Physiology Commons^™

Estrogen Regulation Of The Pregnant Baboon Placental 11Β-Hydroxysteroid Dehydrogenase (11Β-Hsd)-Catalyzed Metabolism Of Cortisol And Cortisone And Its Effect On The Development Of The Fetal Hypothalamic-Pituitary-Adrenal Axis, William Adair Davies

Theses and Dissertations in Biomedical Sciences

Pepe and Albrecht previously demonstrated that the estrogen-regulated change in transuteroplacental metabolism of cortisol (F) and cortisone (E) from preferential reduction (E to F) at midgestation to oxidation (F to E) near term results in a decline of bioactive cortisol crossing the placenta and reaching the fetus culminating in activation of the hypothalamic-pituitary adrenal axis of the baboon and the ontogenesis of rate-limiting steroidogenic enzymes culminating in de novo F secretion. Protein kinase A (PK-A) activity in the baboon fetal adrenal gland cytosolic fraction was increased 2-fold both at term [day 165 of gestation (term = 184 days)] and following …

Bronchodilator, Spasmolytic And Calcium Antagonist Activities Of Nigella Sativa Seeds (Kalonji): A Traditional Herbal Product With Multiple Medicinal Uses, A H. Gilani, N Aziz, I M. Khurram, K S. Chaudhary, A Iqbal

Department of Biological & Biomedical Sciences

Objective: The seeds of Nigella sativa locally known as "Kalonji" has been used in traditional medicine for the treatment of a variety of diseases including diarrhoea and asthma. The crude extract of N. sativa seeds (Ns.Cr) was studied in vitro for its possible spasmolytic and bronchodilator activities to rationalize the folkloric uses.
Methods: Isolated rabbit jejunum and guinea-pig tracheal preparations were set up in Tyrode's and Kreb's solutions respectively and aerated with 5% CO2 in oxygen. Isotonic and isometric responses were measured on Bioscience oscillograph and Grass polygraph respectively.Results: The Ns.Cr caused a dose-dependent (0.1-3.0 mg/ml) relaxation of spontaneous contractions …

Pilot Mental Workload Calibration, Jeremy B. Noel

Theses and Dissertations

Predicting high pilot mental workload is important to the U.S. Air Force because lives and aircraft can be lost when errors are made during periods of mental overload and task saturation. Current research efforts use psychophysiological measures such as electroencephalography, cardiac, ocular, and respiration measures in an attempt to identify and predict mental workload levels. The primary focus of this effort is the development of a calibration scheme that allows a small subset of salient psychophysiological features developed using actual flight data for one pilot on a given day to accurately classify pilot mental workload for a separate pilot on …

Il-1Α And Tnf-Α Down-Regulate Crh Receptor-2 Mrna Expression In The Mouse Heart, Sarah C. Coste, Kurt A. Heldwein, Susan L. Stevens, Eric Tobar-Dupres, Mary P. Stenzel-Poore

Faculty Publications

Two receptors (CRH receptor type 1 and CRH receptor type 2) have been identified for the stress-induced neuropeptide, CRH and related peptides, urocortin, and urocortin II. We previously found marked down-regulation of cardiac CRH receptor type 2 expression following administration of bacterial endotoxin, lipopolysaccharide, a model of systemic immune activation, and inflammation. We postulated that inflammatory cytokines may regulate CRH receptor type 2. We show that systemic IL-1α administration significantly down-regulates CRH receptor type 2 mRNA in mouse heart. In addition, TNFα treatment also reduces CRH receptor type 2 mRNA expression, although the effect was not as marked as with …

Spontaneous And Induced Genetic Mutations Of The Pomc System, James L. Smart, Malcolm J. Low

Faculty Publications - Department of Biological & Molecular Science

No abstract provided.

Entropy Generation Method To Quantify Thermal Comfort, S. C. Boregowda, S. N. Tiwari, S. K. Chaturvedi

Mechanical & Aerospace Engineering Faculty Publications

The present paper presents a thermodynamic approach to assess the quality of human-thermal environment interaction and quantify thermal comfort. The approach involves development of entropy generation term by applying second law of thermodynamics to the combined human-environment system. The entropy generation term combines both human thermal physiological responses and thermal environmental variables to provide an objective measure of thermal comfort. The original concepts and definitions form the basis for establishing the mathematical relationship between thermal comfort and entropy generation term. As a result of logic and deterministic approach, an Objective Thermal Comfort Index (OTCI) is defined and established as a …

The Effects Of Strength Training On The Bone Mineral Density Of Aerobically Trained Perimenopausal Women, Jill Marie Kowalski

Masters Theses

The purpose of this study was to determine if a strength training program has an effect on the bone mineral density of aerobically trained perimenopausal women. The study also hoped to determine if high intensity strength training with low repetitions will result in a greater increase in bone density as compared with low intensity strength training with high repetitions. The duration of the study was six months.

The participants were twenty-five aerobically trained perimenopausal female volunteers. They were randomly selected to be in one of three groups. Group 1 was the aerobic control where the participants continued with their aerobic …

Impaired Fast-Spiking, Suppressed Cortical Inhibition, And Increased Susceptibility To Seizures In Mice Lacking Kv3.2 K+ Channel Proteins, David Lau, Eleazar Vega-Saenz De Miera, Diego Contreras, Alan Chow, Richard Paylor, Christopher S. Leonard, Bernardo Rudy

NYMC Faculty Publications

Voltage-gated K(+) channels of the Kv3 subfamily have unusual electrophysiological properties, including activation at very depolarized voltages (positive to -10 mV) and very fast deactivation rates, suggesting special roles in neuronal excitability. In the brain, Kv3 channels are prominently expressed in select neuronal populations, which include fast-spiking (FS) GABAergic interneurons of the neocortex, hippocampus, and caudate, as well as other high-frequency firing neurons. Although evidence points to a key role in high-frequency firing, a definitive understanding of the function of these channels has been hampered by a lack of selective pharmacological tools. We therefore generated mouse lines in which one …

The Roles Of Ca2+ And Camp In The Nematocyst Discharge Of The Sea Anemone Tentacle, Veysel Haktan Ozacmak

Loma Linda University Electronic Theses, Dissertations & Projects

The phylum Cnidarians are aquatic animals, including jellyfish, hydra, sea anemones, and corals. They are the simplest metazoans having a nervous system and are diploblastic. Cnidarians are obligate predators that capture prey using specialized stinging cells called cnidocytes. The cnidocyte contains a nematocyst, which is a capsule containing an inverted, hollow tubule. Prey contacting the tentacle triggers the nematocyst tubule to rapidly evert; a process called discharge. The everting tubule penetrates and envenomates the prey, which is carried to the mouth by tentacle movements.

Generally both chemical and mechanical stimuli are needed to trigger discharge. The cnidocytes, in sea anemones, …

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 …

Method And Apparatus For Adaptive Filtering By Counting Acoustic Sample Zeroes In Ultrasound Imaging, Gregory R. Bashford, Edward D. Nonnweiler, David D. Becker, David John Muzilla

Biomedical Imaging and Biosignal Analysis Laboratory

An ultrasound imaging system having an adaptive spatial filter the filter coefficients of which, for particular image parameter sample, are determined by counting the number of neighboring image parameter samples having zero or near-zero values. If the number of zero or near-zero values in a data window is greater than a predetermined threshold, the data in the window is passed, not filtered. This filter has two advantages over other spatial filters. First, image parameter data samples having only zero or near-zero neighboring values (i.e., isolated "point noise") are not smeared. Second, boundaries such as the edge of color in a …

Interactions Of Igf-Ii And Cathepsin D In Mcf-7 Breast Cancer Cells, Jesika S. Faridi

Loma Linda University Electronic Theses, Dissertations & Projects

A primary role of the IGF-II/M6P receptor is to target lysosomal enzymes from the golgi to the lysosomes. This receptor has distinct binding sites for IGF-II and M6P, however, reciprocal interactions between these ligands have been observed (Kiess et al. 1989, 1990). Since IGF-II modulates the routing of cathepsin D in MCF-7 cells by blocking the intracellular binding of cathepsin D to the IGF-II/M6P receptor (De León et al. 1996), we hypothesized that expressing a mutant form of IGF-II that does not bind the IGF-II/M6P receptor will not interfere with lysosomal enzyme trafficking.

In our present study, we report the …

The Affect Of Low Intensity, Progressive, Aerobic Exercise Training On Cardiovascular Function In The Diabetic Rat, Steven Michael Bauer

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Masters of Science in Biology by Steven Michael Bauer on August 4, 2000.

Direct Determination Of The Kinetics Of Oxygen Diffusion To The Photocytes Of A Bioluminescent Elaterid Larva, Measurement Of Gas- And Aqueous-Phase Diffusional Barriers And Modelling Of Oxygen Supply, G. S. Timmins, E. J. Bechara, H. M. Swartz

Dartmouth Scholarship

We describe the development and use of a direct kinetic technique to determine the time taken for oxygen to diffuse from the external environment into the light-producing cells (photocytes) in the prothorax of bioluminescent larvae of Pyrearinus termitilluminans. This was achieved by measuring the time course of the pseudoflash induced through sequential anoxia followed by normoxia. We have also determined the separate times taken for this oxygen diffusion in gaseous and tissue (predominantly aqueous) phases by using helium and nitrogen as the carrier gas. Of the total time taken for diffusion, that in the gas phase required 613+/-136 ms (mean …

Role Of Lipolysis And Lipogenesis In The Development Of Diet-Induced Obesity, Michael John Davies

Theses and Dissertations in Biomedical Sciences

Obesity is an increasingly common public health problem with approximately one-half of the American adult population overweight and one-quarter considered obese. This alarming trend has led researchers to determine potential causative factors of excess weight gain in humans. However, it is difficult to discern whether perturbations that result in obesity are the cause or simply the result of the obese state. Diet-induced obesity is one of the animal models that allow researchers to address temporal issues. Our laboratory utilizes a diet-induced obesity model in which Sprague-Dawley rats are placed on a purified moderately high fat diet and ultimately diverge into …

A New Submaximal Bicycle Protocol For The Estimation Of Vo₂Max, Anna R. Bennett

Human Movement Studies & Special Education Theses & Dissertations

Simple, valid, and accurate means for estimating aerobic capacity from submaximal cycle ergometry are needed for use with the general public. Current popular methods such as the ACSM cycle ergometer protocol have been shown to overestimate maximal oxygen uptake (VO₂max) by as much as 26%. In the current study, VO₂max was estimated using a new protocol based on a single 6-min stage designed to elicit 70% HRR. The data was also used to estimate VO₂max by the Astrand method for comparison. Forty-nine healthy males and females, aged 18-44 yr (X = 26 ± …

An Ultrastructural Survey Of The Nuchal Glands Of Rhabdophis Tigrinus (Serpentes: Colubridae), Kathleen A. Roberts

Biological Sciences Theses & Dissertations

Rhabdophis tigrinus, an Asian natricine snake, possesses a series of integumentary glands located in the nuchal skin. Previous studies indicated that the nuchal glands are of mesodermal origin, contain cardiac steroids analogous to bufotoxins found in the parotoid glands of toads, which are included in the snake's diet. The nuchal glands are defensive in function. Preliminary histological studies revealed differences in quality of the gland tissue compared to previous studies, and difference in fixation techniques were suspected. Seven specimens of R. tigrinus were fixed by perfusion using a conservative fixation process standard for electron microscopy. The nuchal gland series …

Method And Apparatus For Controlling Acoustic Signal Bandwidth In An Ultrasonic Diagnostic Imaging System, Jeffrey R. Resnick, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

An ultrasonic imaging system includes a receive beamformer that generates analog receive signals and a scan converter. A receive signal processing path interconnects the receive beamformer and the scan converter, and this processing path included both an A/D converter characterized by a selectable sampling rate and at least one filter characterized by at least one filter parameter. The filter parameter is selected as a function of the sampling rate to provide enhanced image quality.

Expression And Requirement Of Epithelial Fatty Acid- Binding Protein In Neuronal Axon Growth, Gregory William Allen

Loma Linda University Electronic Theses, Dissertations & Projects

Epithelial fatty acid-binding protein (E-FABP) is expressed in the dorsal root ganglia following sciatic nerve injury and in migrating and differentiating neurons during neuronal development. It was hypothesized that E-FABP expression is required for the robust outgrowth of axons from developing and regenerating neurons. To test this hypothesis, E-FABP expression in both PC12 cells and primary retinal neurons was examined. In PC12 cells, NGF induces E-FABP mRNA and protein during the period of neurite outgrowth, and E-FABP localizes to the perinuclear cytoplasm, nucleus, and growth cone. Furthermore, E-FABP-deficient cell lines exposed to NGF were less differentiated and had shorter neurites …

Molecular Cloning Of The Cdna For Porcine Parotid Hormone, Qian Zhang

Loma Linda University Electronic Theses, Dissertations & Projects

It has been found that parotid glands secrete a factor into blood that stimulates dentinal fluid movement, which in turn, prevents the development of dental caries. This factor, designated as parotid hormone, has been isolated from porcine parotid glands and its partial amino acid sequence has been determined. This study was developed to isolate and identify the cDNA sequence for porcine parotid hormone.

A porcine parotid cDNA library was constructed and hybridized with oligo probes designed based on the partial amino acid sequences of the isolated porcine parotid hormone. Over 100 positive clones were isolated and the complete nucleotide sequences …

First Principles Of Physio-Informatic Systems: Neurocosmology, David Jay Warner

Loma Linda University Electronic Theses, Dissertations & Projects

Physio-informatics is a new systems model for linking human physiologic systems to information systems in the most general way. Physio-informatics is used here to denote a systems based, physiologically robust reference architecture for designing and refining interactive human-computer interface systems in ways that increase operational throughput of information. In this dissertation, a systems model for interactive human-computer interface systems is developed. This model is a physiologically based reference architecture for designing and developing interactive human computer interface systems to match the human nervous system’s ability to transduce, transmit, and render to consciousness the necessary information to interact intelligently with information. …

Method And Apparatus For Three-Dimensional Ultrasound Imaging Of Biopsy Needle, Syed Omar Ishrak, Mir Said Seyed-Bolorforosh, William Thomas Hatfield, Todd Michael Tillman, Brian Peter Geiser, Gregory R. Bashford, Michael Joseph Washburn

Biomedical Imaging and Biosignal Analysis Laboratory

A method and an apparatus for three-dimensional ultrasound imaging of a needle-like instrument, such as a biopsy needle, inserted in a human body. The instrument is visualized by transmitting ultrasound beams toward the instrument and then detecting the echo signals using a linear array of transducer elements. The problem of ultrasound being reflected from a biopsy needle in a direction away from the transducer array is solved by steering the transmitted ultrasound beams t increase the angle at which the beams impinge upon the biopsy needle. Ideally the ultrasound beams are perpendicular to the needle. This increases the system's sensitivity …

Functional Characterization Of Mitogen-Dependent And Self-Perpetuating Nb2 Lymphoma Cell Lines, Charlotte Cockrell

Theses and Dissertations

This investigation involved the functional characterization of four Nb2 sub lines (Nb2-U- 17, Nb2-l l , SFJCD l , and D5) for their mitogenic and apoptotic responses to DEX ± PRL treatment. Many protein factors have been implicated to be crucial in controlling the apoptotic and mitogenic pathways. In conjunction with functional studies, an immunocytochemical investigation of four protein signals (NFKB, IKBa, STAT 5b, and the GR) was undertaken in an attempt to establish a relationship between the functional responsiveness of a given cell line and the concentration of a particular protein marker. Comparison of the functional data obtained for …

The Effect Of Two States Of Hydration On Muscular Endurance In Men, Melissa L. Petrucci

Masters Theses

The purpose of this study was to investigate the effects of two states of hydration has an effect on muscular endurance in men. Two groups of four men randomly assigned to each group participated in both states of hydration. Both groups were tested at baseline for height, weight, intra- and extra-cellular water, total body water, and a one-repetition maximum strength test. Subjects were then tested after a 24 hour period of water deprivation, and after a 24 hour period of normal water intake (8 ten oz glasses of water). A urine specific gravity test, intra- and extra-cellular water, total body …

Client-Centered Versus Traditional-Directive Educational Approach: A Randomized Study Of Exercises And Perceived Control Among Patients With Type 2 Diabetes, Melissa D. Olfert

Loma Linda University Electronic Theses, Dissertations & Projects

A patient’s adherence to self-management therapies in diabetes strongly influences health outcomes, health care utilization, and ultimately health care costs. Engaging in regular exercise therapy reduces risk factors associated with type 2 diabetes. The purpose of this randomized prospective study was to determine if a client-centered approach (CCA) toward diabetes education, verses a traditional-directive approach (TDA), would improve exercise participation, perceived control, intention to exercise, and glycemic control in patients with type 2 diabetes.

Fifty-nine type 2 patients were randomized into two groups: CCA and TDA. Diabetes education in the CCA group provided empowerment toward acquiring knowledge, skills, and responsibility …

Recycling Of Deuterium From Dideuterated Glucose During Moderate Exercise, Michael A. Horning, Sheri R. Colberg, Gretchen A. Casazza, George A. Brooks

Educational Leadership & Workforce Development Faculty Publications

A doubly labelled tracer molecule of glucose, [6,6^-2HJglucose, has been used to measure the rate of glucose appearance in blood due to endogenous glucose production (by the liver and kidneysj.^l,2 Considered 'non-recirculating', this tracer generally provides a realistic estimate of glucose kinetics.^2,3 Used as a dual tracer in conjunction with [l-¹³C]glucose, the extent of glucose recycling can be quantitated.^2-4 but the extent of possible recirculation of a single deuterium atom on newly formed glucose must then be considered.

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 …

A Pdz-Interacting Domain In Cftr Is An Apical Membrane Polarization Signal, Bryan D. Moyer, Jerod Denton, Katherine H. Karlson, Donna Reynolds, Shusheng Wang, John E. Mickle, Michael Milewski, Garry R. Cutting, William B. Guggino, Min Li, Bruce A. Stanton

Dartmouth Scholarship

Polarization of the cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP-activated chloride channel, to the apical plasma membrane of epithelial cells is critical for vectorial transport of chloride in a variety of epithelia, including the airway, pancreas, intestine, and kidney. However, the motifs that localize CFTR to the apical membrane are unknown. We report that the last 3 amino acids in the COOH-terminus of CFTR (T-R-L) comprise a PDZ-interacting domain that is required for the polarization of CFTR to the apical plasma membrane in human airway and kidney epithelial cells. In addition, the CFTR mutant, S1455X, which lacks the 26 …

Method And Apparatus For Controlling Acoustic Signal Bandwidth In An Ultrasonic Diagnostic Imaging System, Jeffrey R. Resnick, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

An ultrasonic imaging system includes a receive beam former that generates analog receive signals and a scan converter. A receive signal processing path interconnects the receive beamformer and the scan converter, and this processing path includes both an A/D converter characterized by a selectable sampling rate and at least one filter characterized by at least one filter parameter. The filter parameter is selected as a function of the sampling rate to provide enhanced image quality.

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 …