Medicine and Health Sciences Commons^™

Assessment Of Immune System Involvement In Tourette Syndrome, Ashley Dawn Levine

Loma Linda University Electronic Theses, Dissertations & Projects

Tourette syndrome (TS) is currently hypothesized to be the result of genetic and immunological components. This study investigated whether TS subjects produce IgG and IgA antibodies that bind to caudate nucleus, hippocampus, frontal cortex, cerebellum, thalamus, globus pallidus interior, exterior and putamen. Thirty- two children (14 TS, 7 family control, and 11 non-family control) and thirty-nine adults (11 TS, 14 family control, and 14 non-family control) were studied. Immunofluorescent studies were performed on basal ganglia tissue using serum from TS children and their family members. Brain antigens were prepared as two fractions (supernatant and pellet) and used as targets for …

In Vitro And In Vivo Studies On Bone Formation, Charmaine Richman

Loma Linda University Electronic Theses, Dissertations & Projects

The research focus of this dissertation deals with two major issues relevant to osteoporosis, the most common metabolic bone disease. These two aspects are: 1) mechanisms that are involved in the regulation of peak bone density, and 2) evaluation of the in vivo effects of Insulin-like Growth Factor Binding Protein-5 (IGFBP-5) as a potential means to treat osteoporosis.

The first study compared two strains of inbred mice, one with high bone density and one with low bone density, to determine when and to what extent bone density accumulation during postnatal and pubertal growth contributed to the observed differences in bone …

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 …

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 …

Diagnosis And Treatment Of Swallowing Dysfunctions : Semg Cognitive Training As An Adjunct To Conventional Therapy, Vicky T. Nguyen

Loma Linda University Electronic Theses, Dissertations & Projects

This study compared surface electromyography (sEMG) cognitive training to conventional myofunctional therapy in controlling a swallowing dysfunction, commonly referred to as "tongue thrust". Nasal airway resistance (NAR) was assessed on every subject, to rule out mechanical obstruction that would prevent proper function. The scope of this investigation composed of evaluating baseline activity and dry swallowing patterns. Subjects were distributed to one of three treatment groups: sEMG cognitive training, conventional myofunctional therapy, and control, based on the degree of NAR (normal, mild, or moderate). Initial sEMG recordings were then taken on subjects that clinically demonstrated a tongue thrust habit to confirm …

Regulation Of Connexin43 By Phosphorylation In Heart Development, John C. Duncan

Loma Linda University Electronic Theses, Dissertations & Projects

Serine/threonine protein kinases have been shown to reversibly regulate cell-cell communication through gap junctions formed by connexin 43 (Cx43) (Godwin et al.7 1993). The Cx43 protein expression levels are unclear and what role phosphorylation plays in the regulation of signal transduction through these gap junctions during heart formation. Reportedly, mutations which replace potentially phosphorylatable serines within the Cx43 protein are associated with heart malformations (Britz-Cunningham et al.. 1995), highlighting the importance of determining the levels of Cx43 and the activities of PKA and PKC during heart development.

Western analysis performed on hearts from developmentally significant time points revealed principally high …

Localization Of Sodium, Potassium-Adenosine Triphosphatase In The Cerebral Cortex Of Developing Rats, Maki Ujiie

Loma Linda University Electronic Theses, Dissertations & Projects

Active transport via Na⁺, K⁺-ATPase plays an important role in establishing and maintaining proper ionic gradient across all mammalian cell membranes. A strict regulation of Na⁺, and K⁺ ion levels is especially important in excitable cells such as neurons and myocytes. Inhibition of the enzyme is associated with several pathological conditions and has serious detrimental effects on cerebral cortical cells. Yet the enzyme appears to be limited in amount and distribution in newborn rats. In this study, Na_⁺, K⁺- ATPase expression and distribution in early postnatal rats were studied …

A Cytochemical Evaluation Of Blood-Brain Barrier Sodium, Potassium- And Calcium-Adenosine Triphosphatase Polarity, Panya Steve Manoonkitiwongsa

Loma Linda University Electronic Theses, Dissertations & Projects

The blood-brain barrier (BBB) is formed by cerebral vascular endothelial cells. Brain ion and fluid homeotasis essential for proper neural functioning is due to the BBB. Sodium-potassium and calcium-activated adenosine triphosphatase (Na⁺, K⁺-ATPase and Ca²⁺-ATPase) serve as one of the main mechanisms controlling brain Na⁺, K⁺, and Ca²⁺ concentrations. The present accepted concept is that both of these enzymes are localized to the abluminal plasma membrane of endothelial cells although there have been contrary results from some studies. Because of these discrepancies, further work was needed. Various cytochemical procedures …

Reference Serum Chemistry And Hematological Values For Spinal Cord Injured Patients, Michael S. Laymon, Antone L. Davis Ii

Loma Linda University Electronic Theses, Dissertations & Projects

Serum chemistry and hematological values from 220 traumatic spinal cord injured patients (157 male and 63 female between the ages of 15-47, with greater than six months from injury) were compiled via chart review. Traumatic spinal cord injured patient’s reference ranges were determined and compared with the general population reference ranges. Reference ranges within the spinal cord population were compared by age, gender, level of injury and chronicity of injury. The reference ranges determined for all groups within this spinal cord population fall within the reference ranges of the general population. This supports recent research which suggests that a decrease …

Evaluation Of Nitric Oxide In Respiratory Distress Syndrome, Kimberly S. Myruski

Loma Linda University Electronic Theses, Dissertations & Projects

Little is known of the effects of low concentrations of inhaled nitric oxide (NO) on pulmonary mechanics and lung volumes in premature newborn infants with lung disease. Cardiopulmonary function tests including blood gas analyses were obtained from eleven premature lamb models with respiratory distress syndrome to determine if compliance, airways resistance, tidal volume, functional residual capacity, and gas exchange were affected. The effect of inhaled NO on the direction of shunting through the ductus arteriosus was determined using echocardiography.

Twin lambs were cannulated with arterial and venous catheters and intubated with an endotracheal tube before delivery on gestational day 126-130 …

Regulation Of The Insulin-Like Growth Factor System By Retinoic Acid In Human Osteoblast Cells, Yuehua Zhou

Loma Linda University Electronic Theses, Dissertations & Projects

Retinoic acid (RA) is an important regulator of growth and differentiation in many cell types, including bone. However, its effects on human osteoblast cell growth and differentiation have not been well studied. Therefore, I investigated the effect of RA on proliferation and differentiation of normal human bone cells (HBCs) and human osteosarcoma, SaOS-2 cells. RA decreased baseline as well as serum-stimulated proliferation in normal HBCs. To determine the effect of RA on differentiation, expression of several osteoblastic differentiation markers were studied. RA decreased type I procollagen mRNA levels and l,25(OH)₂D₃-stimulated osteocalcin and alkaline phosphatase (ALP) mRNA …

Stab Wounds To Rat Brains : Demyelination, Remyelination And The Cellular Response, Particularly Of Oligodendrocytes, Xie Dangci

Loma Linda University Electronic Theses, Dissertations & Projects

The present body of knowledge concerning the results of central nervous system injury is incomplete and controversial. The role of oligodendrocytes, the cells involved in phagocytosis, the stages of demyelination, and the evidence for remyelination are of interest. Following stab wounds to rat brain cortex, corpus callosum and hippocampus, the animals were examined at 4,7,11,18,23,29,45,60 and 70 days postoperation (dpo). To help in the identification of cells immunocytochemical markers for astrocytes and immature oligodendrocytes were used. These were labels for glial fibrillary acidic protein (GFAP) and myelin/oligodendrocyte specific protein (MOSP) respectively. Light and electron microscopy were correlated using conventionally prepared …

Short And Long Term Effects Of Proton Microbeam Irradiation : In The Lateral Geniculate Nucleus Of Felis Domesticus, Chad Sherwood Reder

Loma Linda University Electronic Theses, Dissertations & Projects

Little is known of the effects of proton irradiation on neural tissue. A 1.0 mm microbeam was used on the cat lateral geniculate nucleus (LGN) to quantify the short term (< 3 months) and long term (< 9 months) effects of radiation damage. The LGN is a large structure with well defined afferent, efferent, and receptive field properties.

Electrophysiological and histological techniques were used to examine the effects of the microbeam at 60, 40, and 16 Gy, administered as a single bolus. Recordings of light evoked responses in the LGN were obtained using microelectrodes in nine animals within 12 weeks of irradiation, and 6 animals within 36 weeks of irradiation. Receptive fields were mapped onto a tangent screen using standard receptive field techniques. Histological measures included afferent …

Effects Of Dietary Calcium And Fasting On Osteoclast Recession And Recruitment In Calcium Deficient Rats, Kenneth R. Wright

Loma Linda University Electronic Theses, Dissertations & Projects

The osteoclast, a multinucleated giant cell, has as its role the resorption of bone matrix with consequent release of calcium. The osteoclast is thought to derive from a pluripotent stem cell which also gives rise to monocytes and macrophages. The development, activation, and inhibition of osteoclasts are influenced by a number of systemic and local factors. The release of these factors is influenced by changes in the dietary status of the animal. Calcium deficiency is known to stimulate the recruitment and activity of large numbers of osteoclasts. These osteoclasts can subsequently be inhibited by increasing dietary calcium intake. Disappearance of …

Neurophysiologic Bases For Abnormal Muscle Coactivation Patterns In Hemiparetic Stroke, Julius P.A. Dewald

Loma Linda University Electronic Theses, Dissertations & Projects

To study disturbed muscle activation patterns in hemiparetic stroke, the EMG activity in spastic-paretic and contralateral elbow muscles of 10 stroke subjects were compared during graded directionally varying voluntary isometric contractions. We observed significant shifts in the peak EMG angle and increases in the angular range of EMG activity in the impaired upper limb. Furthermore, we observed stereotypic coactivation of many muscles acting at the same joint or at different joints across all subjects.

The effect of elbow angle changes on muscle coactivation patterns was studied by examining isometric torque-angle relations under passive and active conditions in 8 stroke subjects. …

Plasticity Of The Gnrh Neuronal System During Sexual Maturation Of The Male Djungarian Hamster, Kevin L. Buchanan

Loma Linda University Electronic Theses, Dissertations & Projects

Onset of puberty in male Djungarian hamsters is characterized by increased pituitary gonadotropin secretion and testes maturation, and is controlled by neurons within the brain which secrete gonadotropin-releasing hormone (GnRH). Puberty is associated with increased numbers of morphologically unipolar, but not bipolar, GnRH neurons in the medial preoptic area (MPOA) and diagonal band of Broca (DBB). To test the hypothesis that delayed sexual maturation arrests this increase, males were exposed to short days or administered melatonin. Males with delayed puberty had significantly fewer unipolar GnRH neuron numbers in the MPOA and DBB comparable to pubertal controls in long days. Unipolar …

The Effect Of Ethanol On Bone Histomorphology, Rebecca L. Rodocker

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of ethanol on bone histomorphology was studied using an isocaloric liquid pair feeding system to administer equal amounts of essential vitamins and nutrients to control and ethanol animals.

A bone remodeling sequence was induced in the lower right mandible by removal of the upper right molars. The bone remodeling unit, consisting mainly of the osteoclast and osteoblast, could then be studied microscopically to note any changes brought about by the administration of ethanol.

Although the method of ethanol administration was successful, the induction of unintended bone remodeling via the removal of a solid diet made analysis of the …

Effect Of Age On The Structure Of Meissner Corpuscles In Forepad Digital Pads Of Mice, Roger C. Mathewson

Loma Linda University Electronic Theses, Dissertations & Projects

Meissner corpuscles in forepaw digital pads of albino mice were examined by light and electron microscopy to determine structural age-changes. After 1.5 months of age, no intraepidermal nerve fibers were seen extending from corpuscles. From young (1.5-6 months) to middle age (9-15 months), corpuscles became larger and more complex, gaining more horizontally arranged terminals, associated lamellae and connective tissue. At old age (18-26 months), corpuscles became small and lobulated, appearing disorganized. There was no loosening of the corpuscle-epidermal interface. An increase in collagenous connective tissue and basal lamina duplication occurred with advancing age. Ultrastructural age-changes consisted of disorganization of the …

Topographic Development Of The Corticocollicular Projection In The Neonatal Rat, F. Allen Richburg Ii

Loma Linda University Electronic Theses, Dissertations & Projects

The density and distribution of labeled cortical cells was examined following discrete deposits of retrograde tracers into the superior colliculus (SC) of neonatal and adult rats to study the topographic order of SC afferents from the cortex during the initial phase of axon ingrowth. Small deposits of red and green latex microspheres (0.02-0.05ul) were placed into the SC of rats ranging in age from birth to adulthood using glass micropipettes (tip diameter 25-35um). The animals, following a 48hr survival period, were deeply anesthetized and perfused with normal saline followed by a 10% formal-saline solution. The brains were sectioned coronally at …

Effect Of Photoperiod On Developmental Morphology And Enolase Isoenzyme Immunohistochemistry In Rat And Djungarian Hamster Superficial Pineal Glands, Chalmer D. Mcclure

Loma Linda University Electronic Theses, Dissertations & Projects

The best understood functional activity of the pineal gland is its diurnal production of melatonin in response to environmental lighting cues. Several enzymes of the melatonin pathway respond to daily photoperiod changes, for example hydroxyindole-O-methyltransferase (HIOMT) and serotonin N-acetyltransferase (SNAT). Increased levels of the glycolytic enzyme neuron-specific enolase (NSE) are thought to reflect increased physiological demands placed on neurons and neuroendocrine tissues. Homodimer non-neuronal enolase isoenzyme (NNE) is immunolocalized to cells, and the hybrid enolase (consisting of subunits from NSE and NNE) has been seen in cerebellar stellate and basket cells. Although not rate limiting, concentrations of both NSE and …

Regulation Of Epidermal Growth Factor Receptor Synthesis By Retinoic Acid And Dexamethasone, Kerby C. Oberg

Loma Linda University Electronic Theses, Dissertations & Projects

Fetal rat lung (FRL) cells incubated in the presence of retinoic acid or dexamethasone exhibit altered ¹²⁵I-epidermal growth factor (EOF) binding capacity. Retinoic acid enhances ¹²⁵I-EGF binding 3-fold following 24 hours of 37° incubation. In contrast, FRL cells incubated in the presence of dexamethasone display a 2-fold reduction in ¹²⁵I-EGF binding capacity. The change in binding capacity, induced by either hormone, was due to alterations in the average number of receptors per cell as determined by Scatchard analysis of ¹²⁵I-EGF binding. In the absence of retinoic acid or dexamethasone, FRL cells were calculated to have approximately …

Regeneration Of Meissner Corpuscles In Diabetic Mice Following Median Nerve Crush, Bonnie J. Forrester

Loma Linda University Electronic Theses, Dissertations & Projects

The hyperglycemic metabolic condition found in diabetes mellitus leads to the development of sensory neuropathies and causes delayed and incomplete neuronal regeneration. Diabetic sensory neuropathy has been shown to contribute to the impairment of light touch and low frequency vibratory perception. It is proposed that the regeneration of receptors that detect these sensations will be delayed and incomplete in diabetic animals with uncontrolled hyperglycemia. This study addresses the effects of diabetes on the regeneration of Meissner corpuscles, distal sensory endings that perceive light touch and low frequency vibration.

Corpuscles from 60 diabetic mice, and their age-matched, non-diabetic littermates, were examined …

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 …

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 …

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 …

A Correlational Study Of Mandibular Rotation And Morphology Of The Mandible, Brian S. Noguchi

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Early Osteoclast Responses To A Calcium Supplemented Meal In Calcium Deficient Rats, Eugene E. Joseph

Loma Linda University Electronic Theses, Dissertations & Projects

Osteoclasts are large, irregularly-shaped, multinucleated cells. They are the primary cells responsible for the mobilization of calcium from bone (bone resorption). It is a well known fact that bone diseases (i.e. osteoporosis and osteopetrosis) occur as a result of unbalanced cellular activity. The implicated bone cells include osteoblasts (bone forming cells) and osteoclasts. The earlier one can detect abnormal bone cell function, the more efficient will be the diagnosis and treatment of diseased bone tissue.

Numerous studies have been done on osteoclast morphology and function in vitro (Kallio, et al., 1972; Chambers and Magnus, 1982; Warshafsky, et al., 1985). On …

Hyperosmotic Modification Of Brain Extracellular Space And Blood-Brain Barrier In The Rat As Observed By Electron Microscopy, Susan A. Meacham

Loma Linda University Electronic Theses, Dissertations & Projects

The highly selective permeability of cerebral blood vessels, termed the blood-brain barrier, is due to endothelial tight junctions (zonulae occludentes). Hyperosmotic solutions reversibly open the blood-brain barrier. The purpose of this study is to determine the immediate effect of hyperosmotic arabinose perfusion upon the cerebrovascular endothelium, the morphology of the cerebral cortex, and the cortical extracellular space.

Twelve adult male Sprague-Dawley rats were separated into three groups of four animals each: control, intermediate, and extreme. Controls were perfused with a Tyrode's solution prewash followed by trialdehyde fixative. The intermediate group received a prewash of 740 mmol/kg arabinose followed by the …

Fetal Whole-Body Fluid, Cardiovascular And Endocrine Dynamics : Computer Analysis Of Regulatory Mechanisms, Peter Stuart Gold

Loma Linda University Electronic Theses, Dissertations & Projects

The dynamics of transcapillary fluid and protein distribution and endocrine regulation of cardiovascular function were studied in chronically instrumented fetal sheep during the third trimester. Average experimental changes in vascular pressures, blood volume, plasma hormone concentrations, hematocrit and plasma protein concentration were analyzed using mathematical modeling and parameter optimization techniques in order to determine values for the major parameters which regulate fluid, protein and endocrine dynamics and to determine endocrine dose-response relationships to changes in cardiovascular function. The hormones which were considered are arginine vasopressin (AVP), angiotensin II (AII), epinephrine (EPI) and norepinephrine (NE). Vascular disturbances which were considered include …