Medicine and Health Sciences Commons^™

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 …

Full Issue, Vol. 12

Great Basin Naturalist Memoirs

No abstract provided.

End Matter, Vol. 12, Index

Great Basin Naturalist Memoirs

No abstract provided.

Front Matter, Vol. 12

Great Basin Naturalist Memoirs

No abstract provided.

End Matter, Vol. 12

Great Basin Naturalist Memoirs

No abstract provided.

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 …

Computer Analysis Of Cross Sections Of Leaves Of Chrysothamnus Taxa And Their Relation To Environmental Conditions, J. Huang, W. M. Hess, D. J. Weber, E. D. Mcarthur, S. E. Meyer, R. Seegmiller

Great Basin Naturalist

Thirty-eight accessions of 20 taxa (species and subspecies) of Chrysothamnus from a range of environments were grown in a uniform garden. During mid-June, terminal and lateral leaves were removed, fixed, and processed for light-microscopy studies. Area and perimeter measurements of ink tracings of midleaf vein cross sections were measured using computer-scan techniques. Leaf area and perimeter were compared with vein perimeter and area measurements. Area and perimeter of these Chrysothamnus leaves varied in response to the environment at the collection location. Plants native to hot, dry conditions had small, thick leaves, whereas plants native to cooler, more mesic conditions had …

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 …

A Biomechanical Analysis Of The Effect Wear Patterns Of Running Shoes Have On Kinematic Variables Of The Lower Extremities, Audrey E. Randall

Masters Theses

The purpose of the study was to investigate the relationship between wear patterns of running shoes and selected kinematic variables of the lower extremities. Statistical analyses were completed by using a case study design for two male subjects. Subjects were filmed for ten strides on six different sessions over a three-month period. A two-way ANOVA design, with repeated measures, evaluated the dependent variables: (a) footstrike, (b) midstance and (c) toeoff phases. The degree of change was determined by digitizing ten points on the body. A University of California, Los Angeles, BMDP2V statistical package was used to determine differences between means. …

Laminin Receptors For Neurite Formation, H. K. Kleinman, Roy C. Ogle, F. B. Cannon, C. D. Little, T. M. Sweeney, L. Luckenbill-Edds

School of Medical Diagnostics & Translational Sciences Faculty Publications

Laminin, a basement membrane glycoprotein promotes both cell attachment and neurite outgrowth. Separate domains on laminin elicit these responses, suggesting that distinct receptors occur on the surface of cells. NG108-15 neuroblastoma-glioma cells rapidly extend long processes in the presence of laminin. We report here that 125I-labeled laminin specifically binds to these cells and to three membrane proteins of 67, 110, and 180 kDa. These proteins were isolated by affinity chromatography on laminin-Sepharose. The 67-kDa protein reacted with antibody to the previously characterized receptor for cell attachment to laminin. Antibodies to the 110-kDa and 180-kDa bands demonstrated that the 110-kDa protein …

The Parabrachial Nucleus In The Rat: An Immunhistochemical Study Of Its Forebrain Neural Input, Margaret M. Moga

Dissertations

No abstract provided.

A Study Of Corticospinal Tract Remodelling In Adult Rats That Sustained Unilateral Cortical Ablation At Birth, Blesilda Reinoso

Dissertations

No abstract provided.

A Stereotaxic Atlas Of The Brain Of The Chick (Gallus Domesticus), Wayne J. Kuenzel, Manju Masson

Poultry Science Faculty Publications and Presentations

Nine brains taken from chicks two weeks of age were used for the development of this atlas. Each chick was first anesthetized with an intravenous (IV) injection of Chloropent2 (1.8 ml/kg). Chicks were then perfused via the heart with 90 ml physiological saline followed by 90 ml Heidenhain's3 solution. Each head was then positioned in a stereotaxic instrument as described in the previous section and three stainless steel (SS) insect pins (#2) were implanted in each brain at known coordinates. In the case of the brains used to construct the cross- sectional atlas plates, two pins were implanted horizontal to …

An Anatomical, Electrophysiological, And Behavioral Study Of The Effects Of Partial Mid-Thoracic Spinal Cord Lesions On Neonatal And Adult Rats, Michael F. Dauzvardis

Dissertations

No abstract provided.

Eavesdropping By Bats: The Influence Of Echolocation Call Design And Foraging Strategy, Jonathan Balcombe, M. Brock Fenton

Sentience Collection

We used playback presentations to free-flying bats of 3 species to assess the influence of echolocation call design and foraging strategy on the role of echolocation calls in communication. Near feeding sites over water, Myotis lucifugus and M. yumanensis responded positively only to echolocation calls of conspecifics. Near roosts, these bats did not respond before young of the year became volant, and after this responded to presentations of echolocation calls of similar and dissimilar design. At feeding sites Lasiurus borealis responded only to echolocation calls of conspecifics and particularly to "feeding buzzes". While Myotis, particularly subadults, appear to use the …

Corticosteroid Effects And Senescence In Cultured Endothelium, Stephen A. Gudas

Theses and Dissertations

Cultures of human umbilical vein endothelial cells were treated with heparin-corticosteroid combinations to determine effects on cellular growth. Standard proliferation assays, colony formation assays, and cytoflourometric analysis were the methods employed. Dexamethasone (DEX) and hydrocortisone (HC) were inhibitory to growth of HUVEC when EtOH was used as a solvent and fully supplemented medium (20% serum) was employed. When DMSO was the solvent, growth enhancement sometimes occurred when (DEX) was the test steroid; growth inhibition occurred with this steroid when a reduced (1%) serum component was used. Since significant inhibition of cell colony formation in response to DEX administration was observed, …