Medical Physiology Commons^™

Selection Of Genetic Variants Of Simian Immunodeficiency Virus In Persistently Infected Rhesus Monkeys, Dawn P. Wooley, Ronald C. Desrosiers

Neuroscience, Cell Biology & Physiology Faculty Publications

Genetic and antigenic variation may be one means by which lentiviruses that cause AIDS avoid elimination by host immune responses. Genetic variation in the envelope gene (env) was studied by comparing the nucleotide sequences of 27 clones obtained from two rhesus monkeys infected with molecularly cloned simian immunodeficiency virus. All 27 clones differed from each other and differed from the input clone in the gp120 (SU) portion of the envelope gene. Nucleotide substitutions were shown to accumulate with time at an average rate of 8.5 per 1,000 per year in SU. Surprisingly, the majority of nucleotide substitutions (81%) resulted in …

Significance Of Premature Stop Codons In Env Of Simian Immunodeficiency Virus, Toshiaki Kodama, Dawn P. Wooley, Yathirajulu M. Naidu, Harry W. Kestler Iii, Muthiah D. Daniel, Yen Li, Ronald C. Desrosiers

Neuroscience, Cell Biology & Physiology Faculty Publications

The location of the translational termination codon for the transmembrane protein (TMP) varies in three infectious molecular clones of simian immunodeficiency virus from macaques (SIV_mac). The SIV_mac251 and SIV_mac142 infectious clones have premature stop signals that differ in location by one codon; transfection of these DNAs into human HUT-78 cells yielded virus with a truncated TMP (28 to 30 kilodaltons [kDa]). The SIV_mac239 infectious clone does not have a premature stop codon in its TMP-coding region. Transfection of HUT-78 cells with this clone initially yielded virus with a full-length TMP (41 kDa). …

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 …

Aldosterone Stimulates K Secretion Across Mammalian Colon Independent Of Na Absorption, Gerhard Rechkemmer, Dan R. Halm

Neuroscience, Cell Biology & Physiology Faculty Publications

K transport across guinea pig (Cavia porcellus) distal colon was measured in vitro using isotopically determined unidirectional fluxes. Aldosterone stimulated electrogenic Na absorption, as measured by amiloride-sensitive short-circuit current (I_sc), and reduced net K absorption from +2.5 ± 0.2 µEq/cm² per hr to +0.8 ± 0.3 µEq/cm² per hr (mean ± SEM). Amiloride addition to the mucosal solution did not enhance net K absorption, as expected if inhibiting active Na absorption would reduce active K secretion as in the distal nephron. The amiloride-insensitive I_sc was -1.0 ± 0.2 µEq/cm² per hr (mean ± SEM) …

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. …

Application Of Digital Signal Analysis, Mass Data Acquisition And Processing Techniques, And Automated Experiment Protocols To The Study Of Cardiac Cell Membrane Electrophysiology, With Mathematical Modeling, David S. Buckles

MUSC Theses and Dissertations

Traditional methods of collecting, analyzing and storing data from cardiac cell membrane electrophysiology experiments have become increasingly cumbersome and unwieldy as experimental protocols have become more sophisticated and complex. A global approach to collecting, analyzing, refining and storing electrophysiologic data, as well as a new approach to mathematical modeling of cell membrane single ion channel kinetics, was developed. This utilizes a comprehensive microcomputer based system of software with specialized analog and digital electronics for data acquisition, analysis and archiving. Unique discrete signal processing techniques for characterizing the electronic recording system, including specialized hardware and software adapted for minimizing distortions in …

Physiological Differentiation And Cognitive Discrimination Of An Olfactory Stimulus Produced Under Stress, Robert Gray Perra

Dissertations

Humans may have ability to transmit, receive, and react to biological information from other humans through olfactory chemosensory communication. Two studies examined human (1) ability to differentiate physiologically, via olfaction, fresh stress produced sweat and (2) cognitive discrimination, through smell, of "aged" stress produced sweat. Four stress conditions were employed; (1) exercise, (2) relaxation, (3) sexual arousal, and (4) repulsion.

Experiment I. A male dyad participated--donor and recipient. Donor was prepared to collect his axillary secretion on gauze; following preparation donor was stressed. After stressing, the gauze which was presumed to contain a fresh non-odoriferous sweat, was removed, sandwiched between …

The Effects Of Cigarette Smoking And Vitamin E On The Morphology Of Mice Testes, Kathleen Grams Hall

Masters Theses

Epidemiological studies have produced evidence to support an association between cigarette smoking and abnormal sperm morphology. At the least , an effect on sperm morphology indicates the involvement of the testis. Therefore, the research was designed to survey the potential of cigarette smoking for inducing histopathology in the testes of mice, and if there was damage, would vitamin E overcome it.

In the present study the testes of C57BL/6 mive exposed to cigarette smoke and/or vitamin E and 22 control mice were histologically processed. Sections stained with hematoxylin and eosin were assessed for total histopathology and revealed statistically significant differences …

Electrophysiology Of Flounder Intestinal Mucosa. I. Conductance Properties Ofthe Cellular And Paracellular Pathways, Dan R. Halm, Edward J. Krasny Jr., Raymond A. Frizzell

Neuroscience, Cell Biology & Physiology Faculty Publications

We evaluated the conductances for ion flow across the cellular and paracellular pathways of flounder intestine using microelectrode techniques and ion-replacement studies. Apical membrane conductance properties are dominated by the presence of Ba-sensitive K channels. An elevated mucosal solution K concentration, [K]_m, depolarized the apical membrane potential (ψ_a) and, at [K]_m less than 40 mM, the K dependence of ψ_a was abolished by 1-2 mM mucosal Ba. The basolateral membrane displayed Cl conductance behavior, as evidenced by depolarization of the basolateral membrane potential (ψ_b) with reduced serosal Cl concentrations, [Cl]_s. …

Electrophysiology Of Flounder Intestinal Mucosa. Ii. Relation Of The Electrical Potential Profile To Coupled Nacl Absorption, Dan R. Halm, Edward J. Krasny Jr., Raymond A. Frizzell

Neuroscience, Cell Biology & Physiology Faculty Publications

We characterized the hyperpolarization of the electrical potential profile of flounder intestinal cells that accompanies inhibition of NaCl cotransport. Several observations indicate that hyperpolarization of ψ_a and ψ_b (Δψ_a,b) results from inhibition of NaCl entry across the apical membrane: (a) the response was elicited by replacement of mucosal solution Cl or Na by nontransported ions, and (b) mucosal bumetanide or serosal cGMP, inhibitors of NaCl influx, elicited Δψ_a,b and decreased the transepithelial potential (ψ_t) in parallel. Regardless of initial values, ψ_a and ψ_b approached the equilibrium potential for K (E^{K …}

Metabolism In Preimplantation Mouse Embryos, Harry M. Weitlauf, Gary L. Nieder

Neuroscience, Cell Biology & Physiology Faculty Publications

The ability of preimplantation mouse embryos to utilize glucose oxidatively is controlled, in part at least, at the level of glycolysis. Various experimental observations are reviewed that indicate the regulatory mechanism in delayed implanting blastocysts involves the classic negative allosteric feedback of high levels of ATP on phosphofructokinase while the situation in 2-cell embryos appears to be more complicated. That is, in addition to the usual negative effect of ATP and citrate on phosphofructokinase, there appears to be a modification of hexokinase that prevents phosphorylation of adequate amounts of glucose and results in low levels of fructose-6-phosphate at the 2-cell …

Development Of A Mathematical Model Of Renal Function For Clinical Application, Barbara A. Holshouser

Loma Linda University Electronic Theses, Dissertations & Projects

This model describes the orthoiodohippurate (OIH) distribution and clearance in the renovascular system. The model is described by five compartments: the blood, left and right kidneys, bladder and the red blood cell compartment. Data for these compartments, except the RBC compartment, are collected with scintillation detectors monitoring OIH tagged with 1-131 as the radiopharmaceutical passes through each compartment. Time/ activity curves are plotted for the data and used as inputs to the model parameter estimation routine. The compartments are described by a set of first order ordinary differential equations solved using the Adam's methods. For parameter estimation, an iterative predictor-corrector …

T Cell Growth Factor Receptors. Quantitation, Specificity, And Biological Relevance, Richard J. Robb, Allen Munck, Kendall A. Smith

Dartmouth Scholarship

To examine directly the hypothesis that T cell growth factor (TCGF) interacts with target cells in a fashion similar to polypeptide hormones, the binding of radiolabeled TCGF to various cell populations was investigated. The results indicate that TCGF interacts with activated T cells via a receptor through which it initiates the T cell proliferative response. Internally radiolabeled TCGF, prepared from a human T leukemia cell line and purified by gel filtration and isoelectric focusing, retained biological activity and was uniform with respect to size and charge. Binding of radiolabeled TCGF to TCGF-dependent cytolytic T cells occurred rapidly (within 15 rain …

Rabbit Erythropoiesis In Vitro, K. G. M. Brockbank

MUSC Theses and Dissertations

The erythropoietin (Ep) dose response of erythroid colony-forming units (CFU-e) and erythroid burst-forming units (BFU-e) from rabbit bone were similar to murine erythroid precursor Ep requirements. Bone marrow and peripheral blood contained a continuum of erythroid precursors at differing stages of maturation. The earliest BFU-e were assayed on day 10. CFU-e were observed in bone marrow, but not in peripheral blood. The most mature erythroid precursors observed in peripheral blood were intermediate BFU-e, assayed on day 5. A linear relationship exists between the number of nucleated bone marrow cells plated and the number of 3 day colonies and 10 day …

Carbon Dioxide Contributions In Respiratory Control, Edwin Merrill Adams

MUSC Theses and Dissertations

This study was undertaken to investigate the contribution of carbon dioxide to respiratory control made by the carotid bodies and vagus nerves. Small eupneically breathing dogs, anesthetized with IV ketamine HCL were subjected to inspired CO2 concentrations of 3% while recording simultaneously tidal volume, inspiratory and expiratory airflow rates, and single neuron activity in or near the ventral respiratory group. The burst activity of the ventral respiratory group neuron was considered to be representative of the final integrated motor output of the brain stem respiratory complex. This data provided information concerning: (1) the relationship between the central respiratory neuron in …

Acid-Base Disorders: Evaluation And Instruction By Minicomputer, Deborah Likins Atkinson

MUSC Theses and Dissertations

A computerized system for instruction and diagnosis of clinical electrolyte and acid-base disorders has been implemented on a PDP-8/e minicomputer at the Medical University of South Carolina. The program is designed for use by persons at various stages of medical training: student, house staff, and clinician. This system not only aids the physician in making his diagnosis, but also serves as a means of educational instruction in acid-base physiology for the student. A patient file has been established in conjunction with the program. The file enables a physician to follow a patient's course over time. Several auxiliary computer programs have …

Evidence For Bone Marrow Cell Attrition As A Mechanism For Granulocyte Regulation In The Canine, Vincent Dee Smith

Theses and Dissertations (ETD)

No abstract provided.

The Effect Of Glucose On The Food Intake Of Goldthioglucose Injected Mice, Janet Lahti

Dissertations and Theses

Jean Mayer has postulated the presence of glucoreceptors located primarily in the ventromedial hypothalamic nuclei of the brain which are activated by glucose in the measure that they utilize it. According to Mayer, hunger occurs when glucose is not available for metabolic purposes and satiation supervenes when glucose is made available. Control of this mechanism rests with the glucoreceptors. These receptors are believed to be destroyed when an injection of the compound goldthioglucose is given to mice. These animals subsequently become obese and are found to have gold deposits and lesions in the ventromedial area and also in other parts …

The Development Of Electrophysiological Techniques Allowing "In Situ" Measurement Of Electrical Changes Within Smooth Muscle Cells Of Mesenteric Micro-Vessels, William J. Willems

Master's Essays (1922 - )

The primary objective or this study is essentially to acquire further knowledge of the factors involved in the nervous and humoral control of vascular smooth muscle tone. The relative importance of the nervous and endogenous vasotropic humoral control or vasomotor tone under normal conditions as well as under conditions or hypotension can be evaluated, at least in part, by observing the electrical activity occurring in single vascular smooth muscle cells of the mesenteric microcirculation. This thesis describes: 1) the development of electrophysiological methods for the measurement of such activity in ''in situ" micro-vessels with circulation and innervation intact, and 2) …

The Improvement Of Peripheral Blood Flow During Hemorrhagic Hypotension Following Phenoxybenzamine Treatment Expressed In Terms Of Extracellular Potassium Shifts, Thomas J. Wera

Master's Essays (1922 - )

The study of plasma electrolytes notably, the potassium and sodium ions during hemorrhagic stress and other forms of shock, were once the subject of intense investigation (42). However, the advent of new investigative techniques enabled more complex, experimental designs and methods to be used in which it was possible to study the many other variables which exist as a result of shock regardless of cause. The proponents of the probable electrolyte mechanism in shock subsequently diminished in numbers until recent times.

It is felt by this author that recent renewal regarding the various ions, especially the cations, sodium and potassium …

Effects Of Music Therapy And Personal Interaction On The Preoperative Patient, Phyllis Jean Nix

Loma Linda University Electronic Theses, Dissertations & Projects

This study was conducted to discover the effects of (1) an interpersonal relationship and (2) an interpersonal relationship and music therapy on preoperative patients in a selected hospital.

The descriptive survey was chosen as the method of study. A checklist and a tape recording of selected music were used as a tool of research. Two groups of preoperative patients were given nursing care by the researcher. Patients in Group One received care with an aim toward developing an interpersonal relationship, while patients in Group Two received the same as Group One with the addition of music therapy.

Findings revealed a …

The Effects Of Reserpine On Adrenal Responses To Nicotine And On Cardiovascular Responses To Exogenous Epinephrine And Norepinephrine, Ervin E. Bagwell

MUSC Theses and Dissertations

Since the isolation or reserpine by Bein et al (1) in 1952, there have been numerous investigations dealing with the pharmacological and physiological properties of this drug. A good proportion of this work has dealt with the effects of reserpine on the function of the sympatho-adrenal system. The present investigation has two primary objectives and is therefore divided into two chapters. The first chapter is concerned with a study of the effects of previous reserpine treatment on the responsiveness of the adrenal medulla to chemical stimulation and the reactivity of the cardiovascular system to this stimulation. In chapter two an …

Pathological Physiology As A Basis For Medical Practice, Walter E. Macpherson

Medical Arts and Sciences: A Scientific Journal of the College of Medical Evangelists

No abstract provided.

Physiology And Mental Science, A. T. Ormond

Journal of the Minnesota Academy of Science

No abstract provided.