Digital Commons Network^™

Effect Of Dietary Factors On Mutagenesis, Metabolism, And Binding To Dna Of Benzo [A] Pyrene And Benzo [A] Pyrene 7, 8-Dihydrodiol, Robin E. Vance

Loma Linda University Electronic Theses, Dissertations & Projects

Ellagic acid (EA), a naturally occurring plant phenol, at concentrations of 5 to 50 pg/plate, inhibited rat liver S9 protein dependent benzo[a]pyrene (B[a]P)-induced mutagenesis in Salmonella typhimurium TA 100 by 30-81% and B[a]P 7,8-dihydrodiol (DHD)-induced mutagenesis by 29 to 75%. EA (5-40 juM) did not significantly affect the metabolism of B[a]P or B[a]P 7,8-DHD as determined by high performance liquid chromatographic analysis of the organosoluble fraction and by the quantification of watersoluble conjugates. At these concentrations EA inhibited 3 3 the covalent binding of [ H] B[a]P and [ H] B[a]P 7,8-DHD metabolites to calf thymus DNA by 5 to …

The Prenatal Development Of The "Synaptic" Structures In The Guinea Pig Pineal Gland, Zhongrong Luo

Loma Linda University Electronic Theses, Dissertations & Projects

Pineal "synaptic" ribbons are a heterogeneous population of organelles. In addition to "synaptic" ribbons (SR) sensu stricto, which are electron-dense rods, "synaptic" spherules (SS) and intermediate forms (IMF) are present. The SS are electron-dense spherical structures, the diameter of which is two to three times the width of the SR. The IMF appear as irregularly formed structures. The SR, SS and IMF are surrounded by electron-lucent vesicles. Their function and origin are unknown and also a knowledge of their prenatal development is lacking. In order to gain an insight into the development of the "synaptic structures, the pineal glands …

Dietary And Hormonal Evaluation Of Men At Risk For Prostate Cancer, Donald J. Pusateri

Loma Linda University Electronic Theses, Dissertations & Projects

Relationships between dietary nutrients and plasma and fecal estrone, estradiol-17β, testosterone, and plasma prolactin levels were studied in young Seventh-day Adventist men: 18 nonvegetarians (NV), 20 lacto-ovovegetarians (LOV), and 15 vegans (V). Blood samples and 3 d dietary records were obtained. Contemporaneously collected diet composites and stool samples were analyzed for fiber. The vegetarians consumed significantly more fiber than the omnivores, while NVs and LOVs consumed more saturated fat than the Vs. Although plasma steroid hormone status did not differ, the Vs had significantly higher fecal estrogen levels than the NVs or LOVs. Plasma prolactin levels were significantly higher in …

Nutrient Intake Of Marathon Runners, Janice V. Butler

Loma Linda University Electronic Theses, Dissertations & Projects

Three-day food records from a large group of marathon runners were analyzed and compared to various standards of dietary quality. Nutrient intake by the runners exceeded two-thirds the Recommended Dietary Allowance for all nutrients except for vitamin D and zinc in female runners. Energy and nutrient intake levels in the marathon runners were higher than those of the general US population except for fat and zinc in both males and females, and vitamin B12 in females. In general this group of runners consumed diets that would be considered more optimal than those of the general population. However, both caloric intake …

Genetic Transformation In Salmonella Typhimurium, Siao Ping Tasi

Loma Linda University Electronic Theses, Dissertations & Projects

Plasmid transformation is an essential step in many gene cloning experiments. In Salmonella tynhimurium, mutants of rough strain have shown improved transformation frequency previously. In this work a stable restriction-minus (r^-) and modification-plus (m⁺) strain and its derivatives were constructed. Effect of restriction barrier on transformation of plasmid pBR322 was tested. Several factors which may affect transformation frequency have been systematically examined to determine the optimum conditions for transformation in S. tvphimurium. Efforts were made to simplify the procedure.

Using pBR322 plasmid as an experimental model, the r^- strain demonstrated 10⁵ to …

The Inhibition Of Bone Formation Occurring Under Weightlessness : The Effect Of Skeletal Unloading On Serum Levels Of A Bone-Derived Growth Factor, Jean D. Sibonga

Loma Linda University Electronic Theses, Dissertations & Projects

A deleterious effect of spaceflight on human health is the loss of bone associated with the prolonged lack of gravitational stress on the skeleton. A potential for bone loss is indicated by the hypercalciuria and decreased heel bone density determined in Skylab astronauts. Histological studies of juvenile laboratory rats in actual spaceflight and in simulation models document a suppression of bone formation with little alteration of bone resorption. The mechanism for net bone loss needs to be defined in order to develop measures for its prevention or correction.

Skeletal growth factors, which may mediate coupling and locally regulate bone volume …

Age-Related Changes In Meissner Corpuscles Of Diabetic Mice As Observed By Electron Microscopy, Vicky R. Ras

Loma Linda University Electronic Theses, Dissertations & Projects

Light touch and low-frequency vibration sense are often impaired in diabetic patients. Meissner corpuscles are distally located mechanoreceptors that respond to these stimuli. Peripheral sensory neuropathy in diabetes progresses from distal to proximal, therefore, Meissner corpuscles are ideally suited to study diabetic neuropathy in the C57BL/Ks (db/db) mouse.

Corpuscles from the forepaw digital pads of 9 diabetic and 9 nondiabetic littermates were studied by electron microscopy. These were divided into 3 age groups; 2.5 months, 10 months, and 17 months old.

Ultrastructural changes observed within various receptor components were myelin figures, multivesicular bodies, vacuoles, basal lamina duplication, abnormal and enlarged …

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 …

A [6-14c] Glucose Autoradiographic Study Of The Rat Brainstem Under Hypercapnic And Hypocapnic Conditions: Identification Of Respiratory-Related Regions, Tobey M. Leung

Loma Linda University Electronic Theses, Dissertations & Projects

The effects of systemic hypercapnia on brainstem metabolism were studied with the [6-¹⁴C] glucose autoradiography method. Neuronal pools which are metabolically active take up more [6-¹⁴C] glucose and maybe revealed pictorially as darker areas on autoradiograms. Since a high concentration of carbon dioxide stimulates central chemoreceptors and hence enhances respiratory drive, the darker regions on the autoradiograms may represent regions concentrated with respiratory-related neurons. Two discrete regions in the ventrolateral medulla (a column near nucleus ambiguus and a column in the lateral reticular nucleus) appeared dark and were analyzed with an image processing system, which converted …

Comparison Of Five Different Serological Assays For Determination Of Antibody Levels Against Herpes Virus Type 1 And 2, Murat Sami Küçük

Loma Linda University Electronic Theses, Dissertations & Projects

To aid in the diagnosis of certain clinical types of Herpes virus infections, we evaluated and compared five serological methods for measuring Herpes virus antibody. The five tests we compared are complement fixation test (CF), indirect immunofluorescent antibody assay (IFA), anticomplementary immunofluorescent assay (ACIF), enzyme linked immunoassay test (ELISA), and the latex agglutination test (LA). The main objective of this study was to establish which of the currently available serologic tests was best suited for clinical laboratory use and which may then replace the complement fixation test. In the comparative testing, one hundred twenty serum samples were divided into four …

A Descriptive Catalog Of Dimming Cells In The Purple Shore Crab Hemigrapsus Nudus, Eugene Pak

Loma Linda University Electronic Theses, Dissertations & Projects

A population of cells responsive to the decrease or dimming of light was identified in the Purple shore crab Hemigrapsus nudus. Extracellular pin electrode recordings from the optic nerve tract measured responses to decremental changes in relative light levels over the range 40 to 0.08 lux. The observed activity revealed that these dimming cells could respond over this entire range. A catalog detailing the response characteristics for each of the thirty dimming cells in the study was generated. The parameters measured the receptive field size; response to mechanoreceptive tactile stimuli; response to abrupt On or Off light level changes; …

Chemoreceptors Regulate Discharge Of Microbasic P-Mastigophores In The Sea Anemone, Aiptasia Pallida, Gail E. Muir Giebel

Loma Linda University Electronic Theses, Dissertations & Projects

Recently, using cnida-mediated measurements of adhesive force, Thorington and Hessinger (1984, 1988a, b) identified two different chemoreceptors involved in triggering cnida discharge on the tentacles of the sea anemone, Aiptasia pallida. These two classes of receptors were shown to interact with glycine and N-acetylneuraminic acid (NANA). We now show that the discharge of the microbasic p-mastigophores, one of the three types of cnidae present on the tentacles of A. pallida, is under the controlling influence of these two classes of cnidocyte-associated chemoreceptors. We also demonstrate that the number of discharged microbasic p-mastigophores adhering to the test probes is proportional to …

Effects Of Corticosteroids And Of Cyclosporin A On Trypanosoma Musculi In Mice And In Culture, Philip Stephen Schuyler

Loma Linda University Electronic Theses, Dissertations & Projects

The in vivo and in vitro effects of cyclosporin A and corticosteroids on Trypanosoma musculi were examined. Mice that received continuous administration of 6 mg/liter/day of dexamethasone in drinking water and 200 mg/kg hydrocortisone acetate as a single dose 24 hrs prior to injection with T. musculi had significantly higher and longer parasitemias, than controls. Body and spleen weights and B cell responsiveness were lower in test animals and there were some deaths. Mice injected with T. musculi that received 100 mg/kg/day cyclosporin A had longer, but not higher, parasitemias than controls. Corticosteroids appear to partially inactive antibody production (i.e. …

Determination Of Antibody Levels In Periapical Lesions Against Sixteen Oral Microorganisms By The Elisa Technique, Sammee Lee Jones

Loma Linda University Electronic Theses, Dissertations & Projects

The root canal system, which includes the periapical region of the tooth, may become infected by several types of microorganisms which are normally associated with these tissues. A bacteria-specific antibody response may occur at the local level, where various classes of immunoglobulins have been found and reported in the literature. The purpose of this study was to quantitatively measure locally produced immunoglobulin' levels in periapical lesion abscess materials and to determine the specific reactivity of these antibodies to several microorganisms which are normal flora, as well as being previously associated with the development and pathogenesis of endodontic infections. Periapical lesions …

Decreased Triiodothyronine Binding To The Hepatic Nuclear Thyroid Hormone Receptor In The Diabetic Mouse, Thomas J. Dewind

Loma Linda University Electronic Theses, Dissertations & Projects

The diabetic C57BL/KsJ-db m mouse has abnormal thyroid hormone levels and indications of thyroid hormone resistance. To investigate the basis of these abnormalities, the hepatic nuclear thyroid hormone receptor was extracted with 0.4 M KCl, 1.1 mM MgCl₂, 20 mM Tris/HCl, pH 7.9 from hepatocyte nuclei of normal C57BL/KsJ, heterozygous C57BL/KsJ-db m (db/m), and diabetic C57BL/KsJ-db m (db/db) mice. Normal and heterozygous mice were grouped together as the controls. Triiodothyronine (T₃) binding studies at 4°C using nitrocellulose filtration to separate free T₃ from receptor bound T₃ demonstrated an …

The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton

Loma Linda University Electronic Theses, Dissertations & Projects

Theories regarding the taphonomy of fishes in lacustrine environments have traditionally relied on an anoxic water column to explain the excellent preservation. This concept has never been directly tested in modern lacustrine environments that are thought to be analogous to the lacustrine environments predicted by the Stratified-lake Model. This research tested that model by searching for fish remains in 38 collected bottom samples of six modern lacustrine analogues, including Fayetteville Green Lake, New York. The bottom sediments of a warm, holomictic, shallow, and saline lake (Salton Sea, California) were also examined. Although laminated sediments were found in all of the …

Immunologic Mechanisms Involved With Human Endodontic Lesions, Sunita V. Prabhu

Loma Linda University Electronic Theses, Dissertations & Projects

Endodontic or root canal infection results in immunologic changes in periapical region, which causes the destruction of pulpal and periapical tissue. No definitive study has identified a specific organism or a group of organisms as a etiological agents. Past studies have indicated that immunoglobulin E play a significant role in the pathogenesis of periapical lesions. The presence of this factor suggests that some of the endodontic flare-ups may be IgE-mediated hypersensitivity reactions. Antibody levels of IgA have been quantitatively measured by ELISA and IgE by modified RAST assay, against eleven oral bacteria which are routinely isolated from such lesions. The …

The Effect Of 48 Hr Glucose Administration On The Hepatic P-450 System, John N. Buchholz

Loma Linda University Electronic Theses, Dissertations & Projects

The administration of glucose for 48 hrs to mice resulted in a shift of the dose response curve of phenobarbital, an indication that glucose administration significantly sensitized the animals to the effects of the drug. Glucose administration produced a reduction in the catalytic activity of hepatic microscopical P-450 as measured by the in vitro conversion of p-Nitrocellulose to p-Nitrophenol.

The administration of glucose to rats for 48 hrs resulted in prolonged anesthesia after the administration of pentobarbital. The spectral binding of hexobarbital and methadone to hepatic microsomal P-450 was found to be significantly reduced following glucose administration. The changes in …

The Isolation And Characterization Of Growth Regulatory Factors Produced By A Herpes Simplex Virus Type 2 Transformed Mouse Tumor Cell Line, H238, Robert B. Stagg

Loma Linda University Electronic Theses, Dissertations & Projects

Transformation of cells with herpes simplex virus Type 2 (HSV- 2)occurs by an unknown mechanism. No specific gene or gene product has been consistently associated with HSV-2 transformation as is the case for other tumor viruses. This study was performed in an attempt to associate HSV-2-transformation with specific growth factors in order to develop a testable model for HSV-2-transformation. For some tumor viruses, particularly those containing RNA, there has been a central concept (autocrine secretion) linking oncogenes and growth factors. This concept centers on the ability of the cancer cells to produce and respond to their own autologous factors. We …

Electromagnetic Field Variations In The Activation Of Bone Cell Synthesis, Gary Ketcherside

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Dosage Window Of Selenium On Human Natural Killer Cytotoxicity And Neutrophilmediated Chemiluminescence, Mary Labue

Loma Linda University Electronic Theses, Dissertations & Projects

Few studies have been conducted on the effect of in vitro selenium (Se) supplementation on cellular immunity. In the present study, the effects of in vitro incubation with sodium selenite on natural killer (NK)-mediated cytotoxicity and phagocyte chemiluminescence (CL) were examined. NK-mediated cytotoxicity and phagocyte CL were observed to be affected by added selenite. These changes generally included augmentation and suppression of both neutrophil CL and NK-mediated cytotoxicity. All dosages of selenite used were shown to be capable of causing augmentation of neutrophil CL. However, 1.0 /xg/ml selenite was also observed to occasionally cause depression of neutrophil CL. When Se …