Life Sciences Commons^™

The Role Of Brn-3.2 In Retinal Ganglion Cell Differentiation, Jerin Marie Wright

Loma Linda University Electronic Theses, Dissertations & Projects

Within the retina, the POU domain of transcription factors brn-3.0, brn-3.1, and brn-3.2 are present only in retinal ganglion cells. These genes are believed to be involved in establishing neural cell lineages in mammals. In this study brn-3.2 was examined by comparing the number of ganglion cells present during postnatal development in normal mice (+/+), in mice homozygous (-/-) for the brn-3.2 gene, and in adult mice with a heterozygous gene deletion (+/-) for brn-3.2. Optic nerve cross sections were imaged by electron microscopy, and axon profiles counted systematically by hand. These counts were then related to the nerve cross …

Abnormal Electrical Potentials In Lower Limb Muscles After Ankle Sprain Grades I, Ii And Iii, Talal A. Al-Shatti

Rehabilitation Sciences Theses & Dissertations

Fibrillation and positive sharp wave potentials have been found after ankle sprain in muscles around the injured joint. The purpose of this study was to better define and explain the reaction of the muscles around the ankle joint after grades I, II and m ankle sprains. Methods: Fifteen subjects (9 males and 6 females, mean age of 33.2 years) with ankle sprains voluntarily participated in this study. A stress x-ray was done to determine the grade of ankle sprain. Nerve conduction velocity and EMO studies were done three weeks after the injury. None of the patients in this study manifested …

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 …

Neuronal And Metabolic Increases In Pedunculopontine Nucleus Of Parkinson's Rats, Jonathan Dennis Carlson

Loma Linda University Electronic Theses, Dissertations & Projects

The theoretical mechanisms underlying the symptoms of Parkinson’s disease are based on dysfunctional output from the basal ganglia projected to the cortex via the thalamus. However, the subthalamic nucleus (STN) and substantia nigra pars reticularis (SNr) as part of the basal ganglia, also project to the brainstem, in particular to the pedunculopontine nucleus (PPN). Both the STN and SNr have altered neuronal activity in the 6-hydroxydopamine (6-OHDA) Parkinson’s model rat. Thus, it is hypothesized that the PPN is altered in this model of Parkinson’s disease.

This hypothesis was examined by comparing the rates of glucose metabolism and spontaneous neuronal activity …

The Immunology Of Parturition, Ari Mayer Mackler

Loma Linda University Electronic Theses, Dissertations & Projects

Macrophage-derived factors have been implicated in the etiology of preterm labor but little is known about trafficking of this immune cell into the uterus or its regulation of uterine contractility in mice. Enhanced number and activation of macrophages was hypothesized to precede parturition. Studies characterized contractile activity and the distribution of macrophages in the uterus of C3/HeN mice before and after term (=day 19). Contractile activity by uterine strips on days 15 and 18 of pregnancy, the day of delivery, and 1 day postpartum indicate that an endogenous oscillator sustains high frequency contractions. Modest acceleration of the pacemaker occurred before …

Effects Of Long-Term, High-Altitude Hypoxemia On Fetal Ovine Coronary Arteries, Felizabel C. Garcia

Loma Linda University Electronic Theses, Dissertations & Projects

To our knowledge, this is the first series of in vitro studies to investigate the effects of long-term, high-altitude hypoxemia on the contractility of fetal coronary vessels, namely the left circumflex, left anterior descending, and right coronary arteries. We have found that in response to chronic hypoxia, isolated fetal ovine coronary arteries exhibit attenuated contractile responsiveness to potassium and the thromboxane A2 mimetic. U46619. Furthermore, long-term, high-altitude hypoxia produced no significant alteration in the maximum relaxation response and sensitivity to adenosine in all vessel groups examined. We also addressed the possible role of nitric oxide (NO) in the pharmacological responsiveness …

Maternal Modulation Of Neonatal Immunity, Omar R. Fagoaga

Loma Linda University Electronic Theses, Dissertations & Projects

Although the neonatal immune system is functionally immature, immune response capabilities are not the same in all newborns. The objective of this thesis was to determine development of immunocompetence and test the hypothesis that activation of maternal inflammatory immunity during pregnancy influences maturation of the neonatal immune system.

Lymphocytes in blood and spleen were immunophenotyped by flow cytometric analysis to determine differentiation characteristics, and splenocytes were assessed for cytokine production capabilities. In normal Th2-prone outbred (CD-1) mice, an adult repertoire of naïve lymphocytes has developed by day 10 and memory cells by day 20, in blood and spleen. However, in …

The Acquisition And Quantitative Analysis Of Digitally Generated Fourier Transforms Resulting From The Physiognomy Of Various Tree And Shrub Species, Alicia Eldridge-Spears

Theses, Dissertations and Capstones

An optical Fourier transform represents the interference of wavefronts produced as light passes through multiple slits. Theoretically, any image containing periodic structure causes diffraction. The cellular arrangement of a plant leaf and the regularity in venation are ideal conditions for diffracting light. As light passes through columns of cells, its path is altered according to the distance and orientation present.

A photograph or slide of a leaf or the leaf itself may be used to produce a diffraction pattern by either optical or digital means. Optically, a laser beam directed through a slide is refracted by a converging lens and …

Correlation Of Visualized Glucocorticoid Receptor And Apoptosis In Individual Clones Of Nb2 Cells, Devang M. Patel

Theses and Dissertations

The Nb2 lymphoma cell line is susceptible to glucocorticoid (GC)-induced apoptosis in the absence of mitogen and this effect is inhibited by the mitogen prolactin (PRL). This process is believed to be mediated by the glucocorticoid receptor (GR) and various downstream signals. The purpose of this study was to use the limiting dilution method to isolate subsets of Nb2 clones which expressed either highly enriched amounts of GR or an absence of GR and to relate the amount of GR to the magnitude of GC induced cytolysis. The presence of GR in these clones was determined by immunocytochemistry (ICC) using …

The Effects Of Moulting On Muscle Fibre Characteristics Of The Yabby, Cherax Albidus, Tina Marie Lamey

Theses : Honours

In order to grow, crustaceans must shed their exoskeleton in a process known as "moulting'. Although this process is short and intermittent, it remains dominant over the life of a crustacean. Physiological changes in the period between moults (intermoult) are comparatively quiescent as opposed to the periods directly before and after the actual moult, known as premoult, and postmoult respectively (West, 1997). Moulting is associated with distinct physiological changes including the breakdown of muscle (Musgrove and Geddes, 1985). This muscle breakdown, known as atrophy is the diminution in size of the actual muscle mass and is very specific, occurring to …

A Comparison Of Nutritional Knowledge, Eating Attitudes, Training Regimens, And Body Composition Between Normal And Abnormal Menstruating Female Adolescent Cross Country Athletes, Dena Maureen Block

Masters Theses

The purpose of this study was to compare factors that may influence menstrual irregularities of female adolescent high school cross-country runners, ranging from 13-18 years of age. A survey was utilized to determine the subjects age, year in school, exercise history, menstrual history, and training regimens and where the subjects sought nutritional information. The groups were separated according to their current menstrual status. One group (normal) consisted of subjects who currently had a normal menstrual cycle for at least one year (n=17), while the other group (abnormal) (n=18) experienced an irregular menstrual cycle.

A twenty item questionnaire was administered to …

Circadian Rhythms And Melatonin Receptors As Sources Of Individual Variation In Reproductive Photoresponsiveness, Sean Bradford Majoy

Dissertations, Theses, and Masters Projects

No abstract provided.

Examination Of Signals Involved In Dexamethasone Induced Apoptosis In Nb2 Lymphoma Cells, Suhas Badarinath

Theses and Dissertations

Consistent with previous studies, we demonstrated that dexamethasone (Dex) caused cytolysis/apoptosis in log phase Nb2 lymphoma cells, while prolactin (Prl) inhibited this effect. The Nb2 model was used to investigate the mechanisms of apoptosis control with the aid of immunocytochemistry (ICC). We established with absorption the specificity of staining due to Fas, Fas Ligand, Bcl-2, and Bax antibodies (the specificity of anti-p53 could not be verified). Dex-induced cytolysis/apoptosis was detected in synchronized (G⁰/G¹) cells after 6 and 8 hours of Dex exposure. A novel, computerized technique was used to quantitate the proportion of cells immunostained for the signals of interest …