The sport of triathlon has evolved to become a discipline comprising races of different lengths and formats. It has also undergone significant growth in popularity and exposure with several variations in format from the classic swim - bike - run combination attracting significant television and media coverage. Since 2021 an original and unique format called the Arena Games Triathlon (or in 2024 the E-Games) has evolved that involves athletes competing against each other in swimming, cycling and running combining both the real and virtual worlds in one race.
View Article and Find Full Text PDFJ Ayub Med Coll Abbottabad
December 2017
Background: The objectives of this study were to explore the effects of low dose of the nonionizing (REW) emitted by a mobile phone on the development of chick embryo.
Methods: one hundred and twenty chick fertilized eggs were equally divided into a control and an exposed group. Sixty fertilized eggs were placed in an egg incubator with a mobile phone (SAR US: 1.
Sultan Qaboos Univ Med J
August 2014
Objectives: Cystic fibrosis transmembrane conductance regulator (CFTR) mutations form distinct mutational panels in different populations and subgroups. The frequency of cystic fibrosis (CF) mutations and prevalence are unknown in Oman. This study aimed to elucidate the mutational panel and prevalence of CF for the North Al Batinah (NAB) region in Oman and to estimate the national prevalence of CF based on the carrier screening of unrelated volunteers.
View Article and Find Full Text PDFObjectives: Medical education requires student comprehension of both technical (scientific/medical) and non-technical (general) vocabulary. Our experience with "English as a second language" (ESL) Arab students suggested they often have problems comprehending scientific statements because of weaknesses in their understanding of non-scientific vocabulary. This study aimed to determine whether ESL students have difficulties with general vocabulary that could hinder their understanding of scientific/medical texts.
View Article and Find Full Text PDFNucleosides Nucleotides Nucleic Acids
April 2012
The aim of the study is the biochemical characterization of human DNA modified with arginine and peroxynitrite. In the present study, DNA was isolated from human blood cells and its adduct was formed with one of the amino acid, arginine. The DNA-arginine adduct was then modified with peroxynitrite, a reactive nitrogen species.
View Article and Find Full Text PDFSultan Qaboos Univ Med J
November 2011
Objectives: In order to increase their effectiveness, methods of teaching morphological sciences need to be revised to incorporate the recent technological advances made in the field of medicine. Teaching human structure with conventional methods of prosections using dissected cadaveric specimen alone quite often fails to prepare students adequately for their clinical training. A learner-oriented method, incorporating three dimensional spatial anatomy and more closely mirroring the clinical setting, is required.
View Article and Find Full Text PDFLoperamide (LOP) is a peripherally acting opioid receptor agonist used for the management of chronic diarrhea through the reduction of gut motility. The lack of central opioid effects is partly due to the efflux activity of the multidrug resistance transporter P-glycoprotein (P-gp) at the blood-brain barrier. The protease inhibitors are substrates for P-gp and have the potential to cause increased LOP levels in the brain.
View Article and Find Full Text PDFA whole-cell model of a macrophage (mphi) is developed to simulate pH and volume regulation during a NH4Cl prepulse challenge. The cell is assumed spherical, with a plasma membrane that separates the cytosolic and extracellular bathing media. The membrane contains background currents for Na+, K+ and Cl-, a Na(+)-K+ pump, a V-type H(+)-extruder (V-ATPase), and a leak pathway for NH4+.
View Article and Find Full Text PDFLung-lining fluid (LLF) is a primary constituent of the pulmonary host defense system. It is distributed continuously throughout the respiratory tract but is heterogeneous regarding its chemistry and physiology between the conducting airways and alveoli. The conducting airways are lined with airway surface liquid (ASL), a mucus gel-aqueous sol complex that interacts functionally with epithelial cilia as the mucociliary escalator.
View Article and Find Full Text PDFAn analytical model of V-type H+-translocating ATPase (V-ATPase) was developed based on an approximation to the mechanochemical model of Grabe et al. (Biophys. J.
View Article and Find Full Text PDFThe acid-base status and functional responses of alveolar macrophages (mphi) are influenced by the activity of plasmalemmal V-type H+-pump (V-ATPase), an electrogenic H+ extruder that provides a possible link between intracellular pH (pHi) and plasma membrane potential (Em). This study examined the relationships among Em, pHi, and plasmalemmal V-ATPase activity in resident alveolar mphi from rabbits. Em and pHi were measured using fluorescent probes.
View Article and Find Full Text PDFComp Biochem Physiol A Mol Integr Physiol
October 2003
Carbonic anhydrase (CA) catalyzes the interconversion of CO(2) and HCO(3)(-). Intracellular (extravascular) and intravascular (extracellular) CA has been identified and localized in the lungs of reptiles and mammals. Less information is known, however, on the presence of intravascular CA in the lungs of amphibians and avians.
View Article and Find Full Text PDFThe role of plasmalemmal V-type H+ translocating ATPase (V-ATPase) in regulation of intracellular pH (pHi) is unclear in monocytes. This study examined the plasmalemmal V-ATPase and Na+/H+ exchanger (NHE) in U937 human monocytes. The fluorescent probe 2',7'-biscarboxyethyl-5,6-carboxyfluorescein was used to monitor baseline pHi and the kinetics of pHi recovery from cytosolic acid-loads (NH4Cl prepulse).
View Article and Find Full Text PDFDisruption of cellular acid-base status alters the host defence functions of alveolar macrophages (m phi). These pH effects might be mediated by pH-sensitive changes in the signalling pathways of the effector functions of m phi. The present study examined the effects of intracellular pH (pH(i)) on the free cytosolic calcium concentration ([Ca(2+)](i)), an important second messenger for cell functions.
View Article and Find Full Text PDFComp Biochem Physiol A Mol Integr Physiol
September 2002
The distribution of plasmalemmal V-type H+-pumps (V-ATPase) among mammalian macrophages (mvarphi) is uncertain and, hence, the functional significance of mvarphi plasmalemmal V-ATPase is unclear. This study investigated the role of V-ATPase in the regulation of intracellular pH (pH(i)) by resident alveolar mvarphi from sheep, pigs, dogs and rabbits. The fluorescent probe 2',7'-biscarboxyethyl-5,6-carboxyfluorescein was used to monitor baseline pH(i) and the rate of pH(i) recovery (dpH(i)/dt) from intracellular acid-loads (NH(4)Cl prepulse).
View Article and Find Full Text PDFCellular acid-base status has been found to exert selective actions on the effector functions of activated macrophages (mphi). We examined the effects of extracellular pH (pH(o)) on the production of tumour necrosis factor-alpha (TNF-alpha) induced by lipopolysaccharide (LPS) in resident alveolar mphi. Cells were obtained by bronchoalveolar lavage of rabbits, activated in vitro with LPS, and cultured at pH(o) 5.
View Article and Find Full Text PDFThe present studies determined the effects of extracellular pH (pH(o)) on the production of tumour necrosis factor-alpha (TNF-alpha) in the macrophage-like cell lines RAW 246.7 and J774 A.1.
View Article and Find Full Text PDFJ Appl Physiol (1985)
October 2000
Changes in plasma volume in vivo cause rapid changes in extracellular pH by altering the plasma bicarbonate concentration at a constant Pco(2) (Garella S, Chang BS, and Kahn SI. Kidney Int 8: 279, 1975). Few studies have examined the possibility that changes in cell volume produce comparable changes in intracellular pH (pH(i)).
View Article and Find Full Text PDFBafilomycin A(1), a selective inhibitor of V-type H(+)-translocating ATPase (V-ATPase), may be a useful adjunct in cancer chemotherapy (Altan et al. [1998] J Exp Med 187:1583-1598). Therapeutic uses of the enzyme inhibitor need to consider the agent's potential effects on normal (nontumor) cells.
View Article and Find Full Text PDFThe differences between cytokine-producing profiles of activated macrophages (A-M phi) and suppressor macrophages (S-M phi) were examined. A-M phi, which exhibited cytotoxicity against RK-13 cells, were generated from resident rabbit alveolar M phi by treatment with lymphokine solution (culture fluids of rabbit spleen cells stimulated with concanavalin A [Con A]). S-M phi, which were able to inhibit cellular proliferations of rabbit spleen cells stimulated with Con A, were generated from resident alveolar M phi by treatment with 1-methyladenosine (an immunosuppressive molecule in tumourous ascites fluids).
View Article and Find Full Text PDFTurtles possess a significant postcapillary CO2 partial pressure (PCO2) disequilibrium between arterial blood and alveolar gas. There are several possible explanations for this blood disequilibrium including a slow rate of erythrocyte physiological anion shift (Cl-/HCO3- exchange) or inaccessibility of plasma HCO3- to red blood cell or pulmonary carbonic anhydrase. The present study characterized the contribution of erythrocyte anion exchange and pulmonary and erythrocyte carbonic anhydrase to CO2 excretion and, hence, to postcapillary CO2-HCO3--H+ equilibration in blood-perfused turtle (Pseudemys scripta) lungs.
View Article and Find Full Text PDFThe dose dependence and time course of smoke inhalation injury were determined in a rabbit model. Animals were insufflated with 18-90 breaths of cotton smoke or room air (control) at a rate of 18 breaths/min and tidal volume of 12 ml/kg. Smoke-exposed animals exhibited dose-related histologic effects with progressive deterioration of respiratory function during the postexposure period of observation (96 h).
View Article and Find Full Text PDFThe present study determined the effects of cotton smoke inhalation on the functioning of alveolar macrophages (mphi). Smoke inhalation led to dose-dependent impairment of respiratory gas exchange by 48 h postexposure and pulmonary edema by 96 h. Maximal effects were observed in animals ventilated with 54 breaths of cotton smoke (3-min exposure, 18 breaths/min).
View Article and Find Full Text PDFTo explore the feasibility and operating limits of arteriovenous extracorporeal CO2 removal (AVCO2R) for support of acute respiratory failure, the authors developed a mathematical model to simulate (AVCO2R), evaluate the effects of several parameters used in its application, and predict the feasibility and necessary conditions for total CO2 removal. The mathematical model incorporated compartments representing blood, pulmonary alveoli, pulmonary capillaries, peripheral tissues and capillaries, and an extracorporeal gas exchange device. The model was validated against an animal model of extracorporeal CO2 removal.
View Article and Find Full Text PDF