Physiology Commons^™

Electromagnetic Differences In The Brain During Memory Retrieval, Warren Scott Merrifield

Loma Linda University Electronic Theses, Dissertations & Projects

The primary objectives for this experiment were to analyze the neuroanatomical correlates of autobiographical, episodic and semantic memory, use a different paradigm to promote episodic memory retrieval, and employ a different analysis technique to understand retrieval processes. Autobiographical and episodic memories are personal memories from the past. Autobiographical is more general (e.g. a street name of a house growing up) and episodic is more specific to time (e.g. 13th birthday party that took place on a street). For autobiographical and episodic memory retrieval operations, there is no general consensus as to the localization of function, but bilateral activation of the …

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 …

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 …

Activation In Neural Networks Controlling Ingestive Behaviors: What Does It Mean, And How Do We Map And Measure It?, Alan Watts, Arshad Khan, Graciela Sanchez-Watts, Dawna Salter, Christina Neuner

Selected Works Temporary Series

No abstract provided.

Activation In Neural Networks Controlling Ingestive Behaviors: What Does It Mean, And How Do We Map And Measure It?, Watts, Arshad Khan, Graciela Sanchez-Watts, Dawna Salter, Christina Neuner

Departmental Papers (Biology)

No abstract provided.

Mechanisms Of Hbo-Induced Neuroprotection In A Neonatal Hypoxia-Ischemia Model, John Winter Calvert

Loma Linda University Electronic Theses, Dissertations & Projects

With an incidence approaching 1/4000 live births and as high as 60% in low birth weight infants, cerebral hypoxia-ischemia during the perinatal period is the single most important cause of acute mortality and chronic disability in newborns. Herein, we tested the hypothesis that following a hypoxic-ischemic insult hyperbaric oxygen (HBO) treatment can restore high energy metabolite levels in the affected regions of the brain and through this increase in energy levels ameliorate the spread of cell death following the insult. We also investigated if an additional mechanism by which HBO affords its neuroprotection is by altering the expression of the …

Lateral Hypothalamic Signaling Mechanisms Underlying Feeding Stimulation: Differential Contributions Of Src Family Tyrosine Kinases To Feeding Triggered Either By Nmda Injection Or By Food Deprivation, Arshad Khan, Herman Cheung, Elizabeth Gillard, Jennifer Palarca, Derek Welsbie, James Gurd, B. Stanley

Selected Works Temporary Series

No abstract provided.

Lateral Hypothalamic Signaling Mechanisms Underlying Feeding Stimulation: Differential Contributions Of Src Family Tyrosine Kinases To Feeding Triggered Either By Nmda Injection Or By Food Deprivation, Khan, Herman Cheung, Elizabeth Gillard, Jennifer Palarca, Derek Welsbie, James Gurd, B. Stanley

Departmental Papers (Biology)

No abstract provided.

Intravenous 2-Deoxy-D-Glucose Injection Rapidly Elevates Levels Of The Phosphorylated Forms Of P44/42 Mitogen-Activated Protein Kinases (Extracellularly Regulated Kinases 1/2) In Rat Hypothalamic Parvicellular Paraventricular Neurons, Arshad Khan, Alan Watts

Selected Works Temporary Series

No abstract provided.

Intravenous 2-Deoxy-D-Glucose Injection Rapidly Elevates Levels Of The Phosphorylated Forms Of P44/42 Mitogen-Activated Protein Kinases (Extracellularly Regulated Kinases 1/2) In Rat Hypothalamic Parvicellular Paraventricular Neurons, Khan, Alan Watts

Departmental Papers (Biology)

No abstract provided.

Prediction Of Fetal Sheep Brain Metabolic Rate During Hypoxia And Cord Occlusion, Adam D. Hickerson

Loma Linda University Electronic Theses, Dissertations & Projects

Many investigators have observed that fetal and neonatal animals are remarkably tolerant to hypoxia compared to the adult. The precise mechanisms however are still unclear. In order to better characterize the hemodynamic and metabolic responses of the fetal brain to hypoxic stress, we have designed a mathematical model to predict tissue oxygenation and metabolic rate of the fetal brain during both moderate hypoxia and severe asphyxia.

The model is based on the Krogh cylinder concept and is similar to one previously published by our lab. Several new concepts were added including the ability to run the model over time using …

Interaction Between Adrenergic And Nitric Oxide-Releasing Nerves In Cerebral Arteries, Emmanuel Ngu Mbaku

Loma Linda University Electronic Theses, Dissertations & Projects

Of all body tissues, the brain is the least tolerant of ischemia so much that interruption of cerebral blood flow by 5 sec can cause syncope, with irreversible tissue damage if the ischemia last a few minutes. In this respect, the body has an imperative duty of ensuring constant and adequate blood supply to the brain. It does so through a series of intrinsic and extrinsic control factors of which adrenergic and nitric oxide-releasing nerves are components. My research examined the interaction between these two nerve-types with emphasis on the mechanisms involved as well as on changes in their functions …

Hiv Protease Inhibitors Promote Atherosclerotic Lesion Formation Independent Of Dyslipidemia By Increasing Cd36-Dependent Cholesteryl Ester Accumulation In Macrophages, James Dressman, Jeanie Kincer, Sergey V. Matveev, Ling Guo, Richard N. Greenberg, Theresa Guerin, David Meade, Xiang-An Li, Weifei Zhu, Annette M. Uittenbogaard, Melinda E. Wilson, Eric J. Smart

Physiology Faculty Publications

Protease inhibitors decrease the viral load in HIV patients, however the patients develop hypertriglyceridemia, hypercholesterolemia, and atherosclerosis. It has been assumed that protease inhibitor–dependent increases in atherosclerosis are secondary to the dyslipidemia. Incubation of THP-1 cells or human PBMCs with protease inhibitors caused upregulation of CD36 and the accumulation of cholesteryl esters. The use of CD36-blocking antibodies, a CD36 morpholino, and monocytes isolated from CD36 null mice demonstrated that protease inhibitor–induced increases in cholesteryl esters were dependent on CD36 upregulation. These data led to the hypothesis that protease inhibitors induce foam cell formation and consequently atherosclerosis by upregulating CD36 and …

Chronic Hypoxia, Exercise Training, And Skeletal Muscle Capillarity: Angiogenic Regulation And Morphological Consequences, Ivan Mark Olfert

Loma Linda University Electronic Theses, Dissertations & Projects

Angiogenesis is important in health and disease. In particular, exercise training is known to increase skeletal muscle capillarity, providing there is sufficient training intensity. The stimulus for this may be intracellular hypoxia activating angiogenic growth factor gene expression. Acute hypoxia alone has been shown to increase the gene expression of several key angiogenic regulators, e.g. vascular endothelial growth factor (VEGF) and to a lesser degree transforming growth factor-β1 (TGF-β1), basic fibroblast growth factor (bFGF), and thrombospondin-1 (TSP-1), an endogenous negative angiogenic regulator. Paradoxically, however, chronic hypoxia is generally not found to increase mammalian skeletal muscle capillarity. Accordingly, we hypothesized that …

Lateral Hypothalamic Nmda Receptor Subunits Nr2a And/Or Nr2b Mediate Eating: Immunochemical/Behavioral Evidence, Arshad Khan, Margarita Curras, Jennifer Dao, Faizi Jamal, Rishi Goel, Elizabeth Gillard, Stefany Wolfsohn, B. Stanley

Selected Works Temporary Series

No abstract provided.

Lateral Hypothalamic Nmda Receptor Subunits Nr2a And/Or Nr2b Mediate Eating: Immunochemical/Behavioral Evidence, Khan, Margarita Curras, Jennifer Dao, Faizi Jamal, Rishi Goel, Elizabeth Gillard, Stefany Wolfsohn, B. Stanley

Departmental Papers (Biology)

No abstract provided.

Regeneration Of Hair Cell Epithelia In The Chick And Salamander, Kenneth Detwiler

Masters Theses & Specialist Projects

The acousticolateralis sensory system is characterized by a specific receptor cell type called the sensory hair cell and is found in all vertebrates. There are two types of hair cell sensory epithelia based on location: those of the inner ear, such as the organs for hearing and balance, and the lateral line system located within the epidermis. In mammals, including humans, loss or damage of the hair cells of the auditorysystem results in permanent hearing loss. However, this is not the case with birds and amphibians. Amphibians, with a lateral line system, are capable of replacing lost or damaged hair …

The Role Of Gap Junctions In Congenital Diseases Of The Heart, Scott Henry Britz-Cunningham

Loma Linda University Electronic Theses, Dissertations & Projects

Background. Gap junctions are thought to have a crucial role in the synchronized contraction of the heart and in embryonic development. Connexin43, the major protein of gap junctions in the heart, is targeted by several protein kinases that regulate myocardial cell-cell coupling. We hypothesized that mutations altering sites critical to this regulation would lead to functional or developmental abnormalities of the heart.

Methods. Connexin43 DNA from 25 normal subjects and 30 children with a variety of congenital heart diseases was amplified by the polymerase chain reaction and sequenced. Mutant DNA was expressed in cell culture and examined for its effect …

The Second Messenger Camp Elicits Eating By An Anatomically Specific Action In The Perifornical Hypothalamus, Elizabeth Gillard, Arshad Khan, Rickinder Grewal, Bara Mouradi, Stefany Wolfsohn, B. Stanley

Selected Works Temporary Series

No abstract provided.

The Second Messenger Camp Elicits Eating By An Anatomically Specific Action In The Perifornical Hypothalamus, Gillard, Arshad Khan, Rickinder Grewal, Bara Mouradi, Stefany Wolfsohn, B. Stanley

Departmental Papers (Biology)

No abstract provided.

Eating Induced By Perifornical Camp Is Behaviorally Selective And Involves Protein Kinase Activity, Elizabeth Gillard, Arshad Khan, Bara Mouradi, Omkar Nalamwar, B. Stanley

Selected Works Temporary Series

No abstract provided.

Eating Induced By Perifornical Camp Is Behaviorally Selective And Involves Protein Kinase Activity, Gillard, Arshad Khan, Bara Mouradi, Omkar Nalamwar, B. Stanley

Departmental Papers (Biology)

No abstract provided.

Cellular Responses In Escherichia Coli To Lethal And Sublethal Doses Of Ozone, Indira Ruth Komanapalli

Loma Linda University Electronic Theses, Dissertations & Projects

Ozone is a major component of photochemical smog. High levels of this pollutant, sufficient to affect human health are found in many urban areas worldwide. Though limited studies in humans are supported by extensive findings from animal experiments, a difficulty in interpreting the results of these experiments has lead to an ambiguity on the biochemical mechanism of ozone toxicity. To elucidate the mechanism by which ozone causes cell damage and eventual cell death we conducted a comprehensive study using Escherichia coli K-12 as a model.

Studies on the comparative inactivation of bacteriophage lambda (λ), Escherichia coli, and Candida albicans …

The Role Of Fas And Fas Ligand In Apoptosis During Regression Of The Corpus Luteum, Sharon Roughton

Theses : Honours

Apoptosis, a form of physiological cell death, has been found to occur during regression of the corpus luteum (Juengel etal, 1993; Dharmarajan etal, 1994). The pathways involved in this process, however, have yet to be specified. One possible mediator of corpus luteum regression is the Fas (or AP0-1 or CD95) receptor, a transmembrane protein which induces apoptosis in the cell when ligated. In order to further confirm this hypolhesis, the present study establishes and quantitates the presence and regulation of Fas receptor and Fas ligand (Fasl) in the rat corpus luteum during pregnancy and post-partum. The animals used were sexually …

Thymic Peptide Modulates Glutathione Redox Cycle And Antioxidant Enzymes In Macrophages, Choon Sil Park

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of a 6-kDa thymic peptide (TP) on the oxidative burst of a murine macrophage cell line J774 was determined. TP (12.5-200 μg/ml) was incubated with 5 x 10⁵ J774 cells at 37° C and 5% C0₂ for 18 h and oxidative burst was triggered by zymosan; chemiluminescence was amplified by luminol and measured in an automated luminometer. TP exhibited a concentration-dependent inhibition of oxidative burst. To study the mechanisms involved in TP’s inhibition of oxidative burst, its effect on the glutathione (GSH) redox cycle, GSH biosynthesis, and antioxidant enzymes was investigated. TP was shown to increase …

Catecholamines And The Regulation Of Uterine Contractions In The Pregnant Rhesus Macaque, Cahleen Mae Mcnutt

Loma Linda University Electronic Theses, Dissertations & Projects

This study was designed to test the hypothesis that: 1) maternal and/or amniotic fluid catecholamines or prostaglandins display nocturnal activity rhythms similar to those of the myometrial contractility in the pregnant rhesus macaque and, 2) catecholamines stimulate prostaglandin production by fetal membranes. Paired maternal arterial blood and amniotic fluid samples were collected at 0900 h (AM) and 2100 h (PM) from chronically catheterized rhesus macaques until delivery and analyzed for prostaglandin metabolites (PGFM and PGEM-II) and catecholamines (norepinephrine, epinephrine, and dopamine). Uterine activity data was continuously recorded. A rhythm in uterine contractility was observed, with peak activity between 1900 and …

Effect Of Glucose Administration On Hamster Liver S9-Mediated Mutagenesis, Metabolism And Dna-Binding Of Benzo[A]Pyrene And Aflatoxin B1, Daniel C. Rubano

Loma Linda University Electronic Theses, Dissertations & Projects

Hamster liver S9 prepared from control animals and animals given 30% glucose in drinking water 48 h before time of sacrifice was used in studies of benzo[a]pyrene (BaP) and aflatoxin (AFB₁)-induced mutagenesis, metabolism of BaP and AFB₁, and metabolite binding to calf thymus DNA. BaP-induced mutagenesis in Salmonella typhimurium TA100 was reduced 38.5% while AFB₁-induced mutagenesis was increased 36% by S9 from glucose-treated hamsters. The reduction of [³H]BaP metabolite binding to calf thymus DNA in incubations with S9 from glucose-treated hamsters correlated with a decrease in unknown BaP metabolite-deoxyribonucleoside adducts isolated by …

Characterization Of Hsd::Mudx128 Operon Fusion Mutant Of Escherichia Coli K-12, Marjorie Ann T. Reyno

Loma Linda University Electronic Theses, Dissertations & Projects

The study of the regulation of gene expression in complex genes can be facilitated by the use of operon fusions which place a well characterized lacZ gene under the control of a promoter of interest. An hsd::MudX128 operon fusion mutant of E. coli K-12 isolated by Prakash (1986) was observed to have a high β-galactosidase activity (1000 units), ten to twenty times higher than other hsd::MudX mutants. This β-galactosidase activity was suppressed to a very low level (25 units) by the introduction of an F’ plasmid, F'101, which carries the 98 min to 2 min region of the …

Autonomic Nervous System And Cholesterol Transport, Yuan-Line Hung

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of autonomic nervous system on cholesterol transport is of clinical interest because the relationship between lipoprotein metabolism and atherogenesis is expressed in coronary artery disease.

Generally speaking, beta blockers increase serum VLDL level but decrease both HDL and HDL₂ cholesterol levels without affecting the LDL in humans. We are unaware of reports concerning the effects of metoprolol on lipoprotein metabolism nor comparison of the effects of metoprolol and propranolol in the unhandled rat model. In part I we employed the unhandled rats to compared the effects of these 2 drugs administered with the drinking water in order …

Extrathyroidal Human Biochemistry Of Monoiodotyrosine, Stanley Andrew Tan

Loma Linda University Electronic Theses, Dissertations & Projects

The existence of extrathyroidal monoiodotyrosine (MIT) has been debated because of uncertain results from measuring serum MIT. The reason is that the isotopic and chromatographic assays used have not been sensitive enough. This investigation undertook to establish the existence of MIT in serum utilizing a radioimmunoassay (RIA), to study the physiology of serum MIT, and to discover the pharmacologic effects of exogenous MIT.

MIT-binding antibody was raised in rabbits by immunization with an MIT-porcine thyroglobulin conjugate. The antiserum bound 40% of the labeled MIT at a final dilution of 1:1000. Incubation of 100 µ1 antiserum with 50 pg [^{125 …}