and nutrients, which have antioxidant capacity. To assess the acute effect of treatment diet (75% of energy from nuts (walnut or almond) and control diet (habitual diet with no nut consumption) in healthy subjects on plasma total phenol content, antioxidant capacity and plasma lipid peroxidation. Thirteen subjects participated in the crossover design study. After an overnight fast, walnut, almond and a control diet, in form of smoothies, were consumed by the study subjects. Each subject participated on three occasions one week apart, consuming one of the smoothies each time. Blood samples were obtained …

The Environmental Impact Of Dietary Choice And Agriculture In California, Harold J. Marlow Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

Food demand influences agricultural production. Modern agricultural practices have resulted in polluted soil, air and water, eroded soil, dependence on imported oil, and loss of biodiversity. The goal of this research is to investigate the environmental impact of pesticide and fertilizer application, water consumption, and energy used to produce commodities for a vegetarian and non vegetarian diet in California. The working assumption is that greater number and amount of inputs are associated with greater environmental impact. The literature supports this notion. To accomplish this goal, dietary preferences were quantified using the Adventist Health Study and state agricultural data were collected …

The Effect Of Calcium Hydroxide Pastes On Root Dentin Fracture Resistance, Kurt W. Sturz

Loma Linda University Electronic Theses, Dissertations & Projects

Calcium hydroxide is a common intracanal medicament used in the treatment of immature teeth that have been subjected to trauma or decay prior to root canal therapy. The effect of calcium hydroxide on immature root dentin is important. One area of concern is the effect that calcium hydroxide has on the fracture resistance of an immature tooth. It is the aim of this study to compare the effect of four different commercially available calcium hydroxide pastes on the fracture resistance of bovine teeth. Seventy-five freshly extracted, intact bovine incisors were prepared according to a modified Haapasalo and Orstavik technique. Each …

The Relationship Between High Sensitivity C-Reactive Protein, Metabolic Syndrome And Exercise, Micheline A. Vargas

Loma Linda University Electronic Theses, Dissertations & Projects

Background: It is well known that regular physical activity is associated with lower risk of chronic diseases such as diabetes and cardiovascular disease. Physical activity is also considered an important determinant of metabolic syndrome. All levels of metabolic syndrome, diabetes, and cardiovascular disease are thought to involve inflammation. Physical activity may reduce risk, at least in part, by modifying the inflammatory process. Recent studies have demonstrated an inverse relationship between inflammatory markers, such as high sensitivity C-reactive protein (hs-CRP), and physical activity. Elevated hs-CRP appears to be an independent predictor of both CVD and diabetes. Recent evidence also suggests that …

Effects Of Diabetes Mellitus On The Healing Of The Dental Pulp, Stuart Evan Garber

Loma Linda University Electronic Theses, Dissertations & Projects

Diabetes Mellitus (DM) has been implicated as a factor affecting healing. The purpose of this study was to use the healing of experimentally exposed pulps subsequent to pulp capping as a model to determine the effect of DM on healing.

Twenty-two Sprague-Dawley rats were divided into two groups of eleven animals each. In one group, DM was induced by injection of 70 mg/KG of streptozotocin. In the other group, the animals were injected with sterile saline. Under anesthesia with Ketamine and Xylazine, the pulps of the maxillary first molars of all rats were exposed using a 1/16 round bur under …

Factors That Influence The Blood Flow Response Of Skin To Electrical Stimulation, Abdul-Majeed Raja Al-Malty

Loma Linda University Electronic Theses, Dissertations & Projects

Female reproductive hormones, aging, global heating and local heating are factors affecting skin blood flow (SBF), but their effect on electrical stimulation (ES) has never been examined until the present investigation. To investigate female reproductive hormones, nine women (age= 25.6±3.5 years) with a normal menstrual cycle (MC) underwent ES in thermoneutral (25°±0.5°C) and warm environments (35°±0.5°C). To investigate aging, ES was applied on active young (n=15, age=32.1±8.3 years) and old (n=8, 64.5±6.2 years) groups in thermoneutral and warm environments. To investigate the effect of global and local heating, groups of 15 and 18 subjects (age= 18-40 years) experienced ES under …

Effects Of Advancing Age On Er Calcium Regulation In Rat Superior Cervical Ganglia, Conwin Kodel Vanterpool

Loma Linda University Electronic Theses, Dissertations & Projects

Intracellular calcium ([Ca²⁺]i) release from endoplasmic reticulum (ER) stores plays an important role in cell signaling. These stores are rapidly refilled via voltage-gated calcium channels or spontaneously via store-operated calcium channels and subsequent pumping by ER Ca²⁺-ATPases. Calcium release is triggered by the activation of the ryanodine receptor (RyR) channels and their function is in part dependent on their expression. We analyzed the [Ca²⁺]i transients in fura 2-loaded superior cervical ganglion (SCG) cells from 6, 12, 20, and 24-month-old Fischer 344 rats for their ability to rapidly and spontaneously refill. For rapid refilling, the …

Membrane Organization And Multimeric Interactions Of The Aer Receptor In E. Coli, Divya Dashrathkumar Amin

Loma Linda University Electronic Theses, Dissertations & Projects

Escherichia coli swims toward niches ideal for generating maximum energy by monitoring the environment with the aerotaxis sensor, Aer. This receptor has an N-terminal PAS domain, which is a sensor module present in a variety of proteins from all kingdoms of life (including humans). To date, the mechanism of signaling from a PAS sensor domain to a single signaling receiver domain has not been resolved. In Aer, the PAS sensor is separated from the signaling region by a membrane anchor. Most "transmembrane prediction" programs forecast a single membrane span for this membrane anchor, but such a topology is inconsistent our …

Influence Of Human Papillomavirus 16 E6 On Trail-Mediated Apoptosis, Theodore O. Garnett

Loma Linda University Electronic Theses, Dissertations & Projects

Viruses have developed sophisticated strategies to evade host defenses and facilitate the production and spread of progeny. HPV 16, whose immune evasion activities can contribute to cervical cancer, is a prime example of such a virus. In this study, we examined the influence of HPV 16 E6 on TRAIL-induced FADD-dependent and -independent pathways in two cellular models: HCT116 colon carcinoma cells and U2OS osteosarcoma cells. We show that transfection of the HPV 16 E6 oncogene into HCT116 cells provides protection from TRAIL-mediated apoptosis. Additionally, we demonstrate that the protection provided by E6 is dose-dependent because higher levels of E6 provide …

Systematics Of The Endangered Mauremys Mutica And Mauremys Annamensis, Jonathan Julio Fong

Loma Linda University Electronic Theses, Dissertations & Projects

Almost all turtle species in Asia are going extinct due to the demand for turtle products as food and medicine. A difficulty in creating effective conservation measures is that very little is known about the evolutionary relationships between populations and species. It is believed that several lineages we are currently calling species could in actuality be a complex of several species. One of these supposed species is the Yellow Pond Turtle, Mauremys mutica. Previous research has shown this group to have a tremendous amount of morphological and molecular diversity. In this study, I have used a combination of known-locality, farm, …

Comparison Of The Barnacle, Balanus Amphitrite, In Different Environments, Katsura Mastuda

Loma Linda University Electronic Theses, Dissertations & Projects

The Salton Sea is a saline lake located centrally in the Colorado Desert, California. Salinity as well as nutrients of the Sea have been increasing since 1907, thus it is currently facing ecological collapse. The barnacle, Balanus amphitrite saltonensis at the Salton Sea was once thought to be a subspecies of B. amphitrite due to distinctive morphological differences between populations at the Sea and San Diego Bay. However, only one subspecies, Balanus amphitrite amphitrite, currently exists based on genetic studies. My study investigates physiological, survival, and morphological differences of B. amphitrite populations from the Salton Sea and San Diego …

Mineralized Bone Allograft In Maxillary Sinuses Histology And Histomorphometry, Sammy Stefan Noumbissi

Loma Linda University Electronic Theses, Dissertations & Projects

Background: Demineralized freeze-dried bone allografts (DFDBA) and deproteinized bovine bone xenografts (DMBBX) have been used for sinus augmentation for many years with varying results, but very little has been reported on the clinical efficacy or the histological analysis of mineralized solvent dehydrated bone allografts (MSDBA) as sinus graft materials. This study histologically and histomorphometrically evaluated an MSDBA material called PUROS to augment atrophic human maxillary sinuses.

Materials & Methods: Seven partially and completely edentulous patients requiring unilateral (n=4) or bilateral (n=3) sinus grafts prior to implant placement were selected for this study. Test grafts consisted of MSDBA, and control …