Physiology Commons^™

Influence Of Body Composition, Oral Contraceptive Use, And Physical Activity On Bone Mineral Density In Premenopausal Women, Vanessa D. Sherk†, Clint D. Howard†, Michael G. Bemben‡, Debra A. Bemben‡

International Journal of Exercise Science

In premenopausal women, low bone density may reflect attainment of a lower peak bone mass which can increase risk of osteoporosis after menopause. The purpose of this study was to examine the relationship between total body, lumbar spine, and proximal femur bone mineral density (BMD) and body composition and oral contraceptive (OC) use in 18-30 year old women. Sixty-five healthy women, split into groups of oral contraceptive users (OC, n = 36) and non oral contraceptive users (Non-OC, n = 29), completed Baecke physical activity, calcium intake, and menstrual history questionnaires. Total body, AP lumbar spine, and dual proximal femur …

Comparison Of Body Composition Measurements Using A New Caliper, Two Established Calipers, Hydrostatic Weighing, And Bodpod, Erin E. Talbert*, Michael G. Flynn‡, Jeffrey W. Bell†, Andres E. Carrillo†, Marquita D. Dill†, Christiania N. Christensen*, Colleen M. Thompson†

International Journal of Exercise Science

Purposes: (1) To compare the Lafayette Instruments (LI) skinfold caliper to the Lange (L) and Harpenden (H) calipers using a diverse subject population. (2) To determine the validity of the LI caliper in a subset of subjects by comparing body compositions from skinfold thicknesses to those measured by hydrostatic weighing (HW) and air displacement plethysmography (ADP). (3) To compare measurements obtained by experienced (EX) and inexperienced (IX) technicians using all three calipers. Methods: Skinfold measurements were performed by both EX and IX technicians using three different calipers on 21 younger (21.2 ± 1.5 yrs) and 20 older (59.2 ± 4 …

Timing Carbohydrate Beverage Intake During Prolonged Moderate Intensity Exercise Does Not Affect Cycling Performance, George G. Schweitzer†, John D. Smith‡, James D. Lecheminant‡

International Journal of Exercise Science

Carbohydrate beverages consumed during long-term exercise have been shown to attenuate fatigue and improve performance; however, the optimal timing of ingestion is unclear. Therefore, the purpose of this study was to determine if timing the carbohydrate ingestion (front-loading (FL), continual loading (CL), and end-loading (EL)) during prolonged exercise influenced exercise performance in competitive cyclists. Ten well-trained cyclists completed three separate exercise bouts on a bicycle ergometer, each lasting 2 hours at an intensity of ~67% VO₂ max, followed by a 15-minute “all out” time trial. In the FL trial, participants ingested a carbohydrate beverage during the first hour and …

From The Editors: Assessing The International Journal Of Exercise Science After One Year, T. Scott Lyons, James W. Navalta

International Journal of Exercise Science

Western Kentucky University (WKU) strives to be a “leading American university with international reach.” In an effort to contribute to that mission, Drs. Scott Lyons and James Navalta of the Exercise Science program endeavored in 2007 to start a student-focused, on-line journal. Working closely with Berkeley Press, the platform for the International Journal of Exercise Science (IJES) was established during the summer of 2007 and it went “live” in January 2008. The journal has now been on-line for over one year and has enjoyed great success, with quality research submitted from graduate and undergraduate students, as well as professionals. We …

Adaptation Of The Bacterial Membrane To Changing Environments Using Aminoacylated Phospholipids, Hervé Roy, Kiley Dare, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Fine‐tuning of the biophysical properties of biological membranes is essential for adaptation of cells to changing environments. For instance, to lower the negative charge of the lipid bilayer, certain bacteria add lysine to phosphatidylglycerol (PG) converting the net negative charge of PG (−1) to a net positive charge in Lys‐PG (+1). Reducing the net negative charge of the bacterial cell wall is a common strategy used by bacteria to resist cationic antimicrobial peptides (CAMPs) secreted by other microbes or produced by the innate immune system of a host organism. The article by Klein et al. in the current issue of …

Resolving The Lateral Component Of Blood Flow Velocity Based On Ultrasound Speckle Size Change With Scan Direction And Speed, Tiantian Xu, Greg R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Conventional blood flow velocity measurement using ultrasound is capable of resolving the axial component (i.e., that aligned with the ultrasound propagation direction) of the blood flow velocity vector. However, these Doppler-based methods are incapable of detecting blood flow in the direction normal to the ultrasound beam. In addition, these methods require repeated pulse-echo interrogation at the same spatial location. In this paper, we introduce a method which estimates the lateral component of blood flow within a single image frame using the observation that the speckle pattern corresponding to the blood reflectors (typically red blood cells) stretches (i.e., is “smeared”) if …

Further Progress On Lateral Flow Estimation Using Speckle Size Variation With Scan Direction, Tiantian Xu, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Conventional blood flow velocity measurement using ultrasound is capable of resolving the axial component (i.e., that aligned with the ultrasound propagation direction) of the blood flow velocity vector. However, these Doppler-based methods are incapable of detecting blood flow in the direction normal to the ultrasound beam. In addition, these methods require repeated pulse-echo interrogation at the same spatial location. In this paper, we report additional data on a new method recently introduced. This method estimates the lateral component of blood flow within a single image frame using the observation that the speckle pattern corresponding to the blood reflectors (typically red …

Single Molecule Diffusion Coefficient Estimation By Image Analysis Of Simulated Ccd Images To Aid High-Throughput Screening, Pengfei Song, Lloyd M. Davis, Greg Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Extension of one-dimensional signal analysis to two-dimensional image analysis could accelerate conventional methods of high-throughput screening in the discovery of new pharmaceutical agents. This work describes a first step taken towards this goal – the evaluation of image-analysis based estimation strategies of the diffusion coefficient of a single molecule transported within a microfabricated flowcell. A computer simulation of single-molecule imaging by a charge-coupled device (CCD) camera is used to determine if it is possible to distinguish three different types of molecules with different diffusion coefficients. The Gaussian fitting algorithm finds the variance of the transverse trajectory, which increases linearly with …

Optimal Thresholds Of Feature Tracking For Blood Velocity And Tissue Motion Estimation, Tiantian Xu, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Feature tracking is an algorithm for estimating blood flow velocity and tissue motion using pulse-echo ultrasound. In contrast to cross-correlation speckle-tracking techniques, feature tracking identifies features at discrete locations and corresponds them from frame to frame. Prior studies have demonstrated that feature-tracking estimates exhibit lower variance than those obtained by the conventional autocorrelation method and require less computational complexity than either speckle tracking or autocorrelation. To date, not much attention has been paid to the process by which trackable features (normally local maxima) are selected from the set of all available features. In the selection process, it is desired to …

Characterization Of 24 Microsatellite Loci In Delta Smelt, Hypomesus Transpacificus, And Their Cross-Species Amplification In Two Other Smelt Species Of The Osmeridae Family, Kathleen M. Fisch, Jessica Lynn Petersen, Melinda R. Baerwald, John K. Pedroia, Bernie May

Department of Animal Science: Faculty Publications

We characterized 24 polymorphic tetranucleotide microsatellite loci for delta smelt (Hypomesus transpacificus) endemic to the San Francisco Bay Estuary, California, USA. Screening of samples (n = 30) yielded two to 26 alleles per locus with observed levels of heterozygosity ranging from 0.17 to 1.0. Only one locus deviated from Hardy–Weinberg equilibrium, suggesting these individuals originate from a single panmictic population. Linkage disequilibrium was found in two pairs of loci after excluding the locus out of Hardy–Weinberg equilibrium. Twenty-two primer pairs cross-amplified in wakasagi smelt (Hypomesus nipponensis), and 15 primer pairs cross-amplified in longfin smelt ( …

The Increase In Renal Sodium Excretion In Response To Angiotensin Ii Infusion In Exercised Female Rats Is Dependent On A Rise In Renal Perfusion Pressure, Karmon Janssen

All Graduate Theses, Dissertations, and Other Capstone Projects

Prior studies in this lab have shown that chronically exercised female spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats excrete a greater amount of sodium in response to angiotensin II (Ang II) infusion than do sedentary rats. The current study determined if the difference in renal sodium excretion persisted when the renal perfusion pressure (RPP) was held constant. Female SHR and female WKY rats were separated into sedentary and exercised groups at 4 weeks of age. The exercise group voluntarily exercised for at least eight weeks using an exercise wheel and time/distance monitor. At 13 weeks of age or older, …

The Effect Of A Commercially Available Caffeine Based Dietary Supplement On 40-Kilometer Time Trial Performance, Lee A. Weidauer

Electronic Theses and Dissertations

Purpose: To determine wheather ot not the nutritional supplement PreRace containing L-Taurine, Citrulline Malate, Quercetin, DiMethyl Amino Ethanol, Caffeine, Metabromine, Catechin, and Malic acid will improve performance in an indoor 40 Kilometer cycling time trial.
Methods: Seven male cyclists ages 21-58 participated in a placebo-controlled investigation which consisted of two trials in which they consumed either the supplement PreRace or aloe vera juice. In each of the trials the placebo or supplement was mixed with a sports beverage. Subjects performed a 40 kilometer time trial and measurements of oxygen consumption and lactate were taken every 15 minutes as well as …

Mice Deficient In The Serine/Threonine Protein Kinase Vrk1 Are Infertile Due To A Progressive Loss Of Spermatogonia, Matthew S. Wiebe, R. Jeremy Nichols, Tyler P. Molitor, Jill K. Lindgren, Paula Traktman

Nebraska Center for Virology: Faculty Publications

The VRK1 protein kinase has been implicated as a proproliferative factor. Genetic analyses of mutant alleles of the Drosophila and Caenorhabditis elegans VRK1 homologs have revealed phenotypes ranging from embryonic lethality to mitotic and meiotic defects with resultant sterility. Herein, we describe the first genetic analysis of murine VRK1. Two lines of mice containing distinct gene-trap integrations into the Vrk1 locus were established. Insertion into intron 12 (GT12) spared VRK1 function, enabling the examination of VRK1 expression in situ. Insertion into intron 3 (GT3) disrupted VRK1 function, but incomplete splicing to the gene trap rendered this allele hypomorphic (~15% of …

Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia

Master's Theses (2009 -)

Coarctation of the aorta (CoA) is a major congenital heart disease, characterized by a severe stenosis of the proximal descending thoracic aorta. Traditionally, surgery has been the treatment of choice for CoA. Dacron patch aortoplasty gained increased popularity after its introduction in the mid-twentieth century due to its advantages over other surgical treatment methods available at the time. A major complication with Dacron patch aortoplasty has been the formation of late aneurysm with as much as 51% incidence reported in follow up studies. The change in aortic morphology and formation of aneurysms after Dacron patch surgery could lead to local …

Integrated Responses Of Crustaceans Inhabiting Estuaries To The Challenges Of Feeding And Digestion In Low Salinity, Daniel Luke Curtis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Estuaries are highly productive and serve as vital habitats for numerous decapod crustacean species. However, the environmental conditions within estuaries are often highly dynamic and subject to large changes in salinity and temperature that occur on seasonal and tidal scales. Not all of the species occupying these habitats are adept in coping with changes in these environmental conditions. This dissertation describes the influence of low salinity conditions on the 1) habitat preference, 2) feeding behaviour and 3) digestive physiology of crustaceans inhabiting estuaries. I have primarily focussed on a weak osmoregulator, the Dungeness crab, Cancer magister , but have also …

Adrenergic Receptor Expression On Raw264.7 Macrophages, Lindsay Ward

Honors Theses

In this study, AR surface expression patterns and regulation via AR-catecholamine interactions were characterized. Macrophage function was shown to be regulated by catecholamines through both Alpha- and Beta-ARs, as evidenced by corresponding alterations in cytokine production. Treatment of activated macrophages with NE, a general catecholamine, or fomoterol, a P-AR agonist, produced significant decreases in TNF and IL-6 secretion. The effecis of clonidine, an Alpha-AR agonist, produced less consistent results, but clonidine-mediated enhancement of cytokine secretion appears to be mediated by Alpha-AR signaling. LPS was shown to noticeably change the surface expression ofboth types of ARs in RAW264.7 macrophages. However, NE …

The Role Of Nucleotide Signaling In The Regulation Of Icl,Swell In Human 1321n1 Astrocytoma Cells, Ian C. Wenker

Browse all Theses and Dissertations

Swollen cells expel osmolytes to decrease volume in a process referred to as Regulatory Volume Decrease, or RVD. The plasma membrane current ICl,swell is ubiquitously expressed in mammalian cells and contributes significantly to RVD. In a variety of cell types, activation of ICl,swell is enhanced by nucleotide signaling. In this study, we used human astrocytoma cells to examine whether nucleotide signaling is necessary or sufficient for ICl,swell activation. Three clones of the 1321N1 human astrocytoma cell line were used for voltage clamp recordings. One clone was transfected with P2Y1 receptors, another with P2Y2 receptors and a third was devoid of …

Clamping Of Intracellular Ph In Neurons From Neonatal Rat Brainstem During Hypercapnia, Vivian C. Nanagas

Browse all Theses and Dissertations

In this work, I have made attempts to clamp intracellular pH in the presence of hypercapnic acidosis (HA) in neurons from the locus coeruleus (LC) and nucleus of the solitary tract (NTS) in neonatal rat (ages P3 to P17) brainstem slices. Two approaches were used to minimize hypercapnia-induced ΔpH_i: 1) an increase in intracellular buffering power with a high HEPES concentration using whole cell patching techniques in individual neurons, and 2) a weak acid diffusion technique that relies on an efflux of weak acid to counterbalance HA influx thereby clamping pH_i in multiple neurons at once. pH …

Comparisons Of Cubed Ice, Crushed Ice, And Wetted Ice On Intramuscular And Surface Temperature Changes, Joseph H. Dykstra, Holly M. Hill, Michael G. Miller, Christopher C. Cheatham

University Faculty Publications and Creative Works

Context: Many researchers have investigated the effectiveness of different types of cold application, including cold whirlpools, ice packs, and chemical packs. However, few have investigated the effectiveness of different types of ice used in ice packs, even though ice is one of the most common forms of cold application. Objective: To evaluate and compare the cooling effectiveness of ice packs made with cubed, crushed, and wetted ice on intramuscular and skin surface temperatures. Design: Repeated-measures counterbalanced design. Setting: Human performance research laboratory. Patients or Other Participants: Twelve healthy participants (6 men, 6 women) with no history of musculoskeletal disease and …

Effects Of Metal Protoporphyrins On Burn Wound Conversion, Katie Braun

Theses and Dissertations

A murine model was utilized to test the influence of heavy metal protoporphyrins on burn conversion, heme oxygenase – 1 (HO-1) expression, and inflammation. Heavy metal protoporphyrins, such as cobalt protoporphyrin (Co PP) and tin protoporphyrin (Sn PP), were used to influence the heme oxygenase activity. The effects of these heavy metal protoporphyrins on burn wound conversion were examined using a burn comb model in rats. In addition to assessing the extent of conversion, HO-1 expression and parameters of inflammation were also examined in the area of injury (interspace region) subject to conversion. These studies demonstrate proof in principal that …

Effects Of Light Exposure On The Release Of Oxygen From Hemoglobin In A Red Blood Cell Suspension, Tanikka Toler

Theses and Dissertations

The main function of the cardiovascular system is to deliver a sufficient quantity of oxygenated blood to the tissues, cells, and organs of the body in order to provide the cells with essential nutrients for metabolism and for the removal of waste products. All cells require and utilize oxygen. Oxygen is transported to various cells and tissues via red blood cells flowing through the microcirculation of an organism. Measurement of oxygen transport in the microcirculation has shown that about ten times more oxygen appears to leave the blood of arterioles than can be accounted for by diffusion. One possibility to …

The Effects Of Excess Corticosterone On Lkb1 And Ampk Signaling In Skeletal Muscle Of Rats, Gary N. Nakken

Theses and Dissertations

Cushing's syndrome and glucocorticoid therapy lead to central obesity, insulin resistance, and symptoms of altered energy regulation similar to those observed in the metabolic syndrome. We hypothesized that excess glucocorticoids alter energy sensing/signaling in skeletal muscle through mediation of the LKB1/AMPK signaling pathway. To test this hypothesis, three 100 mg pellets of corticosterone were implanted subcutaneously in each of nine rats for two weeks. Responses were compared with sham operated controls fed ad libitum or food restricted to produce the body weights similar to the treatment group rats. After the treatment period, animals were anesthetized and the right gastrocnemius-plantaris and …

Co-Administration Of Sildenafil Potentiates Doxorubicin-Induced Apoptosis In Prostate Cancer: The Role Of Nf-Kappab, Sarah Hassanieh

Theses and Dissertations

Our recent studies have shown that that erectile dysfunction (ED) drugs including Sildenafil (Viagra), Vardenafil (Levitra) and Tadalafil (Cialis) enhance killing of several types of cancer cells by anticancer drug, Doxorubicin (DOX). We observed increased cell death by apoptosis in response to the combined treatment with ED drugs and DOX. However, the mechanism of such enhancement of cell death by combined treatment of ED drugs and DOX is not fully understood. Nuclear factor-κB (NF-κB) is an oxidant-sensitive transcription factor that plays a critical role in the immediate-early activation of a multitude of genes that have been documented to play critical …

Acute Effects Of Whole-Body Vibration On Lower Extremity Muscle Performance In Persons With Multiple Sclerosis, Kurt Jackson, Harold L. Merriman, Paul M. Vanderburgh, C. Jayne Brahler

Health and Sport Science Faculty Publications

Background and Purpose: Whole-body vibration (WBV) is a relatively new form of exercise training that may influence muscle performance. This study investigated the acute effects of high (26 Hz) and low (2 Hz) frequency WBV on isometric muscle torque of the quadriceps and hamstrings in persons with multiple sclerosis (MS).

Participants and Method: Fifteen individuals (mean age = 54.6 years, SD = 9.6) with MS and Expanded Disability Status Scale (EDSS) scores ranging from 0-6.5 (mean = 4.2, SD = 2.3) participated in this randomized cross-over study. Following baseline measures of isometric quadricep and hamstring torque, subjects were exposed to …

The Effects Of A 40mg Lasik Treatment On The Threshold Frequency Of Electrically Induced Muscle Cramps, Sara F. Bergeron

All-Inclusive List of Electronic Theses and Dissertations

Context: Muscle cramps that are caused by exercise can be painful and debilitating to an active individual. One theory to explain the cause of exerciseassociated muscle cramps is dehydration. While dehydration is a popular theory it has 111 yet to be studied as a sole factor to the incidence of muscle cramps. Objective: To examine the effect of mild dehydration on the threshold frequency (TF) of electrically induced muscle cramps (EIMC) in the flexor hallucis brevis.

Successful Implementation Of Inquiry-Based Physiology Laboratories In Undergraduate Major And Nonmajor Courses, Giovanni Casotti, Loretta Rieser-Danner, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.

Buccal Bone Changes Following Rapid Maxillary Expansion (Rmf), Long-Term Results, Elena S. Iacob

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to use Cone Beam Computed Tomography (CBCT) images to quantitatively evaluate buccal bone changes of maxillary first premolar (P1), second premolar (P2) and first molar (M1) shortly after Rapid Maxillary Expansion (RME) and at the end of orthodontic treatment, as well as to evaluate the variables that may be associated with the short-term and long-term changes. Forty-seven consecutive patients (25 males and 22 females) with a mean age of 14.5years and who required RME as part of their orthodontic treatment and had pre-RME (T1) and post-RME (T2) CBCT images available were used for the …

Female Collegiate Gymnasts And Experiences In Sport Retirement Due To Injury, Coleen Harrington Barry

Dissertations

There has been very limited research on sport retirement concerning the experiences that female collegiate athletes face when retiring from a sport due to injury. The purpose of this qualitative study was to explore, understand, and describe experiences that former NCAA Division I female gymnasts had when they retired from gymnastics, part-way through college, due to injury. The main objective of the study was to attempt to understand female collegiate gymnasts' sport retirement experiences and the impact these experiences may have had on their identity development and college experience. The study also considered female collegiate gymnasts' perceived needs and coping …

Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell

Faculty Publications

High dietary intake of selenium or isoflavones reduces risk factors for prostate cancer. We tested whether combined supplementation of these two dietary components would reduce prostate cancer risk factors in rats more than supplementation of each component individually. Methods Male Noble rat pups were exposed from conception to diets containing an adequate (0.33-0.45 mg/kg diet) or high (3.33-3.45 mg/kg) concentration of selenium as Se-methylselenocysteine and a low (10 mg/kg) or high (600 mg/kg) level of isoflavones in a 2 x 2 factorial design. Pups consumed their respective diets until sacrifice at 35, 100, or 200 days. Male Noble rat breeders, …

Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

As aquatic adults, eastern red-spotted newts (Notophthalmus v. viridescens) are generally green with two rows of dorsal spots, which vary in number between individuals and range in colour from orange to red. The function of these spots is unknown, but it is possible that they serve as sexual ornamentations and we examined this hypothesis by testing for sexual dimorphism in spot characteristics. We used an image analysis approach that has been used previously with this and other amphibian species to compare the number, size and colour – redness (hue score) and brightness – of spots in 100 male …