Science.gov

Sample records for 10-13 cm3 molecule-1

  1. 49 CFR 10.13 - Privacy Officer.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 1 2014-10-01 2014-10-01 false Privacy Officer. 10.13 Section 10.13... INDIVIDUALS General § 10.13 Privacy Officer. (a) To assist with implementation, evaluation, and administration issues, the Chief Information Officer appoints a principal coordinating official with the title...

  2. 49 CFR 10.13 - Privacy Officer.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Privacy Officer. 10.13 Section 10.13... INDIVIDUALS General § 10.13 Privacy Officer. (a) To assist with implementation, evaluation, and administration issues, the Chief Information Officer appoints a principal coordinating official with the title...

  3. 49 CFR 10.13 - Privacy Officer.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Privacy Officer. 10.13 Section 10.13... INDIVIDUALS General § 10.13 Privacy Officer. (a) To assist with implementation, evaluation, and administration issues, the Chief Information Officer appoints a principal coordinating official with the title...

  4. 49 CFR 10.13 - Privacy Officer.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Privacy Officer. 10.13 Section 10.13... INDIVIDUALS General § 10.13 Privacy Officer. (a) To assist with implementation, evaluation, and administration issues, the Chief Information Officer appoints a principal coordinating official with the title...

  5. 49 CFR 10.13 - Privacy Officer.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Privacy Officer. 10.13 Section 10.13... INDIVIDUALS General § 10.13 Privacy Officer. (a) To assist with implementation, evaluation, and administration issues, the Chief Information Officer appoints a principal coordinating official with the title...

  6. 44 CFR 10.13 - Emergencies.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Emergencies. 10.13 Section 10.13 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND... event of an emergency, the Regional Administrator may be required to take immediate action...

  7. Adaptation of California Measure of Mental Motivation-CM3

    ERIC Educational Resources Information Center

    Özdemir, Hasan Fehmi; Demirtasli, Nükhet Çikrikçi

    2015-01-01

    Education without doubt, plays a vital role for individuals to gain the essential personal traits of the 21st century, also known as "knowledge age". One of the most important skills among these fundamental qualities which the individuals should be equipped with is critical thinking. California Measure of Mental Motivation-CM3 was…

  8. 43 CFR 10.13 - Future applicability.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.13 Future applicability. (a) General. This section sets forth the applicability of the Act to museums and Federal agencies after expiration of the statutory deadlines...

  9. 43 CFR 10.13 - Future applicability.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.13 Future applicability. (a) General. This section sets forth the applicability of the Act to museums and Federal agencies after expiration of the statutory deadlines...

  10. 43 CFR 10.13 - Future applicability.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.13 Future applicability. (a) General. This section sets forth the applicability of the Act to museums and Federal agencies after expiration of the statutory deadlines...

  11. 43 CFR 10.13 - Future applicability.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.13 Future applicability. (a) General. This section sets forth the applicability of the Act to museums and Federal agencies after expiration of the statutory deadlines...

  12. 43 CFR 10.13 - Future applicability.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REPATRIATION REGULATIONS Human Remains, Funerary Objects, Sacred Objects, or Objects of Cultural Patrimony in Museums and Federal Collections § 10.13 Future applicability. (a) General. This section sets forth the applicability of the Act to museums and Federal agencies after expiration of the statutory deadlines...

  13. 1 CFR 10.13 - Coverage of prior years.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Coverage of prior years. 10.13 Section 10.13 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER PRESIDENTIAL PAPERS Annual Publication § 10.13 Coverage of prior years. The...

  14. 1 CFR 10.13 - Coverage of prior years.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Coverage of prior years. 10.13 Section 10.13 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER PRESIDENTIAL PAPERS Annual Publication § 10.13 Coverage of prior years. The...

  15. 46 CFR 30.10-13 - Cofferdam-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Cofferdam-TB/ALL. 30.10-13 Section 30.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS GENERAL PROVISIONS Definitions § 30.10-13 Cofferdam—TB/ALL. The term cofferdam means a void or empty space separating two or more compartments for...

  16. 46 CFR 30.10-13 - Cofferdam-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Cofferdam-TB/ALL. 30.10-13 Section 30.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS GENERAL PROVISIONS Definitions § 30.10-13 Cofferdam—TB/ALL. The term cofferdam means a void or empty space separating two or more compartments for...

  17. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  18. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  19. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  20. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  1. 46 CFR 188.10-13 - Coast Guard District Commander.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Coast Guard District Commander. 188.10-13 Section 188.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-13 Coast Guard District...

  2. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 1 2011-10-01 2011-10-01 false List of Migratory Birds. 10.13 Section 10... GENERAL PROVISIONS Definitions § 10.13 List of Migratory Birds. (a) Legal authority for this list. The Migratory Bird Treaty Act (MBTA) in 16 U.S.C. 703-711, the Fish and Wildlife Improvement Act of 1978, 16...

  3. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 1 2012-10-01 2012-10-01 false List of Migratory Birds. 10.13 Section 10... GENERAL PROVISIONS Definitions § 10.13 List of Migratory Birds. (a) Legal authority for this list. The Migratory Bird Treaty Act (MBTA) in 16 U.S.C. 703-711, the Fish and Wildlife Improvement Act of 1978, 16...

  4. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 1 2013-10-01 2013-10-01 false List of Migratory Birds. 10.13 Section 10... GENERAL PROVISIONS Definitions § 10.13 List of Migratory Birds. (a) Legal authority for this list. The Migratory Bird Treaty Act (MBTA) in 16 U.S.C. 703-711, the Fish and Wildlife Improvement Act of 1978, 16...

  5. The amino acid sequence of protein CM-3 from Dendroaspis polylepis polylepis (black mamba) venom.

    PubMed

    Joubert, F J

    1985-01-01

    Protein CM-3 from Dendroaspis polylepis polylepis venom was purified by gel filtration and ion exchange chromatography. It comprises 65 amino acids including eight half-cystines. The complete amino acid sequence of protein CM-3 has been elucidated. The sequence (residues 1-50) resembles that of the N-terminal sequence of the subunits of a synergistic type protein and residues 51-65 that of the C-terminal sequence of an angusticeps type protein. Mixtures of protein CM-3 and angusticeps type proteins showed no apparent synergistic effect, in that their toxicity in combination was no greater than the sum of their individual toxicities.

  6. Smart-power integrated circuits to drive piezoelectric actuators for a cm3 microrobot system

    NASA Astrophysics Data System (ADS)

    Puig-Vidal, Manel; Lopez-Sanchez, J.; Miribel-Catala, P.; Montane, Enric; Bota, Sebastian A.; Samitier, Josep; Simu, Urban; Johansson, Stefan A. I.

    2001-08-01

    Today, the use of robots for self acting tasks in applications ranging from biology and medicine to microsystems technology demand miniaturized dimensions and high-precision handling techniques. A lot of these tasks have been carried out by humans, but the manual capabilities are restricted to certain tolerances. Transport and manipulation of biological cells or assembly of micromechanical parts are the best suited applications for microrobots with sizes about cm3. Low cost and high-resolution actuators are critical performances which determine to choose piezoceramic materials as more suitable for micropositioning and micromanipulation units of a cm3 microrobot. Smart Piezoactuator Unit (SPUs) as a basic element of a new generation of cm3 microrobots have been developped. The main characteristic of this proposed Smart Piezoactuator Unit system is the integration of driving circuitry with the piezoelectric actuators and to include a serial communication interface to minimize the number of power and command wires. Micropositioning and micromanipulation units are developed combining properly 6 Smart Piezoactuator Units each one. A BCD technology (Bipolar, CMOS, DMOS) is used to design high voltage smart power integrated circuit for these Smart Piezoactuator Units. Using this technology we integrate in the same chip 4 power drivers with its control and protection circuitry.

  7. Accuracy of free energies of hydration using CM1 and CM3 atomic charges.

    PubMed

    Udier-Blagović, Marina; Morales De Tirado, Patricia; Pearlman, Shoshannah A; Jorgensen, William L

    2004-08-01

    Absolute free energies of hydration (DeltaGhyd) have been computed for 25 diverse organic molecules using partial atomic charges derived from AM1 and PM3 wave functions via the CM1 and CM3 procedures of Cramer, Truhlar, and coworkers. Comparisons are made with results using charges fit to the electrostatic potential surface (EPS) from ab initio 6-31G* wave functions and from the OPLS-AA force field. OPLS Lennard-Jones parameters for the organic molecules were used together with the TIP4P water model in Monte Carlo simulations with free energy perturbation theory. Absolute free energies of hydration were computed for OPLS united-atom and all-atom methane by annihilating the solutes in water and in the gas phase, and absolute DeltaGhyd values for all other molecules were computed via transformation to one of these references. Optimal charge scaling factors were determined by minimizing the unsigned average error between experimental and calculated hydration free energies. The PM3-based charge models do not lead to lower average errors than obtained with the EPS charges for the subset of 13 molecules in the original study. However, improvement is obtained by scaling the CM1A partial charges by 1.14 and the CM3A charges by 1.15, which leads to average errors of 1.0 and 1.1 kcal/mol for the full set of 25 molecules. The scaled CM1A charges also yield the best results for the hydration of amides including the E/Z free-energy difference for N-methylacetamide in water.

  8. Kidney Injury Molecule-1: A Translational Journey

    PubMed Central

    Bonventre, Joseph V.

    2014-01-01

    Kidney injury molecule-1 (KIM-1, also named TIM-1 and HAVCR-1) was identified as the most highly upregulated protein in the proximal tubule of the kidney after injury. This protein is present with injury in multiple species including man, and also after a large number of acute and chronic insults to the kidney. It is a type-1 membrane protein whose ectodomain is released into the lumen of the tubule. The ectodomain is heavily glycosylated and stable and appears in the urine after injury. It has been qualified by the United States Food and Drug Administration and the European Medicines Agency for preclinical assessment of nephrotoxicity and on a case-by-case basis for clinical evaluation. As a biomarker in humans, its utility has been demonstrated in acute and chronic injury and in renal cell carcinoma, a condition similar to injury, where there is dedifferentiation of the epithelial cell. KIM-1 is a phosphatidylserine receptor which recognizes apoptotic cells directing them to lysosomes. It also serves as a receptor for oxidized lipoproteins and hence is important for uptake of components of the tubular lumen which may be immunomodulatory and/or toxic to the cell. KIM-1 is unique in being the first molecule, not also present on myeloid cells, that transforms kidney proximal epithelial cells into semi-professional phagocytes. Data suggest that KIM-1 expression is protective during early injury, whereas in chronic disease states, prolonged KIM-1 expression may be maladaptive and may represent a target for therapy of chronic kidney disease. PMID:25125746

  9. Improvement of surface albedo parameterization within a regional climate model (RegCM3)

    NASA Astrophysics Data System (ADS)

    Bao, Y.; Lü, S.

    2009-03-01

    A parameterization for calculating surface albedo of Solar Zenith Angel (SZA) dependence with coefficient for each vegetation type determined on the Moderate Resolution Imaging Spectro-radiometer (MODIS) reformed by the Bidirectional Reflectance Distribution Function (BRDF) is incorporated within the latest Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model (RegCM3), and evaluated with a high resolution one-way nesting simulation in China using the Climate Research Unit (CRU) data and the observations from the Field Experiment on Interaction between Land and Atmosphere in Arid Region of Northwest China (NWC-ALIEX). The performance of the SZA method modeling surface characteristic is investigated.Results indicate, RegCM with SZA method (RCM_SZA) considerably improve the cold bias of original RegCM (RCM_ORI) in air surface temperature in East Asia with 1.2 degree increased in summer due to the lower albedo produced by SZA method which makes more solar radiation absorbed by the surface and used for heating the atmosphere near to the surface. The simulated diurnal cycle of ground temperature conforms fairly well to the observation in the nesting simulation in Northwest China, especially during the noon time when the SZA has the lowest value. However, the modification can not obviously affect the East Asia summer monsoon precipitation simulation although RCM_SZA produce more evapo-transpiration in surface with more than 2 Wm-2 increases in simulated latent heat fluxes both in East Asia and in Northwest China compared to RCM_ORI.

  10. 46 CFR 39.10-13 - Submission of vapor control system designs-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Submission of vapor control system designs-TB/ALL. 39.10-13 Section 39.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS VAPOR CONTROL SYSTEMS General § 39.10-13 Submission of vapor control system designs—TB/ALL. (a) Plans, calculations,...

  11. 46 CFR 39.10-13 - Submission of vapor control system designs-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Submission of vapor control system designs-TB/ALL. 39.10-13 Section 39.10-13 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS VAPOR CONTROL SYSTEMS General § 39.10-13 Submission of vapor control system designs—TB/ALL. (a) Plans, calculations,...

  12. Evaluation and analysis of RegCM3 simulated summer rainfall over the Huaihe River Basin of China

    NASA Astrophysics Data System (ADS)

    Zong, Peishu; Wang, Huijun

    2011-06-01

    This study evaluates the ability of the Abdus Salam International Center for Theoretical Physics (ICTP) version 3 Regional Climate Model (RegCM3) in simulating the summer rainfall amount and distribution and large-scale circulation over the Huaihe River basin of China. We conducted the simulation for the period of 1982-2001 and the wet year of 2003 to test the ensemble simulation capacity of RegCM3. First, by comparing the simulated rainfall amount and distribution against the observations, it is found that RegCM3 can reproduce the rainfall pattern and its annual variations. In addition, the simulated spatial patterns of 850-hPa wind and specific humidity fields are close to the observations, although the wind speed and humidity values are larger. Finally, the ensemble simulation of RegCM3 for summer 2003 failed to capture the spatial distribution and underestimated the magnitude of the precipitation anomalies, and the reasons are analyzed.

  13. High resolution climate change simulation of the 21st century over East Asia by RegCM3

    NASA Astrophysics Data System (ADS)

    Gao, Xuejie

    2010-05-01

    To meet the increasing demands from the climate change impact assessment studies, a high resolution climate change simulation over East Asia region has being performed in the National Climate Center of the China Meteorological Administration. The model employed in the study is the Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model (RegCM3). A global model of the CCSR/NIES/FRCGC MIROC3.2_hires is selected to drive RegCM3 because of its high resolution (T106) and its good performances in simulating the present day climate over the region. The simulation is conducted at 25-km grid spacing for the period of 1951-2100. Observed CO2 concentration are used for the present day simulation of 1951-2000 and the emission scenario of IPCC SRES A1B is used as the GHG (greenhouse gases) forcing. Simulations of present day climate over China by RegCM3 and MIROC3.2_hires are compared against observation to valid the model performances. Results show that both models reproduced the general pattern of surface air temperature and precipitation well over the region. Compared to the driving MIROC3.2_hires, RegCM3 provides with more spatial details of the surface fields. Differed from previous GCM-RegCM3 simulations, the RegCM3 did not improves the general pattern of the precipitation due to the good performances of MIROC3.2_hires. Preliminary analysis of the future changes simulated by the two models' show difference, in particular during June-July-August. For example while the MIROC3.2_hires projected a prevailing increase of precipitation in JJA over China, the RegCM3 projected extended areas of decreased precipitation. The data are available for those interested from the community of climate change impacts studies.

  14. Hn PAHs and the 2940 and 28050/cm (3.40 and 3.51 Microns) Infrared Emission Features

    NASA Technical Reports Server (NTRS)

    Bernstein, Max; Sandford, Scott; Allamandola, Louis; Witteborn, Fred (Technical Monitor)

    1996-01-01

    The 3150-2700/cm (3.17-3.70 microns) range of the spectra of a number of Ar matrix isolated PAHs containing excess H atoms (Hn-PAHs) are presented. This region covers features produced by aromatic and aliphatic C-H stretching vibrations as well as overtone and combination bands involving lower lying fundamentals. It is demonstrated that the aliphatic C-H stretches in molecules of this type having low-to-modest excess H coverage provide excellent fits to a number of the weak emission features superposed on the plateau between 3080 and 2700/cm (3.25 and 3.7 microns) in the spectra of many planetary nebulae, reflection nebulae, and HII regions. Higher H coverage is implied for a few objects. We compare these results in context with the other suggested identifications of the emission features in the 2950-2700/cm (3.39-3.70 microns) region and briefly discuss their astrophysical implications.

  15. Sensitivity of the GCM driven summer monsoon simulations to cumulus parameterization schemes in nested RegCM3

    NASA Astrophysics Data System (ADS)

    Sinha, P.; Mohanty, U. C.; Kar, S. C.; Dash, S. K.; Kumari, S.

    2013-04-01

    The regional climate model (RegCM3) from the Abdus Salam International Centre for Theoretical Physics has been used to simulate the Indian summer monsoon for three different monsoon seasons such as deficit (1987), excess (1988) and normal (1989). Sensitivity to various cumulus parameterization and closure schemes of RegCM3 driven by the National Centre for Medium Range Weather Forecasting global spectral model products has been tested. The model integration of the nested RegCM3 is conducted using 90 and 30-km horizontal resolutions for outer and inner domains, respectively. The India Meteorological Department gridded rainfall (1° × 1°) and National Centre for Environment Prediction (NCEP)-Department of Energy (DOE) reanalysis-2 of 2.5° × 2.5° horizontal resolution data has been used for verification. The RegCM3 forced by NCEP-DOE reanalysis-2 data simulates monsoon seasons of 1987 and 1988 reasonably well, but the monsoon season of 1989 is not represented well in the model simulations. The RegCM3 runs driven by the global model are able to bring out seasonal mean rainfall and circulations well with the use of the Grell and Anthes-Kuo cumulus scheme at 90-km resolution. While the rainfall intensity and distribution is brought out well with the Anthes-Kuo scheme, upper air circulation features are brought out better by the Grell scheme. The simulated rainfall distribution is better with RegCM3 using the MIT-Emanuel cumulus scheme for 30-km resolution. Several statistical analyses, such as correlation coefficient, root mean square error, equitable threat score, confirm that the performance of MIT-Emanuel scheme at 30-km resolution is better in simulating all-India summer monsoon rainfall. The RegCM3 simulated rainfall amount is more and closer to observations than that from the global model. The RegCM3 has corrected its driven GCM in terms of rainfall distribution and magnitude over some parts of India during extreme years. This study brings out several

  16. New α-adrenergic property for synthetic MTβ and CM-3 three-finger fold toxins from black mamba.

    PubMed

    Blanchet, Guillaume; Upert, Gregory; Mourier, Gilles; Gilquin, Bernard; Gilles, Nicolas; Servent, Denis

    2013-12-01

    Despite their isolation more than fifteen years ago from the venom of the African mamba Dendroaspis polylepis, very few data are known on the functional activity of MTβ and CM-3 toxins. MTβ was initially classified as a muscarinic toxin interacting non-selectively and with low affinity with the five muscarinic receptor subtypes while no biological function was determined for CM-3. Recent results highlight the multifunctional activity of three-finger fold toxins for muscarinic and adrenergic receptors and reveal some discrepancies in the pharmacological profiles of their venom-purified and synthetic forms. Here, we report the pharmacological characterization of chemically-synthesized MTβ and CM-3 toxins on nine subtypes of muscarinic and adrenergic receptors and demonstrate their high potency for α-adrenoceptors and in particular a sub-nanomolar affinity for the α1A-subtype. Strikingly, no or very weak affinity were found for muscarinic receptors, highlighting that pharmacological characterizations of venom-purified peptides may be risky due to possible contaminations. The biological profile of these two homologous toxins looks like that one previously reported for the Dendroaspis angusticeps ρ-Da1a toxin. Nevertheless, MTβ and CM-3 interact more potently than ρ-Da1a with α1B- and α1D-AR subtypes. A computational analysis of the stability of the MTβ structure suggests that mutation S38I, could be involved in this gain in function.

  17. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... esters. 721.9965 Section 721.9965 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical... acids, C10-13 - branched, vinyl esters (PMN P-97-482; CAS No. 184785-38-4) is subject to reporting...

  18. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... esters. 721.9965 Section 721.9965 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical... acids, C10-13 - branched, vinyl esters (PMN P-97-482; CAS No. 184785-38-4) is subject to reporting...

  19. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... esters. 721.9965 Section 721.9965 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical... acids, C10-13 - branched, vinyl esters (PMN P-97-482; CAS No. 184785-38-4) is subject to reporting...

  20. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... esters. 721.9965 Section 721.9965 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical... acids, C10-13 - branched, vinyl esters (PMN P-97-482; CAS No. 184785-38-4) is subject to reporting...

  1. 40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... esters. 721.9965 Section 721.9965 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.9965 Fatty acids, C10-13 - branched, vinyl esters. (a) Chemical... acids, C10-13 - branched, vinyl esters (PMN P-97-482; CAS No. 184785-38-4) is subject to reporting...

  2. Outcomes in men with large prostates (≥ 60 cm(3)) treated with definitive proton therapy for prostate cancer.

    PubMed

    McGee, Lisa; Mendenhall, Nancy P; Henderson, Randal H; Morris, Christopher G; Nichols, Romaine C; Marcus, Robert J; Li, Zuofeng; Mendenhall, William M; Williams, Christopher R; Hoppe, Bradford S

    2013-04-01

    Large prostate size is associated with higher rates of genitourinary and gastrointestinal toxicities after definitive treatment for prostate cancer, and because of this many men will undergo cytoreduction with androgen deprivation therapy (ADT) before definitive therapy, which results in its own unique toxicities and worsens quality of life. This series investigates genitourinary and gastrointestinal toxicity in men with large prostates (> 60 cm(3)) undergoing definitive proton therapy (PT) for prostate cancer. Material and methods. From 2006 to 2010, 186 men with prostates ≥ 60 cm(3) were treated with definitive PT (median dose, 78 CGE) for low- (47%), intermediate- (37%) and high-risk (16%) prostate cancer. Median prostate size was 76 cm(3) (range, 60-143 cm(3)) and pretreatment IPSS was > 15 in 27%. At baseline, 51% were managed for obstructive symptoms with transurethral resection of the prostate (TURP) (9.7%) or medical management with α blockers (32%), 5 α-reductase inhibitors (15%), and/or saw palmetto (11%). Fourteen men received ADT for cytoreduction. Results. Median follow-up was two years. Grade 3 genitourinary toxicities occurred in 14 men, including temporary catheterization (n = 7), TURP (n = 6), and balloon dilation for urethral stricture (n = 1). Multivariate analysis demonstrated pretreatment medical management (p = 0.0065) and pretreatment TURP (p = 0.0002) were significantly associated with grade 3 genitourinary toxicity. One man experienced grade 3 gastrointestinal toxicity and 15 men had grade 2 gastrointestinal toxicities. On multivariate analysis, dose > 78 CGE was associated with increased grade 2 + gastrointestinal toxicity (p = 0.0142). Conclusion. Definitive management of men with large prostates without ADT was associated with low rates of genitourinary and gastrointestinal toxicity.

  3. Tellurite-, tellurate-, and selenite-based anaerobic respiration by strain CM-3 isolated from gold mine tailings.

    PubMed

    Maltman, Chris; Piercey-Normore, Michele D; Yurkov, Vladimir

    2015-09-01

    The newly discovered strain CM-3, a Gram-negative, rod-shaped bacterium from gold mine tailings of the Central Mine in Nopiming Provincial Park, Canada, is capable of dissimilatory anaerobic reduction of tellurite, tellurate, and selenite. CM-3 possesses very high level resistance to these oxides, both aerobically and anaerobically. During aerobic growth, tellurite and tellurate resistance was up to 1500 and 1000 µg/ml, respectively. In the presence of selenite, growth occurred at the highest concentration tested, 7000 µg/ml. Under anaerobic conditions, resistance was decreased to 800 µg/ml for the Te oxides; however, much like under aerobic conditions, growth with selenite still took place at 7000 µg/ml. In the absence of oxygen, CM-3 couples oxide reduction to an increase in biomass. Following an initial drop in viable cells, due to switching from aerobic to anaerobic conditions, there was an increase in CFU/ml greater than one order of magnitude in the presence of tellurite (6.6 × 10(3)-8.6 × 10(4) CFU/ml), tellurate (4.6 × 10(3)-1.4 × 10(5) CFU/ml), and selenite (2.7 × 10(5)-5.6 × 10(6) CFU/ml). A control culture without metalloid oxides showed a steady decrease in CFU/ml with no recovery. ATP production was also increased in the presence of each oxide, further indicating anaerobic respiration. Partial 16S rRNA gene sequencing revealed a 99.0 % similarity of CM-3 to Pseudomonas reactans.

  4. Sensitivity of simulated extreme precipitation and temperature to convective parameterization using RegCM3 in China

    NASA Astrophysics Data System (ADS)

    Hui, Pinhong; Tang, Jianping; Wang, Shuyu; Wu, Jian

    2015-10-01

    In this study, the regional climate model of RegCM3 is applied to investigate the sensitivity of regional climate over China using four cumulus parameterizations, the modified Anthes-Kuo (AK), the Grell with Arakawa-Schubert closure, the Grell with Fritsch-Chappell closure, and the MIT-Emanuel (EM). The model was integrated over the period of 1982 to 2001 using the NCEP Reanalysis data NNRP2 as boundary conditions. RegCM3 coupled with various cumulus parameterizations is evaluated firstly as for its ability to represent regional climatology and climate extreme indices, and the results show that simulated regional climate in China is sensitive to the option of cumulus parameterizations. All the cumulus schemes produce a northward expansion of heavy rain area and an underestimation of surface air temperature. For precipitation, the AK scheme simulates relatively better magnitude, while the EM scheme has more reliable performance on the spatial distribution. RegCM3 can represent the spatial distributions of extreme indices for both precipitation and temperature, as well as their decadal trends irrelevant to the cumulus parameterizations. However, the model underestimates the consecutive dry days and overestimates the three extreme wet indices, with the EM scheme giving the worst result. Slight underestimations of extreme temperature indices are detected in all cumulus parameterization scheme runs. The shapes of probability distribution functions for extreme indices are correctly produced, though the probabilities of extreme dry and warm events are underestimated.

  5. 40 CFR 721.10178 - Distillates (Fischer-Tropsch), hydroisomerized middle, C10-13-branched alkane fraction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...), hydroisomerized middle, C10-13-branched alkane fraction. 721.10178 Section 721.10178 Protection of Environment...), hydroisomerized middle, C10-13-branched alkane fraction. (a) Chemical substance and significant new uses subject... middle, C10-13-branched alkane fraction (PMN P-04-319; CAS No. 642928-30-1) is subject to reporting...

  6. European Meeting of Associated School Representatives. Mauerbach/Vienna (Austria): 10-13 May 1982.

    ERIC Educational Resources Information Center

    International Understanding at School, 1982

    1982-01-01

    A meeting held in Mauerbach, Austria, from May 10-13, 1982, to consider the role of the Associated Schools in implementing the recommendations concerning education for international understanding and peace adopted by the general conference held in Chad earlier that year is described. (RM)

  7. Regional Climate Responses To Planetary-Scale Geoengineering Activities, as Modeled Using climateprediction.net/HadCM3L

    NASA Astrophysics Data System (ADS)

    Ricke, K.

    2009-12-01

    Concerns that climate mitigation is occurring too slowly, or that there may be a rapid "climate surprise," have lead to renewed dialogue within the scientific community about cooling the planet through geoengineering, specifically stratospheric albedo modification (SAM). There is little consensus about regional hydrological effects of such activities despite a recent spate of climate modeling studies looking at its potential impacts. Here we present the results from one large-ensemble experiment that used Hadley Centre Coupled Model, version 3 with reduced resolution over the ocean (HadCM3L), implemented through climateprediction.net. The analysis examines 54 globally-uniform stratospheric optical depth modification scenarios designed to stabilize global temperatures under SRES A1B. We present normalized regional temperature anomalies versus normalized regional precipitation and subsurface runoff anomalies (for example, see Figure 1) and the results of regression analyses to quantify the relationships between level of stratospheric optical property modification (i.e., geoengineering) and regional hydrology. Results show that while such shortwave compensations for longwave anthropogenic forcings does generally return regional climates to closer to their baseline climate states than the no-geoengineering, business-as-usual scenarios, the magnitudes and sensitivities of regional responses to this type of activity, as modeled in HadCM3L, are highly variable. Regions, such as Eastern China and India, migrate away from their baseline climate states in different ways, illustrating the impossibility of simultaneous stabilization of regional climates. The linearity of the effect of incrementally increasing stratospheric optical depth also varies regionally. Figure 1: Normalized regional temperature and precipitation anomalies (<2020s>-<1990s> and <2070s>-<1990s>) in units of baseline standard deviations for each region). Each grayscale point in-series near the origin

  8. High-resolution δ13C measurements on ancient air extracted from less than 10 cm3 of ice

    NASA Astrophysics Data System (ADS)

    Leuenberger, M. C.; Eyer, M.; Nyfeler, P.; Stauffer, B.; Stocker, T. F.

    2003-04-01

    A new method for δ13C analysis of very small air amounts of less than 0.5 cm3 STP was developed. This corresponds to less than 10 g of ice. It is based on the needle-crasher technique, which is routinely used for CO2 concentration measurements by infrared laser absorption. The extracted air is slowly expanded into a large volume through a water trap held at -70 °C where the pressure is measured. This sampled air is then carried by a high helium flux through a preconcentration system to separate CO2 cryogenically from the air. The small CO2 amount is then released into a low helium stream which forces the CO2 via an open split device to a mass spectrometer. The overall precision, based on replicates of standard air without crushing, is significantly better than 0.1‰ for a single analysis, and is further improved by a triplicate measurement of the same sample through a specially designed gas splitter. Performing δ13C measurements on ice air through the whole system, we reach a reproducibility of 0.12‰. Additional information is obtained through amplitude vs. pressure ratio determination, which results in a good control of the CO2 concentration (1 ppm precision for 1σ). The new method allows us to produce highly resolved records of atmospheric δ13C from air enclosed in ice, which is required to better understand the evolution and the temporal variability of the global carbon cycle.

  9. Particle- and gas-phase emissions of polycyclic aromatic hydrocarbons from two-stroke, 50-cm 3 mopeds

    NASA Astrophysics Data System (ADS)

    Spezzano, Pasquale; Picini, Paolo; Cataldi, Dario; Messale, Fabrizio; Manni, Claudio

    2008-06-01

    The emissions of gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs) were evaluated in the exhaust of 10 mopeds (4 EURO-0, 4 EURO-1 and 2 EURO-2) equipped with two-stroke engines with displacement of 50 cm3. Sampling was performed on a dynamometer bench both during the "cold-start" and the "hot" phases of the ECE-47 driving cycle. Eighteen PAHs were quantified and total PAH emission factors (∑PAH) ranged from 1790 to 15,059 μg km-1. Expressed in benzo(a)pyrene equivalent (BaPeq), emission factors ranged 4.7-86.3 μg km-1. PAH emissions are reduced according to the legislation class: EURO-0>EURO-1>EURO-2. PAH emission factors were greater during the cold-start phase than the hot phase of the ECE-47 cycle. Results show that despite their small engine size, two-stroke mopeds can emit amounts of particulate PAHs comparable or even higher than PAH emissions reported elsewhere from gasoline- and diesel-powered passenger cars and light- and heavy-duty vehicles.

  10. The eastern Tropical Pacific hydroclimate over the last 120kyr: a perspective from HadCM3.

    NASA Astrophysics Data System (ADS)

    Roberts, W. H. G.; Valdes, P. J.

    2014-12-01

    The focus of the majority of studies looking into the evolving tropical pacific climate on glacial/interglacial timescales has been the role of the changing orbital forcing. While this is of course the fundamental forcing that drives changes in the climate on these time scales, without a fully interactive Earth System Model the effects that the evolving ice sheets/sea level and green house gases have on the climate will be missed. In the absence of such models these other forcings must be imposed. While the impact on the temperature in both the high latitudes, and to some extent in the tropics, of all of the forcings is reasonably clear, their impact on the hydroclimate is less obvious. In this study we shall investigate what role all of the different forcings that vary over a glacial/interglacial cycle play on the hydroclimate in the eastern Tropical Pacific. We use as the basis of our study a set of three climate model experiments using the model HadCM3. Each of these simulates the last 120 thousand years as a series of time slices in one of three configurations: varying the orbital forcing; varying the orbital and greenhouse gas forcing; varying the orbital, greenhouse and ice sheet/sea level forcing. With these experiments we can deconvolve the role that each forcing plays. We will show that, in addition to the orbital forcing, both the greenhouse gas forcing and the ice sheet configuration have a large impact on the eastern Tropical Pacific's hydroclimate. Using a set of more idealised model simulations we shall elucidate the mechanisms by which each of these different forcing mechanism causes the simulated changes.

  11. Coupling of a regional atmospheric model (RegCM3) and a regional oceanic model (FVCOM) over the maritime continent

    NASA Astrophysics Data System (ADS)

    Wei, Jun; Malanotte-Rizzoli, Paola; Eltahir, Elfatih A. B.; Xue, Pengfei; Xu, Danya

    2014-09-01

    Climatological high resolution coupled climate model simulations for the maritime continent have been carried out using the regional climate model (RegCM) version 3 and the finite volume coastal ocean model (FVCOM) specifically designed to resolve regions characterized by complex geometry and bathymetry. The RegCM3 boundary forcing is provided by the EMCWF-ERA40 re-analysis. FVCOM is embedded in the Global MITgcm which provides boundary forcing. The domain of the coupled regional model covers the entire South China Sea with its through-flow, the entire Indonesian archipelago with the Indonesian through-flow (ITF) and includes a large region in the western Pacific and eastern Indian oceans. The coupled model is able to provide stable and realistic climatological simulations for a specific decade of atmospheric-oceanic variables without flux correction. The major focus of this work is on oceanic properties. First, the coupled simulation is assessed against ocean-only simulations carried out under two different sets of air-sea heat fluxes. The first set, provided by the MITgcm, is proved to be grossly deficient as the heat fluxes are evaluated by a two-dimensional, zonally averaged atmosphere and the simulated SST have anomalous cold biases. Hence the MITgcm fluxes are discarded. The second set, the NCEP re-analysis heat fluxes, produces a climatological evolution of the SST with an average cold bias of ~-0.8 °C. The coupling eliminates the cold bias and the coupled SST evolution is in excellent agreement with the analogous evolution in the SODA re-analysis data. The detailed comparison of oceanic circulation properties with the International Nusantara Stratification and Transport observations shows that the coupled simulation produces the best estimate of the total ITF transport through the Makassar strait while the transports of three ocean-only simulations are all underestimated. The annual cycle of the transport is also very well reproduced. The coupling also

  12. Intercellular Adhesion Molecule 1 Knockout Abrogates Radiation Induced Pulmonary Inflammation

    NASA Astrophysics Data System (ADS)

    Hallahan, Dennis E.; Virudachalam, Subbulakshmi

    1997-06-01

    Increased expression of intercellular adhesion molecule 1 (ICAM-1; CD54) is induced by exposure to ionizing radiation. The lung was used as a model to study the role of ICAM-1 in the pathogenesis of the radiation-induced inflammation-like response. ICAM-1 expression increased in the pulmonary microvascular endothelium and not in the endothelium of larger pulmonary vessels following treatment of mice with thoracic irradiation. To quantify radiation-induced ICAM-1 expression, we utilized fluorescence-activated cell sorting analysis of anti-ICAM-1 antibody labeling of pulmonary microvascular endothelial cells from human cadaver donors (HMVEC-L cells). Fluorochrome conjugates and UV microscopy were used to quantify the fluorescence intensity of ICAM in the irradiated lung. These studies showed a dose- and time-dependent increase in ICAM-1 expression in the pulmonary microvascular endothelium. Peak expression occurred at 24 h, while threshold dose was as low as 2 Gy. To determine whether ICAM-1 is required for inflammatory cell infiltration into the irradiated lung, the anti-ICAM-1 blocking antibody was administered by tail vein injection to mice following thoracic irradiation. Inflammatory cells were quantified by immunofluorescence for leukocyte common antigen (CD45). Mice treated with the anti-ICAM-1 blocking antibody showed attenuation of inflammatory cell infiltration into the lung in response to ionizing radiation exposure. To verify the requirement of ICAM-1 in the inflammation-like radiation response, we utilized the ICAM-1 knockout mouse. ICAM-1 was not expressed in the lungs of ICAM-1-deficient mice following treatment with thoracic irradiation. ICAM-1 knockout mice had no increase in the inflammatory cell infiltration into the lung in response to thoracic irradiation. These studies demonstrate a radiation dose-dependent increase in ICAM-1 expression in the pulmonary microvascular endothelium, and show that ICAM-1 is required for inflammatory cell infiltration

  13. Analysis of the present and future winter Pacific-North American teleconnection in the ECHAM5 global and RegCM3 regional climate models

    USGS Publications Warehouse

    Allan, Andrea M.; Hostetler, Steven W.; Alder, Jay R.

    2014-01-01

    We use the NCEP/NCAR Reanalysis (NCEP) and the MPI/ECHAM5 general circulation model to drive the RegCM3 regional climate model to assess the ability of the models to reproduce the spatiotemporal aspects of the Pacific-North American teleconnection (PNA) pattern. Composite anomalies of the NCEP-driven RegCM3 simulations for 1982–2000 indicate that the regional model is capable of accurately simulating the key features (500-hPa heights, surface temperature, and precipitation) of the positive and negative phases of the PNA with little loss of information in the downscaling process. The basic structure of the PNA is captured in both the ECHAM5 global and ECHAM5-driven RegCM3 simulations. The 1950–2000 ECHAM5 simulation displays similar temporal and spatial variability in the PNA index as that of NCEP; however, the magnitudes of the positive and negative phases are weaker than those of NCEP. The RegCM3 simulations clearly differentiate the climatology and associated anomalies of snow water equivalent and soil moisture of the positive and negative PNA phases. In the RegCM3 simulations of the future (2050–2100), changes in the location and extent of the Aleutian low and the continental high over North America alter the dominant flow patterns associated with positive and negative PNA modes. The future projections display a shift in the patterns of the relationship between the PNA and surface climate variables, which suggest the potential for changes in the PNA-related surface hydrology of North America.

  14. Impact of resolution on regional climate modeling in the source region of Yellow River with complex terrain using RegCM3

    NASA Astrophysics Data System (ADS)

    Hui, Pinhong; Tang, Jianping; Wang, Shuyu; Wu, Jian; Niu, Xiaorui; Kang, Yue

    2016-07-01

    This paper presents results from a 20-year (1990-2009) simulation by RegCM3 with both 45- and 15-km horizontal resolutions. The research focuses on the source region of Yellow River and its surrounding area, which is located on the northeast edge of the Tibetan Plateau with its very complex topography. Driven by the ECMWF ERA-interim reanalysis data, RegCM3 displays reasonable ability to reproduce the spatial patterns, annual cycles, and the interannual variabilities of regional surface climate, though the model shows wet and cold bias. The model's performance is more close to observation for the source region of Yellow River than the other part of the analysis region, and the application of high resolution of 15 km demonstrates better skill with less bias for mean climate and larger correlation coefficients for interannual variability at most stations. However, the high-resolution simulation shows little advantage for reproducing the variations of precipitation and surface air temperature with altitude. The RegCM3 model also generally reproduces the probability distribution functions (PDFs) of surface climate and, consequently, the occurrence of climatic extremes and extreme indices. The simulation with high resolution again proves to be more reliable to generate climatic extremes over complex terrain of the source region of the Yellow River, related to its better representation of complex terrain and local processes.

  15. The dynamical core, physical parameterizations, and basic simulation characteristics of the atmospheric component AM3 of the GFDL global coupled model CM3

    USGS Publications Warehouse

    Donner, L.J.; Wyman, B.L.; Hemler, R.S.; Horowitz, L.W.; Ming, Y.; Zhao, M.; Golaz, J.-C.; Ginoux, P.; Lin, S.-J.; Schwarzkopf, M.D.; Austin, J.; Alaka, G.; Cooke, W.F.; Delworth, T.L.; Freidenreich, S.M.; Gordon, C.T.; Griffies, S.M.; Held, I.M.; Hurlin, W.J.; Klein, S.A.; Knutson, T.R.; Langenhorst, A.R.; Lee, H.-C.; Lin, Y.; Magi, B.I.; Malyshev, S.L.; Milly, P.C.D.; Naik, V.; Nath, M.J.; Pincus, R.; Ploshay, J.J.; Ramaswamy, V.; Seman, C.J.; Shevliakova, E.; Sirutis, J.J.; Stern, W.F.; Stouffer, R.J.; Wilson, R.J.; Winton, M.; Wittenberg, A.T.; Zeng, F.

    2011-01-01

    The Geophysical Fluid Dynamics Laboratory (GFDL) has developed a coupled general circulation model (CM3) for the atmosphere, oceans, land, and sea ice. The goal of CM3 is to address emerging issues in climate change, including aerosol-cloud interactions, chemistry-climate interactions, and coupling between the troposphere and stratosphere. The model is also designed to serve as the physical system component of earth system models and models for decadal prediction in the near-term future-for example, through improved simulations in tropical land precipitation relative to earlier-generation GFDL models. This paper describes the dynamical core, physical parameterizations, and basic simulation characteristics of the atmospheric component (AM3) of this model. Relative to GFDL AM2, AM3 includes new treatments of deep and shallow cumulus convection, cloud droplet activation by aerosols, subgrid variability of stratiform vertical velocities for droplet activation, and atmospheric chemistry driven by emissions with advective, convective, and turbulent transport. AM3 employs a cubed-sphere implementation of a finite-volume dynamical core and is coupled to LM3, a new land model with ecosystem dynamics and hydrology. Its horizontal resolution is approximately 200 km, and its vertical resolution ranges approximately from 70 m near the earth's surface to 1 to 1.5 km near the tropopause and 3 to 4 km in much of the stratosphere. Most basic circulation features in AM3 are simulated as realistically, or more so, as in AM2. In particular, dry biases have been reduced over South America. In coupled mode, the simulation of Arctic sea ice concentration has improved. AM3 aerosol optical depths, scattering properties, and surface clear-sky downward shortwave radiation are more realistic than in AM2. The simulation of marine stratocumulus decks remains problematic, as in AM2. The most intense 0.2% of precipitation rates occur less frequently in AM3 than observed. The last two decades of

  16. Climate Impact on South America due to Land Use Degradation of Amazon Rainforest during Winter and Summer Periods by RegCM3 Model

    NASA Astrophysics Data System (ADS)

    Silva, M. E. S.; Da Rocha, R.; Pereira, G.

    2015-12-01

    In this study we investigated the climatic impact over South America region due to the increasing of deforestation at the eastern and southern regions of Amazon through the use of the climate model RegCM3 with 50 km of spatial resolution. Many studies, among global and regional models have been used to simulate climatic impact due to deforestation. Most of them used relatively coarse resolution, small domains over South America, besides do not consider deforestation as usually observed. In order to verify the RegCM3 ability to simulate climate impacts due to Amazon deforestation including relatively higher horizontal resolutions, 50 km, a larger domain, the whole South America, deforested areas more similar to the route-shaped commonly seen, and a landuse updating, the model was run for the 2001-2006 period. As the major part of the previous studies focusing Amazon deforestation, RegCM3-50km simulated over degraded areas air temperature increase, ranging from 1.0 to 2.5oC, and precipitation decreasing, ~10%. These aspects are mainly resulting from soil water depletion and roughness vegetation decreasing, both inhibiting evapotranspiration processes. Apart from these results, the model with 50 km simulated precipitation increasing, ~10%, over the eastern South America and adjacent South Atlantic ocean, after Amazon deforestation. Seeking for physical related reasons able to provide the precipitation increasing during rainy seasons, over eastern South America, we found out that upper levels high pressure system (the Bolivian High) intensification, coupled to the southeastward trough, what follows the low troposphere warming, seems to contribute to the precipitation increasing. The climatic impact simulated for winter seasons presents strongest values for areas with altered landuse, over the north region of South America.

  17. Tuning The Sea-Ice Seasonal Cycle Of HadCM3: Can It Reproduce Observed Trends In Sea-Ice?

    NASA Astrophysics Data System (ADS)

    Tett, S. F.; Roach, L.; Rae, C.; Cartis, C.; Mineter, M.; Steig, E. J.; Yamazaki, K.; Schurer, A. P.

    2015-12-01

    Since high quality satellite observations of sea-ice begin in 1979 Artic sea-ice extent has declined . Observed losses in Arctic sea-ice during September are greater than the majority of models in the CMIP5 archive and the multi-model average. In contrast Antarctic sea-ice has increased in contrast to an expected decline. We have carried out a set of perturbations to the HadCM3 model in which we changed the maximum ice area (a proxy for ice leads), albedo parameterizations, ice thermal conductivity and ocean diffusion. Changes in these parameters affected ice extent in both the Arctic and Antarctic. We used these simulations to identify four parameters that had most impact on minimum and maximum sea-ice extent in both hemispheres. To tune the model we used a Gauss-Newton algorithm to adjust those four parameters to minimize differences between simulated and observed sea-ice extents. With this new parameter set we then simulated the period 1940 to 2015 and compared with the default configuration of HadCM3. Compared to the default configuration the perturbed model had greater summer sea-loss in the Arctic and is consistent with observed loss estimates. However, in the Antarctic neither the perturbed or default simulations show an increase in sea-ice extent. This is in contrast to the observations which do show an increase in sea-ice extent.

  18. Coffee Beverage Quality Assessment Based on ETA/CPTEC-HadCM3 Model (A1B-IPCC/SRES Scenario), Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Giarolla, A.; Resende, N.; Chou, S. C.; Tavares, P. S.; Rodrigues, D. C.

    2012-04-01

    Environmental factors influence the coffee beverage quality and air temperature has a significant importance in this process. The grain maturation occurs very quickly in regions that present high temperatures and sometimes there is not enough time to complete all this phase adequately. In the other hand, with mild temperatures, the grain maturation occurs more slowly and it promotes a better quality beverage. The aim of this study was to assess the coffee beverage quality in the southeastern Brazil, based on climate projections using the Eta-CPTEC regional model driven by four members of an ensemble of the Met Office Hadley Centre Global Coupled climate model (HadCM3). The global model ensemble was run over the 21st century according to IPCC SRES, A1B emissions scenario. Each ensemble member presented different climate sensitivity in the analysis. The Eta-CPTEC-HadCM3 model was configured with a 40-km grid size and was run over the period of 1961-90 to represent a baseline climate, and over the period of 2011-2100 to simulate possible future changes and the effects on the coffee beverage quality. A coffee beverage quality classification, which depends on the annual air temperature proposed by Bressani (2007) and also, a quality coffee beverage sensory classification, based on Camargo and Cortez (1998) were considered in this study. An evaluation of the systematic errors (BIAS) for each member for the period from 1961 to 1990 was made. The results presented by Eta/CPTEC-HadCM3 model indicated that in the case of an occurrence of A1B emission scenario, the coffee beverage quality could be affected in this region due to the fact that the flavor may become stronger and unpleasant caused by rising air temperatures. The BIAS evaluation and subsequent errors removal demonstrated improvement in the scenarios simulations. A short review concerning agronomic techniques to mitigate extreme meteorological events or global warming on coffee crop based on Camargo (2010) also is

  19. Accurate quantum chemical modelling of the separation of Eu(3+) from Am(3+)/Cm(3+) by liquid-liquid extraction with Cyanex272.

    PubMed

    Cao, Xiaoyan; Zhang, Jun; Weissmann, Daniel; Dolg, Michael; Chen, Xuebo

    2015-08-28

    The experimentally observed extraction complexes of trivalent lanthanide Eu(3+) and actinide Am(3+)/Cm(3+) cations with Cyanex272 [bis(2,4,4-trimethylpentyl) phosphinic acid, denoted as HC272] and Cyanex301 [bis(2,4,4-trimethylpentyl) dithiophosphinic acid, denoted as HC301] have been studied by using relativistic energy-consistent 4f- and 5f-in-core pseudopotentials for trivalent f elements, combined with density functional theory and a continuum solvation model. It has been found that, as a result of hydrogen bonding, HC272 exists primarily as a self-associated species, whereas HC301 is preferably a monomer. The calculations show that in case of all three M(3+) (M = Eu, Am, Cm) ions for HC272 the extraction complexes M[H(C272)2]3 are formed prior to M(C272)3, whereas for HC301 the extraction complexes M(C301)3 have priority over M[H(C301)2]3. The calculated M-O and M-S bond lengths and the M-P distances of these preferred extraction complexes agree very well with the available experimental data. The obtained changes of the Gibbs free energies in the liquid-liquid extraction reactions (1): Maqu(3+) + 3(HC272)2,org→ M[H(C272)2]3,org + 3Haqu(+) and (2): Maqu(3+) + 3HC301org→ M(C301)3,org + 3Haqu(+) agree with the experimentally observed thermodynamical priorities of HC272 and HC301, i.e., HC272 prefers Eu(3+) over Am(3+)/Cm(3+) and HC301 prefers Am(3+)/Cm(3+) over Eu(3+). The obtained changes of the Gibbs free energies in reaction (2) (Eu, 68.1 kJ mol(-1); Am, 46.5 kJ mol(-1)) agree quite well with the experimental findings (Eu, 63.3 kJ mol(-1); Am, 44.1 kJ mol(-1)).

  20. Parameter Tuning and Calibration of RegCM3 with MIT-Emanuel Cumulus Parameterization Scheme over CORDEX East Asian Domain

    SciTech Connect

    Zou, Liwei; Qian, Yun; Zhou, Tianjun; Yang, Ben

    2014-10-01

    In this study, we calibrated the performance of regional climate model RegCM3 with Massachusetts Institute of Technology (MIT)-Emanuel cumulus parameterization scheme over CORDEX East Asia domain by tuning the selected seven parameters through multiple very fast simulated annealing (MVFSA) sampling method. The seven parameters were selected based on previous studies, which customized the RegCM3 with MIT-Emanuel scheme through three different ways by using the sensitivity experiments. The responses of model results to the seven parameters were investigated. Since the monthly total rainfall is constrained, the simulated spatial pattern of rainfall and the probability density function (PDF) distribution of daily rainfall rates are significantly improved in the optimal simulation. Sensitivity analysis suggest that the parameter “relative humidity criteria” (RH), which has not been considered in the default simulation, has the largest effect on the model results. The responses of total rainfall over different regions to RH were examined. Positive responses of total rainfall to RH are found over northern equatorial western Pacific, which are contributed by the positive responses of explicit rainfall. Followed by an increase of RH, the increases of the low-level convergence and the associated increases in cloud water favor the increase of the explicit rainfall. The identified optimal parameters constrained by the total rainfall have positive effects on the low-level circulation and the surface air temperature. Furthermore, the optimized parameters based on the extreme case are suitable for a normal case and the model’s new version with mixed convection scheme.

  1. Angiogenesis mediated by soluble forms of E-selectin and vascular cell adhesion molecule-1

    NASA Astrophysics Data System (ADS)

    Koch, Alisa E.; Halloran, Margaret M.; Haskell, Catherine J.; Shah, Manisha R.; Polverini, Peter J.

    1995-08-01

    ENDOTHELIAL adhesion molecules facilitate the entry of leukocytes into inflamed tissues. This in turn promotes neovascularization, a process central to the progression of rheumatoid arthritis, tumour growth and wound repair1. Here we test the hypothesis that soluble endothelial adhesion molecules promote angiogenesis2á¤-4. Human recombinant soluble E-selectin and soluble vascular cell adhesion molecule-1 induced chemotaxis of human endothelial cells in vitro and were angiogenic in rat cornea. Soluble E-selectin acted on endothelial cells in part through a sialyl Lewis-X-dependent mechanism, while soluble vascular cell adhesion molecule-1 acted on endothelial cells in part through a very late antigen (VLA)-4 dependent mechanism. The chemotactic activity of rheumatoid synovial fluid for endothelial cells, and also its angiogenic activity, were blocked by antibodies to either soluble E-selectin or soluble vascular cell adhesion molecule-1. These results suggest a novel function for soluble endothelial adhesion molecules as mediators of angiogenesis.

  2. Simulation of the GeoMIP G1 and G2 experiments with a perturbed parameter ensemble of HadCM3

    NASA Astrophysics Data System (ADS)

    Irvine, P. J.; Ridgwell, A. J.; Lunt, D. J.

    2012-12-01

    The geoengineering model intercomparison project is an attempt to assess the uncertainties in the effectiveness and climate impacts of solar radiation management (SRM) geoengineering using a multi-model ensemble (MME) of Global Circulation Models (GCM). Another approach for assessing GCM uncertainty is to use a perturbed parameter ensemble (PPE) generated from a single GCM. Although the PPE approach is limited in that all the members of the ensemble have many similarities it is still a useful way to explore uncertainty in GCM results. We simulate the G1 and G2 using a 27 member PPE of a fully-coupled CMIP3-era GCM, HadCM3, without using flux adjustments. The PPE we use is described in an article that has been submitted to the geoscientific model development journal. An analysis of the mean and spread of the PPE is made and comparisons are made with the geoMIP MME results. This comparison will support the geoMIP effort to identify the robust, and the uncertain, aspects of the simulated climate response to SRM geoengineering. This work will be complementary to the main GeoMIP MME approach and will test the utility of using PPEs of earlier generation GCMs alongside latest generation models.

  3. Perovskite CH3NH3PbI3(Cl) Single Crystals: Rapid Solution Growth, Unparalleled Crystalline Quality, and Low Trap Density toward 10(8) cm(-3).

    PubMed

    Lian, Zhipeng; Yan, Qingfeng; Gao, Taotao; Ding, Jie; Lv, Qianrui; Ning, Chuangang; Li, Qiang; Sun, Jia-Lin

    2016-08-03

    Single crystal reflects the intrinsic physical properties of a material, and single crystals with high-crystalline quality are highly desired for the acquisition of high-performance devices. We found that large single crystals of perovskite CH3NH3PbI3(Cl) could be grown rapidly from chlorine-containing solutions. Within 5 days, CH3NH3PbI3(Cl) single crystal as large as 20 mm × 18 mm × 6 mm was harvested. As a most important index to evaluate the crystalline quality, the full width at half-maximum (fwhm) in the high-resolution X-ray rocking curve (HR-XRC) of as-grown CH3NH3PbI3(Cl) single crystal was measured as 20 arcsec, which is far superior to so far reported CH3NH3PbI3 single crystals (∼1338 arcsec). The unparalleled crystalline quality delivered a low trap-state density of down to 7.6 × 10(8) cm(-3), high carrier mobility of 167 ± 35 cm(2) V(-1) s(-1), and long transient photovoltaic carrier lifetime of 449 ± 76 μs. The improvement in the crystalline quality, together with the rapid growth rate and excellent carrier transport property, provides state-of-the-art single crystalline hybrid perovskite materials for high-performance optoelectronic devices.

  4. Innovative approaches to exoplanet detection and characterization: Notes from the Nov 10-13 Keck Institute for Space Studies workshop

    NASA Astrophysics Data System (ADS)

    Young, Eliot; Traub, Wesley; Unwin, Stephen; Stapelfeldt, Karl

    2010-05-01

    A four-day workshop was convened on November 10-13, 2009 by the Keck Institute for Space Studies and JPL to consider innovative approaches to detecting and characterizing exoplanets and planetary systems. The program and many of the presentations can be found online: . We present some of the observational strategies discussed in this workshop and summarize some of the issues associated with them. In particular, we will highlight some of the advantages and shortcomings of suborbital and orbital (e.g., ESPA rings) observing platforms in the context of exoplanet detection and characterization.

  5. Transvaginal 3-d power Doppler ultrasound evaluation of the fetal brain at 10-13 weeks' gestation.

    PubMed

    Hata, Toshiyuki; Tanaka, Hirokazu; Noguchi, Junko

    2012-03-01

    The objective of this study was to measure the fetal brain volume (FBV) and vascularization and blood flow using transvaginal 3-D power Doppler (3DPD) ultrasound late in the first trimester of pregnancy. 3DPD ultrasound examinations with the VOCAL imaging analysis program were performed on 36 normal fetuses from 10-13 weeks' gestation. FBV and 3DPD indices related to the fetal brain vascularization (vascularization index [VI], flow index [FI] and vascularization flow index [VFI]) were calculated in each fetus. Intra- and interclass correlation coefficients and intra- and interobserver agreements of measurements were assessed. FBV was curvilinearly correlated well with the gestational age (R2 = 0.861, p < 0.0001). All 3-D power Doppler indices (VI, FI and VFI) showed no change at 10-13 weeks' gestation. FBV and all 3-D power Doppler indices (VI, FI and VFI) showed a correlation > 0.82, with good intra- and interobserver agreement. Our findings suggest that 3-D ultrasound is a superior means of evaluating the FBV in utero, and that 3-D power Doppler ultrasound histogram analysis may provide new information on the assessment of fetal brain perfusion.

  6. Investigating the Feedbacks between Land Surface Cover and North Atlantic Climate Variability in the HadCM3 Coupled Climate Model

    NASA Astrophysics Data System (ADS)

    Armstrong, E.; Valdes, P.; House, J.; Singarayer, J. S.

    2015-12-01

    The North Atlantic displays a number of major modes of decadal variability, namely the North Atlantic Oscillation (NAO) and the Atlantic Meridional Overturning Circulation (AMOC). On decadal to multi-decadal timescales, this unforced climate variability is expected to be more influential on the overall pattern of climate than anthropogenic forcing. Greater understanding of this decadal-scale variability is essential to improve its predictability, which in turn is vital to constrain uncertainty in decadal to centennial climate change predictions. Numerous studies have investigated how oceanic and atmospheric forcing modulates climate variability. However the feedbacks between the land surface and decadal variability have not been examined to the same degree. The land surface influences climate via biogeophysical and biogeochemical processes which interact and vary across a wide range of spatial and temporal scales. Increasing concentrations of CO2 are expected to drive a change in the distribution and physiology (i.e. stomatal conductance and leaf area index) of vegetation, which can alter land surface structure and influence biogeophysical processes. It is important to more accurately constrain if/how land surface cover influences decadal variability and the associated feedback mechanisms and how these may change in a warming climate. This sensitivity study will use the HadCM3 climate model to investigate the impact of a range of vegetation distributions on the strength and variability of the AMOC/NAO at increasing CO2 concentrations. We aim to elucidate feedbacks between the land surface, ocean and atmosphere in a coupled climate model and potential implications for decadal modelling studies.

  7. Sensitivity studies of high-resolution RegCM3 simulations of precipitation over the European Alps: the effect of lateral boundary conditions and domain size

    NASA Astrophysics Data System (ADS)

    Nadeem, Imran; Formayer, Herbert

    2016-11-01

    A suite of high-resolution (10 km) simulations were performed with the International Centre for Theoretical Physics (ICTP) Regional Climate Model (RegCM3) to study the effect of various lateral boundary conditions (LBCs), domain size, and intermediate domains on simulated precipitation over the Great Alpine Region. The boundary conditions used were ECMWF ERA-Interim Reanalysis with grid spacing 0.75∘, the ECMWF ERA-40 Reanalysis with grid spacing 1.125 and 2.5∘, and finally the 2.5∘ NCEP/DOE AMIP-II Reanalysis. The model was run in one-way nesting mode with direct nesting of the high-resolution RCM (horizontal grid spacing Δx = 10 km) with driving reanalysis, with one intermediate resolution nest (Δx = 30 km) between high-resolution RCM and reanalysis forcings, and also with two intermediate resolution nests (Δx = 90 km and Δx = 30 km) for simulations forced with LBC of resolution 2.5∘. Additionally, the impact of domain size was investigated. The results of multiple simulations were evaluated using different analysis techniques, e.g., Taylor diagram and a newly defined useful statistical parameter, called Skill-Score, for evaluation of daily precipitation simulated by the model. It has been found that domain size has the major impact on the results, while different resolution and versions of LBCs, e.g., 1.125∘ ERA40 and 0.7∘ ERA-Interim, do not produce significantly different results. It is also noticed that direct nesting with reasonable domain size, seems to be the most adequate method for reproducing precipitation over complex terrain, while introducing intermediate resolution nests seems to deteriorate the results.

  8. Present-day climatology and projected changes of warm and cold days in the CNRM-CM3 global climate model

    NASA Astrophysics Data System (ADS)

    Ballester, J.; Douville, H.; Chauvin, F.

    2009-01-01

    The impact of global warming on the warmest and coldest days of the annual cycle is explored according to an A2 scenario simulated by the CNRM-CM3 climate model in the framework of the IPCC AR4 intercomparison. Given the multi-model spread in IPCC projections, a validation strategy is proposed using the NCEP/NCAR reanalysis. Validation of the late twentieth century model climatology shows that warm and cold model events are slightly too long and infrequent. Although interannual trends in the warm (cold) day occurrence were positive (negative) only for six (three) of the nine considered sub-continental regions, simulated model trends are always positive (negative). This different behaviour suggests that simulated non-anthropogenic decadal variability is small relative to anthropogenic trends. Large-scale synoptic processes associated with European regional warm and cold peaks are also described and validated. Regional cold peaks are better reproduced than warm peaks, whose intensity accuracy is limited by other physical variables. Positive (negative) winter anomalies of sea and land surface temperature lead to summers with severe (weak) temperatures. These inter-annual anomalies are generated by a persistent pressure dipole over Europe. Regarding climate change, warm (cold) events will become more (less) frequent and longer (shorter). The number of warm days will largely rise and the number of cold days will dramatically decrease. The intensity of warm days will be particularly pronounced over Europe, given the projected summer drying in this region. However, according to the limited skill of the CNRM model, these results must be considered with caution.

  9. Vascular Cell Adhesion Molecule 1, Intercellular Adhesion Molecule 1, and Cluster of Differentiation 146 Levels in Patients with Type 2 Diabetes with Complications

    PubMed Central

    Saribal, Devrim; Yenmis, Guven; Guvenen, Guvenc

    2017-01-01

    Background Type 2 diabetes mellitus (T2DM) is a multisystemic, chronic disease accompanied by microvascular complications involving various complicated mechanisms. Intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and cluster of differentiation-146 (CD146) are mainly expressed by endothelial cells, and facilitate the adhesion and transmigration of immune cells, leading to inflammation. In the present study, we evaluated the levels of soluble adhesion molecules in patients with microvascular complications of T2DM. Methods Serum and whole blood samples were collected from 58 T2DM patients with microvascular complications and 20 age-matched healthy subjects. Levels of soluble ICAM-1 (sICAM-1) and soluble VCAM-1 (sVCAM-1) were assessed using enzyme-linked immunosorbent assay, while flow cytometry was used to determine CD146 levels. Results Serum sICAM-1 levels were lower in T2DM patients with microvascular complications than in healthy controls (P<0.05). No significant differences were found in sVCAM-1 and CD146 levels between the study and the control group. Although patients were subdivided into groups according to the type of microvascular complications that they experienced, cell adhesion molecule levels were not correlated with the complication type. Conclusion In the study group, most of the patients were on insulin therapy (76%), and 95% of them were receiving angiotensin-converting enzyme (ACE)-inhibitor agents. Insulin and ACE-inhibitors have been shown to decrease soluble adhesion molecule levels via various mechanisms, so we suggest that the decreased or unchanged levels of soluble forms of cellular adhesion molecules in our study group may have resulted from insulin and ACE-inhibitor therapy, as well as tissue-localized inflammation in patients with T2DM. PMID:28345319

  10. Sodium chloride in supercritical water as a function of density: potentials of mean force and an equation for the dissociation constant from 723 to 1073 K and from 0 to 0.9 g/cm(3).

    PubMed

    Liu, Wenbin; Wood, Robert H; Doren, Douglas J

    2008-06-19

    The potential of mean force (PMF) of sodium chloride in water has been calculated by using the ab initio classical free-energy perturbation method at five state points: at 973 K with densities of 0.2796, 0.0935, and 0.0101 g/cm (3) and at 723 K with densities of 0.0897 and 0.0098 g/cm (3). The method is based on a QM-MM model in which Na-H 2O, Cl-H 2O, and Na-Cl interactions are calculated by ab initio methods. The water-water interactions are from the polarizable TIP4P-FQ model. The logarithm of the dissociation constant (log K c) has been calculated from the PMF. These predictions, together with experimental measurements, were used to derive an equation for log K c at densities from 0 to 0.9 g/cm (3) and temperatures from 723 to 1073 K, as well as from 600 to 1073 K for densities from 0.29 g/cm (3) to 0.9 g/cm (3). Extrapolation of the present equation below 723 K for densities less than 0.29 g/cm (3) does not fit the experimental results. This is attributed to long-range changes in the local dielectric constant due to the high compressibility. Comparisons with previous predictions and simulations are presented.

  11. Complement activation and kidney injury molecule-1-associated proximal tubule injury in severe preeclampsia.

    PubMed

    Burwick, Richard M; Easter, Sarah Rae; Dawood, Hassan Y; Yamamoto, Hidemi S; Fichorova, Raina N; Feinberg, Bruce B

    2014-10-01

    Kidney injury with proteinuria is a characteristic feature of preeclampsia, yet the nature of injury in specific regions of the nephron is incompletely understood. Our study aimed to use existing urinary biomarkers to describe the pattern of kidney injury and proteinuria in pregnancies affected by severe preeclampsia. We performed a case-control study of pregnant women from Brigham and Women's Hospital from 2012 to 2013. We matched cases of severe preeclampsia (n=25) 1:1 by parity and gestational age to 2 control groups with and without chronic hypertension. Urinary levels of kidney injury molecule-1 and complement components (C3a, C5a, and C5b-9) were measured by enzyme-linked immunosorbent assay, and other markers (albumin, β2 microglobulin, cystatin C, epithelial growth factor, neutrophil gelatinase-associated lipocalin, osteopontin, and uromodulin) were measured simultaneously with a multiplex electrochemiluminescence assay. Median values between groups were compared with the Wilcoxon signed-rank test and correlations with Spearman correlation coefficient. Analysis of urinary markers revealed higher excretion of albumin and kidney injury molecule-1 and lower excretion of neutrophil gelatinase-associated lipocalin and epithelial growth factor in severe preeclampsia compared with chronic hypertension and healthy controls. Among subjects with severe preeclampsia, urinary excretion of complement activation products correlated most closely with kidney injury molecule-1, a specific marker of proximal tubule injury (C5a: r=0.60; P=0.001; and C5b-9: r=0.75; P<0.0001). Taken together, we describe a pattern of kidney injury in severe preeclampsia that is characterized by glomerular impairment and complement-mediated inflammation and injury, possibly localized to the proximal tubule in association with kidney injury molecule-1.

  12. Selective detection of sub-atto-molar Streptavidin in 10(13)-fold impure sample using photonic crystal nanolaser sensors.

    PubMed

    Hachuda, Shoji; Otsuka, Shota; Kita, Shota; Isono, Toshinari; Narimatsu, Michimasa; Watanabe, Keisuke; Goshima, Yoshio; Baba, Toshihiko

    2013-05-20

    Biosensors selectively detecting a very small amount of biomarker protein in human blood are desired for early and reliable diagnoses of severe diseases. This paper reports the detection of protein (streptavidin: SA) in ultra-low concentration, with an ultra-high selectivity against contaminants, using photonic crystal nanolasers. For biotin-modified nanolasers in pure water with SA, an extremely-low detection limit of 16 zM is evaluated. Even in a mixture with 1 μM bovine serum albumin as the contaminant, 100 zM SA is detected, meaning a selectivity of 10(13). These are remarkable capabilities that are promising for practical biosensing in the medical applications mentioned above.

  13. Targeting sites of inflammation: intercellular adhesion molecule-1 as a target for novel inflammatory therapies

    PubMed Central

    Hua, Susan

    2013-01-01

    Targeted drug delivery to sites of inflammation will provide effective, precise, and safe therapeutic interventions for treatment of diverse disease conditions, by limiting toxic side effects and/or increasing drug action. Disease-site targeting is believed to play a major role in the enhanced efficacy observed for a variety of drugs when formulated inside lipid vesicles. This article will focus on the factors and mechanisms involved in drug targeting to sites of inflammation and the importance of cell adhesion molecules, in particular intercellular adhesion molecule-1, in this process. PMID:24109453

  14. Laboratory-Scale Column Testing Using IONSIV IE-911 for Removing Cesium from Acidic Tank Waste Simulant. 2: Determination of Cesium Exchange Capacity and Effective Mass Transfer Coefficient from a 500-cm3 Column Experiement

    SciTech Connect

    T.J. Tranter; R.D. Tillotson; T.A. Todd

    2005-04-01

    A semi-scale column test was performed using a commercial form of crystalline silicotitanate (CST) for removing radio-cesium from a surrogate acidic tank solution, which represents liquid waste stored at the Idaho National Engineering and Environmental Laboratory (INEEL). The engineered form of CST ion exchanger, known as IONSIVtmIE-911 (UOP, Mt. Laurel,NJ, USA), was tested in a 500-cm3 column to obtain a cesium breakthrough curve. The cesium exchange capacity of this column matched that obtained from previous testing with a 15-mc3 column. A numerical algorithm using implicit finite difference approximations was developed to solve the governing mass transport equations for the CST columns. An effective mass transfer coefficient was derived from solving these equations for previously reported 15 cm3 tests. The effective mass transfer coefficient was then used to predict the cesium breakthrough curve for the 500-cm3 column and compared to the experimental data reported in this paper. The calculated breakthrough curve showed excellent agreement with the data from the 500-cm3 column even though the interstitial velocity was a factor of two greater. Thus, this approach should provide a reasonable method for scale up to larger columns for treating actual tank waste.

  15. Toxoplasma gondii tachyzoites cross retinal endothelium assisted by intercellular adhesion molecule-1 in vitro.

    PubMed

    Furtado, João M; Bharadwaj, Arpita S; Chipps, Timothy J; Pan, Yuzhen; Ashander, Liam M; Smith, Justine R

    2012-10-01

    Retinal infection is the most common clinical manifestation of toxoplasmosis. The route by which circulating Toxoplasma gondii tachyzoites cross the vascular endothelium to enter the human retina is unknown. Convincing studies using murine encephalitis models have strongly implicated leukocyte taxis as one pathway used by the parasite to access target organs. To establish whether tachyzoites might also interact directly with vascular endothelium, we populated a transwell system with human ocular endothelial cells. Human retinal endothelial monolayers permitted transmigration of tachyzoites of RH and three natural isolate strains. Antibody blockade of intercellular adhesion molecule-1 significantly reduced this migration, but did not impact tachyzoite movement across an endothelial monolayer derived from the choroid, which lies adjacent to the retina within the eye. In demonstrating that tachyzoites are capable of independent migration across human vascular endothelium in vitro, this study carries implications for the development of therapeutics aimed at preventing access of T. gondii to the retina.

  16. Critical roles of co-activation receptor DNAX accessory molecule-1 in natural killer cell immunity

    PubMed Central

    Xiong, Peng; Sang, Hai-Wei; Zhu, Min

    2015-01-01

    Natural killer (NK) cells, which can exert early and powerful anti-tumour and anti-viral responses, are important components of the innate immune system. DNAX accessory molecule-1 (DNAM-1) is an activating receptor molecule expressed on the surface of NK cells. Recent findings suggest that DNAM-1 is a critical regulator of NK cell biology. DNAM-1 is involved in NK cell education and differentiation, and also plays a pivotal role in the development of cancer, viral infections and immune-related diseases. However, tumours and viruses have developed multiple mechanisms to evade the immune system. They are able to impair DNAM-1 activity by targeting the DNAM-1 receptor–ligand system. We have reviewed the roles of DNAM-1, and its biological functions, with respect to NK cell biology and DNAM-1 chimeric antigen receptor-based immunotherapy. PMID:26235210

  17. MORPHEUS' MOLECULE1 is required to prevent aberrant RNA transcriptional read-through in Arabidopsis.

    PubMed

    Zhou, Yue; Zhang, Jun; Lin, Huixin; Guo, Guangqin; Guo, Yan

    2010-11-01

    Several pathways function to remove aberrant mRNA in eukaryotic cells; however, the exact mechanisms underlying the restriction of aberrant mRNA transcription are poorly understood. In this study, we found that MORPHEUS' MOLECULE1 (MOM1) is a key component of this regulatory machinery. The Arabidopsis (Arabidopsis thaliana) mom1-44 mutation was identified by luciferase imaging in transgenic plants harboring a cauliflower mosaic virus 35S promoter-LUCIFERASE transgene lacking the 3'-untranslated region. In the mom1-44 mutant, transcriptional read-though occurred in genes with an aberrant RNA structure. Analysis of an RNA-dependent RNA polymerase2 mom1 double mutant revealed that the RNA-directed DNA methylation pathway is not involved in this regulatory process. Moreover, the prevention of aberrant mRNA transcriptional read-through by MOM1 is gene locus and transgene copy number independent.

  18. Absence of Widespread Psychosocial and Cognitive Effects of School-Based Music Instruction in 10-13-Year-Old Students

    ERIC Educational Resources Information Center

    Rickard, Nikki S.; Bambrick, Caroline J.; Gill, Anneliese

    2012-01-01

    Previous studies demonstrate that private music training has benefits which may transfer to other domains, including verbal memory, intelligence and self-esteem. The current paper reports on the impact of an increase in school-based music training on a range of cognitive and psychosocial measures for 10-13-year-olds in two independent studies. In…

  19. Proceedings of the Annual International Conference of the Association for the Education of Teachers in Science (Charlotte, North Carolina, January 10-13, 2002).

    ERIC Educational Resources Information Center

    Rubba, Peter A., Ed.; Rye, James A., Ed.; DiBiase, Warren J., Ed.; Crawford, Barbara A., Ed.

    This document contains the proceedings of the 2002 Annual International Conference of the Association for the Education of Teachers in Science which was held in Charlotte, North Carolina, January 10-13, 2002. Papers include: (1) "Teaching Science Methods Courses with Web-Enhanced Activities" (Alec M. Bodzin); (2) "How Is Your Lawnmower Working?…

  20. Role of Intercellular Adhesion Molecule-1 in Radiation-Induced Brain Injury

    SciTech Connect

    Wu, K.-L.; Tu Ba; Li Yuqing; Wong, C. Shun

    2010-01-15

    Purpose: To determine the role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of brain injury after irradiation (IR). Methods and Materials: We assessed the expression of ICAM-1 in mouse brain after cranial IR and determined the histopathologic and behavioral changes in mice that were either wildtype (+/+) or knockout (-/-) of the ICAM-1 gene after IR. Results: There was an early dose-dependent increase in ICAM-1 mRNA and protein expression after IR. Increased ICAM-1 immunoreactivity was observed in endothelia and glia of ICAM-1+/+ mice up to 8 months after IR. ICAM-1-/- mice showed no expression. ICAM-1+/+ and ICAM-1-/- mice showed similar vascular abnormalities at 2 months after 10-17 Gy, and there was evidence for demyelination and inhibition of hippocampal neurogenesis at 8 months after 10 Gy. After 10 Gy, irradiated ICAM-1+/+ and ICAM-1-/- mice showed similar behavioral changes at 2-6 months in open field, light-dark chamber, and T-maze compared with age-matched genotype controls. Conclusion: There is early and late upregulation of ICAM-1 in the vasculature and glia of mouse brain after IR. ICAM-1, however, does not have a causative role in the histopathologic injury and behavioral dysfunction after moderate single doses of cranial IR.

  1. Kidney injury molecule-1 is an early biomarker of cadmium nephrotoxicity

    PubMed Central

    Prozialeck, WC; Vaidya, VS; Liu, J; Waalkes, MP; Edwards, JR; Lamar, PC; Bernard, AM; Dumont, X; Bonventre, JV

    2009-01-01

    Cadmium (Cd) exposure results in injury to the proximal tubule characterized by polyuria and proteinuria. Kidney injury molecule-1 (Kim-1) is a transmembrane glycoprotein not normally detected in the mature kidney, but is upregulated and shed into the urine following nephrotoxic injury. In this study, we determine if Kim-1 might be a useful early biomarker of Cd nephrotoxicity. Male Sprague-Dawley rats were given daily injections of Cd for up to 12 weeks. Weekly urine samples were analyzed for Kim-1, protein, creatinine, metallothionein, and Clara cell protein CC-16. Significant levels of Kim-1 were detected in the urine by 6 weeks and continued to increase throughout the treatment period. This appearance of Kim-1 occurred 4-5 weeks before the onset of proteinuria, and 1-3 weeks before the appearance of metallothionein and CC-16. Higher doses of Cd gave rise to higher Kim-1 excretion. Reverse transcriptase-polymerase chain reaction (RT-PCR) expression analysis showed that Kim-1 transcript levels were increased after 6 weeks at the low dose of Cd. Immunohistochemical analysis showed that Kim-1 was present in proximal tubule cells of the Cd-treated rats. Our results suggest that Kim-1 may be a useful biomarker of early stages of Cd-induced proximal tubule injury. PMID:17687258

  2. Reduced Hepatic Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1 Level in Obesity

    PubMed Central

    Heinrich, Garrett; Muturi, Harrison T.; Rezaei, Khadijeh; Al-Share, Qusai Y.; DeAngelis, Anthony M.; Bowman, Thomas A.; Ghadieh, Hilda E.; Ghanem, Simona S.; Zhang, Deqiang; Garofalo, Robert S.; Yin, Lei; Najjar, Sonia M.

    2017-01-01

    Impairment of insulin clearance is being increasingly recognized as a critical step in the development of insulin resistance and metabolic disease. The carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) promotes insulin clearance. Null deletion or liver-specific inactivation of Ceacam1 in mice causes a defect in insulin clearance, insulin resistance, steatohepatitis, and visceral obesity. Immunohistological analysis revealed reduction of hepatic CEACAM1 in obese subjects with fatty liver disease. Thus, we aimed to determine whether this occurs at the hepatocyte level in response to systemic extrahepatic factors and whether this holds across species. Northern and Western blot analyses demonstrate that CEACAM1 mRNA and protein levels are reduced in liver tissues of obese individuals compared to their lean age-matched counterparts. Furthermore, Western analysis reveals a comparable reduction of CEACAM1 protein in primary hepatocytes derived from the same obese subjects. Similar to humans, Ceacam1 mRNA level, assessed by quantitative RT-PCR analysis, is significantly reduced in the livers of obese Zucker (fa/fa, ZDF) and Koletsky (f/f) rats relative to their age-matched lean counterparts. These studies demonstrate that the reduction of hepatic CEACAM1 in obesity occurs at the level of hepatocytes and identify the reduction of hepatic CEACAM1 as a common denominator of obesity across multiple species.

  3. Intercellular Adhesion Molecule-1 Expression by Skeletal Muscle Cells Augments Myogenesis

    PubMed Central

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

    2014-01-01

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast-myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube-myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube-myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. PMID:25281303

  4. Polymorphisms in the intercellular adhesion molecule 1 gene and cancer risk: a meta-analysis

    PubMed Central

    Tang, Weifeng; Wang, Yafeng; Chen, Yuanmei; Gu, Haiyong; Chen, Shuchen; Kang, Mingqiang

    2015-01-01

    Objectives: The correlation between intercellular adhesion molecule 1 (ICAM-1) common polymorphisms (rs5498 A>G and rs3093030 C>T) and cancer susceptibility has been explored in various ethnic groups and different cancer types; however, these investigations have yielded contradictory results. To address the relationship more precisely, we performed this meta-analysis. Design and methods: EmBase, PubMed and China National Knowledge Infrastructure (CNKI) databases were searched by two authors independently for eligible publications before April 8, 2015. Random-effects or fixed-effects model was harnessed to calculate the pooled odds ratios (ORs) and 95% confidence intervals (CIs) when appropriate. Results: The result suggested that the ICAM-1 rs5498 A>G polymorphism is not associated with cancer susceptibility in overall cancer. In a stratified analysis by ethnicity, a significant increased cancer risk was identified among Asians, but the inverse association was found among Caucasians. In a stratified analysis by cancer type, ICAM-1 rs5498 A>G polymorphism was associated with a significantly increased risk of oral cancer, but with protection from colorectal cancer and melanoma. ICAM-1 rs3093030 C>T polymorphism is not correlated with cancer susceptibility. Conclusions: In summary, this meta-analysis highlights that the ICAM-1 rs5498 A>G polymorphism probably contributes to decreased susceptibility to cancer, especially in Caucasians, in melanoma and colorectal cancer subgroup, but it may be a risk factor for oral cancer and Asians. PMID:26550112

  5. Kidney Injury Molecule-1 and Cardiovascular Diseases: From Basic Science to Clinical Practice

    PubMed Central

    Medić, Branislava; Rovčanin, Branislav; Basta Jovanović, Gordana; Radojević-Škodrić, Sanja; Prostran, Milica

    2015-01-01

    Despite the recent findings concerning pathogenesis and novel therapeutic strategies, cardiovascular disease (CVD) still stays the leading cause of morbidity and mortality in patients with renal dysfunction, especially acute kidney injury (AKI). Early detection of patients with impaired renal function with cardiovascular risk may help ensure more aggressive treatment and improve clinical outcome. Kidney injury molecule-1 (KIM-1) is a new, promising marker of kidney damage which is currently the focus of countless studies worldwide. Some recent animal and human studies established KIM-1 as an important marker of acute tubular necrosis (ATN) and reliable predictor of development and prognosis of AKI. Food and Drug Administration (FDA) in USA acclaimed KIM-1 as an AKI biomarker for preclinical drug development. Recent data suggest the importance of monitoring of KIM-1 for early diagnosis and clinical course not only in patients with various forms of AKI and other renal diseases but also in patients with cardiorenal syndrome, heart failure, cardiopulmonary bypass, cardiothoracic surgical interventions in the pediatric emergency setting, and so forth. The aim of this review article is to summarize the literature data concerning KIM-1 as a potential novel marker in the early diagnosis and prediction of clinical outcome of certain cardiovascular diseases. PMID:26697493

  6. Kidney injury molecule-1: more than just an injury marker of tubular epithelial cells?

    PubMed

    Lim, Ai Ing; Tang, Sydney C W; Lai, Kar Neng; Leung, Joseph C K

    2013-05-01

    Regardless of the original causes and etiology, the progression to renal function declines follows a final common pathway associated with tubulointerstitial injury, in which the proximal tubular epithelial cells (PTEC) are instrumental. Kidney injury molecule-1 (KIM-1) is an emerging biomarker, and its expression and release are induced in PTEC upon injury. KIM-1 plays the role as a double-edged sword and implicates in the process of kidney injury and healing. Expression of KIM-1 is also associated with tubulointerstitial inflammation and fibrosis. More importantly, KIM-1 expressing PTEC play the role as the residential phagocytes, contribute to the removal of apoptotic cells and facilitate the regeneration of injured tubules. The precise mechanism of KIM-1 and its sheded ectodomain on restoration of tubular integrity after injury is not fully understood. Other than PTEC, macrophages (Mø) also implicate in tubular repair. Understanding the crosstalk between Mø and the injured PTEC is essential for designing appropriate methods for controlling the sophisticated machinery in tubular regeneration and healing. This article will review the current findings of KIM-1, beginning with its basic structure, utility as a biomarker, and possible functions, with focus on the role of KIM-1 in regeneration and healing of injured PTEC.

  7. Effect of Cell Adhesion Molecule 1 Expression on Intracellular Granule Movement in Pancreatic α Cells.

    PubMed

    Yokawa, Satoru; Furuno, Tadahide; Suzuki, Takahiro; Inoh, Yoshikazu; Suzuki, Ryo; Hirashima, Naohide

    2016-09-01

    Although glucagon secreted from pancreatic α cells plays a role in increasing glucose concentrations in serum, the mechanism regulating glucagon secretion from α cells remains unclear. Cell adhesion molecule 1 (CADM1), identified as an adhesion molecule in α cells, has been reported not only to communicate among α cells and between nerve fibers, but also to prevent excessive glucagon secretion from α cells. Here, we investigated the effect of CADM1 expression on the movement of intracellular secretory granules in α cells because the granule transport is an important step in secretion. Spinning disk microscopic analysis showed that granules moved at a mean velocity of 0.236 ± 0.010 μm/s in the mouse α cell line αTC6 that expressed CADM1 endogenously. The mean velocity was significantly decreased in CADM1-knockdown (KD) cells (mean velocity: 0.190 ± 0.016 μm/s). The velocity of granule movement decreased greatly in αTC6 cells treated with the microtubule-depolymerizing reagent nocodazole, but not in αTC6 cells treated with the actin-depolymerizing reagent cytochalasin D. No difference in the mean velocity was observed between αTC6 and CADM1-KD cells treated with nocodazole. These results suggest that intracellular granules in pancreatic α cells move along the microtubule network, and that CADM1 influences their velocity.

  8. The Prion Protein Controls Polysialylation of Neural Cell Adhesion Molecule 1 during Cellular Morphogenesis

    PubMed Central

    Mehrabian, Mohadeseh; Brethour, Dylan; Wang, Hansen; Xi, Zhengrui; Rogaeva, Ekaterina; Schmitt-Ulms, Gerold

    2015-01-01

    Despite its multi-faceted role in neurodegenerative diseases, the physiological function of the prion protein (PrP) has remained elusive. On the basis of its evolutionary relationship to ZIP metal ion transporters, we considered that PrP may contribute to the morphogenetic reprogramming of cells underlying epithelial-to-mesenchymal transitions (EMT). Consistent with this hypothesis, PrP transcription increased more than tenfold during EMT, and stable PrP-deficient cells failed to complete EMT in a mammalian cell model. A global comparative proteomics analysis identified the neural cell adhesion molecule 1 (NCAM1) as a candidate mediator of this impairment, which led to the observation that PrP-deficient cells fail to undergo NCAM1 polysialylation during EMT. Surprisingly, this defect was caused by a perturbed transcription of the polysialyltransferase ST8SIA2 gene. Proteomics data pointed toward β-catenin as a transcriptional regulator affected in PrP-deficient cells. Indeed, pharmacological blockade or siRNA-based knockdown of β-catenin mimicked PrP-deficiency in regards to NCAM1 polysialylation. Our data established the existence of a PrP-ST8SIA2-NCAM signaling loop, merged two mature fields of investigation and offer a simple model for explaining phenotypes linked to PrP. PMID:26288071

  9. Down syndrome cell adhesion molecule 1: testing for a role in insect immunity, behaviour and reproduction.

    PubMed

    Peuß, Robert; Wensing, Kristina U; Woestmann, Luisa; Eggert, Hendrik; Milutinović, Barbara; Sroka, Marlene G U; Scharsack, Jörn P; Kurtz, Joachim; Armitage, Sophie A O

    2016-04-01

    Down syndrome cell adhesion molecule 1 (Dscam1) has wide-reaching and vital neuronal functions although the role it plays in insect and crustacean immunity is less well understood. In this study, we combine different approaches to understand the roles that Dscam1 plays in fitness-related contexts in two model insect species. Contrary to our expectations, we found no short-term modulation of Dscam1 gene expression after haemocoelic or oral bacterial exposure in Tribolium castaneum, or after haemocoelic bacterial exposure in Drosophila melanogaster. Furthermore, RNAi-mediated Dscam1 knockdown and subsequent bacterial exposure did not reduce T. castaneum survival. However, Dscam1 knockdown in larvae resulted in adult locomotion defects, as well as dramatically reduced fecundity in males and females. We suggest that Dscam1 does not always play a straightforward role in immunity, but strongly influences behaviour and fecundity. This study takes a step towards understanding more about the role of this intriguing gene from different phenotypic perspectives.

  10. Integrin engagement mediates tyrosine dephosphorylation on platelet-endothelial cell adhesion molecule 1.

    PubMed Central

    Lu, T T; Yan, L G; Madri, J A

    1996-01-01

    Platelet-endothelial cell adhesion molecule 1 (PECAM-1, CD31) is a 130-kDa member of the immunoglobulin gene superfamily expressed on endothelial cells, platelets, neutrophils, and monocytes and plays a role during endothelial cell migration. Phosphoamino acid analysis and Western blot analysis with anti-phosphotyrosine antibody show that endothelial PECAM-1 is tyrosine-phosphorylated. Phosphorylation is decreased with endothelial cell migration on fibronectin and collagen and with cell spreading on fibronectin but not on plastic. Cell adhesion on anti-integrin antibodies is also able to specifically induce PECAM-1 dephosphorylation while concurrently inducing pp125 focal adhesion kinase phosphorylation. Inhibition of dephosphorylation with sodium orthovanadate suggests that this effect is at least partially mediated by phosphatase activity. Tyr-663 and Tyr-686 are identified as potential phosphorylation sites and mutated to phenylalanine. When expressed, both mutants show reduced PECAM-1 phosphorylation but Phe-686 mutants also show significant reversal of PECAM-1-mediated inhibition of cell migration and do not localize PECAM-1 to cell borders. Our results suggest that beta 1-integrin engagement can signal to dephosphorylate PECAM-1 and that this signaling pathway may play a role during endothelial cell migration. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:8876219

  11. Lack of Platelet Endothelial Cell Adhesion Molecule-1 Attenuates Foreign Body Inflammation because of Decreased Angiogenesis

    PubMed Central

    Solowiej, Anna; Biswas, Purba; Graesser, Donnasue; Madri, Joseph A.

    2003-01-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1, CD31) is a 130-kd member of the immunoglobulin superfamily of proteins, expressed on endothelial cells, leukocytes, and platelets. Antibody-blocking studies have implicated it in modulating leukocyte transmigration and angiogenesis. However, the generation of the PECAM-1 knockout mouse has shown that its function can be compensated for by similarly acting proteins because most acute inflammatory models proceed in a comparable manner in wild-type and knockout animals. We decided to examine the function of PECAM-1 in the chronic process of foreign body inflammation. We show that PECAM-1-deficient mice exhibit attenuated neutrophil infiltration in and around a subcutaneous polyvinyl acetyl implant. Bone marrow engraftment studies indicate that the lack of CD31 expression on the endothelium determines the diminished leukocyte accumulation in the knockout implants. Specifically, we find that decreased angiogenesis (as manifested by lower vessel density, decreased hemoglobin content, and less laminin deposition) correlates with lower neutrophil accumulation in the knockout animals. This study indicates that the absence of endothelial PECAM-1 results in decreased angiogenesis and therefore in diminished delivery of leukocytes to the foreign body implants. PMID:12598328

  12. Control of islet intercellular adhesion molecule-1 expression by interferon-alpha and hypoxia.

    PubMed

    Chakrabarti, D; Huang, X; Beck, J; Henrich, J; McFarland, N; James, R F; Stewart, T A

    1996-10-01

    The ability of interferon-alpha (IFN-alpha) to induce the adhesion molecules that characterize the islets of patients with type I diabetes has been investigated. We have found that all tested recombinant IFN-as will induce major histocompatibility complex (MHC) class I on arterial endothelial cells. Some but not all IFN-as will induce intercellular adhesion molecule-1 (ICAM-1). However, there is only a transient and modest increase in VCAM on arterial endothelial cells. IFN-alpha has very little effect on endothelial MHC class II expression but will induce these proteins on monocytes. Thus, there is a close concordance between the biological actions of IFN-alpha and the appearance of those adhesion molecules induced in the islets of patients with type I diabetes. IFN-alpha is also produced in normal human islets during short-term cultures, probably as a result of the ischemia present at the center of the islet. This induction of IFN-alpha by hypoxia may explain the previously reported spontaneous induction of ICAM-1 in human islets and may also be a contributing factor to the failure of islet grafts.

  13. The Prion Protein Controls Polysialylation of Neural Cell Adhesion Molecule 1 during Cellular Morphogenesis.

    PubMed

    Mehrabian, Mohadeseh; Brethour, Dylan; Wang, Hansen; Xi, Zhengrui; Rogaeva, Ekaterina; Schmitt-Ulms, Gerold

    2015-01-01

    Despite its multi-faceted role in neurodegenerative diseases, the physiological function of the prion protein (PrP) has remained elusive. On the basis of its evolutionary relationship to ZIP metal ion transporters, we considered that PrP may contribute to the morphogenetic reprogramming of cells underlying epithelial-to-mesenchymal transitions (EMT). Consistent with this hypothesis, PrP transcription increased more than tenfold during EMT, and stable PrP-deficient cells failed to complete EMT in a mammalian cell model. A global comparative proteomics analysis identified the neural cell adhesion molecule 1 (NCAM1) as a candidate mediator of this impairment, which led to the observation that PrP-deficient cells fail to undergo NCAM1 polysialylation during EMT. Surprisingly, this defect was caused by a perturbed transcription of the polysialyltransferase ST8SIA2 gene. Proteomics data pointed toward β-catenin as a transcriptional regulator affected in PrP-deficient cells. Indeed, pharmacological blockade or siRNA-based knockdown of β-catenin mimicked PrP-deficiency in regards to NCAM1 polysialylation. Our data established the existence of a PrP-ST8SIA2-NCAM signaling loop, merged two mature fields of investigation and offer a simple model for explaining phenotypes linked to PrP.

  14. Down syndrome cell adhesion molecule 1: testing for a role in insect immunity, behaviour and reproduction

    PubMed Central

    Wensing, Kristina U.; Eggert, Hendrik; Scharsack, Jörn P.

    2016-01-01

    Down syndrome cell adhesion molecule 1 (Dscam1) has wide-reaching and vital neuronal functions although the role it plays in insect and crustacean immunity is less well understood. In this study, we combine different approaches to understand the roles that Dscam1 plays in fitness-related contexts in two model insect species. Contrary to our expectations, we found no short-term modulation of Dscam1 gene expression after haemocoelic or oral bacterial exposure in Tribolium castaneum, or after haemocoelic bacterial exposure in Drosophila melanogaster. Furthermore, RNAi-mediated Dscam1 knockdown and subsequent bacterial exposure did not reduce T. castaneum survival. However, Dscam1 knockdown in larvae resulted in adult locomotion defects, as well as dramatically reduced fecundity in males and females. We suggest that Dscam1 does not always play a straightforward role in immunity, but strongly influences behaviour and fecundity. This study takes a step towards understanding more about the role of this intriguing gene from different phenotypic perspectives. PMID:27152227

  15. Stromal interaction molecule 1 regulates growth, cell cycle, and apoptosis of human tongue squamous carcinoma cells.

    PubMed

    Cui, Xiaobo; Song, Laixiao; Bai, Yunfei; Wang, Yaping; Wang, Boqian; Wang, Wei

    2017-04-30

    Oral tongue squamous cell carcinoma (OTSCC) is the most common type of oral carcinomas. However, the molecular mechanism by which OTSCC developed is not fully identified. Stromal interaction molecule 1 (STIM1) is a transmembrane protein, mainly located in the endoplasmic reticulum (ER). STIM1 is involved in several types of cancers. Here, we report that STIM1 contributes to the development of human OTSCC. We knocked down STIM1 in OTSCC cell line Tca-8113 with lentivirus-mediated shRNA and found that STIM1 knockdown repressed the proliferation of Tca-8113 cells. In addition, we also showed that STIM1 deficiency reduced colony number of Tca-8113 cells. Knockdown of STIM1 repressed cells to enter M phase of cell cycle and induced cellular apoptosis. Furthermore, we performed microarray and bioinformatics analysis and found that STIM1 was associated with p53 and MAPK pathways, which may contribute to the effects of STIM1 on cell growth, cell cycle, and apoptosis. Finally, we confirmed that STIM1 controlled the expression of MDM2, cyclin-dependent kinase 4 (CDK4), and growth arrest and DNA damage inducible α (GADD45A) in OTSCC cells. In conclusion, we provide evidence that STIM1 contributes to the development of OTSCC partially through regulating p53 and MAPK pathways to promote cell cycle and survival.

  16. Epigenetic silencing of endogenous repetitive sequences by MORPHEUS' MOLECULE1 in Arabidopsis thaliana.

    PubMed

    Habu, Yoshiki

    2010-10-01

    Morpheus' molecule1 (MOM1) is a plant-specific epigenetic regulator of transcriptional gene silencing. Mutants of MOM1 release silencing of subsets of endogenous repetitive elements and transgenes without affecting their cytosine methylation status. Although MOM1 is evolutionarily related to chromodomain helicase DNA binding protein3 (CHD3), a family of chromatin remodeling proteins involved in repression of gene expression, MOM1 does not carry the functional ATPase/helicase domain essential for chromatin remodeling activity, and therefore, its mode of action is unknown. We recently performed a genome-wide survey for endogenous targets silenced by MOM1 and identified loci that are concentrated around centromeres and rich in sequences homologous to the 24-nt small interfering RNAs (siRNAs) that accumulate in wild type plants. Further and independent analyses indicated that the degree of contribution of MOM1 to maintenance of the silent states varies in different loci and that other silencing machineries, including those in the RNA-directed DNA methylation (RdDM) pathway, interact genetically with MOM1. In this short article, I review what we know about MOM1 and discuss its possible functions in silencing through examination of other silencing factors that interact genetically with MOM1.

  17. Solubility of chlorargyrite (AgCl(cr./l.)) in water: New experimental data and a predictive model valid for a wide range of temperatures (273-873 K) and water densities (0.01-1 g·cm-3)

    NASA Astrophysics Data System (ADS)

    Akinfiev, Nikolay N.; Zotov, Alexander V.

    2016-04-01

    The solubility of chlorargyrite, AgCl(cr./l.), in pure water at 623, 673 and 753 (±2) K as a function of pressure in a wide range aqueous densities (0.01-0.7 g·cm-3) was determined using various experimental approaches. Combined theoretical quantum chemistry simulations of Ag speciation and structure with a recently developed equation of state (EoS) for aqueous neutral species (Akinfiev and Diamond, 2003) were applied to describe published and newly made AgCl(cr./l.) solubility measurements in water. The use of the employed EoS for AgCl(H2O)(aq) cluster is found out to provide a good description of the whole set of experimental measurements in a wide range of temperatures (273-753 K), water densities (0.01-0.7 g·cm-3), and pressures of 0.1-100 MPa. Also, the proposed AgCl(H2O)(aq) thermodynamic description is proved to be valid for a dense aqueous fluid (0.7-1 g·cm-3) at 273-623 K and saturation water pressure. Although silver obviously shows greater affinity to dense aqueous fluid, AgCl hydration in the vapour phase is demonstrated to be also significant. A model extrapolation to magmatic conditions predicts an appreciable silver content even in low density fluids, thus supporting the hypothesis of metal transport with vapour.

  18. Involvement of oxidative stress and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in inflammatory bowel disease

    PubMed Central

    Tanida, Satoshi; Mizoshita, Tsutomu; Mizushima, Takashi; Sasaki, Makoto; Shimura, Takaya; Kamiya, Takeshi; Kataoka, Hiromi; Joh, Takashi

    2011-01-01

    The pathophysiology of inflammatory bowel disease involves excessive immune effects of inflammatory cells against gut microbes. In genetically predisposed individuals, these effects are considered to contribute to the initiation and perpetuation of mucosal injury. Oxidative stress is a fundamental tissue-destructive mechanisms that can occur due to the reactive oxygen species and reactive nitrogen metabolites which are released in abundance from numerous inflammatory cells that have extravasated from lymphatics and blood vessels to the lamina propria. This extravasation is mediated by interactions between adhesion molecules including mucosal addressin cell adhesion molecule-1 and vascular cell adhesion molecule-1 on the surface of lymphocytes or neutrophils and their ligands on endothelial cells. Thus, reactive oxygen species and adhesion molecules play an important role in the development of inflammatory bowel disease. The present review focuses on the involvement of oxidative stress and adhesion molecules, in particular mucosal addressin cell adhesion molecule-1, in inflammatory bowel disease. PMID:21373262

  19. Differential up-regulation of circulating soluble and endothelial cell intercellular adhesion molecule-1 in mice.

    PubMed Central

    Komatsu, S.; Flores, S.; Gerritsen, M. E.; Anderson, D. C.; Granger, D. N.

    1997-01-01

    Although circulating levels of soluble intercellular adhesion molecule-1 (sICAM-1) are frequently used as an indicator of the severity of different immune, inflammatory, or neoplastic diseases, little is known about the factors that govern plasma sICAM-1 concentration and its relationship to the membranous form of ICAM-1 (mICAM-1) expressed on vascular endothelial cells. Plasma sICAM-1 concentration (measured by enzyme-linked immunosorbent assay) and mICAM-1 expression (measured using the dual radiolabeled monoclonal antibody technique) in different vascular beds (eg, lung, small intestine, and spleen) were monitored in wild-type (C57BL) and ICAM-1-deficient mice, before and after administration of tumor necrosis factor (TNF)-alpha. In wild-type mice, TNF-alpha elicited time-dependent increases in lung and intestine mICAM-1 (plateau achieved at 12 hours), with a corresponding increase in plasma sICAM-1 (peaked at 5 hours and then declined). The initial increases in mICAM-1 and pulmonary leukocyte sequestration (measured as lung myeloperoxidase activity) induced by TNF-alpha preceded any detectable elevation in sICAM-1. In ICAM-1-deficient mice, plasma sICAM-1 was reduced by approximately 70%, with > 95% reductions of mICAM-1 in lung and intestine, and > 75% reduction in splenic accumulation of anti-ICAM-1 antibody. Although TNF-alpha doubled plasma sICAM-1 in ICAM-1-deficient mice, mICAM-1 was unaffected in all tissues. Either splenectomy or pretreatment with cycloheximide resulted in an attenuated TNF-induced increase in sICAM-1, without affecting mICAM-1 expression. These findings indicate that plasma sICAM-1 concentration does not accurately reflect the level of ICAM-1 expression on endothelial cells in different vascular beds. PMID:9212746

  20. Intercellular Adhesion Molecule-1 (ICAM-1) Polymorphisms and Cancer Risk: A Meta-Analysis

    PubMed Central

    CHENG, Daye; LIANG, Bin

    2015-01-01

    Background: Intercellular adhesion molecule-1 (ICAM-1) Lys469Glu (K469E) polymorphism and Gly 241Arg (G241R) polymorphism might play important roles in cancer development and progression. However, the results of previous studies are inconsistent. The aim of this study was to evaluate the association between ICAM-1 K469E and G241R polymorphisms and the risk of cancer by meta-analysis. Methods: A comprehensive literature search (last search updated in November 2013) was conducted to identify case-control studies that investigated the association between ICAM-1 K469E and G241R polymorphisms and cancer risk. Results: A total of 18 case-control studies for ICAM-1 polymorphisms were included in the meta-analysis, including 4,844 cancer cases and 5,618 healthy controls. For K469E polymorphism, no significant association was found between K469E polymorphism and cancer risk. However, subgroup analysis by ethnicity revealed one genetic comparison (GG vs. AA) presented the relationship with cancer risk in Asian subgroup, and two genetic models (GG+GA vs. AA and GA vs. AA) in European subgroup, respectively. For G241R polymorphism, G241R polymorphism was significantly association with cancer risk in overall analysis. The subgroup analysis by ethnicity showed that G241R polymorphism was significantly associated with cancer risk in European subgroup. Conclusion: ICAM-1 G241R polymorphism might be associated with cancer risk, especially in European populations, but the results doesn’t support ICAM-1 K469E polymorphism as a risk factor for cancer. PMID:26284202

  1. Intercellular adhesion molecule-1 (ICAM-1) expression is upregulated in autoimmune murine lupus nephritis.

    PubMed Central

    Wuthrich, R. P.; Jevnikar, A. M.; Takei, F.; Glimcher, L. H.; Kelley, V. E.

    1990-01-01

    Intercellular adhesion molecule-1 (ICAM-1) is a cell-surface protein regulating interactions among immune cells. To determine whether altered expression of ICAM-1 occurs in autoimmune lupus nephritis, we studied ICAM-1 expression in kidneys of normal and autoimmune MRL-lpr and (NZBX NZW)F1 (NZB/W) mice. By immunoperoxidase staining, ICAM-1 is constitutively expressed at low levels in proximal tubules (PT), endothelium and interstitial cells in normal C3H/FeJ mice. In nephritic MRL-lpr and NZB/W kidneys, staining for ICAM-1 is increased in the PT, particularly in the brush border, and is prominent in the glomerular mesangium and the endothelium of large vessels. By Western blot analysis, ICAM-1 is not detected in the urine of normal BALB/c and C3H/FeJ or autoimmune MRL-lpr. By Northern blot analysis, nephritic MRL-lpr and NZB/W have a two- to fivefold increase in steady state levels of ICAM-1 transcripts in the kidney as compared with normal or prenephritic mice. This is paralleled by an increase in MHC class II transcripts. In cultured PT cells, ICAM-1 is expressed at basal levels in PT and is increased by the cytokines interferon-gamma, IL-1 alpha, and TNF-alpha. Thus cytokine-mediated upregulation of ICAM-1 in lupus nephritis may promote interaction of immune cells with renal tissue. The predominant apical expression of ICAM-1 opposite to the basolateral Ia expression suggests a novel role for this adhesion molecule in PT. Images Figure 1 Figure 2 Figure 3 Figure 6 Figure 7 PMID:1968316

  2. R-Ras Regulates Murine T Cell Migration and Intercellular Adhesion Molecule-1 Binding

    PubMed Central

    Yan, Xiaocai; Yan, Mingfei; Guo, Yihe; Singh, Gobind; Chen, Yuhong; Yu, Mei; Wang, Demin; Hillery, Cheryl A.; Chan, Andrew M.

    2015-01-01

    The trafficking of T-lymphocytes to peripheral draining lymph nodes is crucial for mounting an adaptive immune response. The role of chemokines in the activation of integrins via Ras-related small GTPases has been well established. R-Ras is a member of the Ras-subfamily of small guanosine-5’-triphosphate-binding proteins and its role in T cell trafficking has been investigated in R-Ras null mice (Rras−/−). An examination of the lymphoid organs of Rras−/− mice revealed a 40% reduction in the cellularity of the peripheral lymph nodes. Morphologically, the high endothelial venules of Rras−/− mice were more disorganized and less mature than those of wild-type mice. Furthermore, CD4+ and CD8+ T cells from Rras−/− mice had approximately 42% lower surface expression of L-selectin/CD62L. These aberrant peripheral lymph node phenotypes were associated with proliferative and trafficking defects in Rras−/− T cells. Furthermore, R-Ras could be activated by the chemokine, CCL21. Indeed, Rras−/− T cells had approximately 14.5% attenuation in binding to intercellular adhesion molecule 1 upon CCL21 stimulation. Finally, in a graft-versus host disease model, recipient mice that were transfused with Rras−/− T cells showed a significant reduction in disease severity when compared with mice transplanted with wild-type T cells. These findings implicate a role for R-Ras in T cell trafficking in the high endothelial venules during an effective immune response. PMID:26710069

  3. Leukocytosis and resistance to septic shock in intercellular adhesion molecule 1-deficient mice

    PubMed Central

    1994-01-01

    Intercellular adhesion molecule 1 (ICAM-1) is one of three immunoglobulin superfamily members that bind to the integrins lymphocyte function associated 1 (LFA-1) and Mac-1 on leukocytes. We have generated mice that are genetically and functionally deficient in ICAM-1. These mice have elevated numbers of circulating neutrophils and lymphocytes, as well as diminished allogeneic T cell responses and delayed type hypersensitivity. Mutant mice are resistant to lethal effects of high doses of endotoxin (lipopolysaccharide [LPS]), and this correlates with a significant decrease in neutrophil infiltration in the liver. Production of inflammatory cytokines such as tumor necrosis factor alpha or interleukin 1 is normal in ICAM-1-deficient mice, and thus protection appears to be related to a diminution in critical leukocyte-endothelial interactions. After sensitization with D- galactosamine (D-Gal), ICAM-1-deficient mice are resistant to the lethal effect of low doses of exotoxin (Staphylococcus aureus enterotoxin B [SEB]), which has been shown to mediate its toxic effects via the activation of specific T cells. In this model, ICAM-1-mediated protection against SEB lethality correlates with a decrease in the systemic release of inflammatory cytokines, as well as with prevention of extensive hepatocyte necrosis and hemorrhage. ICAM-1-deficient mice sensitized with D-Gal, however, are not protected from lethality when challenged with low doses of endotoxin (LPS). These studies show that the different contribution of ICAM-1 in the activation of either T cells or macrophages is decisive for the fatal outcome of the shock in these two models. This work suggests that anti-ICAM-1 therapy may be beneficial in both gram-positive and -negative septic shock, either by reducing T cell activation or by diminishing neutrophil infiltration. PMID:7911822

  4. Localization of intercellular adhesion molecule-1 (ICAM-1) in the lungs of silica-exposed mice.

    PubMed Central

    Nario, R C; Hubbard, A K

    1997-01-01

    Intercellular adhesion molecule-1 (ICAM-1) is expressed on a variety of cells including endothelial cells, alveolar epithelial cells, and alveolar macrophages. Endothelial/epithelial cell ICAM-1 participates in the migration of leukocytes out of the blood in response to pulmonary inflammation, whereas alveolar macrophage ICAM-1 may represent cell activation. Our previous studies have shown that there is increased expression of ICAM-1 in lung tissue during acute inflammation following intratracheal injection with silica particles (2 mg/mouse). This increased expression was shown to play a role, in part, in the migration of neutrophils from the circulation into the tissue parenchyma. The aim of the current work is to localize expression of ICAM-1 during acute inflammation in lungs of mice exposed to either silica or the nuisance dust, titanium dioxide. In silica-exposed mice, a significant increase in ICAM-1 was detected on day-1 and localized by immunohistochemistry to aggregates of pulmonary macrophages and to type II epithelial cells. Areas of the lung with increased ICAM-1 expression also showed increased tumor necrosis factor alpha expression. Immunocytochemical staining of bronchoalveolar lavage (BAL) cells demonstrated increased ICAM-1 expression associated with alveolar macrophages 3, 5, and 7 days following silica exposure. Finally, soluble ICAM-1 levels in the BAL fluid were significantly increased in mice exposed to silica on the same days. Titanium dioxide exposure elicited a minimal increase in expression of ICAM-1 in the lungs. These data demonstrate that exposure to the toxic particle silica specifically increases ICAM-1 expression localized to pulmonary macrophages and type II epithelial cells. Images Figure 2. B Figure 2. A Figure 2. D Figure 2. C Figure 3. A Figure 3. B Figure 5. B Figure 5. A Figure 5. C PMID:9400721

  5. Intercellular adhesion molecule-1 expression by skeletal muscle cells augments myogenesis

    SciTech Connect

    Goh, Qingnian; Dearth, Christopher L.; Corbett, Jacob T.; Pierre, Philippe; Chadee, Deborah N.; Pizza, Francis X.

    2015-02-15

    We previously demonstrated that the expression of intercellular adhesion molecule-1 (ICAM-1) by skeletal muscle cells after muscle overload contributes to ensuing regenerative and hypertrophic processes in skeletal muscle. The objective of the present study is to reveal mechanisms through which skeletal muscle cell expression of ICAM-1 augments regenerative and hypertrophic processes of myogenesis. This was accomplished by genetically engineering C2C12 myoblasts to stably express ICAM-1, and by inhibiting the adhesive and signaling functions of ICAM-1 through the use of a neutralizing antibody or cell penetrating peptide, respectively. Expression of ICAM-1 by cultured skeletal muscle cells augmented myoblast–myoblast adhesion, myotube formation, myonuclear number, myotube alignment, myotube–myotube fusion, and myotube size without influencing the ability of myoblasts to proliferate or differentiate. ICAM-1 augmented myotube formation, myonuclear accretion, and myotube alignment through a mechanism involving adhesion-induced activation of ICAM-1 signaling, as these dependent measures were reduced via antibody and peptide inhibition of ICAM-1. The adhesive and signaling functions of ICAM-1 also facilitated myotube hypertrophy through a mechanism involving myotube–myotube fusion, protein synthesis, and Akt/p70s6k signaling. Our findings demonstrate that ICAM-1 expression by skeletal muscle cells augments myogenesis, and establish a novel mechanism through which the inflammatory response facilitates growth processes in skeletal muscle. - Highlights: • We examined mechanisms through which skeletal muscle cell expression of ICAM-1 facilitates events of in vitro myogenesis. • Expression of ICAM-1 by cultured myoblasts did not influence their ability to proliferate or differentiate. • Skeletal muscle cell expression of ICAM-1 augmented myoblast fusion, myotube alignment, myotube–myotube fusion, and myotube size. • ICAM-1 augmented myogenic processes through

  6. Environmental exposure to arsenic and chromium in children is associated with kidney injury molecule-1.

    PubMed

    Cárdenas-González, M; Osorio-Yáñez, C; Gaspar-Ramírez, O; Pavković, M; Ochoa-Martínez, A; López-Ventura, D; Medeiros, M; Barbier, O C; Pérez-Maldonado, I N; Sabbisetti, V S; Bonventre, J V; Vaidya, V S

    2016-10-01

    Environmental hazards from natural or anthropological sources are widespread, especially in the north-central region of Mexico. Children represent a susceptible population due to their unique routes of exposure and special vulnerabilities. In this study we evaluated the association of exposure to environmental kidney toxicants with kidney injury biomarkers in children living in San Luis Potosi (SLP), Mexico. A cross-sectional study was conducted with 83 children (5-12 years of age) residents of Villa de Reyes, SLP. Exposure to arsenic, cadmium, chromium, fluoride and lead was assessed in urine, blood and drinking water samples. Almost all tap and well water samples had levels of arsenic (81.5%) and fluoride (100%) above the permissible levels recommended by the World Health Organization. Mean urine arsenic (45.6ppb) and chromium (61.7ppb) were higher than the biological exposure index, a reference value in occupational settings. Using multivariate adjusted models, we found a dose-dependent association between kidney injury molecule-1 (KIM-1) across chromium exposure tertiles [(T1: reference, T2: 467pg/mL; T3: 615pg/mL) (p-trend=0.001)]. Chromium upper tertile was also associated with higher urinary miR-200c (500 copies/μl) and miR-423 (189 copies/μL). Arsenic upper tertile was also associated with higher urinary KIM-1 (372pg/mL). Other kidney injury/functional biomarkers such as serum creatinine, glomerular filtration rate, albuminuria, neutrophil gelatinase-associated lipocalin and miR-21 did not show any association with arsenic, chromium or any of the other toxicants evaluated. We conclude that KIM-1 might serve as a sensitive biomarker to screen children for kidney damage induced by environmental toxic agents.

  7. Intraocular soluble intracellular adhesion molecule-1 correlates with subretinal fluid height of diabetic macular edema

    PubMed Central

    Zhu, Dan; Zhu, He; Wang, Chunyan; Yang, Dayong

    2014-01-01

    Objective: To investigate the correlations between aqueous concentrations of vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1), soluble intracellular adhesion molecule-1 (sICAM-1) and diabetic macular edema (DME). Materials and Methods: VEGF, MCP-1 and sICAM-1 concentrations in aqueous humor samples of 22 patients with DME and 23 patients with cataract of a control group were measured with solid-phase chemiluminescence immunoassay. Results: Aqueous VEGF (89.2 ± 58.5 pg/ml versus 48.5 ± 27.8 pg/ml, P = 0.006), MCP-1 (684.2 ± 423.4 pg/ml versus 432.4 ± 230.4 pg/ml, P = 0.019) and sICAM-1 (3213.8 ± 2581.6 pg/ml versus 260.2 ± 212.2 pg/ml, P < 0.001) all vary significantly between DME group and control group. Maximum height of submacular fluid measured by Optical coherence tomography (OCT) was significantly associated with aqueous sICAM-1 (r = -0.45, P = 0.034). The maximum height of macular thickness measured by OCT was not significantly associated with either VEGF (P = 0.300), MCP-1 (P = 0.320) or sICAM-1 (P = 0.285). Conclusions: Our results suggest that sICAM-1 may majorly contribute to the formation of subretinal fluid in DME patients and imply that MCP-1 and sICAM-1 may be the potential therapy targets, besides VEGF. PMID:23619489

  8. Synthesis and crystal structure of copper complex of 7,16-bis(2-hydroxy-5-methyl-3-nitrobenzyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane

    NASA Astrophysics Data System (ADS)

    Ma, Shu-lan; Zhu, Wen-xiang

    2002-12-01

    A lariat crown ether compound 7,16-bis(2-hydroxy-5-methylbenzyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane has been prepared via one-pot Mannich reaction. A copper(II) complex with the ligand 7,16-bis(2-hydroxy-5-methyl-3-nitrobenzyl)-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane was unexpectedly synthesized and characterized by elemental analysis, IR and UV spectra. The crystal structure of the complex has been determined by X-ray diffraction. Both crystal structure analysis and spectroscopy study indicated that the side-arm phenols of lariat crown ether are nitrated while complexing with Cu(NO 3) 2. Structure shows that the copper(II) ion is coordinated to two nitrogen and four oxygen atoms, two from the crown ether and other two from the deprotonated phenolate groups. The coordination polyhedron is a distorted octahedron.

  9. Differential effects of heme oxygenase isoforms on heme mediation of endothelial intracellular adhesion molecule 1 expression.

    PubMed

    Wagener, F A; da Silva, J L; Farley, T; de Witte, T; Kappas, A; Abraham, N G

    1999-10-01

    Heme oxygenase (HO), by catabolizing heme to bile pigments, down-regulates cellular hemoprotein, hemoglobin, and heme; the latter generates pro-oxidant products, including free radicals. Two HO isozymes, the products of distinct genes, have been described; HO-1 is the inducible isoform, whereas HO-2 is suggested to be constitutively expressed. We studied the inducing effect of several metal compounds (CoCl(2), stannic mesoporphyrin, and heme) on HO activity. Additionally, we studied HO-1 expression in experimental models of adhesion molecule expression produced by heme in endothelial cells, and the relationship of HO-1 expression to the induced adhesion molecules. Flow cytometry analysis showed that heme induces intracellular adhesion molecule 1 (ICAM-1) expression in a concentration (10-100 microM)- and time (1-24 h)-dependent fashion in human umbilical vein endothelial cells. Pretreatment with stannic mesoporphyrin, an inhibitor of HO activity, caused a 2-fold increase in heme-induced ICAM-1 expression. In contrast, HO induction by CoCl(2) decreased heme-induced ICAM-1 expression by 33%. To examine the contribution of HO-1 and HO-2 to endothelial HO activity, specific antisense oligonucleotides (ODNs) of each isoform were tested for their specificity to inhibit HO activity in cells exposed to heme. Endothelial cells exposed to heme elicited increased HO activity, which was prevented (70%) by HO-1 antisense ODNs. HO-2 antisense ODN inhibited heme-induced HO activity by 21%. Addition of HO-1 antisense ODNs prevented heme degradation and resulted in elevation of microsomal heme. Western blot analysis showed that HO-1 antisense ODNs selectively inhibited HO-1 protein and failed to inhibit HO-2 protein. Incubation of endothelial cells with HO-1 antisense enhanced heme-dependent increase of ICAM-1. In contrast, addition of HO-2 antisense to endothelial cells failed to increase adhesion molecules. The role of glutathione, an important antioxidant, was examined on heme

  10. Role of intercellular adhesion molecule-1 in glucan-induced pulmonary granulomatosis in the rat.

    PubMed

    Barton, P A; Imlay, M M; Flory, C M; Warren, J S

    1996-08-01

    Glucan-induced pulmonary granulomatous vasculitis in the rat mimics several human lung diseases (e.g., Wegener's granulomatosis, intravenous talcosis). We sought to clarify the role of intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of glucan-induced granulomatous vasculitis. Immunohistochemical analysis of lung sections from rats with florid vasculitis (48 hours) revealed marked alveolar septal and lesional expression of ICAM-1. An ex vivo binding analysis with isotope-labeled antibodies and lung sections taken at various times up to 48 hours after glucan infusion revealed a progressive increase in whole-lung ICAM-1 expression. In vivo measurements of vascular wall-associated ICAM-1 expression revealed an earlier rise that began less than 6 hours after glucan infusion, peaked at 24 to 48 hours, and then declined to near baseline during the ensuing 24 to 96 hours. To assess whether ICAM-1 expression both within blood vessel walls and within lesions per se is important in granuloma development, we carried out in vivo neutralization experiments with several different routes of administration of antibody to ICAM-1. Monoclonal antibody to rat ICAM-1 was either infused intravenously at time 0 (when glucan was infused), infused intravenously at time 0 and after 24 hours, instilled only intratracheally 24 hours after glucan infusion, or given both intravenously (time = 0 and 24 hours) and intratracheally (time = 24 hours). Infusions of monoclonal antibody to rat ICAM-1 resulted in dose-dependent reductions in mean granuloma number and cross-sectional area. Intrapulmonary instillation of antibody to rat ICAM-1 (via tracheostomy 24 hours after glucan infusion) resulted in a modest reduction in mean granuloma number and cross-sectional area. When antibody to ICAM-1 was both infused and instilled via the trachea, we found an additive reduction in mean granuloma size and number. There was a 12-fold increase in adhesion of ED-1-positive peripheral blood

  11. Studying the properties and response of a large volume (946 cm3) LaBr3:Ce detector with γ-rays up to 22.5 MeV

    NASA Astrophysics Data System (ADS)

    Mazumdar, I.; Gothe, D. A.; Anil Kumar, G.; Yadav, N.; Chavan, P. B.; Patel, S. M.

    2013-03-01

    This paper presents the results of our measurements and detailed simulations using GEANT4 to investigate the performance of a large volume (946 cm3) cylindrical (3.5 in.diameter×6 in.length) LaBr3:Ce detector. The properties of the detector have been studied using γ-rays from radioactive sources and in-beam reaction, from few hundred keV to 22.5 MeV. The salient features, which have been studied in-depth, are the uniformity and internal activity of the crystal, the energy and timing resolutions, linearity of the response up to 22.5 MeV, and efficiencies. A highly linear response has been observed by extracting the energy signal from a lower dynode and operating the PMT at a low voltage. The detector is to be primarily used for measuring high energy γ-rays spectra from Giant Dipole Resonance (GDR) decay studies.

  12. 1015 cm-3 eV-1 level detection of density of states of a p-type polymer by hν-dependent high-sensitivity ultraviolet photoemission spectroscopy

    NASA Astrophysics Data System (ADS)

    Sato, Tomoya; Kinjo, Hiroumi; Yamazaki, Junki; Ishii, Hisao

    2017-01-01

    We propose a method, called hν-dependent high-sensitivity ultraviolet photoemission spectroscopy, to observe the density of states (DOS) in a very wide range from HOMO to extremely weak gap states (1022 to 1015 cm-3 eV-1 in density of states). The method was applied to a p-type semiconducting polymer. A series of spectra for hν = 4.4-7.7 eV were recorded, and the DOS was obtained by overlapping the spectral part with a similar line shape between adjacent photon energy spectra to eliminate the photon energy dependence of the photoionization cross section. This method can be applied to both organic and inorganic materials, providing useful information about the DOS of functional materials.

  13. Highlights from the 13th European Congress of Clinical Microbiology and Infectious Diseases in Glasgow, Scotland, May 10-13, 2003. The complex world of infectious diseases.

    PubMed

    Jack, David

    2003-01-01

    At the 13th European Congress of Clinical Microbiology and Infectious Diseases, held in Glasgow, Scotland, May 10-13, 2003, the latest developments in clinical microbiology and the treatment of infectious diseases were presented alongside recent progress on molecular aspects of diagnosis and emerging patterns of infection. Around 5,000 delegates from more than 80 countries attended the congress, which saw the presentation of more than 400 oral communications and 1,700 posters. In addition to a historical session looking at Scotland's own contribution to the control of infectious diseases, the meeting involved up to six parallel sessions a day, looking at all the major aspects of infectious diseases, treatment, surveillance, epidemiology and drug pharmacodynamics and pharmacokinetics. The organizers also organized a Late Breaker symposium on severe acute respiratory syndrome. The topics likely to be of most interest to Drug News and Perspectives readers are described here.

  14. Laboratory-Scale Column Testing Using IONSIV IE-911 for Removing Cesium from Acidic Tank Waste Simulant. 1: Cesium Exchange Capacity of a 15-cm3 Column and Dynamic Stability of the Exchange Media

    SciTech Connect

    T.J. Tranter; R.D. Tillotson; T.A. Todd

    2005-04-01

    Bench-scale column tests were performed using a commercial form of crystalline silicotitanate (CST) for removing radio-cesium from a surrogate acidic tank solution representative of liquid waste stored at the Idaho National Engineering and Environmental Laboratory (INEEL). An engineered form of CST ion exchanger, known as IONSIVtm IE-911 (UOP, Mt Laurel, NJ, USA), was tested in 15 cm3 columns at a flow rate of 5 bed volumes per hour. These experiments showed the ion exchange material to have reasonable selectivity and capacity for removing cesium from the complex chemical matrix of the solution. However, previous testing indicated that partial neutralization of the feed stream was necessary to increase the stability of the ion exchange media. Thus, in these studies, CST degradation was determined as a function of throughput in order to better assess the stability characteristics of the exchanger for potential future waste treatment applications. Results of these tests indicate that the degradation of the CST reaches a maximum very soon after the acidic feed is introduced to the column and then rapidly declines. Total dissolution of bed material did not exceed 3% under the experimental regime used.

  15. MITF is a critical regulator of the carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) in malignant melanoma.

    PubMed

    Ullrich, Nico; Löffek, Stefanie; Horn, Susanne; Ennen, Marie; Sánchez-Del-Campo, Luis; Zhao, Fang; Breitenbuecher, Frank; Davidson, Irwin; Singer, Bernhard B; Schadendorf, Dirk; Goding, Colin R; Helfrich, Iris

    2015-11-01

    The multifunctional Ig-like carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is neo-expressed in the majority of malignant melanoma lesions. CEACAM1 acts as a driver of tumor cell invasion, and its expression correlates with poor patient prognosis. Despite its importance in melanoma progression, how CEACAM1 expression is regulated is largely unknown. Here, we show that CEACAM1 expression in melanoma cell lines and melanoma tissue strongly correlates with that of the microphthalmia-associated transcription factor (MITF), a key regulator of melanoma proliferation and invasiveness. MITF is revealed as a direct and positive regulator for CEACAM1 expression via binding to an M-box motif located in the CEACAM1 promoter. Taken together, our study provides novel insights into the regulation of CEACAM1 expression and suggests an MITF-CEACAM1 axis as a potential determinant of melanoma progression.

  16. Role of intercellular adhesion molecule 1 in pathogenesis of staphylococcal arthritis and in host defense against staphylococcal bacteremia.

    PubMed Central

    Verdrengh, M; Springer, T A; Gutierrez-Ramos, J C; Tarkowski, A

    1996-01-01

    Intercellular adhesion molecule 1 (ICAM-1) is a member of the immunoglobulin superfamily that interacts with two integrins, LFA-1 and Mac-1. These interactions are critical for leukocyte extravasation into inflamed tissue. To assess the role of ICAM-1 expression in the pathogenesis of bacterial infection, homozygously mutant mice lacking the ICAM-1 gene were exposed to Staphylococcus aureus. Within 6 days after inoculation 50% of the animals in the ICAM-1(-/-) group, but none of the controls, had died. Despite the high level of mortality, ICAM-1(-/-) mice developed less frequent and less severe arthritis than their wild-type littermates. In agreement, normal mice inoculated with staphylococci and administered anti-ICAM-1 antibodies exhibited a higher frequency of mortality but less severe arthritis than the controls. Our results indicate that ICAM-1 on the one hand provides protection against systemic disease but on the other hand aggravates the local disease manifestation. PMID:8698512

  17. Cutting edge: DNAX accessory molecule 1-deficient CD8+ T cells display immunological synapse defects that impair antitumor immunity.

    PubMed

    Ramsbottom, Kelly M; Hawkins, Edwin D; Shimoni, Raz; McGrath, Mairi; Chan, Christopher J; Russell, Sarah M; Smyth, Mark J; Oliaro, Jane

    2014-01-15

    DNAX accessory molecule 1 (DNAM-1) is expressed on all CD8(+) T cells and promotes their activation and effector function. DNAM-1 interacts with LFA-1, a critical molecule for immunological synapse formation between T cells and APCs, and for cytotoxic killing of target cells. Mice that lack DNAM-1 display abnormal T cell responses and antitumor activity; however, the mechanism involved is unclear. In this article, we show that DNAM-1 deficiency results in reduced proliferation of CD8(+) T cells after Ag presentation and impaired cytotoxic activity. We also demonstrate that DNAM-1-deficient T cells show reduced conjugations with tumor cells and decreased recruitment of both LFA-1 and lipid rafts to the immunological synapse, which correlates with reduced tumor cell killing in vitro. This synapse defect may explain why DNAM-1-deficient mice cannot clear tumors in vivo, and highlights the importance of DNAM-1 and the immunological synapse in T cell-mediated antitumor immunity.

  18. Human Dermal Mast Cells Contain and Release Tumor Necrosis Factor α, which Induces Endothelial Leukocyte Adhesion Molecule 1

    NASA Astrophysics Data System (ADS)

    Walsh, Laurence J.; Trinchieri, Giorgio; Waldorf, Heidi A.; Whitaker, Diana; Murphy, George F.

    1991-05-01

    Tumor necrosis factor α (TNF-α) is a proinflammatory cytokine that mediates endothelial leukocyte interactions by inducing expression of adhesion molecules. In this report, we demonstrate that human dermal mast cells contain sizeable stores of immunoreactive and biologically active TNF-α within granules, which can be released rapidly into the extracellular space upon degranulation. Among normal human dermal cells, mast cells are the predominant cell type that expresses both TNF-α protein and TNF-α mRNA. Moreover, induction of endothelial leukocyte adhesion molecule 1 expression is a direct consequence of release of mast cell-derived TNF-α. These findings establish a role for human mast cells as "gatekeepers" of the dermal microvasculature and indicate that mast cell products other than vasoactive amines influence endothelium in a proinflammatory fashion.

  19. Electrical detection of kidney injury molecule-1 with AlGaN/GaN high electron mobility transistors

    SciTech Connect

    Wang, H. T.; Kang, B. S.; Ren, F.; Pearton, S. J.; Johnson, J. W.; Rajagopal, P.; Roberts, J. C.; Piner, E. L.; Linthicum, K. J.

    2007-11-26

    AlGaN/GaN high electron mobility transistors (HEMTs) were used to detect kidney injury molecule-1 (KIM-1), an important biomarker for early kidney injury detection. The gate region consisted of 5 nm gold deposited onto the AlGaN surface. The gold was conjugated to highly specific KIM-1 antibodies through a self-assembled monolayer of thioglycolic acid. The HEMT source-drain current showed a clear dependence on the KIM-1 concentration in phosphate-buffered saline solution. The limit of detection was 1 ng/ml using a 20x50 {mu}m{sup 2} gate sensing area. This approach shows potential for both preclinical and clinical kidney injury diagnosis with accurate, rapid, noninvasive, and high throughput capabilities.

  20. Electrical detection of kidney injury molecule-1 with AlGaN /GaN high electron mobility transistors

    NASA Astrophysics Data System (ADS)

    Wang, H. T.; Kang, B. S.; Ren, F.; Pearton, S. J.; Johnson, J. W.; Rajagopal, P.; Roberts, J. C.; Piner, E. L.; Linthicum, K. J.

    2007-11-01

    AlGaN /GaN high electron mobility transistors (HEMTs) were used to detect kidney injury molecule-1 (KIM-1), an important biomarker for early kidney injury detection. The gate region consisted of 5nm gold deposited onto the AlGaN surface. The gold was conjugated to highly specific KIM-1 antibodies through a self-assembled monolayer of thioglycolic acid. The HEMT source-drain current showed a clear dependence on the KIM-1 concentration in phosphate-buffered saline solution. The limit of detection was 1ng/ml using a 20×50μm2 gate sensing area. This approach shows potential for both preclinical and clinical kidney injury diagnosis with accurate, rapid, noninvasive, and high throughput capabilities.

  1. A physics package for rubidium atomic frequency standard with a short-term stability of 2.4 × 10-13 τ-1/2

    NASA Astrophysics Data System (ADS)

    Hao, Qiang; Li, Wenbing; He, Shengguo; Lv, Jianfeng; Wang, Pengfei; Mei, Ganghua

    2016-12-01

    In this article, a new type of physics package with high signal to noise ratio for a rubidium atomic frequency standard is reported. To enhance the clock transition signal, a slotted tube microwave cavity with a field orientation factor of 0.93 and an absorption cell with the diameter of 30 mm were utilized in design of the cavity-cell assembly. Based on the spectral analysis of the three commonly used rubidium spectral lamps, the spectral lamp filled with Xe gas was chosen as the optical pumping source for its small line shape distortion. To suppress the shot noise of the signal, a band pass interference filter was used to filter out Xe spectral lines from the pumping light. A desk system of the rubidium frequency standard with the physics package was realized, and the short-term stability of the system was predicted and tested. The measured result is 2.4 × 10-13 τ-1/2 up to 100 s averaging time, in good agreement with the predicted one.

  2. A physics package for rubidium atomic frequency standard with a short-term stability of 2.4 × 10(-13) τ(-1/2).

    PubMed

    Hao, Qiang; Li, Wenbing; He, Shengguo; Lv, Jianfeng; Wang, Pengfei; Mei, Ganghua

    2016-12-01

    In this article, a new type of physics package with high signal to noise ratio for a rubidium atomic frequency standard is reported. To enhance the clock transition signal, a slotted tube microwave cavity with a field orientation factor of 0.93 and an absorption cell with the diameter of 30 mm were utilized in design of the cavity-cell assembly. Based on the spectral analysis of the three commonly used rubidium spectral lamps, the spectral lamp filled with Xe gas was chosen as the optical pumping source for its small line shape distortion. To suppress the shot noise of the signal, a band pass interference filter was used to filter out Xe spectral lines from the pumping light. A desk system of the rubidium frequency standard with the physics package was realized, and the short-term stability of the system was predicted and tested. The measured result is 2.4 × 10(-13) τ(-1/2) up to 100 s averaging time, in good agreement with the predicted one.

  3. Electronic, infrared and Raman spectral studies on the molecular complex of N, N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane with iodine

    NASA Astrophysics Data System (ADS)

    El-Nemma, Eman M.

    2004-11-01

    The molecular complexation reaction between iodine and the interesting mixed oxygen-nitrogen cyclic base N, N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane (DBTODAOD) has been studied spectrophotometrically in CH 2Cl 2, CHCl 3, and CCl 4. The results of photometric titrations and elemental analysis show that the DBTODAOD base:iodine ratio is 1:4 forming the heptaiodide complex [(DBTODAOD)I] +·I 7-. The heptaiodide ion (I 7-) is described as I 3-(2I 2) confirmed by the observation of its characteristic strong absorptions around 365 and 295 nm. In addition, the far infrared spectrum of the solid complex shows the three vibrations of I 3- unit at 142, 104, and 62 cm -1 assigned to νas(I-I), νs(I-I) and δ(I -3), respectively, while the Raman spectrum shows the corresponding bands at 147 and 108 cm -1 beside two other bands at 181 and 214 cm -1 related to the vibration of the I 2 unit and the first overtone of νs(I-I) of I 3-, respectively. The structure of the formed heptaiodide complex was further supported by thermal gravimetric analysis measurements. Group theoretical analysis indicate that the triiodide unit (I 3-) in I 7- may be non-linear with C 2v symmetry.

  4. Electronic, infrared and Raman spectral studies on the molecular complex of N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane with iodine.

    PubMed

    El-Nemma, Eman M

    2004-11-01

    The molecular complexation reaction between iodine and the interesting mixed oxygen-nitrogen cyclic base N,N'-dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclooctadecane (DBTODAOD) has been studied spectrophotometrically in CH2Cl2, CHCl3, and CCl4. The results of photometric titrations and elemental analysis show that the DBTODAOD base:iodine ratio is 1:4 forming the heptaiodide complex [(DBTODAOD)I]+.I7-. The heptaiodide ion (I7-) is described as I3-(2I2) confirmed by the observation of its characteristic strong absorptions around 365 and 295 nm. In addition, the far infrared spectrum of the solid complex shows the three vibrations of I3- unit at 142, 104, and 62 cm(-1) assigned to nuas(I-I), nus(I-I) and delta(I-3), respectively, while the Raman spectrum shows the corresponding bands at 147 and 108 cm(-1) beside two other bands at 181 and 214 cm(-1) related to the vibration of the I2 unit and the first overtone of nus(I-I) of I3-, respectively. The structure of the formed heptaiodide complex was further supported by thermal gravimetric analysis measurements. Group theoretical analysis indicate that the triiodide unit (I3-) in I7- may be non-linear with C2v symmetry.

  5. In situ synthesis, photometric and spectroscopic studies of chelating system during the 1,4,7,10,13,16-hexaoxacyclooctadecane charge transfer reaction with different acceptors

    NASA Astrophysics Data System (ADS)

    Hossan, Aisha S. M.; Abou-Melha, Hanaa M.; Refat, Moamen S.

    2011-08-01

    Electron donor acceptor complexes (EDA) of the 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6) as a rich donor were spectrophotometrically discussed and synthesized in solid form according the interactions with different nine of usual π-acceptors like 2,3,5,6-tetrachlorocyclohexa-2,5-diene-1,4-dione (p-chloranil; p-CHL), tetrachloro-1,2-benzoquinone (o-chloranil; o-CHL), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), tetracyanoquinodimethane (TCNQ), 2,6-dichloroquinone-4-chloroimide (DCQ), 2,6-dibromoquinone-4-chloroimide (DBQ), 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid; CLA), N-bromosuccinimide (NBS), 2,4,6-trinitrophenol (picric acid; PA). Spectroscopic and physical data such as formation constant ( KCT), molar extinction coefficient ( ɛCT), standard free energy (Δ G°), oscillator strength ( f), transition dipole moment ( μ), resonance energy ( RN) and ionization potential ( Ip) were estimated in chloroform or methanol at 25 °C. Based on the elemental analysis and photometric titrations the CT-complexes were formed indicated the formation of 1:1 charge-transfer complexes for the o-CHL, TCNQ, DCQ, DBQ and NBS acceptors but 1:3 ratio for p-CHL, DDQ, CLA and PA, respectively. The charge-transfer interactions were interpretative according to the formation of dative ion pairs [18C6 rad +, A rad -], where A is acceptor. All of the resulting charge transfer complexes were isolated in amorphous form and the complexes formations on IR and 1H NMR spectra were discussed.

  6. Fabrication of a highly selective cadmium (II) sensor based on 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane as a supramolecular ionophore.

    PubMed

    Ghaemi, Arezoo; Tavakkoli, Haman; Mombeni, Tayebeh

    2014-05-01

    A new cadmium (II) ion selective sensor based on 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (kryptofix5) as a supramolecular carrier has been developed. The membrane solutions containing polyvinyl chloride (PVC), plasticizer, sodium tetraphenylborate (NaTPB) as a lipophilic ionic additive and kryptofix5 as an ionophore were directly coated on the surface of graphite rods. The best composition of the coated membrane (w/w%) was found to be: 30.0% PVC, 61.0% dioctyl sebacate (DOS), 6.0% NaTPB and 3.0% kryptofix5. The sensor indicates a good linear response for Cd(2+) cation over a wide concentration range from 1.0×10(-5) to 1.0×10(-1) M with a Nernstian slope of 29.8±0.1 mV/decade and the detection limit is 8.4×10(-6) M. The response time of the sensor is 15s and it can be used for 7 weeks without significant drift in potential. The sensor operates in the wide pH range of 1.0-6.0. This sensor reveals a very good selectivity toward Cd(2+) ion over a wide range of alkali, transition and heavy metal cations. The sensor was used as an indicator electrode for potentiometric titration of Cd(2+) using sodium fluoride and ethylenediaminetetraacetic acid (EDTA) solutions with a sharp potential change that occurred at the end point. In addition, the proposed sensor was successfully used for determination of Cd(2+) cation in real water samples.

  7. Identification of Human Junctional Adhesion Molecule 1 as a Functional Receptor for the Hom-1 Calicivirus on Human Cells.

    PubMed

    Sosnovtsev, Stanislav V; Sandoval-Jaime, Carlos; Parra, Gabriel I; Tin, Christine M; Jones, Ronald W; Soden, Jo; Barnes, Donna; Freeth, Jim; Smith, Alvin W; Green, Kim Y

    2017-02-14

    The Hom-1 vesivirus was reported in 1998 following the inadvertent transmission of the animal calicivirus San Miguel sea lion virus to a human host in a laboratory. We characterized the Hom-1 strain and investigated the mechanism by which human cells could be infected. An expression library of 3,559 human plasma membrane proteins was screened for reactivity with Hom-1 virus-like particles, and a single interacting protein, human junctional adhesion molecule 1 (hJAM1), was identified. Transient expression of hJAM1 conferred susceptibility to Hom-1 infection on nonpermissive Chinese hamster ovary (CHO) cells. Virus infection was markedly inhibited when CHO cells stably expressing hJAM were pretreated with anti-hJAM1 monoclonal antibodies. Cell lines of human origin were tested for growth of Hom-1, and efficient replication was observed in HepG2, HuH7, and SK-CO15 cells. The three cell lines (of hepatic or intestinal origin) were confirmed to express hJAM1 on their surface, and clustered regularly interspaced short palindromic repeats/Cas9-mediated knockout of the hJAM1 gene in each line abolished Hom-1 propagation. Taken together, our data indicate that entry of the Hom-1 vesivirus into these permissive human cell lines is mediated by the plasma membrane protein hJAM1 as a functional receptor.IMPORTANCE Vesiviruses, such as San Miguel sea lion virus and feline calicivirus, are typically associated with infection in animal hosts. Following the accidental infection of a laboratory worker with San Miguel sea lion virus, a related virus was isolated in cell culture and named Hom-1. In this study, we found that Hom-1 could be propagated in a number of human cell lines, making it the first calicivirus to replicate efficiently in cultured human cells. Screening of a library of human cell surface membrane proteins showed that the virus could utilize human junctional adhesion molecule 1 as a receptor to enter cells and initiate replication. The Hom-1 virus presents a new

  8. Epidermal Expression of Intercellular Adhesion Molecule 1 is Not a Primary Inducer of Cutaneous Inflammation in Transgenic Mice

    NASA Astrophysics Data System (ADS)

    Williams, Ifor R.; Kupper, Thomas S.

    1994-10-01

    Keratinocytes at sites of cutaneous inflammation have increased expression of intercellular adhesion molecule 1 (ICAM-1), a cytokine-inducible adhesion molecule which binds the leukocyte integrins LFA-1 and Mac-1. Transgenic mice were prepared in which the expression of mouse ICAM-1 was targeted to basal keratinocytes by using the human K14 keratin promoter. The level of constitutive expression attained in the transgenic mice exceeded the peak level of ICAM-1 expression induced on nontransgenic mouse keratinocytes in vitro by optimal combinations of interferon γ and tumor necrosis factor α or in vivo by proinflammatory stimuli such as phorbol 12-myristate 13-acetate. In vitro adhesion assays demonstrated that cultured transgenic keratinocytes were superior to normal keratinocytes as a substrate for the LFA-1-dependent binding of mouse T cells, confirming that the transgene-encoded ICAM-1 was expressed in a functional form. However, the high level of constitutive ICAM-1 expression achieved on keratinocytes in vivo in these transgenic mice did not result in additional recruitment of CD45^+ leukocytes into transgenic epidermis, nor did it elicit dermal inflammation. Keratinocyte ICAM-1 expression also did not potentiate contact-hypersensitivity reactions to epicutaneous application of haptens. The absence of a spontaneous phenotype in these transgenic mice was not the result of increased levels of soluble ICAM-1, since serum levels of soluble ICAM-1 were equal in transgenic mice and controls. We conclude that elevated ICAM-1 expression on keratinocytes cannot act independently to influence leukocyte trafficking and elicit cutaneous inflammation.

  9. Early Detection of Junctional Adhesion Molecule-1 (JAM-1) in the Circulation after Experimental and Clinical Polytrauma.

    PubMed

    Denk, Stephanie; Wiegner, Rebecca; Hönes, Felix M; Messerer, David A C; Radermacher, Peter; Weiss, Manfred; Kalbitz, Miriam; Ehrnthaller, Christian; Braumüller, Sonja; McCook, Oscar; Gebhard, Florian; Weckbach, Sebastian; Huber-Lang, Markus

    2015-01-01

    Severe tissue trauma-induced systemic inflammation is often accompanied by evident or occult blood-organ barrier dysfunctions, frequently leading to multiple organ dysfunction. However, it is unknown whether specific barrier molecules are shed into the circulation early after trauma as potential indicators of an initial barrier dysfunction. The release of the barrier molecule junctional adhesion molecule-1 (JAM-1) was investigated in plasma of C57BL/6 mice 2 h after experimental mono- and polytrauma as well as in polytrauma patients (ISS ≥ 18) during a 10-day period. Correlation analyses were performed to indicate a linkage between JAM-1 plasma concentrations and organ failure. JAM-1 was systemically detected after experimental trauma in mice with blunt chest trauma as a driving force. Accordingly, JAM-1 was reduced in lung tissue after pulmonary contusion and JAM-1 plasma levels significantly correlated with increased protein levels in the bronchoalveolar lavage as a sign for alveolocapillary barrier dysfunction. Furthermore, JAM-1 was markedly released into the plasma of polytrauma patients as early as 4 h after the trauma insult and significantly correlated with severity of disease and organ dysfunction (APACHE II and SOFA score). The data support an early injury- and time-dependent appearance of the barrier molecule JAM-1 in the circulation indicative of a commencing trauma-induced barrier dysfunction.

  10. Soluble Vascular Cell Adhesion Molecule-1 (VCAM-1) as a Biomarker in the Mouse Model of Experimental Autoimmune Myocarditis (EAM)

    PubMed Central

    Grabmaier, U.; Kania, G.; Kreiner, J.; Grabmeier, J.; Uhl, A.; Huber, B. C.; Lackermair, K.; Herbach, N.; Todica, A.; Eriksson, U.; Weckbach, L. T.; Brunner, S.

    2016-01-01

    Vascular cell adhesion molecule-1 (VCAM-1) is strongly upregulated in hearts of mice with coxsackie virus-induced as well as in patients with viral infection-triggered dilated cardiomyopathy. Nevertheless, the role of its soluble form as a biomarker in inflammatory heart diseases remains unclear. Therefore, we investigated whether plasma levels of soluble VCAM-1 (sVCAM-1) directly correlated with disease activity and progression of cardiac dysfunction in the mouse model of experimental autoimmune myocarditis (EAM). EAM was induced by immunization of BALB/c mice with heart-specific myosin-alpha heavy chain peptide together with complete Freund`s adjuvant. ELISA revealed strong expression of cardiac VCAM-1 (cVCAM-1) throughout the course of EAM in immunized mice compared to control animals. Furthermore, sVCAM-1 was elevated in the plasma of immunized compared to control mice at acute and chronic stages of the disease. sVCAM-1 did not correlate with the degree of acute cardiac inflammation analyzed by histology or cardiac cytokine expression investigated by ELISA. Nevertheless, heart to body weight ratio correlated significantly with sVCAM-1 at chronic stages of EAM. Cardiac systolic dysfunction studied with positron emission tomography indicated a weak relationship with sVCAM-1 at the chronic stage of the disease. Our data provide evidence that plasma levels of sVCAM-1 are elevated throughout all stages of the disease but showed no strong correlation with the severity of EAM. PMID:27501319

  11. Mechanism of Collaborative Enhancement of Binding of Paired Antibodies to Distinct Epitopes of Platelet Endothelial Cell Adhesion Molecule-1

    PubMed Central

    Greineder, Colin F.; Villa, Carlos H.; Hood, Elizabeth D.; Shuvaev, Vladimir V.; Sun, Jing; Chacko, Ann-Marie; Abraham, Valsamma; DeLisser, Horace M.; Muzykantov, Vladimir R.

    2017-01-01

    Monoclonal antibodies (mAbs) directed to extracellular epitopes of human and mouse Platelet Endothelial Cell Adhesion Molecule-1 (CD31 or PECAM-1) stimulate binding of other mAbs to distinct adjacent PECAM-1 epitopes. This effect, dubbed Collaborative Enhancement of Paired Affinity Ligands, or CEPAL, has been shown to enhance delivery of mAb-targeted drugs and nanoparticles to the vascular endothelium. Here we report new insights into the mechanism underlying this effect, which demonstrates equivalent amplitude in the following models: i) cells expressing a full length PECAM-1 and mutant form of PECAM-1 unable to form homodimers; ii) isolated fractions of cellular membranes; and, iii) immobilized recombinant PECAM-1. These results indicate that CEPAL is mediated not by interference in cellular functions or homophilic PECAM-1 interactions, but rather by conformational changes within the cell adhesion molecule induced by ligand binding. This mechanism, mediated by exposure of partially occult epitopes, is likely to occur in molecules other than PECAM-1 and may represent a generalizable phenomenon with valuable practical applications. PMID:28085903

  12. Expression of intercellular adhesion molecule 1 (ICAM-1) on the human oviductal epithelium and mediation of lymphoid cell adherence.

    PubMed

    Utreras, E; Ossandon, P; Acuña-Castillo, C; Varela-Nallar, L; Müller, C; Arraztoa, J A; Cardenas, H; Imarai, M

    2000-09-01

    The epithelium of the human oviduct expresses the major histocompatibility complex (MHC) class II and shows endocytic properties towards luminal antigens. Therefore, the epithelial cells might behave as antigen-presenting cells, inducing a local immune response. The activation of antigen-specific T cells not only requires presentation of the peptide antigen by MHC class II, but also the presence of co-stimulatory molecules in the antigen-presenting cells. Therefore, the expression of the intercellular adhesion molecule 1 (ICAM-1) was examined in the epithelium of the human oviduct. Most oviducts showed epithelial ICAM-1 expression, as assessed by immunocytochemistry, western blot analysis and RT-PCR assay, and the expression was restricted to the luminal border of ciliated and secretory cells. Interferon gamma, interleukin 1 and lipopolysaccharide treatments increased the percentage of ICAM-1-positive cells in primary cultures, indicating that the expression of ICAM-1 in the oviduct might be upregulated in vivo by inflammatory cytokines or bacterial infections. Binding assays between allogenic phytohaemagglutinin-activated lymphocytes and epithelial monolayers expressing ICAM-1 demonstrated that this molecule stimulated lymphocyte adherence. The presence of ICAM-1, in addition to MHC class II, supports the putative role of the oviductal epithelium in antigen presentation. The exclusive apical distribution of ICAM-1 indicates that T-cell activation would occur in a polarized manner. Binding of lymphoid cells to the surface of the oviductal epithelium may help to retain these immune cells that are required for the clearance of pathogens.

  13. Novel Wnt Regulator NEL-Like Molecule-1 Antagonizes Adipogenesis and Augments Osteogenesis Induced by Bone Morphogenetic Protein 2

    PubMed Central

    Shen, Jia; James, Aaron W.; Zhang, Xinli; Pang, Shen; Zara, Janette N.; Asatrian, Greg; Chiang, Michael; Lee, Min; Khadarian, Kevork; Nguyen, Alan; Lee, Kevin S.; Siu, Ronald K.; Tetradis, Sotirios; Ting, Kang; Soo, Chia

    2017-01-01

    The differentiation factor NEL-like molecule-1 (NELL-1) has been reported as osteoinductive in multiple in vivo preclinical models. Bone morphogenetic protein (BMP)-2 is used clinically for skeletal repair, but in vivo administration can induce abnormal, adipose-filled, poor-quality bone. We demonstrate that NELL-1 combined with BMP2 significantly optimizes osteogenesis in a rodent femoral segmental defect model by minimizing the formation of BMP2-induced adipose-filled cystlike bone. In vitro studies using the mouse bone marrow stromal cell line M2-10B4 and human primary bone marrow stromal cells have confirmed that NELL-1 enhances BMP2-induced osteogenesis and inhibits BMP2-induced adipogenesis. Importantly, the ability of NELL-1 to direct BMP2-treated cells toward osteogenesis and away from adipogenesis requires intact canonical Wnt signaling. Overall, these studies establish the feasibility of combining NELL-1 with BMP2 to improve clinical bone regeneration and provide mechanistic insight into canonical Wnt pathway activity during NELL-1 and BMP2 osteogenesis. The novel abilities of NELL-1 to stimulate Wnt signaling and to repress adipogenesis may highlight new treatment approaches for bone loss in osteoporosis. PMID:26772960

  14. Active Site Formation, Not Bond Kinetics, Limits Adhesion Rate between Human Neutrophils and Immobilized Vascular Cell Adhesion Molecule 1

    PubMed Central

    Waugh, Richard E.; Lomakina, Elena B.

    2009-01-01

    Abstract The formation of receptor ligand bonds at the interface between different cells and between cells and substrates is a widespread phenomenon in biological systems. Physical measurements of bond formation rates between cells and substrates have been exploited to increase our understanding of the biophysical mechanisms that regulate bond formation at interfaces. Heretofore, these measurements have been interpreted in terms of simple bimolecular reaction kinetics. Discrepancies between this simple framework and the behavior of neutrophils adhering to surfaces expressing vascular cell adhesion molecule 1 (VCAM-1) motivated the development of a new kinetic framework in which the explicit formation of active bond formation sites (reaction zones) are a prerequisite for bond formation to occur. Measurements of cells interacting with surfaces having a wide range of VCAM-1 concentrations, and for different durations of contact, enabled the determination of novel kinetic rate constants for the formation of reaction zones and for the intrinsic bond kinetics. Comparison of these rates with rates determined previously for other receptor-ligand pairs points to a predominant role of extrinsic factors such as surface topography and accessibility of active molecules to regions of close contact in determining forward rates of bond formation at cell interfaces. PMID:19134479

  15. Intercellular adhesion molecule-1 expression in experimental alcoholic liver disease: relationship to endotoxemia and TNF alpha messenger RNA.

    PubMed

    Nanji, A A; Griniuviene, B; Yacoub, L K; Fogt, F; Tahan, S R

    1995-02-01

    We used the intragastric feeding rat model for alcoholic liver disease to evaluate the relationship among intercellular adhesion molecule-1 (ICAM-1) expression, tumor necrosis factor-alpha (TNF-alpha), plasma endotoxin, and inflammatory changes in the liver. Rats were fed different dietary fats (saturated fat, corn oil, and fish oil) with ethanol; control rats were fed isocaloric amounts of dextrose instead of ethanol. At sacrifice the following were evaluated: liver pathologic changes, TNF-alpha mRNA by reverse transcription-PCR, plasma endotoxin, and ICAM-1 by immunohistochemistry and immunoblot analysis. Upregulation of ICAM-1 in endothelial lining cells in central and portal veins was observed in rats showing evidence of pathologic changes. Rats fed fish oil and ethanol, which exhibited the most severe inflammation, also showed hepatocyte ICAM-1 staining. The presence of ICAM-1 staining, in general, correlated with the level of TNF-alpha mRNA expression and plasma endotoxin levels. Upregulation of ICAM-1 in rats fed ethanol may contribute to the inflammatory changes seen in this model. The association between ICAM-1 upregulation and endotoxin and TNF-alpha mRNA suggests a role for these mediators in the inflammatory process in alcoholic liver injury.

  16. Soluble interleukin-2 receptor, intercellular adhesion molecule-1 and interleukin-10 serum levels in patients with melanoma.

    PubMed

    Boyano, M D; Garcia-Vázquez, M D; López-Michelena, T; Gardeazabal, J; Bilbao, J; Cañavate, M L; Galdeano, A G; Izu, R; Díaz-Ramón, L; Raton, J A; Díaz-Pérez, J L

    2000-10-01

    Serum soluble interleukin-2 receptor (sIL-2R), intercellular adhesion molecule-1 (sICAM-1) and interleukin-10 (IL-10) have each been reported as useful markers for melanoma progression. To evaluate the clinical relevance of these three markers, we simultaneously analysed their serum levels in patients with melanoma. A longitudinal study with a 3-year follow-up was performed and different stages of the disease were considered. Mean values of sIL-2R were significantly higher than in normal controls in all stages and correlated with the disease progression. The prognosis of patients with levels > 529 U/ml of sIL-2R was significantly poorer than in patients with sIL-2R levels < 529 U/ml. Levels of sICAM-1 were also elevated in melanoma patients, specially at the time of the metastatic disease. Serum IL-10 levels were more frequently detectable in the patients that developed metastasis during follow-up, and the prognosis of patients with detectable IL-10 levels was significantly poorer than in those patients with IL-10 undetected levels. Statistical analysis based on Logistic and Cox regression models showed that only sex, stage and sIL-2R value are factors significantly associated with metastatic progression. Moreover, high levels of sIL-2R could be a risk factor for malignant progression in melanoma.

  17. Stromal interaction molecule 1 (STIM1) silencing inhibits tumor growth and promotes cell cycle arrest and apoptosis in hypopharyngeal carcinoma.

    PubMed

    Sun, Yuanhao; Cui, Xiaobo; Wang, Jun; Wu, Shuai; Bai, Yunfei; Wang, Yaping; Wang, Boqian; Fang, Jugao

    2015-05-01

    As an important pathway maintaining the balance of intracellular calcium (Ca(2+)), store-operated Ca(2+) entry (SOCE) is critical for cellular functions. Stromal interaction molecule 1 (STIM1), a key component of SOCE, plays a dual role as an endoplasmic reticulum Ca(2+) receptor and an SOCE exciter. Aberrant expression of STIM1 could be discovered in several human cancer cells. However, the role of STIM1 in regulating human hypopharyngeal carcinoma still remains unclear. Real-time polymerase chain reaction (PCR) was used to detect expression of STIM1 in human hypopharyngeal carcinoma cell line FaDu. STIM1 on FaDu cells was knocked down by lentiviral transduction method. The biological impacts after knocking down of STIM1 on FaDu cells were investigated in vitro and in vivo. The result of real-time PCR showed that STIM1 was expressed in FaDu cells. Lentiviral transduction efficiently downregulated the expression of STIM1 in FaDu cells at both mRNA and protein levels. Significant downregulation of STIM1 on FaDu cells inhibited cell proliferation, induced cell cycle arrest in G0/G1 phase, promoted cell apoptosis, and restrained cell growth rate. The antigrowth effect of STIM1 silencing was also discovered in FaDu hypopharyngeal tumor model. Our findings indicate that STIM1 is likely to become a new therapeutic target for hypopharyngeal carcinoma treatment.

  18. Identification of Human Junctional Adhesion Molecule 1 as a Functional Receptor for the Hom-1 Calicivirus on Human Cells

    PubMed Central

    Sandoval-Jaime, Carlos; Parra, Gabriel I.; Tin, Christine M.; Jones, Ronald W.; Soden, Jo; Barnes, Donna; Freeth, Jim; Smith, Alvin W.; Green, Kim Y.

    2017-01-01

    ABSTRACT The Hom-1 vesivirus was reported in 1998 following the inadvertent transmission of the animal calicivirus San Miguel sea lion virus to a human host in a laboratory. We characterized the Hom-1 strain and investigated the mechanism by which human cells could be infected. An expression library of 3,559 human plasma membrane proteins was screened for reactivity with Hom-1 virus-like particles, and a single interacting protein, human junctional adhesion molecule 1 (hJAM1), was identified. Transient expression of hJAM1 conferred susceptibility to Hom-1 infection on nonpermissive Chinese hamster ovary (CHO) cells. Virus infection was markedly inhibited when CHO cells stably expressing hJAM were pretreated with anti-hJAM1 monoclonal antibodies. Cell lines of human origin were tested for growth of Hom-1, and efficient replication was observed in HepG2, HuH7, and SK-CO15 cells. The three cell lines (of hepatic or intestinal origin) were confirmed to express hJAM1 on their surface, and clustered regularly interspaced short palindromic repeats/Cas9-mediated knockout of the hJAM1 gene in each line abolished Hom-1 propagation. Taken together, our data indicate that entry of the Hom-1 vesivirus into these permissive human cell lines is mediated by the plasma membrane protein hJAM1 as a functional receptor. PMID:28196955

  19. Kidney Injury Molecule-1 Protects against Gα12 Activation and Tissue Damage in Renal Ischemia-Reperfusion Injury

    PubMed Central

    Ismail, Ola Z.; Zhang, Xizhong; Wei, Junjun; Haig, Aaron; Denker, Bradley M.; Suri, Rita S.; Sener, Alp; Gunaratnam, Lakshman

    2016-01-01

    Ischemic acute kidney injury is a serious untreatable condition. Activation of the G protein α12 (Gα12) subunit by reactive oxygen species is a major cause of tissue damage during renal ischemia-reperfusion injury. Kidney injury molecule-1 (KIM-1) is a transmembrane glycoprotein that is highly up-regulated during acute kidney injury, but the physiologic significance of this up-regulation is unclear. Here, we report for the first time that Kim-1 inhibits Gα12 activation and protects mice against renal ischemia-reperfusion injury. We reveal that Kim-1 physically interacts with and inhibits cellular Gα12 activation after inflammatory stimuli, including reactive oxygen species, by blocking GTP binding to Gα12. Compared with Kim-1+/+ mice, Kim-1−/− mice exhibited greater Gα12 and downstream Src activation both in primary tubular epithelial cells after in vitro stimulation with H2O2 and in whole kidneys after unilateral renal artery clamping. Finally, we show that Kim-1–deficient mice had more severe kidney dysfunction and tissue damage after bilateral renal artery clamping, compared with wild-type mice. Our results suggest that KIM-1 is an endogenous protective mechanism against renal ischemia-reperfusion injury through inhibition of Gα12. PMID:25759266

  20. Folate deficiency and aberrant expression of cell adhesion molecule 1 are potential indicators of prognosis in laryngeal squamous cell carcinoma

    PubMed Central

    Chang, Hao; Ma, Min; Ma, Rui; Zhang, Chao; Zeng, Wei; Xing, Lu Qi

    2016-01-01

    The etiology of laryngeal squamous cell carcinoma (LSCC) has not yet been adequately examined. Therefore, the present study aimed to investigate the association between serum folate deficiency and abnormal expression of the cell adhesion molecule 1 (CADM1) protein in the progression of LSCC. Samples were collected from 60 patients with LSCC and 30 healthy people. Radioimmunoassays and immunohistochemical staining were performed to measure serum folate levels and CADM1 protein expression, respectively. The results demonstrated that CADM1 expression in LSCC specimens was significantly lower than in adjacent normal tissues (χ2=28.229, P<0.001), which was associated with histological differentiation and clinical stage (P=0.010 and 0.020, respectively). Levels of serum folate in patients with LSCC were significantly lower than those observed in healthy individuals (P=0.002). Furthermore, TSLCl expression and serum folate levels were positively correlated in LSCC (r=0.642, P=0.001). Thus, the present study determined that decreased CADM1 protein expression and low levels of serum folate were correlated with an increased severity of LSCC. PMID:28105160

  1. Association between the levels of urine kidney injury molecule-1 and the progression of acute kidney injury in the elderly

    PubMed Central

    Wang, Chunlin; Che, Xiajing; Shao, Xinghua; Xu, Yao; Ni, Zhaohui; Mou, Shan

    2017-01-01

    Background The factors influencing the prognosis of acute kidney injury (AKI) were analyzed in a group of elderly AKI patients to determine the markers of early prognosis. Methods A total of 258 patients were screened, and 201 patients were enrolled in the study. Eventually, 184 AKI patients were included in the study, including 79 elderly AKI patients (≥60 years old). During one year of follow-up, renal function changes were observed, and the risk factors that influenced the prognosis of AKI were analyzed. Results When AKI occurred, the urine kidney injury molecule-1 (uKIM-1) level was significantly higher in the progressive deterioration of renal function group than in the renal function stable group. The ROC curve analysis revealed that the area under the curve for poor progressive deterioration of renal function as predicted by the uKIM-1 level was 0.681. At a cutoff point of 2.46 ng/mg, the sensitivity was 71.9% and the specificity was 70.0%. In elderly AKI patients, uKIM-1 levels exceeding 2.46 ng/mg were positively associated with poor kidney prognosis. Conclusions Elderly AKI patients are at risk of developing progressive deterioration of renal function. In elderly AKI patients, the high uKIM-1 level may predict the prognosis of kidney function and may be used as an early screening indicator of poor kidney prognosis. PMID:28187124

  2. Circulating thrombomodulin and vascular cell adhesion molecule-1 and renal vascular lesion in patients with lupus nephritis.

    PubMed

    Yao, G H; Liu, Z H; Zhang, X; Zheng, C X; Chen, H P; Zeng, C H; Li, L S

    2008-08-01

    Currently, the detection of renal vascular lesions (VLS) in lupus nephritis (LN) mainly depends on biopsy examination, and lack surrogate biomarkers for clinical dynamic evaluation. The aim of the present study is to explore the correlation between circulatory endothelial damage biomarkers and VLS. Soluble E-selectin, thrombomodulin (TM) and vascular cell adhesion molecule-1 (VCAM-1) were measured by ELISA. TM and VCAM-1 levels both were significantly elevated in LN with VLS than in LN without VLS (P < 0.01). However, the serum E-selectin was not significantly changed in LN patients with and without VLS. A positive correlation was found between TM and serum creatinine (r = 0.617, P < 0.05) in patients with vascular lesions. In order to further analyse the relationship between TM level and severity degree of vascular lesions in LN patients, we subdivided the patients with vascular lesions into two groups: with thrombotic microangiopathy (TMA) and without TMA. TM level of the patients with TMA is significantly higher than those without TMA (P < 0.01). In conclusion, combined with renal pathological examination, monitoring the circulatory levels of TM and VCAM-1, can provide circulating biomarkers of VLS in LN patients.

  3. MicroRNA-221 controls expression of intercellular adhesion molecule-1 in epithelial cells in response to Cryptosporidium parvum infection

    PubMed Central

    Gong, Ai-Yu; Hu, Guoku; Zhou, Rui; Liu, Jun; Feng, Yaoyu; Soukup, Garrett A.; Chen, Xian-Ming

    2011-01-01

    Cryptosporidium parvum is a protozoan parasite that infects gastrointestinal epithelial cells and causes diarrheal disease in humans and animals globally. Pathological changes following C. parvum infection include crypt hyperplasia, a modest inflammatory reaction with increased infiltration of lymphocytes into intestinal mucosa. Expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1), on infected epithelial cell surfaces may facilitate adhesion and recognition of lymphocytes at infection sites. MicroRNAs (miRNAs) are small RNA molecules of 23 nucleotides that negatively regulate protein-coding gene expression via translational suppression or mRNA degradation. We recently reported that microRNA-221 (miR-221) regulates ICAM-1 translation through targeting the ICAM-1 3′-untranslated region (UTR). In this study, we tested the role of miR-221 in regulating ICAM-1 expression in epithelial cells in response to C. parvum infection using an in vitro model of human biliary cryptosporidiosis. Up-regulation of ICAM-1 at both message and protein levels was detected in epithelial cells following C. parvum infection. Inhibition of ICAM-1 transcription with actinomycin D could only partially block C. parvum-induced ICAM-1 expression at the protein level. Cryptosporidium parvum infection decreased miR-221 expression in infected epithelial cells. When cells were transfected with a luciferase reporter construct covering the miR-221 binding site in the ICAM-1 3′-UTR and then exposed to C. parvum, an enhanced luciferase activity was detected. Transfection of miR-221 precursor abolished C. parvum-stimulated ICAM-1 protein expression. In addition, expression of ICAM-1 on infected epithelial cells facilitated epithelial adherence of co-cultured Jurkat cells. These results indicate that miR-221-mediated translational suppression controls ICAM-1 expression in epithelial cells in response to C. parvum infection. PMID:21236259

  4. Prognostic value of soluble intercellular adhesion molecule-1 (s-ICAM-1) in HIV-infected children.

    PubMed

    Gaddi, E; Laucella, S; Balbaryski, J; Cantisano, C; Barboni, G; Candi, M; Giraudi, V

    2000-12-01

    Central events in the host defence system and immune-mediated damage are tightly regulated by cell adhesion molecules. Sera from 28 human immunodeficiency virus (HIV)-1 infected children divided into groups according to disease severity, six seroreverting (SR) children and 25 healthy controls were studied to detect the presence of soluble intercellular adhesion molecule-1 (s-ICAM-1). Soluble ICAM-1 levels were found to be significantly increased in HIV-infected children in comparison with SR children or healthy controls. Levels of soluble ICAM-1 were higher in patients with severe forms of HIV-infection than in those with a milder form of the disease. Significant differences in titers of s-ICAM-1 were recorded between SR children and HIV-infected children with mild disease or healthy controls. There was a significant correlation between s-ICAM-1 levels and the concentrations of beta 2 microglobulin (beta 2m) and, to a lesser extend, immunoglobulin A levels (IgA). Soluble ICAM-1 levels didn't change considerably in HIV-infected children in stable clinical conditions, independently of their clinical stage of the disease, during a follow-up period of 9-12 months. Conversely, s-ICAM-1 levels increased simultaneously with the appearance of new well-defined clinical disorders or decreased during the improvement of clinical conditions. A significant negative correlation was recorded between the titers of the s-ICAM-1 and the CD4(+) T-cell levels. These results suggest that the s-ICAM-1 might be another useful tool to evaluate disease progression.

  5. Structural organization and function of mouse photoreceptor ribbon synapses involve the immunoglobulin protein synaptic cell adhesion molecule 1.

    PubMed

    Ribic, Adema; Liu, Xinran; Crair, Michael C; Biederer, Thomas

    2014-03-01

    Adhesive interactions in the retina instruct the developmental specification of inner retinal layers. However, potential roles of adhesion in the development and function of photoreceptor synapses remain incompletely understood. This contrasts with our understanding of synapse development in the CNS, which can be guided by select adhesion molecules such as the Synaptic Cell Adhesion Molecule 1 (SynCAM 1/CADM1/nectin-like 2 protein). This immunoglobulin superfamily protein modulates the development and plasticity of classical excitatory synapses. We show here by immunoelectron microscopy and immunoblotting that SynCAM 1 is expressed on mouse rod photoreceptors and their terminals in the outer nuclear and plexiform layers in a developmentally regulated manner. Expression of SynCAM 1 on rods is low in early postnatal stages (P3-P7) but increases after eye opening (P14). In support of functional roles in the photoreceptors, electroretinogram recordings demonstrate impaired responses to light stimulation in SynCAM 1 knockout (KO) mice. In addition, the structural integrity of synapses in the OPL requires SynCAM 1. Quantitative ultrastructural analysis of SynCAM 1 KO retina measured fewer fully assembled, triadic rod ribbon synapses. Furthermore, rod synapse ribbons are shortened in KO mice, and protein levels of Ribeye, a major structural component of ribbons, are reduced in SynCAM 1 KO retina. Together, our results implicate SynCAM 1 in the synaptic organization of the rod visual pathway and provide evidence for novel roles of synaptic adhesion in the structural and functional integrity of ribbon synapses.

  6. SNPs in the neural cell adhesion molecule 1 gene (NCAM1) may be associated with human neural tube defects

    PubMed Central

    Deak, Kristen L.; Boyles, Abee L.; Etchevers, Heather C.; Melvin, Elizabeth C.; Siegel, Deborah G.; Graham, Felicia L.; Slifer, Susan H.; Enterline, David S.; George, Timothy M.; Vekemans, Michel; McClay, David; Bassuk, Alexander G.; Kessler, John A.; Linney, Elwood; Gilbert, John R.

    2011-01-01

    Neural tube defects (NTDs) are common birth defects, occurring in approximately 1/1,000 births; both genetic and environmental factors are implicated. To date, no major genetic risk factors have been identified. Throughout development, cell adhesion molecules are strongly implicated in cell–cell interactions, and may play a role in the formation and closure of the neural tube. To evaluate the role of neural cell adhesion molecule 1 (NCAM1) in risk of human NTDs, we screened for novel single-nucleotide polymorphisms (SNPs) within the gene. Eleven SNPs across NCAM1 were genotyped using TaqMan. We utilized a family-based approach to evaluate evidence for association and/or linkage disequilibrium. We evaluated American Caucasian simplex lumbosacral myelomeningocele families (n=132 families) using the family based association test (FBAT) and the pedigree disequilibrium test (PDT). Association analysis revealed a significant association between risk for NTDs and intronic SNP rs2298526 using both the FBAT test (P=0.0018) and the PDT (P=0.0025). Using the HBAT version of the FBAT to look for haplotype association, all pairwise comparisons with SNP rs2298526 were also significant. A replication study set, consisting of 72 additional families showed no significant association; however, the overall trend for overtransmission of the less common allele of SNP rs2298526 remained significant in the combined sample set. In addition, we analyzed the expression pattern of the NCAM1 protein in human embryos, and while NCAM1 is not expressed within the neural tube at the time of closure, it is expressed in the surrounding and later in differentiated neurons of the CNS. These results suggest variations in NCAM1 may influence risk for human NTDs. PMID:15883837

  7. Plasma zinc levels inversely correlate with vascular cell adhesion molecule-1 concentration in children with sickle cell disease.

    PubMed Central

    Kuvibidila, Solo R.; Sandoval, Manuel; Lao, Juan; Velez, Maria; Yu, Lolie; Ode, David; Gardner, Renée; Lane, Gerald; Warrier, Raj P.

    2006-01-01

    Zinc deficiency has been implicated in impaired cell-mediated immunity of children with sickle cell disease (SCD). However, its influence on the expression of vascular cell-adhesion molecule-1 (VCAM-1) on endothelial cells, a protein involved in vasoocclusion, has not been previously investigated. We therefore measured (soluble) sVCAM-1 and zinc in 76 SCD children and 96 non-SCD children, mean age 7.73 years and 11.24 years, respectively. Although mean zinc levels of both groups were within the normal range (approximately 14.5 micromol/l), 14.5 % of SCD and 11% of non-SCD children (without inflammation) had levels below normal (10.7 micromol/L). Mean sVCAM-1 concentrations of SCD children (837 microg/l) were significantly higher than those of controls (627 microg/l) (p < 0.001). Differences persisted after taking into account age, hemoglobin phenotype, and inflammation (alpha-l acid glycoprotein >l g/l and C-reactive protein >10 mg/I). sVCAM-1 negatively correlated with serum (r = -0.444) and red blood cells zinc (r = -0.242, p < 0.05) but not with acute-phase proteins. Mean sVCAM-1 tended to be higher in SCD children with than in those without a history of a health problem (infection, pain crisis or were transfused; not significant). Data suggest that zinc may modulate the clinical status of SCD children through VCAM-1 expression, and zinc supplementation may be beneficial in these patients. PMID:16916123

  8. Targeted disruption of carcinoembryonic antigen-related cell adhesion molecule 1 promotes diet-induced hepatic steatosis and insulin resistance.

    PubMed

    Xu, Elaine; Dubois, Marie-Julie; Leung, Nelly; Charbonneau, Alexandre; Turbide, Claire; Avramoglu, Rita Kohen; DeMarte, Luisa; Elchebly, Mounib; Streichert, Thomas; Lévy, Emile; Beauchemin, Nicole; Marette, André

    2009-08-01

    Carcinoembryonic antigen-related cell adhesion molecule 1 (CC1) is a cell adhesion molecule within the Ig superfamily. The Tyr-phosphorylated isoform of CC1 (CC1-L) plays an important metabolic role in the regulation of hepatic insulin clearance. In this report, we show that CC1-deficient (Cc1(-/-)) mice are prone to hepatic steatosis, as revealed by significantly elevated hepatic triglyceride and both total and esterified cholesterol levels compared with age-matched wild-type controls. Cc1(-/-) mice were also predisposed to lipid-induced hepatic steatosis and dysfunction as indicated by their greater susceptibility to store lipids and express elevated levels of enzymatic markers of liver damage after chronic feeding of a high-fat diet. Hepatic steatosis in the Cc1(-/-) mice was linked to a significant increase in the expression of key lipogenic (fatty acid synthase, acetyl CoA carboxylase) and cholesterol synthetic (3-hydroxy-3-methylglutaryl-coenzyme A reductase) enzymes under the control of sterol regulatory element binding proteins-1c and -2 transcription factors. Cc1(-/-) mice also exhibited impaired insulin clearance, glucose intolerance, liver insulin resistance, and elevated hepatic expression of the key gluconeogenic transcriptional activators peroxisome proliferator-activated receptor-gamma coactivator-1 and Forkhead box O1. Lack of CC1 also exacerbated both glucose intolerance and hepatic insulin resistance induced by high-fat feeding, but insulin clearance was not further deteriorated in the high-fat-fed Cc1(-/-) mice. In conclusion, our data indicate that CC1 is a key regulator of hepatic lipogenesis and that Cc1(-/-) mice are predisposed to liver steatosis, leading to hepatic insulin resistance and liver damage, particularly when chronically exposed to dietary fat.

  9. Leptin Resistance Contributes to Obesity in Mice with Null Mutation of Carcinoembryonic Antigen-related Cell Adhesion Molecule 1.

    PubMed

    Heinrich, Garrett; Russo, Lucia; Castaneda, Tamara R; Pfeiffer, Verena; Ghadieh, Hilda E; Ghanem, Simona S; Wu, Jieshen; Faulkner, Latrice D; Ergün, Süleyman; McInerney, Marcia F; Hill, Jennifer W; Najjar, Sonia M

    2016-05-20

    Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) promotes hepatic insulin clearance. Consistently, mice with null mutation of Ceacam1 (Cc1(-/-)) exhibit impaired insulin clearance with increased lipid production in liver and redistribution to white adipose tissue, leading to visceral obesity at 2 months of age. When the mutation is propagated on the C57/BL6J genetic background, total fat mass rises significantly with age, and glucose intolerance and systemic insulin resistance develop at 6 months of age. This study was carried out to determine the mechanisms underlying the marked increase in total fat mass in 6-month-old mutants. Indirect calorimetry analysis showed that Cc1(-/-) mice develop hyperphagia and a significant reduction in physical activity, in particular in the early hours of the dark cycle, during which energy expenditure is only slightly lower than in wild-type mice. They also exhibit increased triglyceride accumulation in skeletal muscle, due in part to incomplete fatty acid β-oxidation. Mechanistically, hypothalamic leptin signaling is reduced, as demonstrated by blunted STAT3 phosphorylation in coronal sections in response to an intracerebral ventricular injection of leptin. Hypothalamic fatty-acid synthase activity is also elevated in the mutants. Together, the data show that the increase in total fat mass in Cc1(-/-) mice is mainly attributed to hyperphagia and reduced spontaneous physical activity. Although the contribution of the loss of CEACAM1 from anorexigenic proopiomelanocortin neurons in the arcuate nucleus is unclear, leptin resistance and elevated hypothalamic fatty-acid synthase activity could underlie altered energy balance in these mice.

  10. Benzo[a]pyrene induces intercellular adhesion molecule-1 through a caveolae and aryl hydrocarbon receptor mediated pathway

    SciTech Connect

    Oesterling, Elizabeth; Toborek, Michal; Hennig, Bernhard

    2008-10-15

    Toxicologic and epidemiologic studies have linked benzo[a]pyrene (B[a]P) exposure with cardiovascular diseases such as atherosclerosis. The mechanisms of action leading to these diseases have not been fully understood. One key step in the development of atherosclerosis is vascular endothelial dysfunction, which is characterized by increased adhesiveness. To determine if B[a]P could lead to increased endothelial adhesiveness, the effects of B[a]P on human endothelial cell intercellular adhesion molecule-1 (ICAM-1) expression was investigated. B[a]P was able to increase ICAM-1 protein only after pretreatment with the aryl hydrocarbon receptor (AhR) agonist {beta}-naphthoflavone ({beta}-NF). Knockdown of AhR by siRNA or treatment with AhR antagonist {alpha}-naphthoflavone ({alpha}-NF) eliminated the induction of ICAM-1 from B[a]P, confirming the necessity of AhR in this process. Likewise, B[a]P only increased monocyte adhesion to the vascular endothelium when cells were pretreated with {beta}-NF. Experiments were done to define a signaling mechanism. B[a]P increased phosphorylation of MEK and p38-MAPK, and inhibitors to these proteins blunted the ICAM-1 induction. B[a]P was also able to increase AP-1 DNA binding and phosphorylation of cJun. Phosphorylation of cJun was disrupted by MEK and p38-MAPK inhibitors linking the signaling cascade. Finally, the importance of membrane microdomains, caveolae, was demonstrated by knockdown of the structural protein caveolin-1. Disruption of caveolae eliminated the B[a]P-induced ICAM-1 expression. These data suggest a possible pro-inflammatory mechanism of action of B[a]P involving caveolae, leading to increased vascular endothelial adhesiveness, and this inflammation may be a critical step in the development of B[a]P-induced atherosclerosis.

  11. Inducible expression of vascular cell adhesion molecule-1 by vascular smooth muscle cells in vitro and within rabbit atheroma.

    PubMed Central

    Li, H.; Cybulsky, M. I.; Gimbrone, M. A.; Libby, P.

    1993-01-01

    Vascular cell adhesion molecule-1 (VCAM-1), a mononuclear leukocyte adhesion molecule, is expressed in cultured vascular endothelial cells activated by cytokines and is induced in rabbit aortic endothelium in vivo within 1 week after initiation of an atherogenic diet. We now demonstrate that vascular smooth muscle cells can also express VCAM-1 in rabbit atherosclerotic lesions in vivo and in response to cytokines in vitro. Immunohistochemical staining of aortas from rabbits fed a 0.3% cholesterol-containing diet revealed that a portion of smooth muscle cells within intimal foam cell-rich lesions expressed VCAM-1. The intimal VCAM-1-expressing cells localized predominantly in regions above the internal elastic lamina. These VCAM-1-positive cells had the typical spindle shape of smooth muscle cells but had reduced alpha-actin expression in comparison to normal medial smooth muscle cells, and did not bear markers for endothelium, macrophages, and T cells. In culture, rabbit aortic smooth muscle cells expressed VCAM-1 mRNA and protein in a time- and concentration-dependent fashion when exposed to interferon-gamma or Gram-negative bacterial lipopolysaccharide. Cultured human vascular smooth muscle cells also expressed VCAM-1 mRNA and protein in response to lipopolysaccharide, interferon-gamma, and interleukin-4. The monokines interleukin-1 alpha and tumor necrosis factor-alpha did not induce VCAM-1 expression in either rabbit or human vascular smooth muscle cells. Inducible VCAM-1 expression by vascular smooth muscle cells in vivo during hypercholesterolemia and in vitro in response to certain cytokines suggests a broader range of VCAM-1 functions in vascular biology than heretofore appreciated. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:7504883

  12. Identification of the binding site in intercellular adhesion molecule 1 for its receptor, leukocyte function-associated antigen 1.

    PubMed Central

    Fisher, K L; Lu, J; Riddle, L; Kim, K J; Presta, L G; Bodary, S C

    1997-01-01

    Intercellular adhesion molecule 1 (ICAM-1, CD54) is a member of the Ig superfamily and is a counterreceptor for the beta 2 integrins: lymphocyte function-associated antigen 1 (LFA-1, CD11a/CD18), complement receptor 1 (MAC-1, CD11b/CD18), and p150,95 (CD11c/CD18). Binding of ICAM-1 to these receptors mediates leukocyte-adhesive functions in immune and inflammatory responses. In this report, we describe a cell-free assay using purified recombinant extracellular domains of LFA-1 and a dimeric immunoadhesin of ICAM-1. The binding of recombinant secreted LFA-1 to ICAM-1 is divalent cation dependent (Mg2+ and Mn2+ promote binding) and sensitive to inhibition by antibodies that block LFA-1-mediated cell adhesion, indicating that its conformation mimics that of LFA-1 on activated lymphocytes. We describe six novel anti-ICAM-1 monoclonal antibodies, two of which are function blocking. Thirty-five point mutants of the ICAM-1 immunoadhesin were generated and residues important for binding of monoclonal antibodies and purified LFA-1 were identified. Nineteen of these mutants bind recombinant LFA-1 equivalently to wild type. Sixteen mutants show a 66-2500-fold decrease in LFA-1 binding yet, with few exceptions, retain binding to the monoclonal antibodies. These mutants, along with modeling studies, define the LFA-1 binding site on ICAM-1 as residues E34, K39, M64, Y66, N68, and Q73, that are predicted to lie on the CDFG beta-sheet of the Ig fold. The mutant G32A also abrogates binding to LFA-1 while retaining binding to all of the antibodies, possibly indicating a direct interaction of this residue with LFA-1. These data have allowed the generation of a highly refined model of the LFA-1 binding site of ICAM-1. Images PMID:9188101

  13. FMC46, a cell protrusion-associated leukocyte adhesion molecule-1 epitope on human lymphocytes and thymocytes.

    PubMed

    Pilarski, L M; Turley, E A; Shaw, A R; Gallatin, W M; Laderoute, M P; Gillitzer, R; Beckman, I G; Zola, H

    1991-07-01

    In this report, we describe a 76-kDa glycoprotein recognized by mAb FMC46 that, by virtue of its concentration on cell protrusions involved in motility, may be important in lymphoid cell locomotion. FMC46 detects an epitope of the leukocyte adhesion molecule-1 (LAM-1), a member of the selecting family (LAM-1, Endothelial Leukocyte Adhesion Molecular-1 (ELAM-1), and Granule Membrane Protein-140 (GMP-140), that is expressed on LAM-1-transfected cell lines, is a glycosylation epitope based on its loss after culture in tunicamycin, and is closely related to the LAM-1.2 epitope. FMC46 is expressed at high density on the majority of CD45RA+ and CD45RO+ peripheral blood T cells (60 to 70%) and on a subset of thymocytes that includes the multinegative CD3- CD4- CD8- progenitor cells (100% FMC46hi) and the CD45R0- presumptive thymic generative lineage (70% FMC46hi). It appears at reduced density and frequency on CD45RA- thymocytes (50% FMC46lo), comprised mainly of death-committed thymocytes. Among thymic subsets defined by expression of CD4 and/or CD8, FMC46 is expressed at high density predominantly on a subset of single-positive cells and not on double-positive cells. These results suggest a fundamental role for LAM-1 in thymic development, with a high density preferentially expressed on cells involved in thymic generative processes and a low density on cells progressing to intrathymic death. A major subset of peripheral blood B cells and thymic B cells also express FMC46. Immunohistochemistry on frozen sections indicated strong staining in splenic follicles and around blood vessels, staining of the thymic medulla and subcapsular areas, and staining of the mantle zone of germinal centers of the lymph node. FMC46+ lymphocytes accumulated along high endothelial venules in the lymph node. On locomoting multinegative thymocytes, FMC46 is concentrated on the leading tip of extended processes, on pseudopods, and on ruffles, unlike the distribution of either CD44 or TQ1 (LAM 1

  14. Soluble intercellular adhesion molecule-1, D-lactate and diamine oxidase in patients with inflammatory bowel disease

    PubMed Central

    Song, Wei-Bing; Lv, Yong-Hui; Zhang, Zhen-Shu; Li, Ya-Nan; Xiao, Li-Ping; Yu, Xin-Pei; Wang, Yuan-Yuan; Ji, Hong-Li; Ma, Li

    2009-01-01

    AIM: To study the levels of serum soluble intercellular adhesion molecule-1 (sICAM-1), plasma D-lactate and diamine oxidase (DAO) in patients with inflammatory bowel disease (IBD), and the potential clinical significance. METHODS: Sixty-nine patients with IBD and 30 healthy controls were included in this study. The concentration of sICAM-1 was detected with enzyme-linked immunosorbent assay, the level of D-lactate and DAO was measured by spectroscopic analysis, and the number of white blood cells (WBC) was determined by routine procedure. RESULTS: The levels of sICAM-l, DAO, and WBC in IBD patients were significantly higher than those in the control group (P < 0.01). sICAM-l in IBD patients was found to be closely related to the levels of DAO and D-lactate (212.94 ± 69.89 vs 6.35 ± 2.35, P = 0.000), DAO 212.94 ± 69.89 vs 8.65 ± 3.54, P = 0.000) and WBC (212.94 ± 69.89 vs 7.40 ± 2.61, P = 0.000), but no significant difference was observed between patients with ulcerative colitis and patients with Crohn’s disease. The post-treatment levels of sICAM-l, D-lactate and WBC were significantly lower than before treatment (sICAM-l 206.57 ± 79.21 vs 146.21 ± 64.43, P = 0.000), (D-lactate 1.46 ± 0.94 vs 0.52 ± 0.32, P = 0.000) and (WBC 7.24 ± 0.2.33 vs 5.21 ± 3.21, P = 0.000). CONCLUSION: sICAM-1, D-lactate and DAO are closely related to the specific conditions of IBD, and thus could be used as a major diagnostic index. PMID:19701972

  15. Proceedings of the U.S. Geological Survey Eighth Biennial Geographic Information Science Workshop and first The National Map Users Conference, Denver, Colorado, May 10-13, 2011

    USGS Publications Warehouse

    Sieverling, Jennifer B.; Dietterle, Jeffrey

    2014-01-01

    The U.S. Geological Survey (USGS) is sponsoring the first The National Map Users Conference in conjunction with the eighth biennial Geographic Information Science (GIS) Workshop on May 10-13, 2011, in Lakewood, Colorado. The GIS Workshop will be held at the USGS National Training Center, located on the Denver Federal Center, Lakewood, Colorado, May 10-11. The National Map Users Conference will be held directly after the GIS Workshop at the Denver Marriott West, a convention hotel in the Lakewood, Colorado area, May 12-13. The National Map is designed to serve the Nation by providing geographic data and knowledge for government, industry, and public uses. The goal of The National Map Users Conference is to enhance communications and collaboration among the communities of users of and contributors to The National Map, including USGS, Department of the Interior, and other government GIS specialists and scientists, as well as the broader geospatial community. The USGS National Geospatial Program intends the conference to serve as a forum to engage users and more fully discover and meet their needs for the products and services of The National Map. The goal of the GIS Workshop is to promote advancement of GIS and related technologies and concepts as well as the sharing of GIS knowledge within the USGS GIS community. This collaborative opportunity for multi-disciplinary GIS and associated professionals will allow attendees to present and discuss a wide variety of geospatial-related topics. The Users Conference and Workshop collaboration will bring together scientists, managers, and data users who, through presentations, posters, seminars, workshops, and informal gatherings, will share accomplishments and progress on a variety of geospatial topics. During this joint event, attendees will have the opportunity to present or demonstrate their work; to develop their knowledge by attending hands-on workshops, seminars, and presentations given by professionals from USGS and

  16. The relationship between platelet endothelial cell adhesion molecule-1 and paraquat-induced lung injury in rabbits

    PubMed Central

    Shi, Jing; Hu, Chun-lin; Gao, Yu-feng; Liao, Xiao-xing; Xu, Hope

    2012-01-01

    BACKGROUND: Platelet endothelial cell adhesion molecule-1 (PECAM-1), also known as CD31, is mainly distributed in vascular endothelial cells. Studies have shown that PECAM-1 is a very significant indicator of angiogenesis, and has been used as an indicator for vascular endothelial cells. The present study aimed to explore the relationship between the expression of PECAM-1 and the degree of acute lung injury (ALI) and fibrosis in paraquat (PQ) induced lung injury in rabbits. METHODS: Thirty-six adult New Zealand rabbits were randomly divided into three groups (12 rabbits in each group) according to PQ dosage: 8 mg/kg (group A), 16 mg/kg (group B), and 32 mg/kg (group C). After PQ infusion, the rabbits were monitored for 7 days and then euthanized. The lungs were removed for histological evaluation. Masson staining was used to determine the degree of lung fibrosis (LF), and semi-quantitative immune-histochemistry analysis to determine the expression of PECAM-1. Pearson’s product-moment correlation analysis was performed to evaluate the relationship between the expression of PECAM-1 and the extent of lung injuries expressed by ALI score and degree of LF. RESULTS: Rabbits in the three groups showed apparent poisoning. The rabbits survived longer in group A than in groups B and C (6.47±0.99 days vs. 6.09±1.04 days vs. 4.77±2.04 days) (P<0.05). ALI score was lower in group A than in groups B and C (8.33±1.03 vs. 9.83±1.17 vs. 11.50±1.38) (P<0.05), and there was statistically significant difference between group B and group C (P=0.03). LF was slighter in group A than in groups B and C (31.09%±2.05 % vs. 34.37%±1.62 % vs. 36.54%±0.44%) (P<0.05), and there was statistically significant difference between group B and group C (P=0.026). The PEACAM-1 expression was higher in group A than in groups B and C (20.31%±0.70% vs. 19.34%±0.68% vs. 18.37%±0.46%) (P<0.05), and there was statistically significant difference between group B and group C (P=0.017). Pearson

  17. Keishibukuryogan (Gui-Zhi-Fu-Ling-Wan), a Kampo Formula, Decreases Disease Activity and Soluble Vascular Adhesion Molecule-1 in Patients with Rheumatoid Arthritis

    PubMed Central

    Nozaki, Kazuya; Hikiami, Hiroaki; Goto, Hirozo; Nakagawa, Takako; Shibahara, Naotoshi; Shimada, Yutaka

    2006-01-01

    An increasing death rate due to cardiovascular disease in patients with rheumatoid arthritis (RA) has been reported. Keishibukuryogan (KBG) is a traditional Chinese/Japanese (Kampo) formula that has been administered to patients with blood stagnation, e.g. thrombotic disease and atherosclerosis. The objective of this study was to evaluate the efficacy of KBG on disease activity and endothelial dysfunction in RA patients. Sixteen RA patients were enrolled and administered KBG (12 g per day) for 12 weeks in addition to continuing other drugs. The disease activity of RA was assessed by modified disease activity scores for 28 joints (DAS28). Plasma levels of adhesion molecules, soluble E-selectin (sE-selectin), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were evaluated. C-reactive protein (CRP), inflammatory cytokines (IL-1β, IL-6 and TNF-α) and lipid peroxide (LPO) were also evaluated. Fourteen patients completed the study. The disease activity of RA, tender joint count, swollen joint count and DAS28 decreased significantly. Among adhesion molecules, only sVCAM-1 decreased significantly. LPO also decreased significantly, whereas CRP and inflammatory cytokines remained unchanged. These results suggest that KBG has insufficient anti-inflammatory or immunomodulating effect but does have a beneficial effect on articular symptoms and a protective effect against endothelial dysfunction in RA patients. PMID:16951720

  18. Kinin B1 receptor regulates interactions between neutrophils and endothelial cells by modulating the levels of Mac-1, LFA-1 and intercellular adhesion molecule-1.

    PubMed

    Figueroa, Carlos D; Matus, Carola E; Pavicic, Francisca; Sarmiento, Jose; Hidalgo, Maria A; Burgos, Rafael A; Gonzalez, Carlos B; Bhoola, Kanti D; Ehrenfeld, Pamela

    2015-04-01

    Kinins are pro-inflammatory peptides that mimic the cardinal features of inflammation. We examined the concept that expression levels of endothelial intercellular adhesion molecule-1 (ICAM-1) and neutrophil integrins Mac-1 and LFA-1 are modulated by the kinin B1 receptor (B1R) agonist, Lys-des[Arg(9)]bradykinin (LDBK). Stimulation of endothelial cells with LDBK increased the levels of ICAM-1 mRNA transcripts/protein, and also of E-selectin and platelet endothelial adhesion molecule-1. ICAM-1 levels increased in a magnitude comparable with that produced by TNF-α. This stimulatory effect was reduced when endothelial cells, which had been previously transfected with a B1R small interfering RNA, were stimulated with LDBK, under comparable conditions. Similarly, LDBK produced a significant increase in protein levels of LFA-1 and Mac-1 integrins in human neutrophils, an effect that was reversed by pretreatment of cells with 10 µg/ml cycloheximide or a B1R antagonist. Functional experiments performed with post-confluent monolayers of endothelial cells stimulated with LDBK and neutrophils primed with TNF-α, and vice versa, resulted in enhanced adhesiveness between both cells. Neutralizing Abs to ICAM-1 and Mac-1 reduced the adhesion between them. Our results indicate that kinin B1R is a novel modulator that promotes adhesion of leukocytes to endothelial cells, critically enhancing the movement of neutrophils from the circulation to sites of inflammation.

  19. The 18-kDa Translocator Protein Inhibits Vascular Cell Adhesion Molecule-1 Expression via Inhibition of Mitochondrial Reactive Oxygen Species

    PubMed Central

    Joo, Hee Kyoung; Lee, Yu Ran; Kang, Gun; Choi, Sunga; Kim, Cuk-Seong; Ryoo, Sungwoo; Park, Jin Bong; Jeon, Byeong Hwa

    2015-01-01

    Translocator protein 18 kDa (TSPO) is a mitochondrial outer membrane protein and is abundantly expressed in a variety of organ and tissues. To date, the functional role of TSPO on vascular endothelial cell activation has yet to be fully elucidated. In the present study, the phorbol 12-myristate 13-acetate (PMA, 250 nM), an activator of protein kinase C (PKC), was used to induce vascular endothelial activation. Adenoviral TSPO overexpression (10–100 MOI) inhibited PMA-induced vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1) expression in a dose dependent manner. PMA-induced VCAM-1 expressions were inhibited by Mito-TEMPO (0.1–0.5 μM), a specific mitochondrial antioxidants, and cyclosporin A (1–5 μM), a mitochondrial permeability transition pore inhibitor, implying on an important role of mitochondrial reactive oxygen species (ROS) on the endothelial activation. Moreover, adenoviral TSPO overexpression inhibited mitochondrial ROS production and manganese superoxide dismutase expression. On contrasts, gene silencing of TSPO with siRNA increased PMA-induced VCAM-1 expression and mitochondrial ROS production. Midazolam (1–50 μM), TSPO ligands, inhibited PMA-induced VCAM-1 and mitochondrial ROS production in endothelial cells. These results suggest that mitochondrial TSPO can inhibit PMA-induced endothelial inflammation via suppression of VCAM-1 and mitochondrial ROS production in endothelial cells. PMID:26608360

  20. Amino Acid Sequences Mediating Vascular Cell Adhesion Molecule 1 Binding to Integrin Alpha 4: Homologous DSP Sequence Found for JC Polyoma VP1 Coat Protein

    PubMed Central

    Meyer, Michael Andrew

    2013-01-01

    The JC polyoma viral coat protein VP1 was analyzed for amino acid sequences homologies to the IDSP sequence which mediates binding of VLA-4 (integrin alpha 4) to vascular cell adhesion molecule 1. Although the full sequence was not found, a DSP sequence was located near the critical arginine residue linked to infectivity of the virus and binding to sialic acid containing molecules such as integrins (3). For the JC polyoma virus, a DSP sequence was found at residues 70, 71 and 72 with homology also noted for the mouse polyoma virus and SV40 virus. Three dimensional modeling of the VP1 molecule suggests that the DSP loop has an accessible site for interaction from the external side of the assembled viral capsid pentamer. PMID:24147211

  1. Platelet-endothelial cell adhesion molecule-1 (PECAM-1/CD31) tyrosine phosphorylation state changes during vasculogenesis in the murine conceptus.

    PubMed Central

    Pinter, E.; Barreuther, M.; Lu, T.; Imhof, B. A.; Madri, J. A.

    1997-01-01

    Vasculogenesis, the differentiation of mesodermal cells to angioblasts and the subsequent formation of blood islands and blood vessels by angioblasts in the conceptus, is a dynamic process modulated, in part, by cell-extracellular matrix and cell-cell interactions in the presence of a variety of growth factors and morphogens. In this report we demonstrate differential tyrosine phosphorylation of platelet-endothelial cell adhesion molecule-1 (PECAM-1) during the formation of blood islands and vessels from clusters of extraembryonic and embryonic angioblasts in the murine conceptus. In addition, we identify the phosphorylation of a particular tyrosine residue in the PECAM-1 cytoplasmic domain, Tyr686, which has the potential of mediating binding to Src homology 2 domain-containing proteins, affecting PECAM-1 cellular localization and endothelial cell migration. Images Figure 1 Figure 2 Figure 3 PMID:9137078

  2. Amino Acid Sequences Mediating Vascular Cell Adhesion Molecule 1 Binding to Integrin Alpha 4: Homologous DSP Sequence Found for JC Polyoma VP1 Coat Protein.

    PubMed

    Meyer, Michael Andrew

    2013-01-01

    The JC polyoma viral coat protein VP1 was analyzed for amino acid sequences homologies to the IDSP sequence which mediates binding of VLA-4 (integrin alpha 4) to vascular cell adhesion molecule 1. Although the full sequence was not found, a DSP sequence was located near the critical arginine residue linked to infectivity of the virus and binding to sialic acid containing molecules such as integrins (3). For the JC polyoma virus, a DSP sequence was found at residues 70, 71 and 72 with homology also noted for the mouse polyoma virus and SV40 virus. Three dimensional modeling of the VP1 molecule suggests that the DSP loop has an accessible site for interaction from the external side of the assembled viral capsid pentamer.

  3. Monocyte adhesion to endothelium in simian immunodeficiency virus-induced AIDS encephalitis is mediated by vascular cell adhesion molecule-1/alpha 4 beta 1 integrin interactions.

    PubMed Central

    Sasseville, V. G.; Newman, W.; Brodie, S. J.; Hesterberg, P.; Pauley, D.; Ringler, D. J.

    1994-01-01

    Because the mechanisms associated with recruitment of monocytes to brain in AIDS encephalitis are unknown, we used tissues from rhesus monkeys infected with simian immunodeficiency virus (SIV) to examine the relative contributions of various adhesion pathways in mediating monocyte adhesion to endothelium from encephalitic brain. Using a modified Stamper and Woodruff tissue adhesion assay, we found that the human monocytic cell lines, THP-1 and U937, and the B cell line, Ramos, preferentially bound to brain vessels from monkeys with AIDS encephalitis. Using a combined tissue adhesion/immunohistochemistry approach, these cells only bound to vessels expressing vascular cell adhesion molecule-1 (VCAM-1). Furthermore, pretreatment of tissues with antibodies to VCAM-1 or cell lines with antibodies to VLA-4 (CD49d) inhibited adhesion by more than 70%. Intercellular adhesion molecule-1 (ICAM-1)/beta 2 integrin interactions were not significant in mediating cell adhesion to the vasculature in encephalitic simian brain using a cell line (JY) capable of binding rhesus monkey ICAM-1. In addition, selectin-mediated interactions did not significantly contribute to cell binding to encephalitic brain as there was no immunohistochemical expression of E-selectin and P-selectin in either normal or encephalitic brain, nor was there a demonstrable adhesive effect from L-selectin using L-selectin-transfected 300.19 cells on simian encephalitic brain. These results demonstrate that using the tissue adhesion assay, THP-1, U937, and Ramos cells bind to vessels in brain from animals with AIDS encephalitis using VCAM-1/alpha 4 beta 1 integrin interactions and suggest that VCAM-1 and VLA-4 may be integral for monocyte recruitment to the central nervous system during the development of AIDS encephalitis. Images Figure 1 PMID:7507300

  4. Micromanipulation of adhesion of phorbol 12-myristate-13-acetate-stimulated T lymphocytes to planar membranes containing intercellular adhesion molecule-1.

    PubMed Central

    Tözeren, A; Mackie, L H; Lawrence, M B; Chan, P Y; Dustin, M L; Springer, T A

    1992-01-01

    This paper presents an analytical and experimental methodology to determine the physical strength of cell adhesion to a planar membrane containing one set of adhesion molecules. In particular, the T lymphocyte adhesion due to the interaction of the lymphocyte function associated molecule 1 on the surface of the cell, with its counter-receptor, intercellular adhesion molecule-1 (ICAM-1), on the planar membrane, was investigated. A micromanipulation method and mathematical analysis of cell deformation were used to determine (a) the area of conjugation between the cell and the substrate and (b) the energy that must be supplied to detach a unit area of the cell membrane from its substrate. T lymphocytes stimulated with phorbol 12-myristate-13-acetate (PMA) conjugated strongly with the planar membrane containing purified ICAM-1. The T lymphocytes attached to the planar membrane deviated occasionally from their round configuration by extending pseudopods but without changing the size of the contact area. These adherent cells were dramatically deformed and then detached when pulled away from the planar membrane by a micropipette. Detachment occurred by a gradual decrease in the radius of the contact area. The physical strength of adhesion between a PMA-stimulated T lymphocyte and a planar membrane containing 1,000 ICAM-1 molecules/micron 2 was comparable to the strength of adhesion between a cytotoxic T cell and its target cell. The comparison of the adhesive energy density, measured at constant cell shape, with the model predictions suggests that the physical strength of cell adhesion may increase significantly when the adhesion bonds in the contact area are immobilized by the actin cytoskeleton. Images FIGURE 2 FIGURE 4 FIGURE 5 FIGURE 8 FIGURE 9 PMID:1358239

  5. Short-term high-fat diet alters postprandial glucose metabolism and circulating vascular cell adhesion molecule-1 in healthy males.

    PubMed

    Numao, Shigeharu; Kawano, Hiroshi; Endo, Naoya; Yamada, Yuka; Takahashi, Masaki; Konishi, Masayuki; Sakamoto, Shizuo

    2016-08-01

    Short-term intake of a high-fat diet aggravates postprandial glucose metabolism; however, the dose-response relationship has not been investigated. We hypothesized that short-term intake of a eucaloric low-carbohydrate/high-fat diet (LCHF) would aggravate postprandial glucose metabolism and circulating adhesion molecules in healthy males. Seven healthy young males (mean ± SE; age: 26 ± 1 years) consumed either a eucaloric control diet (C, approximately 25% fats), a eucaloric intermediate-carbohydrate/intermediate-fat diet (ICIF, approximately 50% fats), or an LCHF (approximately 70% fats) for 3 days. An oral meal tolerance test (MTT) was performed after the 3-day dietary intervention. The concentrations of plasma glucose, insulin, glucagon-like peptide-1 (GLP-1), intercellular adhesion molecule-1, and vascular cell adhesion molecule-1 (VCAM-1) were determined at rest and during MTT. The incremental area under the curve (iAUC) of plasma glucose concentration during MTT was significantly higher in LCHF than in C (P = 0.009). The first-phase insulin secretion indexes were significantly lower in LCHF than in C (P = 0.04). Moreover, the iAUC of GLP-1 and VCAM-1 concentrations was significantly higher in LCHF than in C (P = 0.014 and P = 0.04, respectively). The metabolites from ICIF and C were not significantly different. In conclusion, short-term intake of eucaloric diet containing a high percentage of fats in healthy males excessively increased postprandial glucose and VCAM-1 concentrations and attenuated first-phase insulin release.

  6. Compensatory changes in CYP expression in three different toxicology mouse models: CAR-null, Cyp3a-null, and Cyp2b9/10/13-null mice

    PubMed Central

    Kumar, Ramiya; Mota, Linda C.; Litoff, Elizabeth J.; Rooney, John P.; Boswell, W. Tyler; Courter, Elliott; Henderson, Charles M.; Hernandez, Juan P.; Corton, J. Christopher; Moore, David D.

    2017-01-01

    Targeted mutant models are common in mechanistic toxicology experiments investigating the absorption, metabolism, distribution, or elimination (ADME) of chemicals from individuals. Key models include those for xenosensing transcription factors and cytochrome P450s (CYP). Here we investigated changes in transcript levels, protein expression, and steroid hydroxylation of several xenobiotic detoxifying CYPs in constitutive androstane receptor (CAR)-null and two CYP-null mouse models that have subfamily members regulated by CAR; the Cyp3a-null and a newly described Cyp2b9/10/13-null mouse model. Compensatory changes in CYP expression that occur in these models may also occur in polymorphic humans, or may complicate interpretation of ADME studies performed using these models. The loss of CAR causes significant changes in several CYPs probably due to loss of CAR-mediated constitutive regulation of these CYPs. Expression and activity changes include significant repression of Cyp2a and Cyp2b members with corresponding drops in 6α- and 16β-testosterone hydroxylase activity. Further, the ratio of 6α-/15α-hydroxylase activity, a biomarker of sexual dimorphism in the liver, indicates masculinization of female CAR-null mice, suggesting a role for CAR in the regulation of sexually dimorphic liver CYP profiles. The loss of Cyp3a causes fewer changes than CAR. Nevertheless, there are compensatory changes including gender-specific increases in Cyp2a and Cyp2b. Cyp2a and Cyp2b were down-regulated in CAR-null mice, suggesting activation of CAR and potentially PXR following loss of the Cyp3a members. However, the loss of Cyp2b causes few changes in hepatic CYP transcript levels and almost no significant compensatory changes in protein expression or activity with the possible exception of 6α-hydroxylase activity. This lack of a compensatory response in the Cyp2b9/10/13-null mice is probably due to low CYP2B hepatic expression, especially in male mice. Overall, compensatory and

  7. Serum activated leukocyte cell adhesion molecule and intercellular adhesion molecule-1 in patients with gastric cancer: Can they be used as biomarkers?

    PubMed

    Erturk, Kayhan; Tastekin, Didem; Bilgin, Elif; Serilmez, Murat; Bozbey, Hamza Ugur; Sakar, Burak

    2016-02-01

    Cellular adhesion molecules might be used as markers in diagnosis and prognosis in some types of malignant tumors. The purpose of this study was to determine the clinical significance of the serum levels of activated leukocyte cell adhesion molecule-1 (ALCAM) and intercellular adhesion molecule-1 (ICAM-1) in gastric cancer (GC) patients. Fifty-eight GC patients and 20 age- and sex-matched healthy controls were enrolled into this study. Pretreatment serum markers were determined by the solid-phase sandwich enzyme-linked immunosorbent assay (ELISA). The median age at diagnosis was 59.5 years (range 32-82 years). Tumor localizations of the majority of the patients were antrum (n=42, 72.4%) and tumor histopathologies of the majority of the patients were diffuse (n=43, 74.1%). The majority of the patients had stage IV disease (n=41, 70.7%). Thirty six (62.1%) patients had lymph node involvement. The median follow-up time was 66 months (range 1-97.2 months). At the end of the observation period, 26 patients (44.8%) were dead. The median survival for all patients was 21.4±5 months (%95 CI, 11.5-31.3). The 1-year survival rates were 66.2%. The baseline serum ALCAM levels of the patients were significantly higher than those of the controls (p=0.001). There was no significant difference in the serum levels of ICAM-1 between the patients and controls (p=0.232). No significant correlation was detected between the levels of the serum markers and other clinical parameters (p>0.05). Tumor localization (p=0.03), histopathology (p=0.05), and response to chemotherapy (p=0.003) had prognostic factors on survival. Neither serum ALCAM levels nor serum ICAM-1 levels were identified to have a prognostic role on overall survival (ICAM-1 p=0.6, ALCAM p=0.25). In conclusion, serum levels of ALCAM were found to have diagnostic value in GC patients.

  8. Sesamin attenuates intercellular cell adhesion molecule-1 expression in vitro in TNF-alpha-treated human aortic endothelial cells and in vivo in apolipoprotein-E-deficient mice.

    PubMed

    Wu, Wen-Huey; Wang, Shu-Huei; Kuan, I-I; Kao, Ya-Shi; Wu, Pei-Jhen; Liang, Chan-Jung; Chien, Hsiung-Fei; Kao, Chiu-Hua; Huang, Ching-Jang; Chen, Yuh-Lien

    2010-09-01

    Sesame lignans have antioxidative and anti-inflammatory properties. We focused on the effects of the lignans sesamin and sesamol on the expression of endothelial-leukocyte adhesion molecules in tumor necrosis factor-alpha (TNF-alpha)-treated human aortic endothelial cells (HAECs). When HAECs were pretreated with sesamin (10 or 100 microM), the TNF-alpha-induced expression of intercellular cell adhesion molecule-1 (ICAM-1) was significantly reduced (35 or 70% decrease, respectively) by Western blotting. Sesamol was less effective at inhibiting ICAM-1 expression (30% decrease at 100 microM). Sesamin and sesamol reduced the marked TNF-alpha-induced increase in human antigen R (HuR) translocation and the interaction between HuR and the 3'UTR of ICAM-1 mRNA. Both significantly reduced the binding of monocytes to TNF-alpha-stimulated HAECs. Sesamin significantly attenuated TNF-alpha-induced ICAM-1 expression and cell adhesion by downregulation of extracellular signal-regulated kinase 1/2 and p38. Furthermore, in vivo, sesamin attenuated intimal thickening and ICAM-1 expression seen in aortas of apolipoprotein-E-deficient mice. Taken together, these data suggest that sesamin inhibits TNF-alpha-induced extracellular signal-regulated kinase/p38 phosphorylation, nuclear translocation of NF-kappaB p65, cytoplasmic translocalization of HuR and thereby suppresses ICAM-1 expression, resulting in reduced adhesion of leukocytes. These results also suggest that sesamin may prevent the development of atherosclerosis and inflammatory responses.

  9. Epstein-Barr Virus–induced Molecule 1 Ligand Chemokine Is Expressed by Dendritic Cells in Lymphoid Tissues and Strongly Attracts Naive T Cells and Activated B Cells

    PubMed Central

    Ngo, Vu N.; Lucy Tang, H.; Cyster, Jason G.

    1998-01-01

    Movement of T and B lymphocytes through secondary lymphoid tissues is likely to involve multiple cues that help the cells navigate to appropriate compartments. Epstein-Barr virus– induced molecule 1 (EBI-1) ligand chemokine (ELC/MIP3β) is expressed constitutively within lymphoid tissues and may act as such a guidance cue. Here, we have isolated mouse ELC and characterized its expression pattern and chemotactic properties. ELC is expressed constitutively in dendritic cells within the T cell zone of secondary lymphoid tissues. Recombinant ELC was strongly chemotactic for naive (L-selectinhi) CD4 T cells and for CD8 T cells and weakly attractive for resting B cells and memory (L-selectinlo) CD4 T cells. After activation through the B cell receptor, the chemotactic response of B cells was enhanced. Like its human counterpart, murine ELC stimulated cells transfected with EBI-1/CC chemokine receptor 7 (CCR7). Our findings suggest a central role for ELC in promoting encounters between recirculating T cells and dendritic cells and in the migration of activated B cells into the T zone of secondary lymphoid tissues. PMID:9653094

  10. αdβ2 Integrin Is Expressed on Human Eosinophils and Functions as an Alternative Ligand for Vascular Cell Adhesion Molecule 1 (VCAM-1)

    PubMed Central

    Grayson, Mitchell H.; Van der Vieren, Monica; Sterbinsky, Sherry A.; Michael Gallatin, W.; Hoffman, Patricia A.; Staunton, Donald E.; Bochner, Bruce S.

    1998-01-01

    The β2 family of integrins, CD11a, CD11b, CD11c, and αd, are expressed on most leukocytes. We show that the newest member of this family, αd, is expressed on human eosinophils in peripheral blood, and surface expression can be upregulated within minutes by phorbol ester or calcium ionophore A23187. Culture of eosinophils with interleukin 5 (IL-5) leads to a two- to fourfold increase in αd levels by 3–7 d without a change in α4 integrin expression. Eosinophils isolated from late phase bronchoalveolar lavage fluids express αd at levels similar to that seen after 3 d of IL-5 culture. Regarding αdβ2 ligands, in both freshly isolated and IL-5–cultured eosinophils, as well as αdβ2-transfected Chinese hamster ovary cells, αdβ2 can function as a ligand for vascular cell adhesion molecule 1 (VCAM-1). This conclusion is based on the ability of monoclonal antibodies to αd, β2, or VCAM-1 to block cell attachment in static adhesion assays. In experiments with eosinophils, the relative contribution of αdβ2 integrin– mediated adhesion is enhanced after IL-5 culture. These experiments demonstrate that αdβ2 is an alternative ligand for VCAM-1, and this integrin may play a role in eosinophil adhesion to VCAM-1 in states of chronic inflammation. PMID:9841932

  11. Magnolol reduced TNF-α-induced vascular cell adhesion molecule-1 expression in endothelial cells via JNK/p38 and NF-κB signaling pathways.

    PubMed

    Liang, Chan-Jung; Lee, Chiang-Wen; Sung, Hsin-Ching; Chen, Yung-Hsiang; Wang, Shu-Huei; Wu, Pei-Jhen; Chiang, Yao-Chang; Tsai, Jaw-Shiun; Wu, Chau-Chung; Li, Chi-Yuan; Chen, Yuh-Lien

    2014-01-01

    Expression of cell adhesion molecules by the endothelium and the attachment of leukocytes to these cells play major roles in inflammation and cardiovascular disorders. Magnolol, a major active component of Magnolia officinalis, has antioxidative and anti-inflammatory properties. In the present study, the effects of magnolol on the expression of vascular cell adhesion molecule-1 (VCAM-1) in human aortic endothelial cells (HAECs) and the related mechanisms were investigated. TNF-α induced VCAM-1 protein expression and mRNA stability were significantly decreased in HAECs pre-treated with magnolol. Magnolol significantly reduced the phosphorylation of ERK, JNK, and p38 in TNF-α-treated HAECs. The decrease in VCAM-1 expression in response to TNF-α treatment was affected by JNK and p38 inhibitors, not by an ERK inhibitor. Magnolol also attenuates NF-κB activation and the translocation of HuR (an RNA binding protein) in TNF-α-stimulated HAECs. The VCAM-1 expression was weaker in the aortas of TNF-α-treated apo-E deficient mice with magnolol treatment. These data demonstrate that magnolol inhibits TNF-α-induced JNK/p38 phosphorylation, HuR translocation, NF-κB activation, and thereby suppresses VCAM-1 expression resulting in reduced leukocyte adhesion. Taken together, these results suggest that magnolol has an anti-inflammatory property and may play an important role in the prevention of atherosclerosis and inflammatory responses.

  12. Transfected HEK293 Cells Expressing Functional Recombinant Intercellular Adhesion Molecule 1 (ICAM-1) – A Receptor Associated with Severe Plasmodium falciparum Malaria

    PubMed Central

    Bengtsson, Anja; Joergensen, Louise; Barbati, Zachary R.; Craig, Alister; Hviid, Lars; Jensen, Anja T. R.

    2013-01-01

    Intercellular adhesion molecule 1 (ICAM-1) is a membrane-bound glycoprotein expressed on endothelial cells and cells of the immune system. Human ICAM-1 mediates adhesion and migration of leucocytes, and is implicated in inflammatory pathologies, autoimmune diseases and in many cancer processes. Additionally, ICAM-1 acts as receptor for pathogens like human rhinovirus and Plasmodium falciparum malaria parasites. A group of related P. falciparum erythrocyte membrane protein 1 (PfEMP1) domains, the DBLβ, mediates ICAM-1 binding of P. falciparum-infected erythrocytes. This ICAM‑1-binding phenotype has been suggested to be involved in the development of cerebral malaria. However, more studies identifying cross-reactive antibody and ICAM-1-binding epitopes and the establishment of a clinical link between DBLβ expression and e.g. cerebral malaria are needed before the DBLβ domains can be put forward as vaccine candidates and go into clinical trials. Such studies require availability of functional recombinant ICAM-1 in large quantities. In this study, we compared recombinant ICAM-1 expressed in HEK293 and COS-7 cells with mouse myeloma NS0 ICAM-1 purchased from a commercial vendor in terms of protein purity, yield, fold, ability to bind DBLβ, and relative cost. We present a HEK293 cell-based, high-yield expression and purification scheme for producing inexpensive, functional ICAM‑1. ICAM-1 expressed in HEK293 is applicable to malaria research and can also be useful in other research fields. PMID:23936131

  13. Stromal Interaction Molecule 1 (STIM1) Regulates ATP-sensitive Potassium (KATP) and Store-operated Ca(2+) Channels in MIN6 β-Cells.

    PubMed

    Leech, Colin A; Kopp, Richard F; Nelson, Heather A; Nandi, Jyotirmoy; Roe, Michael W

    2017-02-10

    Stromal interaction molecule 1 (STIM1) regulates store-operated Ca(2+) entry (SOCE) and other ion channels either as an endoplasmic reticulum Ca(2+)-sensing protein or when present in the plasma membrane. However, the role of STIM1 in insulin-secreting β-cells is unresolved. We report that lowering expression of STIM1, the gene that encodes STIM1, in insulin-secreting MIN6 β-cells with RNA interference inhibits SOCE and ATP-sensitive K(+) (KATP) channel activation. The effects of STIM1 knockdown were reversed by transduction of MIN6 cells with an adenovirus gene shuttle vector that expressed human STIM1 Immunoprecipitation studies revealed that STIM1 binds to nucleotide binding fold-1 (NBF1) of the sulfonylurea receptor 1 (SUR1) subunit of the KATP channel. Binding of STIM1 to SUR1 was enhanced by poly-lysine. Our data indicate that SOCE and KATP channel activity are regulated by STIM1. This suggests that STIM1 is a multifunctional signaling effector that participates in the control of membrane excitability and Ca(2+) signaling events in β-cells.

  14. Artemether Combined with shRNA Interference of Vascular Cell Adhesion Molecule-1 Significantly Inhibited the Malignant Biological Behavior of Human Glioma Cells

    PubMed Central

    Wang, Ping; Xue, Yi-Xue; Yao, Yi-Long; Yu, Bo; Liu, Yun-Hui

    2013-01-01

    Artemether is the derivative extracted from Chinese traditional herb and originally used for malaria. Artemether also has potential therapeutic effects against tumors. Vascular cell adhesion molecule-1 (VCAM-1) is an important cell surface adhesion molecule associated with malignancy of gliomas. In this work, we investigated the role and mechanism of artemether combined with shRNA interference of VCAM-1 (shRNA-VCAM-1) on the migration, invasion and apoptosis of glioma cells. U87 human glioma cells were treated with artemether at various concentrations and shRNA interfering technology was employed to silence the expression of VCAM-1. Cell viability, migration, invasiveness and apoptosis were assessed with MTT, wound healing, Transwell and Annexin V-FITC/PI staining. The expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and phosphorylated Akt (p-Akt) was checked by Western blot assay. Results showed that artemether and shRNA-VCAM-1 not only significantly inhibited the migration, invasiveness and expression of MMP-2/9 and p-Akt, but also promoted the apoptosis of U87 cells. Combined treatment of both displayed the maximum inhibitory effects on the malignant biological behavior of glioma cells. Our work revealed the potential therapeutic effects of artemether and antiVCAM-1 in the treatments of gliomas. PMID:23593320

  15. Urinary calprotectin, kidney injury molecule-1, and neutrophil gelatinase-associated lipocalin for the prediction of adverse outcome in pediatric acute kidney injury.

    PubMed

    Westhoff, Jens H; Seibert, Felix S; Waldherr, Sina; Bauer, Frederic; Tönshoff, Burkhard; Fichtner, Alexander; Westhoff, Timm H

    2017-04-14

    Early identification of patients with acute kidney injury (AKI) being at high risk for adverse outcome can influence medical treatment. This study compares urinary calprotectin, kidney injury molecule-1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) for their performance in predicting mortality and need for renal replacement therapy (RRT) in pediatric AKI patients. Urinary biomarker concentrations were assessed prospectively in 141 subjects aged 0-18 years including 55 patients with established AKI according to pediatric Risk, Injury, Failure, Loss, and End-stage kidney disease (pRIFLE) criteria, 27 patients without AKI, and 59 healthy children. Within the AKI group, receiver operating characteristic (ROC) curve analysis revealed moderate to poor performance of calprotectin and KIM-1 in the prediction of 30-day mortality (calprotectin area under the curve (AUC) 0.55; KIM-1 AUC 0.55) and 3-month mortality (calprotectin AUC 0.61; KIM-1 AUC 0.60) and fair performance in the prediction of RRT requirement (calprotectin AUC 0.72; KIM-1 AUC 0.71). Urinary NGAL showed good performance in predicting 30-day (AUC 0.79) and 3-month (AUC 0.81) mortality and moderate performance in predicting RRT (AUC 0.61).

  16. Characterization and functional analysis of the expression of intercellular adhesion molecule-1 in human papillomavirus-related disease of cervical keratinocytes.

    PubMed Central

    Coleman, N.; Greenfield, I. M.; Hare, J.; Kruger-Gray, H.; Chain, B. M.; Stanley, M. A.

    1993-01-01

    We have investigated the expression of intercellular adhesion molecule-1 (ICAM-1) in squamous neoplasia of the cervix and have noted a significant induction of the molecule in high-grade intra-epithelial lesions. Using monolayer and organotypic in vitro tissue culture systems, we have shown that there is no constitutive ICAM-1 expression on cervical keratinocytes immortalized but not transformed by human papillomavirus type 16, whereas two human papillomaviruses type 16 containing and fully transformed cervical keratinocyte lines do constitutively express the molecule. All cell types, including human papillomavirus-negative normal cervical keratinocytes, can be induced to up-regulate their expression of ICAM-1 by pro-inflammatory cytokines such as interferon-gamma. In addition, we have used an in vitro adhesion assay to show that ICAM-1:lymphocyte function antigen-1 interaction is functionally important in lymphocyte binding to cervical keratinocytes, suggesting a role for ICAM-1 in retaining and enabling functional activity of lymphocytes in the cervix in intraepithelial neoplasia. Images Figure 1 Figure 2 Figure 5 Figure 9 PMID:8102029

  17. Inside-out Signaling Promotes Dynamic Changes in the Carcinoembryonic Antigen-related Cellular Adhesion Molecule 1 (CEACAM1) Oligomeric State to Control Its Cell Adhesion Properties*

    PubMed Central

    Patel, Prerna C.; Lee, Hannah S. W.; Ming, Aaron Y. K.; Rath, Arianna; Deber, Charles M.; Yip, Christopher M.; Rocheleau, Jonathan V.; Gray-Owen, Scott D.

    2013-01-01

    Cell-cell contacts are fundamental to multicellular organisms and are subject to exquisite levels of control. The carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) can engage in both cis-homophilic (parallel) oligomerization and trans-homophilic (anti-parallel) binding. In this study, we establish that the CEACAM1 transmembrane domain has a propensity to form cis-dimers via the transmembrane-embedded 432GXXXG436 motif and that this basal state is overcome when activated calmodulin binds to the CEACAM1 cytoplasmic domain. Although mutation of the 432GXXXG436 motif reduced CEACAM1 oligomerization, it did not affect surface localization of the receptor or influence CEACAM1-dependent cellular invasion by the pathogenic Neisseria. The mutation did, however, have a striking effect on CEACAM1-dependent cellular aggregation, increasing both the kinetics of cell-cell association and the size of cellular aggregates formed. CEACAM1 association with tyrosine kinase c-Src and tyrosine phosphatases SHP-1 and SHP-2 was not affected by the 432GXXXG436 mutation, consistent with their association with the monomeric form of wild type CEACAM1. Collectively, our results establish that a dynamic oligomer-to-monomer shift in surface-expressed CEACAM1 facilitates trans-homophilic binding and downstream effector signaling. PMID:24005674

  18. Elevation of soluble intercellular adhesion molecule-1 levels, but not angiopoietin 2, in the plasma of human immunodeficiency virus-infected African women with clinical Kaposi sarcoma.

    PubMed

    Graham, Susan M; Rajwans, Nimerta; Richardson, Barbra A; Jaoko, Walter; McClelland, R Scott; Overbaugh, Julie; Liles, W Conrad

    2014-10-01

    Circulating levels of endothelial activation biomarkers are elevated in during infection with human immunodeficiency virus 1 (HIV-1) and may also be increased in Kaposi sarcoma (KS). We compared 23 HIV-1-seropositive women with clinically diagnosed KS with 46 randomly selected controls matched for visit year, CD4 count, and antiretroviral therapy status. Conditional logistic regression was used to identify differences between cases and controls. The odds of clinical KS increased with increasing plasma viral load and with intercellular adhesion molecule 1 (ICAM-1) levels above or equal to the median. There was a borderline association between increasing plasma angiopoietin 2 levels and KS. In multivariable modeling including plasma viral load, angiopoietin 2, and ICAM-1, plasma ICAM-1 levels above or equal to the median remained associated with clinical KS (odds ratio = 14.2, 95% confidence interval = 2.3-87.7). Circulating ICAM-1 levels should be evaluated as a potential biomarker for disease progression and treatment response among HIV-infected KS patients.

  19. Live-cell imaging reveals sequential oligomerization and local plasma membrane targeting of stromal interaction molecule 1 after Ca2+ store depletion

    PubMed Central

    Liou, Jen; Fivaz, Marc; Inoue, Takanari; Meyer, Tobias

    2007-01-01

    Stromal interaction molecule 1 (STIM1) has recently been identified by our group and others as an endoplasmic reticulum (ER) Ca2+ sensor that responds to ER Ca2+ store depletion and activates Ca2+ channels in the plasma membrane (PM). The molecular mechanism by which STIM1 transduces signals from the ER lumen to the PM is not yet understood. Here we developed a live-cell FRET approach and show that STIM1 forms oligomers within 5 s after Ca2+ store depletion. These oligomers rapidly dissociated when ER Ca2+ stores were refilled. We further show that STIM1 formed oligomers before its translocation within the ER network to ER–PM junctions. A mutant STIM1 lacking the C-terminal polybasic PM-targeting motif oligomerized after Ca2+ store depletion but failed to form puncta at ER–PM junctions. Using fluorescence recovery after photobleaching measurements to monitor STIM1 mobility, we show that STIM1 oligomers translocate on average only 2 μm to reach ER–PM junctions, arguing that STIM1 ER-to-PM signaling is a local process that is suitable for generating cytosolic Ca2+ gradients. Together, our live-cell measurements dissect the STIM1 ER-to-PM signaling relay into four sequential steps: (i) dissociation of Ca2+, (ii) rapid oligomerization, (iii) spatially restricted translocation to nearby ER–PM junctions, and (iv) activation of PM Ca2+ channels. PMID:17517596

  20. Expression, crystallization and preliminary X-ray diffraction analysis of the CMM2 region of the Arabidopsis thaliana Morpheus' molecule 1 protein.

    PubMed

    Petty, Tom J; Nishimura, Taisuke; Emamzadah, Soheila; Gabus, Caroline; Paszkowski, Jerzy; Halazonetis, Thanos D; Thore, Stéphane

    2010-08-01

    Of the known epigenetic control regulators found in plants, the Morpheus' molecule 1 (MOM1) protein is atypical in that the deletion of MOM1 does not affect the level of epigenetic marks controlling the transcriptional status of the genome. A short 197-amino-acid fragment of the MOM1 protein sequence can complement MOM1 deletion when coupled to a nuclear localization signal, suggesting that this region contains a functional domain that compensates for the loss of the full-length protein. Numerous constructs centred on the highly conserved MOM1 motif 2 (CMM2) present in these 197 residues have been generated and expressed in Escherichia coli. Following purification and crystallization screening, diamond-shaped single crystals were obtained that diffracted to approximately 3.2 A resolution. They belonged to the trigonal space group P3(1)21 (or P3(2)21), with unit-cell parameters a=85.64, c=292.74 A. Structure determination is ongoing.

  1. C-type lectin-like molecule-1 (CLL1)-targeted TRAIL augments the tumoricidal activity of granulocytes and potentiates therapeutic antibody-dependent cell-mediated cytotoxicity.

    PubMed

    Wiersma, Valerie R; de Bruyn, Marco; Shi, Ce; Gooden, Marloes J M; Wouters, Maartje C A; Samplonius, Douwe F; Hendriks, Djoke; Nijman, Hans W; Wei, Yunwei; Zhou, Jin; Helfrich, Wijnand; Bremer, Edwin

    2015-01-01

    The therapeutic effect of anti-cancer monoclonal antibodies stems from their capacity to opsonize targeted cancer cells with subsequent phagocytic removal, induction of antibody-dependent cell-mediated cytotoxicity (ADCC) or induction of complement-mediated cytotoxicity (CDC). The major immune effector cells involved in these processes are natural killer (NK) cells and granulocytes. The latter and most prevalent blood cell population contributes to phagocytosis, but is not effective in inducing ADCC. Here, we report that targeted delivery of the tumoricidal protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to granulocyte marker C-type lectin-like molecule-1 (CLL1), using fusion protein CLL1:TRAIL, equips granulocytes with high levels of TRAIL. Upon CLL1-selective binding of this fusion protein, granulocytes acquire additional TRAIL-mediated cytotoxic activity that, importantly, potentiates antibody-mediated cytotoxicity of clinically used therapeutic antibodies (e.g., rituximab, cetuximab). Thus, CLL1:TRAIL could be used as an adjuvant to optimize the clinical potential of anticancer antibody therapy by augmenting tumoricidal activity of granulocytes.

  2. Spectral investigation of the effect of anion on the stability of non covalent assemblies of 2,3,5,6,8,9,11,12-octahydro-1,4,7,10,13-benzopentaoxacyclopentadecine (benzo-15-crown-5) with sodium halides

    NASA Astrophysics Data System (ADS)

    Ghildiyal, Namrata; Pant, Geeta Joshi nee; Rawat, M. S. M.; Singh, Khushboo

    2017-01-01

    A series of complexes of 2,3,5,6,8,9,11,12-octahydro-1,4,7,10,13-benzopentaoxacyclopentadecine (benzo-15-crown-5) with sodium halides was synthesized in acetonitrile. The effect of anion on the stability and spectral properties of complexes of benzo-15-crown-5 with sodium halides was investigated. The synthesis of complexes of sodium fluoride and sodium chloride are reported for the first time. Chloroform was used as solvent to study the assembly in solution state by 1H and 13C NMR techniques. Single crystal diffraction studies on the easily crystallizable bromide complex confirmed 1:1 stoichiometry of the complex. IR and Raman studies provided valuable evidence for a water molecule shared between the crown encapsulated cation and the counter ion to give a solvent shared ion pair (SSIP). The fluorescence spectra of the complexes were obtained in chloroform by excitation at 270 nm to study the effect of complexation on the fluorescent properties of benzo-15-crown-5.

  3. A bioinformatics approach identifies signal transducer and activator of transcription-3 and checkpoint kinase 1 as upstream regulators of kidney injury molecule-1 after kidney injury.

    PubMed

    Ajay, Amrendra Kumar; Kim, Tae-Min; Ramirez-Gonzalez, Victoria; Park, Peter J; Frank, David A; Vaidya, Vishal S

    2014-01-01

    Kidney injury molecule-1 (KIM-1)/T cell Ig and mucin domain-containing protein-1 (TIM-1) is upregulated more than other proteins after AKI, and it is highly expressed in renal damage of various etiologies. In this capacity, KIM-1/TIM-1 acts as a phosphatidylserine receptor on the surface of injured proximal tubular epithelial cells, mediating phagocytosis of apoptotic cells, and it may also act as a costimulatory molecule for immune cells. Despite recognition of KIM-1 as an important therapeutic target for kidney disease, the regulators of KIM-1 transcription in the kidney remain unknown. Using a bioinformatics approach, we identified upstream regulators of KIM-1 after AKI. In response to tubular injury in rat and human kidneys or oxidant stress in human proximal tubular epithelial cells (HPTECs), KIM-1 expression increased significantly in a manner that corresponded temporally and regionally with increased phosphorylation of checkpoint kinase 1 (Chk1) and STAT3. Both ischemic and oxidant stress resulted in a dramatic increase in reactive oxygen species that phosphorylated and activated Chk1, which subsequently bound to STAT3, phosphorylating it at S727. Furthermore, STAT3 bound to the KIM-1 promoter after ischemic and oxidant stress, and pharmacological or genetic induction of STAT3 in HPTECs increased KIM-1 mRNA and protein levels. Conversely, inhibition of STAT3 using siRNAs or dominant negative mutants reduced KIM-1 expression in a kidney cancer cell line (769-P) that expresses high basal levels of KIM-1. These observations highlight Chk1 and STAT3 as critical upstream regulators of KIM-1 expression after AKI and may suggest novel approaches for therapeutic intervention.

  4. Serum Interleukin-18, Fetuin-A, Soluble Intercellular Adhesion Molecule-1, and Endothelin-1 in Ankylosing Spondylitis, Psoriatic Arthritis, and SAPHO Syndrome

    PubMed Central

    Przepiera-Będzak, Hanna; Fischer, Katarzyna; Brzosko, Marek

    2016-01-01

    To examine serum interleukin 18 (IL-18), fetuin-A, soluble intercellular adhesion molecule-1 (sICAM-1), and endothelin-1 (ET-1) levels in ankylosing spondylitis (AS), psoriatic arthritis (PsA), and Synovitis Acne Pustulosis Hyperostosis Osteitis syndrome (SAPHO). We studied 81 AS, 76 PsA, and 34 SAPHO patients. We measured serum IL-18, fetuin-A, sICAM-1, ET-1, IL-6, IL-23, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). IL-18 levels were higher in AS (p = 0.001), PsA (p = 0.0003), and SAPHO (p = 0.01) than in controls, and were positively correlated with CRP (p = 0.03), VEGF (p = 0.03), and total cholesterol (TC, p = 0.006) in AS and with IL-6 (p = 0.03) in PsA. Serum fetuin-A levels were lower in AS (p = 0.001) and PsA (p = 0.001) than in controls, and negatively correlated with C-reactive protein (CRP) in AS (p = 0.04) and SAPHO (p = 0.03). sICAM-1 positively correlated with CRP (p = 0.01), erythrocyte sedimentation rate (ESR, p = 0.01), and IL-6 (p = 0.008) in AS, and with IL-6 (p = 0.001) in SAPHO. Serum ET-1 levels were lower in AS (p = 0.0005) than in controls. ET-1 positively correlated with ESR (p = 0.04) and Disease Activity Score 28 (DAS28, p = 0.003) in PsA. In spondyloarthritis, markers of endothelial function correlated with disease activity and TC. PMID:27527149

  5. Serum Interleukin-18, Fetuin-A, Soluble Intercellular Adhesion Molecule-1, and Endothelin-1 in Ankylosing Spondylitis, Psoriatic Arthritis, and SAPHO Syndrome.

    PubMed

    Przepiera-Będzak, Hanna; Fischer, Katarzyna; Brzosko, Marek

    2016-08-03

    To examine serum interleukin 18 (IL-18), fetuin-A, soluble intercellular adhesion molecule-1 (sICAM-1), and endothelin-1 (ET-1) levels in ankylosing spondylitis (AS), psoriatic arthritis (PsA), and Synovitis Acne Pustulosis Hyperostosis Osteitis syndrome (SAPHO). We studied 81 AS, 76 PsA, and 34 SAPHO patients. We measured serum IL-18, fetuin-A, sICAM-1, ET-1, IL-6, IL-23, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). IL-18 levels were higher in AS (p = 0.001), PsA (p = 0.0003), and SAPHO (p = 0.01) than in controls, and were positively correlated with CRP (p = 0.03), VEGF (p = 0.03), and total cholesterol (TC, p = 0.006) in AS and with IL-6 (p = 0.03) in PsA. Serum fetuin-A levels were lower in AS (p = 0.001) and PsA (p = 0.001) than in controls, and negatively correlated with C-reactive protein (CRP) in AS (p = 0.04) and SAPHO (p = 0.03). sICAM-1 positively correlated with CRP (p = 0.01), erythrocyte sedimentation rate (ESR, p = 0.01), and IL-6 (p = 0.008) in AS, and with IL-6 (p = 0.001) in SAPHO. Serum ET-1 levels were lower in AS (p = 0.0005) than in controls. ET-1 positively correlated with ESR (p = 0.04) and Disease Activity Score 28 (DAS28, p = 0.003) in PsA. In spondyloarthritis, markers of endothelial function correlated with disease activity and TC.

  6. Maternal serum uric acid concentration is associated with the expression of tumour necrosis factor-α and intercellular adhesion molecule-1 in patients with preeclampsia.

    PubMed

    Zhao, J; Zheng, D-Y; Yang, J-M; Wang, M; Zhang, X-T; Sun, L; Yun, X-G

    2016-07-01

    We aimed to investigate whether there is a correlation between elevated serum uric acid (SUA) concentration and endothelial inflammatory response in women with preeclampsia (PE). On the basis of clinical and laboratory findings, patients were assigned to three groups: normal blood pressure (Control (Con)), gestational hypertension (GH) and PE (n=50 in each group). SUA concentration was measured by spectrophotometry, and serum tumour necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) levels were measured by enzyme-linked immunosorbent assay. Western blotting and immunohistochemical staining were also used to detect the changes in TNF-α and ICAM-1 expression in subcutaneous fat tissue. PE patients showed significantly higher systolic and diastolic blood pressures compared with Con and GH pregnant women (P=0.02 and P=0.02, respectively). The changes of body mass index (ΔBMI) before and after pregnancy and 24-h urine protein were significantly different among the three groups (P<0.001). Maternal SUA, TNF-α and soluble ICAM-1 (sICAM-1) levels were significantly increased in the patients with PE (P<0.05) compared with the other two groups. Scatterplot analysis revealed that elevated SUA concentration positively correlated with TNF-α and sICAM-1 in pregnant women. Moreover, vessels in subcutaneous fat tissues of preeclamptic patients showed intense TNF-α and ICAM-1 staining compared with Con and GH patients. The results support that, to a certain extent, elevated SUA concentration is significantly associated with inflammation of maternal systemic vasculature as indicated by increased TNF-α and ICAM-1 expression in women with PE.

  7. Simple modifications to Methimazole that enhance its inhibitory effect on Tumor Necrosis Factor-α-induced Vascular Cell Adhesion Molecule-1 expression by human endothelial cells

    PubMed Central

    Alapati, Anuja; Deosarkar, Sudhir P.; Lanier, Olivia L.; Qi, Chunyan; Carlson, Grady E.; Burdick, Monica M.; Schwartz, Frank L.; McCall, Kelly D.; Bergmeier, Stephen C.; Goetz, Douglas J.

    2015-01-01

    The expression of vascular cell adhesion molecule-1 (VCAM-1) on the vascular endothelium can be increased by pro-inflammatory cytokines [e.g. tumor necrosis factor – α (TNF-α)]. VCAM-1 contributes to leukocyte adhesion to, and emigration from, the vasculature which is a key aspect of pathological inflammation. As such, a promising therapeutic approach for pathological inflammation is to inhibit the expression of VCAM-1. Methimazole [3-methyl-1, 3 imidazole-2 thione (MMI)] is routinely used for the treatment of Graves’ disease and patients treated with MMI have decreased levels of circulating VCAM-1. In this study we used cultured human umbilical vein endothelial cells (HUVEC) to investigate the effect of MMI structural modifications on TNF-α induced VCAM-1 expression. We found that addition of a phenyl ring at the 4-nitrogen of MMI yields a compound that is significantly more potent than MMI at inhibiting 24 h TNF-α-induced VCAM-1 protein expression. Addition of a para methoxy to the appended phenyl group increases the inhibition while substitution of a thiazole ring for an imidazole ring in the phenyl derivatives yields no clear difference in inhibition. Addition of the phenyl ring to MMI appears to increase toxicity as does substitution of a thiazole ring for an imidazole ring in the phenyl MMI derivatives. Each of the compounds reduced TNF-α-induced VCAM-1 mRNA expression and had a functional inhibitory effect, i.e. each inhibited monocytic cell adhesion to 24 h TNF-α-activated HUVEC under fluid flow conditions. Combined, these studies provide important insights into the design of MMI-related anti-inflammatory compounds. PMID:25641748

  8. Kidney injury molecule-1 is up-regulated in renal epithelial cells in response to oxalate in vitro and in renal tissues in response to hyperoxaluria in vivo.

    PubMed

    Khandrika, Lakshmipathi; Koul, Sweaty; Meacham, Randall B; Koul, Hari K

    2012-01-01

    Oxalate is a metabolic end product excreted by the kidney. Mild increases in urinary oxalate are most commonly associated with Nephrolithiasis. Chronically high levels of urinary oxalate, as seen in patients with primary hyperoxaluria, are driving factor for recurrent renal stones, and ultimately lead to renal failure, calcification of soft tissue and premature death. In previous studies others and we have demonstrated that high levels of oxalate promote injury of renal epithelial cells. However, methods to monitor oxalate induced renal injury are limited. In the present study we evaluated changes in expression of Kidney Injury Molecule-1 (KIM-1) in response to oxalate in human renal cells (HK2 cells) in culture and in renal tissue and urine samples in hyperoxaluric animals which mimic in vitro and in vivo models of hyper-oxaluria. Results presented, herein demonstrate that oxalate exposure resulted in increased expression of KIM-1 m RNA as well as protein in HK2 cells. These effects were rapid and concentration dependent. Using in vivo models of hyperoxaluria we observed elevated expression of KIM-1 in renal tissues of hyperoxaluric rats as compared to normal controls. The increase in KIM-1 was both at protein and mRNA level, suggesting transcriptional activation of KIM-1 in response to oxalate exposure. Interestingly, in addition to increased KIM-1 expression, we observed increased levels of the ectodomain of KIM-1 in urine collected from hyperoxaluric rats. To the best of our knowledge our studies are the first direct demonstration of regulation of KIM-1 in response to oxalate exposure in renal epithelial cells in vitro and in vivo. Our results suggest that detection of KIM-1 over-expression and measurement of the ectodomain of KIM-1 in urine may hold promise as a marker to monitor oxalate nephrotoxicity in hyperoxaluria.

  9. Interaction between Endothelial Protein C Receptor and Intercellular Adhesion Molecule 1 to Mediate Binding of Plasmodium falciparum-Infected Erythrocytes to Endothelial Cells

    PubMed Central

    Avril, Marion; Bernabeu, Maria; Benjamin, Maxwell; Brazier, Andrew Jay

    2016-01-01

    ABSTRACT Intercellular adhesion molecule 1 (ICAM-1) and the endothelial protein C receptor (EPCR) are candidate receptors for the deadly complication cerebral malaria. However, it remains unclear if Plasmodium falciparum parasites with dual binding specificity are involved in cytoadhesion or different parasite subpopulations bind in brain microvessels. Here, we investigated this issue by studying different subtypes of ICAM-1-binding parasite lines. We show that two parasite lines expressing domain cassette 13 (DC13) of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family have dual binding specificity for EPCR and ICAM-1 and further mapped ICAM-1 binding to the first DBLβ domain following the PfEMP1 head structure in both proteins. As PfEMP1 head structures have diverged between group A (EPCR binders) and groups B and C (CD36 binders), we also investigated how ICAM-1-binding parasites with different coreceptor binding traits influence P. falciparum-infected erythrocyte binding to endothelial cells. Whereas levels of binding to tumor necrosis factor alpha (TNF-α)-stimulated endothelial cells from the lung and brain by all ICAM-1-binding parasite lines increased, group A (EPCR and ICAM-1) was less dependent than group B (CD36 and ICAM-1) on ICAM-1 upregulation. Furthermore, both group A DC13 parasite lines had higher binding levels to brain endothelial cells (a microvascular niche with limited CD36 expression). This study shows that ICAM-1 is a coreceptor for a subset of EPCR-binding parasites and provides the first evidence of how EPCR and ICAM-1 interact to mediate parasite binding to both resting and TNF-α-activated primary brain and lung endothelial cells. PMID:27406562

  10. Role of nuclear factor-kappa B in the regulation of intercellular adhesion molecule 1 after infection of human bronchial epithelial cells by Bordetella pertussis.

    PubMed

    Ishibashi, Yoshio; Nishikawa, Akemi

    2003-10-01

    Previous work has demonstrated that infection of human bronchial epithelial cells by Bordetella pertussis up-regulates intercellular adhesion molecule-1 (ICAM-1) gene and protein expression. It has also been shown that interaction of the Arg-Gly-Asp (RGD) site of filamentous hemagglutinin (FHA) with host cell very late antigen (VLA)-5 (alpha 5 beta 1 integrin) is required for the up-regulation of epithelial ICAM-1 expression, and that pertussis toxin (PT) impairs this response. We therefore examined the molecular mechanisms leading to B. pertussis-induced ICAM-1 up-regulation in BEAS-2B human bronchial epithelial cells. A colorimetric nuclear factor kappa B (NF-kappa B) activation assay demonstrated that NF-kappa B was activated in response to infection of these cells with B. pertussis. This activation occurred in an FHA(RGD)-dependent manner, and was blocked by an antibody against VLA-5, implying that binding of the RGD to VLA-5 integrin is involved in NF-kappa B activation. Western blot analysis revealed that the activation of NF-kappa B by B. pertussis was preceded by degradation of I kappa B alpha, a major cytoplasmic inhibitor of NF-kappa B. Pretreatment of the BEAS-2B cells with the NF-kappa B inhibitors pyrrolidine dithiocarbamate (PDTC), MG-132, and SN50 resulted in a marked decrease in B. pertussis-induced ICAM-1 expression, implying the involvement of NF-kappa B in ICAM-1 expression. Purified PT abrogated both NF-kappa B activation and I kappa B alpha degradation. These results suggest that ligation of VLA-5 integrin by FHA induces RGD-dependent NF-kappa B activation, thus leading to the up-regulation of epithelial ICAM-1 expression, and that a PT-sensitive G protein may be involved in this signaling pathway.

  11. Bordetella pertussis infection of human respiratory epithelial cells up-regulates intercellular adhesion molecule-1 expression: role of filamentous hemagglutinin and pertussis toxin.

    PubMed

    Ishibashi, Yoshio; Nishikawa, Akemi

    2002-09-01

    Adhesion molecules on respiratory epithelial cells play a critical role in inflammatory cell recruitment and accumulation at sites of inflammation. Bordetella pertussis colonizes the human respiratory tract by infecting epithelial cells, leading to an inflammatory response. In this study, the role of bacterial factors in the expression of intercellular adhesion molecule-1 (ICAM-1) on human respiratory epithelial cells was investigated in response to B. pertussis. Flow cytometry and real time RT-PCR analysis showed that BEAS-2B human bronchial epithelial cells expressed increased levels of ICAM-1 mRNA and surface protein in response to B. pertussis infection. Filamentous hemagglutinin (FHA) played a role in this response because of the impaired capability of a FHA-deficient isogenic strain. A mutant strain in which an Arg-Gly-Asp (RGD) site of FHA had been changed to Arg-Ala-Asp had diminished ability to up-regulate ICAM-1 expression. RGD sequence-associated up-regulation of ICAM-1 expression was also observed in primary normal human bronchial epithelial cells. Pretreatment of cells with integrin antagonists such as RGD-containing peptide and antibody against very late antigen-5 (VLA-5) inhibited the up-regulation of ICAM-1 expression, suggesting the participation of VLA-5 integrin in this response. Pertussis toxin (PT) prevented the up-regulation of ICAM-1 expression because a PT-deficient mutant strain induced higher levels of ICAM-1 mRNA and surface protein than the parental strain. Consistent with this, purified PT suppressed the up-regulation of epithelial ICAM-1 expression. These findings demonstrate that B. pertussis FHA up-regulates ICAM-1 expression on respiratory epithelial cells through interaction of its RGD site with host cell VLA-5 integrin, and that PT impairs this response.

  12. Effect of Hyperketonemia (Acetoacetate) on Nuclear Factor-κB and p38 Mitogen-Activated Protein Kinase Activation Mediated Intercellular Adhesion Molecule 1 Upregulation in Endothelial Cells

    PubMed Central

    Rains, Justin L.

    2015-01-01

    Abstract Background: Hyperketonemia is a pathological condition observed in patients with type 1 diabetes and ketosis-prone diabetes (KPD), which results in increased blood levels of acetoacetate (AA) and β-hydroxybutyrate (BHB). Frequent episodes of hyperketonemia are associated with a higher incidence of vascular disease. We examined the hypothesis that hyperketonemia activates the nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways that regulate intercellular adhesion molecule 1 (ICAM-1) expression in endothelial cells. Methods: Human umbilical vein endothelial cells (HUVECs) were cultured with AA (0–8 mM) or BHB (0–10 mM) for 0–24 hr. Western blotting was used to determine NF-κB activation in whole-cell lysates. ICAM-1 expression was measured using flow cytometry. Results: Results show a 2.4-fold increase in NF-κB activation in cells treated with 8 mM AA compared to the control. BHB had little or no effect on NF-κB activation. Pretreatment with a reactive oxygen species (ROS) inhibitor [N-acetyl-l-cysteine (NAC)] reduced NF-κB to near-control levels. The expression of AA-induced ICAM-1 was significantly reduced when cells were pretreated with either NAC or p38 MAPK inhibitor. Conclusions: These results suggest that NF-κB and p38 MAPK mediate upregulation of ICAM-1 expression in endothelial cells exposed to elevated levels of AA, which may contribute to the development of vascular disease in diabetes. PMID:25489974

  13. Effects of 17 β-estradiol on lipopolysacharride-induced intracellular adhesion molecule-1 mRNA expression and Ca2+ homeostasis alteration in human endothelial cells

    PubMed Central

    Thor, Der; Zhang, Rui; Anderson, Leigh; Bose, Diptiman; Dubé, Gregory P.; Rahimian, Roshanak

    2010-01-01

    Recent evidence showed that 17 β-estradiol (E2) decreased cytokine-induced expression of cell adhesion molecules (CAM). Changes in intracellular Ca2+ concentration ([Ca2+]i) has been shown to be associated with CAM expression in endothelial cells. Here, the effects of E2 (1 μM, 24 h) on the expression of intracellular adhesion molecule-1 (ICAM-1) and [Ca2+]i were investigated in a lipopolysaccharide (LPS) (100 ng/mL, 18 h)-stimulated human endothelial cell line, EA.hy926, using real-time PCR and spectrofluorometry, respectively. PCR analysis revealed a significant increase in ICAM-1 expression in calcium ionophore A23187 (1 nM)- or LPS-stimulated cells. Pretreatment of cells with E2 significantly inhibited LPS-induced ICAM-1 mRNA expression. [Ca2+]i was monitored in Fura-2 AM-loaded cells in the presence and absence of extracellular Ca2+ with thapsigargin (TG, 1 μM), a sarco/endoplasmic reticulum ATPase inhibitor or ATP (100 μM). The extent of TG- or ATP-induced [Ca2+]i increase was significantly higher in LPS-stimulated cells than in control cells. Pre-treatment of LPS-stimulated cells with E2 limited the Ca2+ response to the same level as in control cells. Furthermore, ICI 182,780, an estrogen receptor antagonist, attenuated the inhibitory actions of E2 on ICAM-1 mRNA expression and Ca2+ responses, suggesting that estrogen receptors mediate, at least in part, the effects of estrogen. These data suggest a potential underlying mechanism for the protective effect of E2 against atherosclerosis. PMID:20843480

  14. Intercellular adhesion molecule 1 is a sensitive and diagnostically useful immunohistochemical marker of papillary thyroid cancer (PTC) and of PTC-like nuclear alterations in Hashimoto's thyroiditis

    PubMed Central

    ZHANG, KE; GE, SHU-JIAN; LIN, XIAO-YAN; LV, BEI-BEI; CAO, ZHI-XIN; LI, JIA-MEI; XU, JIA-WEN; WANG, QIANG-XIU

    2016-01-01

    Intercellular adhesion molecule 1 (ICAM-1) is important in the progression of inflammatory responses. Recently, increased levels of ICAM-1 have been reported in a number of types of malignancy. The present study aimed to investigate ICAM-1 expression in papillary thyroid cancer (PTC) and in Hashimoto's thyroiditis (HT) with PTC-like nuclear alterations, and to assess the predictive value of ICAM-1 in thyroid lesions. ICAM-1 expression was retrospectively investigated in 132 consecutive cases of PTC, 72 cases of HT, 10 of follicular cancer, 15 of follicular adenoma, 16 of nodular goiter and 8 samples of normal thyroid tissue using immunohistochemical analyses, and in 42 PTC patients using western blotting. ICAM-1 expression was not detected in normal follicular cells, follicular lesions (adenoma and cancer) and benign nodular hyperplasia, but was frequently overexpressed in PTC cells. ICAM-1 overexpression was associated with extra-thyroidal invasion and lymph node metastasis; no association was found with age, gender, tumor size, multifocality, pathological stage, recurrence or distant metastasis. ICAM-1 expression in HT patients with PTC-like nuclear alterations was significantly higher than that in HT cases with non-PTC-like features. Compared with antibodies against cytokeratin 19, galectin-3 and Hector Battifora mesothelial-1, ICAM-1 was the most sensitive marker for the detection of PTC-like features in HT. These findings demonstrate that ICAM-1 expression is upregulated in PTC and in HT with PTC-like nuclear alterations. This feature may be an important factor in the progression of cancer of the thyroid gland. PMID:26998068

  15. Cyclic stretching of mesangial cells up-regulates intercellular adhesion molecule-1 and leukocyte adherence: a possible new mechanism for glomerulosclerosis.

    PubMed

    Riser, B L; Varani, J; Cortes, P; Yee, J; Dame, M; Sharba, A K

    2001-01-01

    Intraglomerular hypertension is a primary causal factor in the progressive glomerulosclerosis that characterizes diabetic nephropathy or severe renal ablation. However, inflammation of the glomerular mesangium also participates in at least the early phase of these diseases. In glomerulonephritis, where inflammation is thought to be the predominant causal factor, intraglomerular hypertension is also often present. Mesangial cells (MCs) are critical in orchestrating key functions of the glomerulus including extracellular matrix metabolism, cytokine production, and interaction with leukocytes. Because MCs are subject to increased stretching when intraglomerular hypertension is present, and in glomerulonephritis MC/leukocyte interactions seem to be mediated primarily via the up-regulation of intercellular adhesion molecule-1 (ICAM-1), we examine the possibility that cyclic stretching is a stimulus for increased MC ICAM-1 activity. We demonstrate that the normal low levels of MC ICAM-1 mRNA and protein are dramatically up-regulated by even short intervals of cyclic stretch. This effect is dose- and time-dependent, and requires little amplitude and a brief period of elongation for significant induction. Stretch-induced MC ICAM-1 also leads to a marked elevation in phagocytic leukocyte adherence. This stimulated adherence is equal or greater than that induced by the inflammatory cytokine tumor necrosis factor-alpha, whereas an additive effect occurs when both are applied in combination. Our results indicate that stretch-induced ICAM-1 may provide a direct link between hypertension and inflammation in the progression of injury and glomerulosclerosis in diabetes, renal ablation, and other forms of glomerulonephritis.

  16. Testosterone attenuates expression of vascular cell adhesion molecule-1 by conversion to estradiol by aromatase in endothelial cells: implications in atherosclerosis.

    PubMed

    Mukherjee, Tapan K; Dinh, Hillary; Chaudhuri, Gautam; Nathan, Lauren

    2002-03-19

    We previously reported that testosterone attenuated atherogenesis in LDLR(-/-) male mice, and that this effect of testosterone was most likely caused by its conversion to estradiol. Estradiol inhibits vascular cell adhesion molecule-1 (VCAM-1) expression, and expression of VCAM-1 is one of the early events in atherogenesis. We assessed the cellular mechanism(s) involved by which testosterone attenuates atherogenesis. We evaluated whether testosterone inhibited TNFalpha-induced VCAM-1 expression via its conversion to estradiol by the enzyme aromatase in human umbilical vein endothelial cells (HUVEC). Aromatase mRNA was dedected by reverse transcription-PCR in these cells. Testosterone (30 nM-1 microM) attenuated VCAM-1 mRNA expression in a concentration-dependent manner. The non aromatizable androgen, dihydrotestosterone, had no effect on VCAM-1 mRNA expression. Testosterone was less effective in attenuating VCAM-1 expression in the presence of anastrozole, an inhibitor of aromatase, indicating that testosterone inhibited VCAM-1 via conversion to estradiol. Estradiol also attenuated VCAM-1 mRNA expression, but this action was not abolished in the presence of anastrozole, indicating that anastrozole itself did not modulate VCAM-1 mRNA expression. The effect of testosterone on VCAM-1 mRNA expression was inhibited in the presence of the estrogen receptor antagonist, ICI-182780. Testosterone also attenuated TNFalpha-induced VCAM-1 protein expression, and this attenuation was abolished in the presence of anastrozole. In conclusion, testosterone inhibited VCAM-1 mRNA and protein expression in HUVEC by its conversion to estradiol via the enzyme aromatase present in the endothelial cells. Results from our study may help explain the mechanism by which testosterone may have beneficial effects on the cardiovascular system.

  17. Vitamin E supplementation reduces plasma vascular cell adhesion molecule-1 and von Willebrand factor levels and increases nitric oxide concentrations in hypercholesterolemic patients.

    PubMed

    Desideri, Giovambattista; Marinucci, Maria Contina; Tomassoni, Gianluca; Masci, Pier Giorgio; Santucci, Anna; Ferri, Claudio

    2002-06-01

    Up-regulation of vascular cell adhesion molecule-1 (VCAM-1) and reduced nitric oxide (NO) availability represent early characteristics of atherosclerosis. To evaluate whether the antioxidant vitamin E affected the circulating levels of soluble VCAM-1 (sVCAM-1) and the plasma metabolite of NO (nitrite+nitrate) in hypercholesterolemic patients, either vitamin E (either 400 IU or 800 IU/d for 8 wk) or placebo were randomly, double-blindly given to 36 hypercholesterolemic patients and 22 age- and sex-matched controls. At baseline hypercholesterolemic patients showed higher plasma sVCAM-1 (microg.liter(-1)) (591.2 +/- 132.5 vs. 505.0 +/- 65.6, P < 0.007) and lower NO metabolite (microM) levels (15.9 +/- 3.4 vs. 29.2 +/- 5.1, P < 0.0001) than controls. In hypercholesterolemic patients, 8 wk vitamin E (but not placebo) treatment significantly decreased circulating sVCAM-1 levels (400 IU: -148.9 +/- 84.6, P < 0.009; 800 IU: -204.0 +/- 75.7, P < 0.0001; placebo: -4.7 +/- 22.6, NS), whereas it increased NO metabolite concentrations (400 IU: +4.0 +/- 1.7, P < 0.02; 800 IU: +5.5 +/- 0.8, P < 0.0001; placebo: +0.1 +/- 1.1, NS) without affecting circulating low- density lipoprotein levels. Changes in both plasma sVCAM-1 and NO metabolite levels showed a trend to significantly correlate (r = -0.515, P = 0.010; and r = 0.435, P = 0.034, respectively) with changes in vitamin E concentrations induced by vitamin E supplementation. In conclusion, isolated hypercholesterolemia both increased circulating sVCAM-1 and reduced NO metabolite concentrations. Vitamin E supplementation counteracts these alterations, thus representing a potential tool for endothelial protection in hypercholesterolemic patients.

  18. An anti-platelet-endothelial cell adhesion molecule-1 antibody inhibits leukocyte extravasation from mesenteric microvessels in vivo by blocking the passage through the basement membrane

    PubMed Central

    1996-01-01

    Platelet-endothelial cell adhesion molecule-1 (PECAM-1, CD31) plays an active role in the process of leukocyte migration through cultured endothelial cells in vitro and anti-PECAM-1 antibodies (Abs) inhibit accumulation of leukocytes into sites of inflammation in vivo. Despite the latter, it is still not clear at which stage of leukocyte emigration in vivo PECAM-1 is involved. To address this point directly, we studied the effect of an anti-PECAM-1 Ab, recognizing rat PECAM-1, on leukocyte responses within rat mesenteric microvessels using intravital microscopy. In mesenteric preparations activated by interleukin (IL)-1 beta, the anti-PECAM-1 Ab had no significant effect on the rolling or adhesion of leukocytes, but inhibited their migration into the surrounding extravascular tissue in a dose-dependent manner. Although in some vessel segments these leukocytes had come to a halt within the vascular lumen, often the leukocytes appeared to be trapped within the vessel wall. Analysis of these sections by electron microscopy revealed that the leukocytes had passed through endothelial cell junctions but not the basement membrane. In contrast to the effect of the Ab in mesenteric preparations treated with IL-1 beta, leukocyte extravasation induced by topical or intraperitoneal administration of the chemotactic peptide formyl-methionyl-leucyl-phenylalanine was not inhibited by the anti-PECAM-1 Ab. These results directly demonstrate a role for PECAM-1 in leukocyte extravasation in vivo and indicate that this involvement is selective for leukocyte extravasation elicited by certain inflammatory mediators. Further, our findings provide the first in vivo indication that PECAM-1 may have an important role in triggering the passage of leukocytes through the perivascular basement membrane. PMID:8691137

  19. Simple modifications to methimazole that enhance its inhibitory effect on tumor necrosis factor-α-induced vascular cell adhesion molecule-1 expression by human endothelial cells.

    PubMed

    Alapati, Anuja; Deosarkar, Sudhir P; Lanier, Olivia L; Qi, Chunyan; Carlson, Grady E; Burdick, Monica M; Schwartz, Frank L; McCall, Kelly D; Bergmeier, Stephen C; Goetz, Douglas J

    2015-03-15

    The expression of vascular cell adhesion molecule-1 (VCAM-1) on the vascular endothelium can be increased by pro-inflammatory cytokines [e.g. tumor necrosis factor-α (TNF-α)]. VCAM-1 contributes to leukocyte adhesion to, and emigration from, the vasculature which is a key aspect of pathological inflammation. As such, a promising therapeutic approach for pathological inflammation is to inhibit the expression of VCAM-1. Methimazole [3-methyl-1, 3 imidazole-2 thione (MMI)] is routinely used for the treatment of Graves׳ disease and patients treated with MMI have decreased levels of circulating VCAM-1. In this study we used cultured human umbilical vein endothelial cells (HUVEC) to investigate the effect of MMI structural modifications on TNF-α induced VCAM-1 expression. We found that addition of a phenyl ring at the 4-nitrogen of MMI yields a compound that is significantly more potent than MMI at inhibiting 24h TNF-α-induced VCAM-1 protein expression. Addition of a para methoxy to the appended phenyl group increases the inhibition while substitution of a thiazole ring for an imidazole ring in the phenyl derivatives yields no clear difference in inhibition. Addition of the phenyl ring to MMI appears to increase toxicity as does substitution of a thiazole ring for an imidazole ring in the phenyl MMI derivatives. Each of the compounds reduced TNF-α-induced VCAM-1 mRNA expression and had a functional inhibitory effect, i.e. each inhibited monocytic cell adhesion to 24h TNF-α-activated HUVEC under fluid flow conditions. Combined, these studies provide important insights into the design of MMI-related anti-inflammatory compounds.

  20. Soluble intracellular adhesion molecule-1 secreted by human umbilical cord blood-derived mesenchymal stem cell reduces amyloid-β plaques.

    PubMed

    Kim, J-Y; Kim, D H; Kim, J H; Lee, D; Jeon, H B; Kwon, S-J; Kim, S M; Yoo, Y J; Lee, E H; Choi, S J; Seo, S W; Lee, J I; Na, D L; Yang, Y S; Oh, W; Chang, J W

    2012-04-01

    Presently, co-culture of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) with BV2 microglia under amyloid-β42 (Aβ42) exposure induced a reduction of Aβ42 in the medium as well as an overexpression of the Aβ-degrading enzyme neprilysin (NEP) in microglia. Cytokine array examinations of co-cultured media revealed elevated release of soluble intracellular adhesion molecule-1 (sICAM-1) from hUCB-MSCs. Administration of human recombinant ICAM-1 in BV2 cells and wild-type mice brains induced NEP expression in time- and dose-dependent manners. In co-culturing with BV2 cells under Aβ42 exposure, knockdown of ICAM-1 expression on hUCB-MSCs by small interfering RNA (siRNA) abolished the induction of NEP in BV2 cells as well as reduction of added Aβ42 in the co-cultured media. By contrast, siRNA-mediated inhibition of the sICAM-1 receptor, lymphocyte function-associated antigen-1 (LFA-1), on BV2 cells reduced NEP expression by ICAM-1 exposure. When hUCB-MSCs were transplanted into the hippocampus of a 10-month-old transgenic mouse model of Alzheimer's disease for 10, 20, or 40 days, NEP expression was increased in the mice brains. Moreover, Aβ42 plaques in the hippocampus and other regions were decreased by active migration of hUCB-MSCs toward Aβ deposits. These data suggest that hUCB-MSC-derived sICAM-1 decreases Aβ plaques by inducing NEP expression in microglia through the sICAM-1/LFA-1 signaling pathway.

  1. Vascular and extravascular immunoreactivity for Intercellular Adhesion Molecule 1 in the orbitofrontal cortex of subjects with major depression: age-dependent changes

    PubMed Central

    Miguel-Hidalgo, Jose Javier; Overholser, James C.; Jurjus, George J.; Meltzer, Herbert Y.; Dieter, Lesa; Konick, Lisa; Stockmeier, Craig A.; Rajkowska, Grazyna

    2011-01-01

    Background Vascular and immune alterations in the prefrontal cortex may contribute to major depression in elderly subjects. Intercellular adhesion molecule-1 (ICAM-1), major inflammatory mediator in vessels and astrocytes, could be altered in geriatric depression, but little is known about its age-dependent expression in subjects with depression and its relationship to astrocytes identified by the marker glial fibrillary acidic protein (GFAP), found to be reduced in depression. Methods We measured the percentage of gray matter area fraction covered by ICAM-1 immunoreactivity in blood vessels and in extravascular accumulations of ICAM-1 immunoreactivity in 19 non-psychiatric comparison subjects and 18 subjects with major depression, all characterized by postmortem psychological diagnosis. Association of extravascular ICAM-1 to GFAP-positive astrocytes was investigated by double-labeling immunofluorescence. Results Vascular and extravascular fractions of ICAM-1 immunoreactivity were lower in subjects with MDD than in non-psychiatric comparison subjects. Non-psychiatric comparison subjects older than 60 experienced dramatic increase in extravascular ICAM-1 immunoreactivity, but this increase was attenuated in elderly subjects with MDD, particularly in those dying by suicide. Most extracellular ICAM-1 immunoreactivity was coextensive with GFAP-immunoreactive astrocytes in both groups. Limitations Heterogeneity in type and dosage of antidepressant medication. Difficulty in determining the exact onset of depression in subjects older than 60 at the time of death. Routine cerebrovascular pathological screening may miss subtle subcellular and molecular changes. Conclusions There is significant attenuation of extravascular and vascular ICAM-1 immunoreactivity in elderly subjects with major depression suggesting an astrocyte-associated alteration in immune function in the aging orbitofrontal cortex of subjects with MDD. PMID:21536333

  2. The Serum Changes of Neuron-Specific Enolase and Intercellular Adhesion Molecule-1 in Patients With Diffuse Axonal Injury Following Progesterone Administration: A Randomized Clinical Trial

    PubMed Central

    Shahrokhi, Nader; Soltani, Zahra; Khaksari, Mohammad; Karamouzian, Saeid; Mofid, Behshad; Asadikaram, Gholamreza

    2016-01-01

    Background Improvement of neurologic outcome in progesterone-administered patients with diffuse axonal injury (DAI) has been found in a recent study. Also, there has been interest in the importance of serum parameters as predictors of outcome in traumatic brain injury. Objectives The aim of this study was to examine the effect of progesterone administration on serum levels of neuron-specific enolase (NSE), and intercellular adhesion molecule-1 (ICAM-1) in clinical DAI. Patients and Methods In this study, the serum levels of ICAM-1 and NSE of 32 male DAI patients (18 - 60 years of age, a Glasgow coma scale of 12 or less, and admitted within 4 hours after injury) who were randomized for a controlled phase II trial of progesterone were analyzed. The analysis was performed between the control and progesterone groups at admission time, and 24 hours and six days after DAI, respectively. Results A reduction in the serum level of ICAM-1 was noticed in the progesterone group 24 hours after the injury (P < 0.05). There was no significant difference in the serum level of NSE between the study groups during evaluation. At 24 hours after the injury, the level of ICAM-1 in the control group was higher than that at admission time (P < 0.05). The lowest level of NSE in the two groups was seen six days after DAI (P < 0.01). Conclusions In summary, progesterone administration reduced serum ICAM-1, and whereby may attenuate blood brain barrier disruption, the latter needs further investigation for confirmation. PMID:27800469

  3. Urinary kidney injury molecule-1 as an early diagnostic biomarker of obstructive acute kidney injury and development of a rapid detection method

    PubMed Central

    Jin, Yingli; Shao, Xiaona; Sun, Bo; Miao, Chunsheng; Li, Zhengqiang; Shi, Yan

    2017-01-01

    The aim of the present study was to investigate whether urinary kidney injury molecule-1 (KIM-1) presents a suitable early diagnostic biomarker of obstructive nephropathy-induced acute kidney injury (AKI), and to develop a rapid detection method for urinary KIM-1. Obstructive AKI was induced in an experimental rat model by a unilateral ureteral obstruction (UUO) operation. Macro- and micromorphological kidney alterations were determined by visual observation and hematoxylin and eosin (HE) staining, respectively. Kidney functions were evaluated by detecting urea nitrogen and creatinine levels in rat urine and blood. Urinary KIM-1 levels were measured using an enzyme-linked immunosorbent assay, and the protein expression levels of KIM-1, α-smooth muscle actin (α-SMA) and vimentin in kidney tissues were detected using immunohistochemical assays. In order to measure KIM-1 levels, colloidal gold immunochromatographic strips were developed based on the colloidal gold immunochromatographic assay. The results indicated that KIM-1 levels were significantly higher in the UUO group when compared with the Sham group. KIM-1 levels in the urine and kidney tissues exhibited a time-dependent increase, together with increasing obstructive AKI in the UUO group. In addition, KIM-1 levels were demonstrated to be a more sensitive biomarker of early obstructive AKI, when compared with α-SMA and vimentin. A colloidal gold-based immunochromatographic strip was developed, whereby the detection of urinary KIM-1 could be completed within 5–10 min. In conclusion, results of the present study demonstrated that urinary KIM-1 may be a valuable biomarker for the early diagnosis of obstructive AKI, and the use of a colloidal gold immunochromatographic strip may be a promising method for the rapid detection of urinary KIM-1. PMID:28075469

  4. 5,7-Dihydroxy-3,4,6-trimethoxyflavone inhibits intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 via the Akt and nuclear factor-κB-dependent pathway, leading to suppression of adhesion of monocytes and eosinophils to bronchial epithelial cells.

    PubMed

    Jung, Jireh; Ko, Su H; Yoo, Do Y; Lee, Jin Y; Kim, Yeong-Jeon; Choi, Seul M; Kang, Kyung K; Yoon, Ho J; Kim, Hyeyoung; Youn, Jeehee; Kim, Jung M

    2012-09-01

    5,7-Dihydroxy-3',4',6'-trimethoxyflavone (eupatilin), the active pharmacological ingredient from Artemisia asiatica Nakai (Asteraceae), is reported to have a variety of anti-inflammatory properties in intestinal epithelial cells. However, little information is known about the molecular mechanism of eupatilin-induced attenuation of bronchial epithelial inflammation. This study investigates the role of eupatilin in the adhesion of inflammatory cells such as monocytes and eosinophils to bronchial epithelial cells. Stimulation of a human bronchial epithelial cell line (BEAS-2B) with tumour necrosis factor-α (TNF-α) increased the expression of surface adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), in which eupatilin significantly inhibited the expression of those adhesion molecules in a dose-dependent manner. Eupatilin suppressed the TNF-α-induced activation of IκBα and nuclear factor-κB (NF-κB) signals in BEAS-2B cells. The IκB kinase (IKK) activation was also significantly reduced in eupatilin-pre-treated BEAS-2B and primary normal human bronchial epithelial (NHBE) cells. However, eupatilin did not influence AP-1 activity in TNF-α-stimulated cells. Suppression of NF-κB signalling induced by eupatilin resulted in the inhibition of the expression of adhesion molecules and the adhesion of monocytes and eosinophils to BEAS-2B cells. Furthermore, eupatilin suppressed the phosphorylation of Akt in TNF-α-stimulated BEAS-2B and NHBE cells, leading to down-regulation of NF-κB activation and adhesion molecule expression and finally to suppression of the inflammatory cell adhesion to epithelial cells. These results suggest that eupatilin can inhibit the adhesion of inflammatory cells to bronchial epithelial cells via a signalling pathway, including activation of Akt and NF-κB, as well as expression of adhesion molecules.

  5. 5,7-Dihydroxy-3,4,6-trimethoxyflavone inhibits intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 via the Akt and nuclear factor-κB-dependent pathway, leading to suppression of adhesion of monocytes and eosinophils to bronchial epithelial cells

    PubMed Central

    Jung, Jireh; Ko, Su H; Yoo, Do Y; Lee, Jin Y; Kim, Yeong-Jeon; Choi, Seul M; Kang, Kyung K; Yoon, Ho J; Kim, Hyeyoung; Youn, Jeehee; Kim, Jung M

    2012-01-01

    5,7-Dihydroxy-3′,4′,6′-trimethoxyflavone (eupatilin), the active pharmacological ingredient from Artemisia asiatica Nakai (Asteraceae), is reported to have a variety of anti-inflammatory properties in intestinal epithelial cells. However, little information is known about the molecular mechanism of eupatilin-induced attenuation of bronchial epithelial inflammation. This study investigates the role of eupatilin in the adhesion of inflammatory cells such as monocytes and eosinophils to bronchial epithelial cells. Stimulation of a human bronchial epithelial cell line (BEAS-2B) with tumour necrosis factor-α (TNF-α) increased the expression of surface adhesion molecules, including intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), in which eupatilin significantly inhibited the expression of those adhesion molecules in a dose-dependent manner. Eupatilin suppressed the TNF-α-induced activation of IκBα and nuclear factor-κB (NF-κB) signals in BEAS-2B cells. The IκB kinase (IKK) activation was also significantly reduced in eupatilin-pre-treated BEAS-2B and primary normal human bronchial epithelial (NHBE) cells. However, eupatilin did not influence AP-1 activity in TNF-α-stimulated cells. Suppression of NF-κB signalling induced by eupatilin resulted in the inhibition of the expression of adhesion molecules and the adhesion of monocytes and eosinophils to BEAS-2B cells. Furthermore, eupatilin suppressed the phosphorylation of Akt in TNF-α-stimulated BEAS-2B and NHBE cells, leading to down-regulation of NF-κB activation and adhesion molecule expression and finally to suppression of the inflammatory cell adhesion to epithelial cells. These results suggest that eupatilin can inhibit the adhesion of inflammatory cells to bronchial epithelial cells via a signalling pathway, including activation of Akt and NF-κB, as well as expression of adhesion molecules. PMID:22862554

  6. Molecule 1,5-C10H6(SO2Cl)2 as prototype of conformational properties of naphthalene sulfonyl derivatives

    NASA Astrophysics Data System (ADS)

    Petrov, Vjacheslav M.; Giricheva, Nina I.; Ivanov, Sergey N.; Petrova, Valentina N.; Girichev, Georgiy V.

    2017-03-01

    Conformational composition of the vapor (T = 413(5) K) and the conformer structures of 1,5-naphthalenedisulfonylchloride (1,5-NaphDSC) have been studied by a combined gas-phase electron diffraction and mass spectrometry (GED/MS) method complemented by quantum chemical calculations. According to quantum chemical calculations at DFT/B3LYP/cc-pVTZ and MP2/cc-pVTZ theory levels, the molecule 1,5-NaphDSC possesses four conformers differing mutual orientation of the two SO2Cl groups. GED data clearly indicate that only two conformers, whose structures are characterized by deviation of two Ssbnd Cl bonds from perpendicular position relative to the plane of the naphthalene skeleton (syn-symmetry C2 and anti-symmetry Ci), are present in vapor at 413 K. The following geometrical parameters of these conformers were obtained from the experiment (Å and degrees; uncertainties are in parentheses): rh1(Csbnd H) = 1.098(9), rh1(Csbnd C) = 1.405(3), rh1(Csbnd S) = 1.781(4), rh1(Ssbnd O) = 1.426(3), rh1(Ssbnd Cl) = 2.056(4), ∠Csbnd CSsbnd C = 122.9(1), ∠CSsbnd Ssbnd Cl = 101.8(6); C9sbnd C1sbnd Ssbnd Cl = 71.2(12), C10sbnd C5sbnd Ssbnd Cl = 71.2(12)-syn conformer; C9sbnd C1sbnd Ssbnd Cl = 71.2(12), C10sbnd C5sbnd Ssbnd Cl = -71.2(12) -anti-conformer. The presence of C9Hn+ ions in the mass spectra of naphthalenesulfonyl chlorides, which are absent in the mass spectrum of naphthalene, may be attributed to the weakening of two Csbnd C bonds adjacent to the substituent of the naphthalene skeleton. This reflects in the geometric parameters of 1,5-NaphDSC. The barriers to internal rotation of sulfonyl chloride groups were calculated. It is shown that the low-energy syn- and anti-conformers are structurally rigid, in contrast to high-energy conformers with one or two Ssbnd Cl bonds, lying in the plane of the naphthalene skeleton. The dependence of C1sbnd C2, Csbnd S, Ssbnd Cl bond lengths from SO2Cl groups orientation relative to naphthalene skeleton is discussed in terms of NBO

  7. Effects of nitrogen dioxide on the expression of intercellular adhesion molecule-1, neutrophil adhesion, and cytotoxicity: studies in human bronchial epithelial cells.

    PubMed

    Ayyagari, Vijayalakshmi N; Januszkiewicz, Adolph; Nath, Jayasree

    2007-02-01

    Nitrogen Dioxide (NO2) is a product of high-temperature combustion and an environmental oxidant of concern. We have recently reported that early changes in NO2-exposed human bronchial epithelial cells are causally linked to increased generation of proinflammatory mediators, such as nitric oxide/nitrite and cytokines like interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and IL-8. The objective of the present in vitro study was to further delineate the cellular mechanisms of NO2-mediated toxicity, and to define the nature of cell death that ensues upon exposure of normal human bronchial epithelial (NHBE) cells to a brief high dose of NO2. Our results demonstrate that the NHBE cells undergo apoptotic cell death during the early post-NO2 period, but this is independent of any significant increase in caspase-3 activity. However, necrotic cell death was more prevalent at later time intervals. Interestingly, an increased expression of HO-1, a redox-sensitive stress protein, was observed in NO2-exposed NHBE cells at 24 h. Since neutrophils (PMNs) play an active role in acute lung inflammation and resultant oxidative injury, we also investigated changes in human PMN-NHBE cell interactions. As compared to normal cells, increased adhesion of PMNs to NO2-exposed cells was observed, which resulted in an increased NHBE cell death. The latter was also increased in the presence of IL-8 and TNF-alpha + interferon (IFN)-gamma, which correlated with upregulation of intercellular adhesion molecule-1 (ICAM-1). Our results confirmed an involvement of nitric oxide (NO) in NO2-induced cytotoxicity. By using NO synthase inhibitors such as L-NAME and 3-aminoguanidine (AG), a significant decrease in cell death, PMN adhesion, and ICAM-1 expression was observed. These findings indicate a role for the L-arginine/NO synthase pathway in the observed NO2-mediated toxicity in NHBE cells. Therapeutic strategies aimed at controlling excess generation of NO and/or inflammatory cytokines may

  8. Exosomes from iPSCs Delivering siRNA Attenuate Intracellular Adhesion Molecule-1 Expression and Neutrophils Adhesion in Pulmonary Microvascular Endothelial Cells.

    PubMed

    Ju, Zhihai; Ma, Jinhui; Wang, Chen; Yu, Jie; Qiao, Yeru; Hei, Feilong

    2017-04-01

    The pro-inflammatory activation of pulmonary microvascular endothelial cells resulting in continuous expression of cellular adhesion molecules, and subsequently recruiting primed neutrophils to form a firm neutrophils-endothelium (PMN-EC) adhesion, has been examined and found to play a vital role in acute lung injury (ALI). RNA interference (RNAi) is a cellular process through harnessing a natural pathway silencing target gene based on recognition and subsequent degradation of specific mRNA sequences. It opens a promising approach for precision medicine. However, this application was hampered by many obstacles, such as immunogenicity, instability, toxicity problems, and difficulty in across the biological membrane. In this study, we reprogrammed urine exfoliated renal epithelial cells into human induced pluripotent stem cells (huiPSCs) and purified the exosomes (Exo) from huiPSCs as RNAi delivery system. Through choosing the episomal system to deliver transcription factors, we obtained a non-integrating huiPSCs. Experiments in both vitro and vivo demonstrated that these huiPSCs possess the pluripotent properties. The exosomes of huiPSCs isolated by differential centrifugation were visualized by transmission electron microscopy (TEM) showing a typical exosomal appearance with an average diameter of 122 nm. Immunoblotting confirmed the presence of the typical exosomal markers, including CD63, TSG 101, and Alix. Co-cultured PKH26-labeled exosomes with human primary pulmonary microvascular endothelial cells (HMVECs) confirmed that they could be internalized by recipient cells at a time-dependent manner. Then, electroporation was used to introduce siRNA against intercellular adhesion molecule-1 (ICAM-1) into exosomes to form an Exo/siRNA compound. The Exo/siRNA compound efficiently delivered the target siRNA into HMVECs causing selective gene silencing, inhibiting the ICAM-1 protein expression, and PMN-EC adhesion induced by lipopolysaccharide (LPS). These data suggest

  9. Ultraviolet radiation can either suppress or induce expression of intercellular adhesion molecule 1 (ICAM-1) on the surface of cultured human keratinocytes

    SciTech Connect

    Norris, D.A.; Lyons, M.B.; Middleton, M.H.; Yohn, J.J.; Kashihara-Sawami, M. )

    1990-08-01

    Interactions of the ligand/receptor pair LFA-1(CD11a/CD18) and ICAM-1(CD54) initiate and control the cell-cell interactions of leukocytes and interactions of leukocytes with parenchymal cells in all phases of the immune response. Induction of the intercellular adhesion molecule 1 (ICAM-1) on the surface of epidermal keratinocytes has been proposed as an important regulator of contact-dependent aspects of cutaneous inflammation. Ultraviolet radiation (UVR) also modifies cutaneous inflammation, producing both up- and down-regulation of contact hypersensitivity. We have found that UVR has a biphasic effect on the induction of keratinocyte CD54. Using immunofluorescence and FACS techniques to quantitate cell-surface CD54 staining, we have shown that UVR significantly (p less than 0.01) inhibits keratinocyte CD54 induction by gamma interferon 24 h after irradiation. However, at 48, 72, and 96 h after UVR, CD54 expression is significantly induced to levels even greater than are induced by gamma interferon (20 U/ml). In addition, at 48, 72, or 96 h following UVR (30-100 mJ/cm2), the gamma-interferon-induced CD54 expression on human keratinocytes is also strongly (p less than 0.05 to p less than 0.001) enhanced. In this cell-culture system, gamma interferon and TNF-alpha are both strong CD54 inducers and are synergistic, but GM-CSF, TFG-beta, and IL-1 have no direct CD54-inducing effects. Thus the effects of UVR on CD54 induction are biphasic, producing inhibition at 24 h and induction at 48, 72, and 96 h. This effect on CD54 may contribute to the biphasic effects of UVR on delayed hypersensitivity in vivo. The early inhibition of ICAM-1 by UVR may also contribute to the therapeutic effects of UVR. We also speculate that the late induction of ICAM-1 by UVR might be an important step in the induction of photosensitive diseases such as lupus erythematosus.

  10. Circulating Concentrations of Monocyte Chemoattractant Protein-1, Plasminogen Activator Inhibitor-1, and Soluble Leukocyte Adhesion Molecule-1 in Overweight/Obese Men and Women Consuming Fructose- or Glucose-Sweetened Beverages for 10 Weeks

    PubMed Central

    Cox, Chad L.; Stanhope, Kimber L.; Schwarz, Jean Marc; Graham, James L.; Hatcher, Bonnie; Griffen, Steven C.; Bremer, Andrew A.; Berglund, Lars; McGahan, John P.; Keim, Nancy L.

    2011-01-01

    Context: Results from animal studies suggest that consumption of large amounts of fructose can promote inflammation and impair fibrinolysis. Data describing the effects of fructose consumption on circulating levels of proinflammatory and prothrombotic markers in humans are unavailable. Objective: Our objective was to determine the effects of 10 wk of dietary fructose or glucose consumption on plasma concentrations of monocyte chemoattractant protein-1 (MCP-1), plasminogen activator inhibitor-1 (PAI-1), E-selectin, intercellular adhesion molecule-1, C-reactive protein, and IL-6. Design and Setting: This was a parallel-arm study with two inpatient phases (2 wk baseline, final 2 wk intervention), conducted in a clinical research facility, and an outpatient phase (8 wk) during which subjects resided at home. Participants: Participants were older (40–72 yr), overweight/obese (body mass index = 25–35 kg/m2) men (n = 16) and women (n = 15). Interventions: Participants consumed glucose- or fructose-sweetened beverages providing 25% of energy requirements for 10 wk. Blood samples were collected at baseline and during the 10th week of intervention. Main Outcome Measures: Fasting concentrations of MCP-1 (P = 0.009), PAI-1 (P = 0.002), and E-selectin (P = 0.048) as well as postprandial concentrations of PAI-1 (P < 0.0001) increased in subjects consuming fructose but not in those consuming glucose. Fasting levels of C-reactive protein, IL-6, and intercellular adhesion molecule-1 were not changed in either group. Conclusions: Consumption of fructose for 10 wk leads to increases of MCP-1, PAI-1, and E-selectin. These findings suggest the possibility that fructose may contribute to the development of the metabolic syndrome via effects on proinflammatory and prothrombotic mediators. PMID:21956423

  11. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., Poecile gambeli CHUCK-WILL'S-WIDOW, Caprimulgus carolinensis CONDOR, California, Gymnogyps californianus... Vulture Cathartes aura, Turkey Vulture Gymnogyps californianus, California Condor Family...

  12. 15 CFR 10.13 - Withdrawal of a published standard.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Standards & Technology at any time. Such action will be taken if, after consultation with the Standing... determines that the requested standard or standards shall be withdrawn, the stay will remain in effect, if an... the Federal Register and such withdrawal will take effect 60 days from the date the withdrawal...

  13. US EPA, Pesticide Product Label, , 10/13/1993

    EPA Pesticide Factsheets

    2011-04-21

    ... Pr.I ... ", c;l.tIo'IiAI aAIl '_ .. ill .... M· far ... 1 I' ,1,.,.F IIF.II IIi t. IIIIhiA" If III..... refltl v. laMa".iMI.11 ,1.thiAI aA-' 'A'.'" 110" i",,,,lIi.,... ttI:l lat, IAII U'I'''' wet", •• , ...

  14. 15 CFR 10.13 - Withdrawal of a published standard.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the industry; inconsistent with law or established public policy; not in the public interest; or... Committee as provided in paragraph (a)(1) of this section and after public notice, the Director determines... substantial public impact, that it does not duplicate a standard published by a private...

  15. Legislative Update, June 2010. Report 10-13

    ERIC Educational Resources Information Center

    Blair, Julia

    2010-01-01

    This update contains analyses of legislation being tracked by California Postsecondary Education Commission (CPEC) staff. It has updated positions on bills as adopted in the Commission meeting on June 8. A matrix of bills tracked by CPEC staff is included.

  16. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., Milvus migrans Hook-billed, Chondrohierax uncinatus Mississippi, Ictinia mississippiensis Snail... Elanoides forficatus, Swallow-tailed Kite Elanus leucurus, White-tailed Kite Rostrhamus sociabilis,...

  17. Small GTPase Rho signaling is involved in {beta}1 integrin-mediated up-regulation of intercellular adhesion molecule 1 and receptor activator of nuclear factor {kappa}B ligand on osteoblasts and osteoclast maturation

    SciTech Connect

    Hirai, Fumihiko; Nakayamada, Shingo; Okada, Yosuke; Saito, Kazuyoshi; Kurose, Hitoshi; Mogami, Akira; Tanaka, Yoshiya . E-mail: tanaka@med.uoeh-u.ac.jp

    2007-04-27

    We assessed the characteristics of human osteoblasts, focusing on small GTPase Rho signaling. {beta}1 Integrin were highly expressed on osteoblasts. Engagement of {beta}1 integrins by type I collagen augmented expression of intercellular adhesion molecule 1 (ICAM-1) and receptor activator of nuclear factor {kappa}B ligand (RANKL) on osteoblasts. Rho was activated by {beta}1 stimulation in osteoblasts. {beta}1 Integrin-induced up-regulation of ICAM-1 and RANKL was inhibited by transfection with adenoviruses encoding C3 transferase or pretreated with Y-27632, specific Rho and Rho-kinase inhibitors. Engagement of {beta}1 integrin on osteoblasts induced formation of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells (MNC) in a coculture system of osteoblasts and peripheral monocytes, but this action was completely abrogated by transfection of C3 transferase. Our results indicate the direct involvement of Rho-mediated signaling in {beta}1 integrin-induced up-regulation of ICAM-1 and RANKL and RANKL-dependent osteoclast maturation. Thus, Rho-mediated signaling in osteoblasts seems to introduce major biases to bone resorption.

  18. Human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation mediated by vascular cell adhesion molecule-1: evidence for involvement of cell adhesion molecules in HTLV-1 biology.

    PubMed Central

    Hildreth, J E; Subramanium, A; Hampton, R A

    1997-01-01

    While studying the potential role of vascular cell adhesion molecule-1 (VCAM-1) in infection of endothelial cells by human immunodeficiency virus (HIV), we found that VCAM-1 can mediate human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation. Both expression-vector-encoded and endogenously expressed VCAM-1 supported fusion of uninfected cells with HTLV-1-infected cells. Fusion was obtained with cell lines carrying the HTLV-1 genome and expressing viral proteins but not with an HTLV-1-transformed cell line that does not express viral proteins. In clones of VCAM-1-transfected cells, the degree of syncytium formation observed directly reflected the level of VCAM-1 expression. Syncytium formation between HTLV-1-expressing cells and VCAM-1+ cells could be blocked with antiserum against HTLV-1 gp46 and with a monoclonal antibody (MAb) against VCAM-1. Fusion was not blocked by antiserum against HIV or a MAb against VLA-4, the physiological counter-receptor for VCAM-1. The results indicate that VCAM-1 can serve as an accessory molecule or potential coreceptor for HTLV-1-induced cell fusion and provide direct evidence of a role for cell adhesion molecules in the biology of HTLV-1. PMID:8995639

  19. Human immunodeficiency virus type 1 induces cellular polarization, intercellular adhesion molecule-1 redistribution, and multinucleated giant cell generation in human primary monocytes but not in monocyte-derived macrophages.

    PubMed

    Fais, S; Borghi, P; Gherardi, G; Logozzi, M; Belardelli, F; Gessani, S

    1996-12-01

    In this study, we evaluated the effects of human immunodeficiency virus type 1 (HIV-1) on some morphologic and functional changes in cultured human monocytes/macrophages at different stages of differentiation. Freshly isolated monocytes infected with HIV-1 24 hours after seeding exhibited marked morphologic changes such as uropod formation, polarization of intercellular adhesion molecule-1 (ICAM-1) on the cytoplasmic projection, the redistribution of alpha-actinin on cell-membrane dots, and an increased release of soluble ICAM-1. These changes preceded the increase in monocyte-monocyte fusion and the formation of multinucleated giant cells. In contrast, HIV-1 infection did not affect monocyte-derived macrophages in terms of either cellular polarization or multinucleated giant cell formation. Immunocytochemistry showed that HIV-1 matrix protein was present mostly in bi- and trinucleated cells, which suggests that multinucleated giant cells may represent a long-lived and highly productive cellular source of HIV. The treatment of the HIV-1-infected monocytes with azidodeoxythymidine virtually abolished all viral-induced morphofunctional changes. On the whole, these results indicate that blood monocytes and differentiated macrophages may be affected differently by HIV infection, as monocytes seem to be much more prone to polarize, undergo homotypic fusion, and form multinucleated giant cells. These changes may confer to HIV-infected monocytes an increased ability to transmigrate through endothelia into tissues, whereas differentiated macrophages may have a predominant role as a widespread reservoir of HIV.

  20. A single-arm, open-label, phase 2 clinical trial evaluating disease response following treatment with BI-505, a human anti-intercellular adhesion molecule-1 monoclonal antibody, in patients with smoldering multiple myeloma

    PubMed Central

    Wichert, Stina; Juliusson, Gunnar; Johansson, Åsa; Sonesson, Elisabeth; Teige, Ingrid; Wickenberg, Anna Teige; Frendeus, Björn; Korsgren, Magnus; Hansson, Markus

    2017-01-01

    Background Smoldering multiple myeloma (SMM) is an indolent disease stage, considered to represent the transition phase from the premalignant MGUS (Monoclonal Gammopathy of Undetermined Significance) state towards symptomatic multiple myeloma (MM). Even though this diagnosis provides an opportunity for early intervention, few treatment studies have been done and the current standard of care is observation until progression. BI-505, a monoclonal antibody directed against intercellular adhesion molecule 1 (ICAM-1) with promising anti-myeloma activity in preclinical trials, is a possible treatment approach for this patient category with potential to eliminate tumor cells with minimal long-term side effects. BI-505 was well tolerated in an earlier phase 1 trial. Methods and findings In this phase 2 trial the effects of BI-505 in patients with SMM were studied. Four patients were enrolled and three of them completed the first cycle of treatment defined as 5 doses of BI-505, a total of 43 mg/kg BW, over a 7-week period. In the three evaluable patients, BI-505 showed a benign safety profile. None of the patients achieved a response as defined per protocol. EudraCT number: 2012-004884-29. Conclusions The study was conducted to assess the efficacy, safety and pharmacodynamics of BI-505 in patients with SMM. BI-505 showed no clinically relevant efficacy on disease activity in these patients with SMM, even if well tolerated. Trial registration ClinicalTrials.gov Identifier: NCT01838369. PMID:28158311

  1. Fer and Fps/Fes participate in a Lyn-dependent pathway from FcepsilonRI to platelet-endothelial cell adhesion molecule 1 to limit mast cell activation.

    PubMed

    Udell, Christian M; Samayawardhena, Lionel A; Kawakami, Yuko; Kawakami, Toshiaki; Craig, Andrew W B

    2006-07-28

    Mast cells express the high affinity IgE receptor FcepsilonRI, which upon aggregation by multivalent antigens elicits signals that cause rapid changes within the mast cell and in the surrounding tissue. We previously showed that FcepsilonRI aggregation caused a rapid increase in phosphorylation of both Fer and Fps/Fes kinases in bone marrow-derived mast cells. In this study, we report that FcepsilonRI aggregation leads to increased Fer/Fps kinase activities and that Fer phosphorylation downstream of FcepsilonRI is independent of Syk, Fyn, and Gab2 but requires Lyn. Activated Fer/Fps readily phosphorylate the C terminus of platelet-endothelial cell adhesion molecule 1 (Pecam-1) on immunoreceptor tyrosine-based inhibitory motifs (ITIMs) and a non-ITIM residue (Tyr(700)) in vitro and in transfected cells. Mast cells devoid of Fer/Fps kinase activities display a reduction in FcepsilonRI aggregation-induced tyrosine phosphorylation of Pecam-1, with no defects in recruitment of Shp1/Shp2 phosphatases observed. Lyn-deficient mast cells display a dramatic reduction in Pecam-1 phosphorylation at Tyr(685) and a complete loss of Shp2 recruitment, suggesting a role as an initiator kinase for Pecam-1. Consistent with previous studies of Pecam-1-deficient mast cells, we observe an exaggerated degranulation response in mast cells lacking Fer/Fps kinases at low antigen dosages. Thus, Lyn and Fer/Fps kinases cooperate to phosphorylate Pecam-1 and activate Shp1/Shp2 phosphatases that function in part to limit mast cell activation.

  2. The Effect of Dexmedetomidine on Oxidative Stress Response Following Cerebral Ischemia-Reperfusion in Rats and the Expression of Intracellular Adhesion Molecule-1 (ICAM-1) and S100B

    PubMed Central

    Li, Yanwen; Liu, Shikun

    2017-01-01

    Background Ischemia-reperfusion injury of whole brain involves a complicated pathophysiology mechanism. Dexmedetomidine (Dex) has been shown to have neuro protective functions. This study observed the effect of Dex on serum S100B and cerebral intracellular adhesion molecule-1 (ICAM-1) in a rat model of cerebral ischemia-reperfusion. Material/Methods Healthy Sprague Dawley (SD) rats (males, 7 weeks old) were randomly divided into sham, model, and Dex groups (n=20 each). A cerebral ischemia-reperfusion model was prepared by clipping of the bilateral common carotid artery combined with hypotension. Dex (9 μg/kg) was infused intravenously immediately after reperfusion in the Dex group, while the other two groups received an equal volume of saline. Neural defect score (NDS) was measured at 6 hours, 24 hours, and 72 hours after surgery, with pathological observation of brain tissues. ELISA was then used to test serum S100B protein level. Malondialdehyde (MDA) and superoxide dismutase (SOD) were assayed by spectrometry. Nuclear factor-kappa B (NF-κB) and ICAM-1 levels were determined by real-time (RT)-PCR. Results Model rats had significant injury in the hippocampal CA1 region as shown by elevated NDS, S100B, and MDA levels, higher NF-κB and ICAM-1 mRNA expression, and lower SOD levels (p<0.05). Dex treatment improved pathological injury, decreased NDS, S100B, and MDA levels, decreased expression of mRNA of NF-κB and ICAM-1, and increased SOD levels. Conclusions Dex alleviated ischemia-reperfusion damage to rat brains, and inhibited NF-κB and ICAM-1 expression in brain tissues, possibly via inhibiting oxidative stress and inflammatory response. PMID:28212354

  3. T-lymphocyte responsiveness in murine schistosomiasis mansoni is dependent upon the adhesion molecules intercellular adhesion molecule-1, lymphocyte function-associated antigen-1, and very late antigen-4.

    PubMed Central

    Langley, J G; Boros, D L

    1995-01-01

    Granuloma formation in murine schistosomiasis is dependent on CD4+ Th lymphocytes and requires recruitment and accumulation of inflammatory cells at the site of egg deposition. The present study examined the role of three adhesion molecules, intercellular adhesion molecule-1 (ICAM-1), lymphocyte function-associated antigen-1 (LFA-1), and very late antigen-4 (VLA-4), that participate in cellular recruitment, interaction, and lymphocyte activation during in vitro activation of acutely and chronically infected spleen and liver granuloma lymphocytes. Blockade of ICAM-1, LFA-1, or VLA-4 by rat monoclonal antibody inhibited spleen and granuloma lymphocyte interleukin-2 (IL-2) and IL-4 production as well as lymphoproliferative responses at similar levels (66 to 87%). The down-modulated cytokine and proliferative responses of chronically infected lymphocytes were inhibited to the same extent as their acutely infected counterparts. Cell sorting analysis demonstrated that acutely and chronically infected splenic and granuloma lymphocytes expressed similar levels of LFA-1, ICAM-1, and VLA-4 and that more ICAM-1 was expressed on infected than on uninfected mouse lymphocytes. By exposure of cells to paired monoclonal antibodies at suboptimal doses, it was determined that whereas all three adhesion molecules may participate, only ICAM-1 and LFA-1 showed synergistic interactions in determining lymphocyte responsiveness. These data suggest that spleen and liver granuloma lymphocytes are equally well armed with functional adhesion receptors. Thus, ICAM-1, LFA-1, and VLA-4 play an important accessory role in inflammatory cytokine production and lymphocyte proliferation, and therefore these adhesion molecules may participate in the initiation and maintenance of the granulomatous inflammation. PMID:7558308

  4. The Effect of Dexmedetomidine on Oxidative Stress Response Following Cerebral Ischemia-Reperfusion in Rats and the Expression of Intracellular Adhesion Molecule-1 (ICAM-1) and S100B.

    PubMed

    Li, Yanwen; Liu, Shikun

    2017-02-17

    BACKGROUND Ischemia-reperfusion injury of whole brain involves a complicated pathophysiology mechanism. Dexmedetomidine (Dex) has been shown to have neuro protective functions. This study observed the effect of Dex on serum S100B and cerebral intracellular adhesion molecule-1 (ICAM-1) in a rat model of cerebral ischemia-reperfusion. MATERIAL AND METHODS Healthy Sprague Dawley (SD) rats (males, 7 weeks old) were randomly divided into sham, model, and Dex groups (n=20 each). A cerebral ischemia-reperfusion model was prepared by clipping of the bilateral common carotid artery combined with hypotension. Dex (9 μg/kg) was infused intravenously immediately after reperfusion in the Dex group, while the other two groups received an equal volume of saline. Neural defect score (NDS) was measured at 6 hours, 24 hours, and 72 hours after surgery, with pathological observation of brain tissues. ELISA was then used to test serum S100B protein level. Malondialdehyde (MDA) and superoxide dismutase (SOD) were assayed by spectrometry. Nuclear factor-kappa B (NF-kB) and ICAM-1 levels were determined by real-time (RT)-PCR. RESULTS Model rats had significant injury in the hippocampal CA1 region as shown by elevated NDS, S100B, and MDA levels, higher NF-κB and ICAM-1 mRNA expression, and lower SOD levels (p<0.05). Dex treatment improved pathological injury, decreased NDS, S100B, and MDA levels, decreased expression of mRNA of NF-κB and ICAM-1, and increased SOD levels. CONCLUSIONS Dex alleviated ischemia-reperfusion damage to rat brains, and inhibited NF-κB and ICAM-1 expression in brain tissues, possibly via inhibiting oxidative stress and inflammatory response.

  5. Mechanistic Control of Carcinoembryonic Antigen-related Cell Adhesion Molecule-1 (CEACAM1) Splice Isoforms by the Heterogeneous Nuclear Ribonuclear Proteins hnRNP L, hnRNP A1, and hnRNP M*

    PubMed Central

    Dery, Kenneth J.; Gaur, Shikha; Gencheva, Marieta; Yen, Yun; Shively, John E.; Gaur, Rajesh K.

    2011-01-01

    Carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1) is expressed in a variety of cell types and is implicated in carcinogenesis. Alternative splicing of CEACAM1 pre-mRNA generates two cytoplasmic domain splice variants characterized by the inclusion (L-isoform) or exclusion (S-isoform) of exon 7. Here we show that the alternative splicing of CEACAM1 pre-mRNA is regulated by novel cis elements residing in exon 7. We report the presence of three exon regulatory elements that lead to the inclusion or exclusion of exon 7 CEACAM1 mRNA in ZR75 breast cancer cells. Heterologous splicing reporter assays demonstrated that the maintenance of authentic alternative splicing mechanisms were independent of the CEACAM1 intron sequence context. We show that forced expression of these exon regulatory elements could alter CEACAM1 splicing in HEK-293 cells. Using RNA affinity chromatography, three members of the heterogeneous nuclear ribonucleoprotein family (hnRNP L, hnRNP A1, and hnRNP M) were identified. RNA immunoprecipitation of hnRNP L and hnRNP A1 revealed a binding motif located central and 3′ to exon 7, respectively. Depletion of hnRNP A1 or L by RNAi in HEK-293 cells promoted exon 7 inclusion, whereas overexpression led to exclusion of the variable exon. By contrast, overexpression of hnRNP M showed exon 7 inclusion and production of CEACAM1-L mRNA. Finally, stress-induced cytoplasmic accumulation of hnRNP A1 in MDA-MB-468 cells dynamically alters the CEACAM1-S:CEACAM1:L ratio in favor of the l-isoform. Thus, we have elucidated the molecular factors that control the mechanism of splice-site recognition in the alternative splicing regulation of CEACAM1. PMID:21398516

  6. Human peripheral blood eosinophils express a functional c-kit receptor for stem cell factor that stimulates very late antigen 4 (VLA-4)-mediated cell adhesion to fibronectin and vascular cell adhesion molecule 1 (VCAM-1).

    PubMed

    Yuan, Q; Austen, K F; Friend, D S; Heidtman, M; Boyce, J A

    1997-07-21

    We evaluated mature peripheral blood eosinophils for their expression of the surface tyrosine kinase, c-kit, the receptor for the stromal cell-derived cytokine, stem cell factor (SCF). Cytofluorographic analysis revealed that c-kit was expressed on the purified peripheral blood eosinophils from 8 of 8 donors (4 nonatopic and 4 atopic) (mean channel fluorescence intensity 2.0- 3. 6-fold, average 2.8 +/- 0.6-fold, greater than the negative control). The uniform and selective expression of c-kit by eosinophils was confirmed by immunohistochemical analysis of peripheral blood buffy coats. The functional integrity of c-kit was demonstrated by the capacity of 100 ng/ml (5 nM) of recombinant human (rh) SCF to increase eosinophil adhesion to 3, 10, and 30 microg/ml of immobilized FN40, a 40-kD chymotryptic fragment of plasma fibronectin, in 15 min by 7.7 +/- 1.4-, 5.3 +/- 3.3-, and 5.4 +/- 0. 2-fold, respectively, and their adhesion to 0.1, 0.5, and 1.0 microg/ml vascular cell adhesion molecule-1 (VCAM-1), by 12.7 +/- 9. 2-, 3.8 +/- 2.5-, and 1.7 +/- 0.6-fold, respectively. The SCF-stimulated adhesion occurred without concomitant changes in surface integrin expression, thereby indicating an avidity-based mechanism. rhSCF (100 ng/ml, 5 nM) was comparable to rh eotaxin (200 ng/ml, 24 nM) in stimulating adhesion. Cell adhesion to FN40 was completely inhibited with antibodies against the alpha4 and beta1 integrin subunits, revealing that the SCF/c-kit adhesion effect was mediated by a single integrin heterodimer, very late antigen 4 (VLA-4). Thus, SCF represents a newly recognized stromal ligand for the activation of eosinophils for VLA-4-mediated adhesion, which could contribute to the exit of these cells from the blood, their tissue localization, and their prominence in inflammatory lesions.

  7. Human Peripheral Blood Eosinophils Express a Functional c-kit Receptor for Stem Cell Factor that Stimulates Very Late Antigen 4 (VLA-4)–mediated Cell Adhesion to Fibronectin and Vascular Cell Adhesion Molecule 1 (VCAM-1)

    PubMed Central

    Yuan, Qian; Austen, K. Frank; Friend, Daniel S.; Heidtman, Matthew; Boyce, Joshua A.

    1997-01-01

    We evaluated mature peripheral blood eosinophils for their expression of the surface tyrosine kinase, c-kit, the receptor for the stromal cell–derived cytokine, stem cell factor (SCF). Cytofluorographic analysis revealed that c-kit was expressed on the purified peripheral blood eosinophils from 8 of 8 donors (4 nonatopic and 4 atopic) (mean channel fluorescence intensity 2.0– 3.6-fold, average 2.8 ± 0.6-fold, greater than the negative control). The uniform and selective expression of c-kit by eosinophils was confirmed by immunohistochemical analysis of peripheral blood buffy coats. The functional integrity of c-kit was demonstrated by the capacity of 100 ng/ml (5 nM) of recombinant human (rh) SCF to increase eosinophil adhesion to 3, 10, and 30 μg/ml of immobilized FN40, a 40-kD chymotryptic fragment of plasma fibronectin, in 15 min by 7.7 ± 1.4-, 5.3 ± 3.3-, and 5.4 ± 0.2-fold, respectively, and their adhesion to 0.1, 0.5, and 1.0 μg/ml vascular cell adhesion molecule-1 (VCAM-1), by 12.7 ± 9.2-, 3.8 ± 2.5-, and 1.7 ± 0.6-fold, respectively. The SCF-stimulated adhesion occurred without concomitant changes in surface integrin expression, thereby indicating an avidity-based mechanism. rhSCF (100 ng/ml, 5 nM) was comparable to rh eotaxin (200 ng/ml, 24 nM) in stimulating adhesion. Cell adhesion to FN40 was completely inhibited with antibodies against the α4 and β1 integrin subunits, revealing that the SCF/c-kit adhesion effect was mediated by a single integrin heterodimer, very late antigen 4 (VLA-4). Thus, SCF represents a newly recognized stromal ligand for the activation of eosinophils for VLA-4–mediated adhesion, which could contribute to the exit of these cells from the blood, their tissue localization, and their prominence in inflammatory lesions. PMID:9221761

  8. Negative Association of Circulating MicroRNA-126 with High-sensitive C-reactive Protein and Vascular Cell Adhesion Molecule-1 in Patients with Coronary Artery Disease Following Percutaneous Coronary Intervention

    PubMed Central

    Wang, Jun-Nan; Yan, You-You; Guo, Zi-Yuan; Jiang, Ya-Juan; Liu, Lu-Lu; Liu, Bin

    2016-01-01

    Background: Percutaneous coronary intervention (PCI) causes endothelial damage, resulting in an inflammatory response with elevation of markers such as high-sensitive C-reactive protein (hs-CRP) and vascular cell adhesion molecule-1 (VCAM-1), which are associated with restenosis after PCI. Evidence suggests that microRNA-126 (miR-126) plays an important role in vascular inflammation, but its correlation with PCI-mediated inflammation has not been investigated. In this study, we investigated the effect of PCI on circulating miR-126 and inflammation markers such as hs-CRP and VCAM-1. Methods: We enrolled 130 patients with coronary artery disease (CAD) in the Second Hospital of Jilin University from October 2015 to December 2015. Among them, 82 patients with CAD, defined as at least one major epicardial vessel with >70% stenosis who planned to undergo PCI, were divided into acute coronary syndrome (ACS) group (46 patients) and stable angina (SA) group (36 patients). Forty-eight patients confirmed by coronary angiography without PCI were used as controls. The plasmas of all patients were collected prior to PCI and at 30 min, 24 h, and 72 h after PCI. The plasma VCAM-1 and hs-CRP were detected by enzyme-linked immunosorbent assay, and the miR-126 was evaluated by quantitative reverse transcription-polymerase chain reaction. Results: Plasma concentrations of hs-CRP and VCAM-1 in patients with either ACS (n = 46) or SA (n = 36) were significantly higher than in controls (n = 48) (P < 0.01) prior to PCI, and increased further at 24 h and 72 h after PCI, compared with prior PCI. Moreover, VCAM-1 was positively correlated with balloon time and pressure. In contrast, the plasma concentration of miR-126 was significantly lower in patients with CAD than in controls, and further decreased with time post-PCI. A negative correlation was observed between miR-126 and hs-CRP and VCAM-1 at 72 h after PCI. Conclusion: There was a negative correlation of miR-126 with the PCI

  9. Atmospheric chemistry of cis-CF3CHdbnd CHCl (HCFO-1233zd(Z)): Kinetics of the gas-phase reactions with Cl atoms, OH radicals, and O3

    NASA Astrophysics Data System (ADS)

    Andersen, Lene Løffler; Østerstrøm, Freja From; Sulbaek Andersen, Mads P.; Nielsen, Ole John; Wallington, Timothy J.

    2015-10-01

    FTIR smog chamber techniques were used to measure the rate coefficients k(Cl + cis-CF3CHdbnd CHCl) = (6.26 ± 0.84) × 10-11, k(OH + cis-CF3CHdbnd CHCl) = (8.45 ± 1.52) × 10-13, and k(O3 + cis-CF3CHdbnd CHCl) = (1.53 ± 0.12) × 10-21 cm3 molecule-1 s-1. The atmospheric lifetime of cis-CF3CHdbnd CHCl is determined by reaction with OH radicals and is estimated to be 14 days. The infrared spectrum of cis-CF3CHdbnd CHCl was recorded and the integrated absorption over the range 600-2000 cm-1 was measured to be (1.48 ± 0.07) × 10-16 cm molecule-1. Accounting for non-uniform horizontal and vertical mixing leads to a GWP100 value of essentially zero. Correction to account for unwanted Cl atom chemistry in our previous relative rate study of the kinetics of the reaction of OH with trans-CF3CHdbnd CHCl gives k(OH + trans-CF3CHdbnd CHCl) = (3.61 ± 0.37) × 10-13 cm3 molecule-1 s-1.

  10. Photochemical properties of trans-1-chloro-3,3,3-trifluoropropene (trans-CHCl═CHCF3): OH reaction rate constant, UV and IR absorption spectra, global warming potential, and ozone depletion potential.

    PubMed

    Orkin, Vladimir L; Martynova, Larissa E; Kurylo, Michael J

    2014-07-17

    Measurements of the rate constant for the gas-phase reactions of OH radicals with trans-1-chloro-3,3,3-trifluoropropene (trans-CHCl═CHCF3) were performed using a flash photolysis resonance-fluorescence technique over the temperature range 220-370 K. The reaction rate constant exhibits a noticeable curvature of the temperature dependence in the Arrhenius plot, which can be represented by the following expression: kt-CFP (220-370 K) = 1.025 × 10(-13) × (T/298)(2.29) exp(+384/T) cm(3 )molecule(-1) s(-1). The room-temperature rate constant was determined to be kt-CFP (298 K) = (3.29 ± 0.10) × 10(-13) cm(3) molecule(-1) s(-1), where the uncertainty includes both two standard errors (statistical) and the estimated systematic error. For atmospheric modeling purposes, the rate constant below room temperature can be represented by the following expression: kt-CFP (220-298 K) = (7.20 ± 0.46) × 10(-13) exp[-(237 ± 16)/T] cm(3) molecule(-1) s(-1). There was no difference observed between the rate constants determined at 4 kPa (30 Torr) and 40 kPa (300 Torr) at both 298 and 370 K. The UV and IR absorption cross sections of this compound were measured at room temperature. The atmospheric lifetime, global warming potential, and ozone depletion potential of trans-CHCl═CHCF3 were estimated.

  11. Atmospheric fate of a series of carbonyl nitrates: photolysis frequencies and OH-oxidation rate constants.

    PubMed

    Suarez-Bertoa, R; Picquet-Varrault, B; Tamas, W; Pangui, E; Doussin, J-F

    2012-11-20

    Multifunctional organic nitrates are potential NO(x) reservoirs whose atmospheric chemistry is somewhat little known. They could play an important role in the spatial distribution of reactive nitrogen species and consequently in ozone formation and distribution in remote areas. In this work, the rate constants for the reaction with OH radical and the photolysis frequencies of α-nitrooxyacetone, 3-nitrooxy-2-butanone, and 3-methyl-3-nitrooxy-2-butanone have been determined at room temperature at 1000 mbar total pressure of synthetic air. The rate constants for the OH oxidation were measured using the relative rate technique, with methanol as reference compound. The following rate constants were obtained for the reaction with OH: k(OH) = (6.7 ± 2.5) × 10(-13) cm(3) molecule(-1) s(-1) for α-nitrooxyacetone, (10.6 ± 4.1) × 10(-13) cm(3) molecule(-1) s(-1) for 3-nitrooxy-2-butanone, and (2.6 ± 0.9) × 10(-13) cm(3) molecule(-1) s(-1) for 3-methyl-3-nitrooxy-2-butanone. The corresponding photolysis frequencies extrapolated to typical atmospheric conditions for July first at noon at 40° latitude North were (4.8 ± 0.3) × 10(-5) s(-1), (5.7 ± 0.3) × 10(-5) s(-1), and (7.4 ± 0.2) × 10(-5) s(-1), respectively. The data show that photolysis is a major atmospheric sink for these organic nitrates.

  12. Tumor necrosis factor-alpha enhances neutrophil adhesiveness: induction of vascular cell adhesion molecule-1 via activation of Akt and CaM kinase II and modifications of histone acetyltransferase and histone deacetylase 4 in human tracheal smooth muscle cells.

    PubMed

    Lee, Chiang-Wen; Lin, Chih-Chung; Luo, Shue-Fen; Lee, Hui-Chun; Lee, I-Ta; Aird, William C; Hwang, Tsong-Long; Yang, Chuen-Mao

    2008-05-01

    Up-regulation of vascular cell adhesion molecule-1 (VCAM-1) involves adhesions between both circulating and resident leukocytes and the human tracheal smooth muscle cells (HTSMCs) during airway inflammatory reaction. We have demonstrated previously that tumor necrosis factor (TNF)-alpha-induced VCAM-1 expression is regulated by mitogen-activated protein kinases, nuclear factor-kappaB, and p300 activation in HTSMCs. In addition to this pathway, phosphorylation of Akt and CaM kinase II has been implicated in histone acetyltransferase and histone deacetylase 4 (HDAC4) activation. Here, we investigated whether these different mechanisms participated in TNF-alpha-induced VCAM-1 expression and enhanced neutrophil adhesion. TNF-alpha significantly increased HTSMC-neutrophil adhesions, and this effect was associated with increased expression of VCAM-1 on the HTSMCs and was blocked by the selective inhibitors of Src [4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]-pyrimidine (PP1)], epidermal growth factor receptor [EGFR; 4-(3'-chloroanilino)-6,7-dimethoxy-quinazoline, (AG1478)], phosphatidylinositol 3-kinase (PI3K) [2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one hydrochloride(LY294002) and wortmannin],calcium[1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester; BAPTA-AM], phosphatidylinositol-phospholipase C (PLC) [1-[6-[[17beta-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione (U73122)], protein kinase C (PKC) [12-(2-cyanoethyl)-6,7,12, 13-tetrahydro-13-methyl-5-oxo-5H-indolo(2,3-a)pyrrolo(3,4-c)-carbazole (Gö6976), rottlerin, and 3-1-[3-(amidinothio)propyl-1H-indol-3-yl]-3-(1-methyl-1H-indol-3-yl) maleimide (bisindolylmaleimide IX) (Ro 31-8220)], CaM (calmidazolium chloride), CaM kinase II [(8R(*),9S(*),11S(*))-(-)-9-hydroxy-9-methoxycarbonyl-8-methyl-14-n-propoxy-2,3,9, 10-tetrahydro-8,11-epoxy, 1H,8H, 11H-2,7b,11a-triazadibenzo[a,g]cycloocta[cde]trinden-1-one (KT5926) and 1-[N,O-bis(5-isoquinolinesulfonyl

  13. Atmospheric chemistry of isoflurane, desflurane, and sevoflurane: kinetics and mechanisms of reactions with chlorine atoms and OH radicals and global warming potentials.

    PubMed

    Sulbaek Andersen, Mads P; Nielsen, Ole J; Karpichev, Boris; Wallington, Timothy J; Sander, Stanley P

    2012-06-21

    The smog chamber/Fourier-transform infrared spectroscopy (FTIR) technique was used to measure the rate coefficients k(Cl + CF(3)CHClOCHF(2), isoflurane) = (4.5 ± 0.8) × 10(-15), k(Cl + CF(3)CHFOCHF(2), desflurane) = (1.0 ± 0.3) × 10(-15), k(Cl + (CF(3))(2)CHOCH(2)F, sevoflurane) = (1.1 ± 0.1) × 10(-13), and k(OH + (CF(3))(2)CHOCH(2)F) = (3.5 ± 0.7) × 10(-14) cm(3) molecule(-1) in 700 Torr of N(2)/air diluent at 295 ± 2 K. An upper limit of 6 × 10(-17) cm(3) molecule(-1) was established for k(Cl + (CF(3))(2)CHOC(O)F). The laser photolysis/laser-induced fluorescence (LP/LIF) technique was employed to determine hydroxyl radical rate coefficients as a function of temperature (241-298 K): k(OH + CF(3)CHFOCHF(2)) = (7.05 ± 1.80) × 10(-13) exp[-(1551 ± 72)/T] cm(3) molecule(-1); k(296 ± 1 K) = (3.73 ± 0.08) × 10(-15) cm(3) molecule(-1), and k(OH + (CF(3))(2)CHOCH(2)F) = (9.98 ± 3.24) × 10(-13) exp[-(969 ± 82)/T] cm(3) molecule(-1); k(298 ± 1 K) = (3.94 ± 0.30) × 10(-14) cm(3) molecule(-1). The rate coefficient of k(OH + CF(3)CHClOCHF(2), 296 ± 1 K) = (1.45 ± 0.16) × 10(-14) cm(3) molecule(-1) was also determined. Chlorine atoms react with CF(3)CHFOCHF(2) via H-abstraction to give CF(3)CFOCHF(2) and CF(3)CHFOCF(2) radicals in yields of approximately 83% and 17%. The major atmospheric fate of the CF(3)C(O)FOCHF(2) alkoxy radical is decomposition via elimination of CF(3) to give FC(O)OCHF(2) and is unaffected by the method used to generate the CF(3)C(O)FOCHF(2) radicals. CF(3)CHFOCF(2) radicals add O(2) and are converted by subsequent reactions into CF(3)CHFOCF(2)O alkoxy radicals, which decompose to give COF(2) and CF(3)CHFO radicals. In 700 Torr of air 82% of CF(3)CHFO radicals undergo C-C scission to yield HC(O)F and CF(3) radicals with the remaining 18% reacting with O(2) to give CF(3)C(O)F. Atmospheric oxidation of (CF(3))(2)CHOCH(2)F gives (CF(3))(2)CHOC(O)F in a molar yield of 93 ± 6% with CF(3)C(O)CF(3) and HCOF as minor products. The IR

  14. Direct measurement of Criegee intermediate (CH2OO) reactions with acetone, acetaldehyde, and hexafluoroacetone.

    PubMed

    Taatjes, Craig A; Welz, Oliver; Eskola, Arkke J; Savee, John D; Osborn, David L; Lee, Edmond P F; Dyke, John M; Mok, Daniel W K; Shallcross, Dudley E; Percival, Carl J

    2012-08-14

    Criegee biradicals, i.e., carbonyl oxides, are critical intermediates in ozonolysis and have been implicated in autoignition chemistry and other hydrocarbon oxidation systems, but until recently the direct measurement of their gas-phase kinetics has not been feasible. Indirect determinations of Criegee intermediate kinetics often rely on the introduction of a scavenger molecule into an ozonolysis system and analysis of the effects of the scavenger on yields of products associated with Criegee intermediate reactions. Carbonyl species, in particular hexafluoroacetone (CF(3)COCF(3)), have often been used as scavengers. In this work, the reactions of the simplest Criegee intermediate, CH(2)OO (formaldehyde oxide), with three carbonyl species have been measured by laser photolysis/tunable synchrotron photoionization mass spectrometry. Diiodomethane photolysis produces CH(2)I radicals, which react with O(2) to yield CH(2)OO + I. The formaldehyde oxide is reacted with a large excess of a carbonyl reactant and both the disappearance of CH(2)OO and the formation of reaction products are monitored. The rate coefficient for CH(2)OO + hexafluoroacetone is k(1) = (3.0 ± 0.3) × 10(-11) cm(3) molecule(-1) s(-1), supporting the use of hexafluoroacetone as a Criegee-intermediate scavenger. The reactions with acetaldehyde, k(2) = (9.5 ± 0.7) × 10(-13) cm(3) molecule(-1) s(-1), and with acetone, k(3) = (2.3 ± 0.3) × 10(-13) cm(3) molecule(-1) s(-1), are substantially slower. Secondary ozonides and products of ozonide isomerization are observed from the reactions of CH(2)OO with acetone and hexafluoroacetone. Their photoionization spectra are interpreted with the aid of quantum-chemical and Franck-Condon-factor calculations. No secondary ozonide was observable in the reaction of CH(2)OO with acetaldehyde, but acetic acid was identified as a product under the conditions used (4 Torr and 293 K).

  15. Abstraction kinetics of H-atom by OH radical from pinonaldehyde (C10H16O2): ab initio and transition-state theory calculations.

    PubMed

    Dash, Manas Ranjan; Rajakumar, B

    2012-06-21

    The kinetics and abstraction rate coefficients of hydroxyl radical (OH) reaction with pinonaldehyde were computed using G3(MP2) theory and transition-state theory (TST) between 200 and 400 K. Structures of the reactants, reaction complexes (RCs), product complexes (PCs), transition states (TSs), and products were optimized at the MP2(FULL)/6-31G* level of theory. Fifteen transition states were identified for the title reaction and confirmed by intrinsic reaction coordinate (IRC) calculations. The contributions of all the individual hydrogens in the substrate molecule to the total reaction are computed. The quantum mechanical tunneling effect was computed using Wigner's and Eckart's methods (both symmetrical and unsymmetrical methods). The reaction exhibits a negative temperature dependent rate coefficient, k(T) = (1.97 ± 0.34) × 10(-13) exp[(1587 ± 48)/T] cm(3) molecule(-1) s(-1), k(T) = (3.02 ± 0.56) × 10(-13) exp[(1534 ± 52/T] cm(3) molecule(-1) s(-1), and k(T) = (4.71 ± 1.85) × 10(-14) exp[(2042 ± 110)/T] cm(3) molecule(-1) s(-1) with Wigner's, Eckart's symmetrical, and Eckart's unsymmetrical tunneling corrections, respectively. Theoretically calculated rate coefficients are found to be in good agreement with the experimentally measured ones and other theoretical results. It is shown that hydrogen abstraction from -CHO position is the major channel, whereas H-abstraction from -COCH(3) is negligible. The atmospheric lifetime of pinonaldehyde is computed to be few hours and found to be in excellent agreement with the experimentally estimated ones.

  16. A comparison of the updated very high resolution model RegCM3_10km with the previous version RegCM3_25km over the complex terrain of Greece: present and future projections

    NASA Astrophysics Data System (ADS)

    Tolika, Konstantia; Anagnostopoulou, Christina; Velikou, Kondylia; Vagenas, Christos

    2016-11-01

    The ability of a fine resolution regional climate model (10 × 10 km) in simulating efficiently the climate characteristics (temperature, precipitation, and wind) over Greece, in comparison to the previous version of the model with a 25 × 25 km resolution, is examined and analyzed in the present study. Overall, the results showed that the finer resolution model presented a better skill in generating low winter temperatures at high altitudinal areas, the temperature difference between the islands and the surrounding sea, high rainfall totals over the mountainous areas, the thermal storms during summer, and the wind maxima over the Aegean Sea. Regarding the future projections, even though the two models agree on the climatic signal, differences are found mainly to the magnitude of change of the selected parameters. Finally, it was found that at higher pressure levels, the present day projections of the two models do not show significant differences since the topography and terrain does not play such an important role as the general atmospheric circulation.

  17. Regional Climate System Feedbacks from Land Use Changes in Southeast Asia: A sensitivity study using RegCM3

    NASA Astrophysics Data System (ADS)

    Stauffer, H. L.; Sloan, L. C.

    2008-12-01

    Many observational and modeling studies have demonstrated the strong links between changes in land use and climate, and anthropogenic alterations of the land surface are now recognized to have consequences at the local, regional, and global scales. However, the effects of such changes on the local and regional climate system are not well understood, and yet, are critical to understanding future regional climate change. In Southeast Asia, a region which has experienced rapid and dramatic anthropogenic land use change in the 20th Century, shifts in precipitation patterns in response to these changes have been documented from observational data. While most climate modeling studies of the Southeast Asian region have employed low- resolution general circulation models, previous regional modeling studies for Southeast Asia have focused on land use change feedbacks on timescales from days to months and only for portions of the region. This study employs a high-resolution regional climate model centered on the Southeast Asian region, including Indochina, the Malay Peninsula, the Indonesian archipelago, the Philippines, and parts of Papua New Guinea and northern Australia, to conduct two simulations over the 30-year period between 1975 and 2005. Specifically, the simulations are used to compare climates with natural potential vegetation to those with modern land use as land cover, including differences in seasonal and annual temperature and precipitation distributions.

  18. Application of ICTP RegCM3's New Dust Model to Modern N. America: Challenges and Questions

    NASA Astrophysics Data System (ADS)

    O'Brien, T. A.; Hutchison, K. A.; Sloan, L. C.; Solmon, F.

    2008-12-01

    Comparison of results from the new ICTP Regional Climate Model (RCM) dust module to observational data from the IMPROVE network shows that the RCM correctly predicts emission sources and the spatial distribution of dust, but it overestimates the concentration of dust by a factor of one hundred. We show that this overestimation of dust emission is essentially independent of the soil-moisture-effect scheme, threshold velocity scheme, and model resolution (vertical and horizontal). We find that modification of soil properties in the RCM's saltation/sandblasting parametrization can reduce emissions and put dust concentrations in the right order of magnitude. Lack of size resolved dust data for North America make it difficult to asses whether this modification affects the validity of the model in terms of size distributions and indirectly in terms of dust optical effects.

  19. An investigation into linearity with cumulative emissions of the climate and carbon cycle response in HadCM3LC

    NASA Astrophysics Data System (ADS)

    Liddicoat, S. K.; Booth, B. B. B.; Joshi, M. M.

    2016-06-01

    We investigate the extent to which global mean temperature, precipitation, and the carbon cycle are constrained by cumulative carbon emissions throughout four experiments with a fully coupled climate-carbon cycle model. The paired experiments adopt contrasting, idealised approaches to climate change mitigation at different action points this century, with total emissions rising to more than two trillion tonnes of carbon (TtC). For each pair, the contrasting mitigation approaches—capping emissions early versus reducing them to zero a few decades later—cause their cumulative emissions trajectories to diverge initially, then converge, cross, and diverge again. We find that global mean temperature is linear with cumulative emissions across all experiments, although differences of up to 1.5 K exist regionally when the trajectories of total carbon emitted during the course of the two scenarios coincide, for both pairs of experiments. Interestingly, although the oceanic precipitation response scales with cumulative emissions, the global precipitation response does not, due to a decrease in precipitation over land above emissions of around one TtC. Most carbon fluxes are less well constrained by cumulative emissions as they reach two trillion tonnes. The opposing mitigation approaches have different consequences for the Amazon rainforest, which affects the linearity with which the carbon cycle responds to cumulative emissions. The average Transient Climate Response to cumulative carbon Emissions (TCRE) is 1.95 K TtC-1, at the upper end of the Intergovernmental Panel on Climate Change’s range of 0.8-2.5 K TtC-1.

  20. Sea surface temperatures of the mid-Piacenzian Warm Period: A comparison of PRISM3 and HadCM3

    USGS Publications Warehouse

    Dowsett, H.J.; Haywood, A.M.; Valdes, P.J.; Robinson, M.M.; Lunt, D.J.; Hill, D.J.; Stoll, D.K.; Foley, K.M.

    2011-01-01

    It is essential to document how well the current generation of climate models performs in simulating past climates to have confidence in their ability to project future conditions. We present the first global, in-depth comparison of Pliocene sea surface temperature (SST) estimates from a coupled ocean–atmosphere climate model experiment and a SST reconstruction based on proxy data. This enables the identification of areas in which both the climate model and the proxy dataset require improvement.In general, the fit between model-produced SST anomalies and those formed from the available data is very good. We focus our discussion on three regions where the data–model anomaly exceeds 2 °C. 1) In the high latitude North Pacific, a systematic model error may result in anomalies that are too cold. Also, the deeper Pliocene thermocline may cause disagreement along the California margin; either the upwelling in the model is too strong or the modeled thermocline is not deep enough. 2) In the North Atlantic, the model predicts cooling in the center of a data-based warming trend that steadily increases with latitude from + 1.5 °C to >+ 6 °C. The discrepancy may arise because the modeled North Atlantic Current is too zonal compared to reality, which is reinforced by the lowering of the altitude of the Pliocene Western Cordillera Mountains. In addition, the model's use of modern bathymetry in the higher latitudes may have led the model to underestimate the northward penetration of warmer surface water into the Arctic. 3) Finally, though the data and model show good general agreement across most of the Southern Ocean, a few locations show offsets due to the modern land–sea mask used in the model.Additional considerations could account for many of the modest data–model anomalies, such as differences between calibration climatologies, the oversimplification of the seasonal cycle, and differences between SST proxies (i.e. seasonality and water depth). New SST estimates from data-sparse and regionally important areas will greatly enhance our ability to judge model performance.

  1. CF3CF=CH2 and (Z)-CF3CF=CHF: temperature dependent OH rate coefficients and global warming potentials.

    PubMed

    Papadimitriou, Vassileios C; Talukdar, Ranajit K; Portmann, R W; Ravishankara, A R; Burkholder, James B

    2008-02-14

    Rate coefficients over the temperature range 206-380 K are reported for the gas-phase reaction of OH radicals with 2,3,3,3-tetrafluoropropene (CF(3)CF=CH(2)), k(1)(T), and 1,2,3,3,3-pentafluoropropene ((Z)-CF(3)CF=CHF), k(2)(T), which are major components in proposed substitutes for HFC-134a (CF(3)CFH(2)) in mobile air-conditioning units. Rate coefficients were measured under pseudo-first-order conditions in OH using pulsed-laser photolysis to produce OH and laser-induced fluorescence to detect it. Rate coefficients were found to be independent of pressure between 25 and 600 Torr (He, N(2)). For CF(3)CF=CH(2), the rate coefficients, within the measurement uncertainty, are given by the Arrhenius expression k(1)(T)=(1.26+/-0.11) x 10(-12) exp[(-35+/-10)/T] cm(3) molecule(-1) s(-1) where k(1)(296 K)=(1.12+/-0.09) x 10(-12) cm(3) molecule(-1) s(-1). For (Z)-CF(3)CF=CHF, the rate coefficients are given by the non-Arrhenius expression k(2)(T)=(1.6+/-0.2) x 10(-18)T(2) exp[(655+/-50)/T] cm(3) molecule(-1) s(-1) where k(2)(296 K)=(1.29+/-0.06) x 10(-12) cm(3) molecule(-1) s(-1). Over the temperature range most relevant to the atmosphere, 200-300 K, the Arrhenius expression k(2)(T)=(7.30+/-0.7) x 10(-13) exp[(165+/-20)/T] cm(3) molecule(-1) s(-1) reproduces the measured rate coefficients very well and can be used in atmospheric model calculations. The quoted uncertainties in the rate coefficients are 2sigma (95% confidence interval) and include estimated systematic errors. The global warming potentials for CF(3)CF=CH(2) and (Z)-CF(3)CF=CHF were calculated to be <4.4 and <3.6, respectively, for the 100 year time horizon using infrared absorption cross sections measured in this work, and atmospheric lifetimes of 12 and 10 days that are based solely on OH reactive loss.

  2. Angiogenesis in Platelet Endothelial Cell Adhesion Molecule-1-Null Mice

    PubMed Central

    Cao, Gaoyuan; Fehrenbach, Melane L.; Williams, James T.; Finklestein, Jeffrey M.; Zhu, Jing-Xu; DeLisser, Horace M.

    2009-01-01

    Platelet endothelial cell adhesion molecule (PECAM)-1 has been previously implicated in endothelial cell migration; additionally, anti-PECAM-1 antibodies have been shown to inhibit in vivo angiogenesis. Studies were therefore performed with PECAM-1-null mice to further define the involvement of PECAM-1 in blood vessel formation. Vascularization of subcutaneous Matrigel implants as well as tumor angiogenesis were both inhibited in PECAM-1-null mice. Reciprocal bone marrow transplants that involved both wild-type and PECAM-1-deficient mice revealed that the impaired angiogenic response resulted from a loss of endothelial, but not leukocyte, PECAM-1. In vitro wound migration and single-cell motility by PECAM-1-null endothelial cells were also compromised. In addition, filopodia formation, a feature of motile cells, was inhibited in PECAM-1-null endothelial cells as well as in human endothelial cells treated with either anti-PECAM-1 antibody or PECAM-1 siRNA. Furthermore, the expression of PECAM-1 promoted filopodia formation and increased the protein expression levels of Cdc42, a Rho GTPase that is known to promote the formation of filopodia. In the developing retinal vasculature, numerous, long filamentous filopodia, emanating from endothelial cells at the tips of angiogenic sprouts, were observed in wild-type animals, but to a lesser extent in the PECAM-1-null mice. Together, these data further establish the involvement of endothelial PECAM-1 in angiogenesis and suggest that, in vivo, PECAM-1 may stimulate endothelial cell motility by promoting the formation of filopodia. PMID:19574426

  3. Atmospheric chemistry of (Z)-CF3CH═CHCF3: OH radical reaction rate coefficient and global warming potential.

    PubMed

    Baasandorj, Munkhbayar; Ravishankara, A R; Burkholder, James B

    2011-09-29

    Rate coefficients, k, for the gas-phase reaction of the OH radical with (Z)-CF(3)CH═CHCF(3) (cis-1,1,1,4,4,4-hexafluoro-2-butene) were measured under pseudo-first-order conditions in OH using pulsed laser photolysis (PLP) to produce OH and laser-induced fluorescence (LIF) to detect it. Rate coefficients were measured over a range of temperatures (212-374 K) and bath gas pressures (20-200 Torr; He, N(2)) and found to be independent of pressure over this range of conditions. The rate coefficient has a non-Arrhenius behavior that is well-described by the expression k(1)(T) = (5.73 ± 0.60) × 10(-19) × T(2) × exp[(678 ± 10)/T] cm(3) molecule(-1) s(-1) where k(1)(296 K) was measured to be (4.91 ± 0.50) × 10(-13) cm(3) molecule(-1) s(-1) and the uncertainties are at the 2σ level and include estimated systematic errors. Rate coefficients for the analogous OD radical reaction were determined over a range of temperatures (262-374 K) at 100 Torr (He) to be k(2)(T) = (4.81 ± 0.20) × 10(-19) × T(2) × exp[(776 ± 15)/T], with k(2)(296 K) = (5.73 ± 0.50) × 10(-13) cm(3) molecule(-1) s(-1). OH radical rate coefficients were also measured at 296, 345, and 375 K using a relative rate technique and found to be in good agreement with the PLP-LIF results. A room-temperature rate coefficient for the O(3) + (Z)-CF(3)CH═CHCF(3) reaction was measured using an absolute method with O(3) in excess to be <6 × 10(-21) cm(3) molecule(-1) s(-1). The atmospheric lifetime of (Z)-CF(3)CH═CHCF(3) due to loss by OH reaction was estimated to be ~20 days. Infrared absorption spectra of (Z)-CF(3)CH═CHCF(3) measured in this work were used to determine a (Z)-CF(3)CH═CHCF(3) global warming potential (GWP) of ~9 for the 100 year time horizon. A comparison of the OH reactivity of (Z)-CF(3)CH═CHCF(3) with other unsaturated fluorinated compounds is presented.

  4. Experimental and computational investigation on the gas phase reaction of p-cymene with Cl atoms.

    PubMed

    Dash, Manas Ranjan; Srinivasulu, G; Rajakumar, B

    2015-01-29

    The rate coefficient for the gas-phase reaction of Cl atoms with p-cymene was determined as a function of temperature (288-350 K) and pressure (700-800 Torr) using the relative rate technique, with 1,3-butadiene and ethylene as reference compounds. Cl atoms were generated by UV photolysis of oxalyl chloride ((COCl)2) at 254 nm, and nitrogen was used as the diluent gas. The rate coefficient for the reaction of Cl atoms with p-cymene at 298 K was measured to be (2.58 ± 1.55) × 10(-10) cm(3) molecule(-1) s(-1). The kinetic data obtained over the temperature range 288-350 K were used to derive an Arrhenius expression: k(T) = (9.36 ± 2.90) × 10(-10) exp[-(488 ± 98)/T] cm(3) molecule(-1) s(-1). Theoretical kinetic calculations were also performed for the title reaction using canonical variational transition state theory (CVT) with small curvature tunneling (SCT) between 250 and 400 K. The calculated rate coefficients obtained over the temperature range 250-400 K were used to derive an Arrhenius expression: k(T) = 5.41 × 10(-13) exp[1837/T] cm(3) molecule(-1) s(-1). Theoretical study indicated that addition channels contribute maximum to the total reaction and H-abstraction channels can be neglected. The atmospheric lifetime (τ) of p-cymene due to its reactions with various tropospheric oxidants was estimated, and it was concluded that the reactions of p-cymene with Cl atoms may compete with OH radicals in the marine boundary layer and in coastal urban areas where the concentration of Cl atoms is high.

  5. The development of the concepts of heat and temperature in 10-13 year-olds

    NASA Astrophysics Data System (ADS)

    Shayer, Michael; Wylam, Hugh

    A crucial issue in the theory of science education at present is the problem of how much it is possible to generalize about steps in understanding achieved by different pupils in a given topic. Many Piagetians believe that there are qualitatively different steps followed in the same succession by all pupils: some Ausubelians believe that there is no such order, and that for each pupil the best criterion for the teacher is the pupil's present knowledge. One purpose of this study is to shed light on this issue. The study to be described made use of three inputs. The development of a technique of psychometrising Piaget by an English team based at London University provided a way of extending a study by Erickson (1977) of personal conceptual inventories to testing a sample of 200 children by a 68 item demonstrated group-test. In addition a team of curriculum developers had provided a tentative list of objectives for the teaching of Heat to Middle School students. The schools in which the study was carried out wished to know which of the objectives were more suitable for 9 or for 12 year-olds. The group-test utilized descriptors both from the Erickson study and from the list of curriculum objectives. In addition to the Heat test a Piagetian group-test (NFER, 1979) in the area of Volume and Heaviness was administered to see whether the development of concepts of Heat could be mapped onto Piagetian stages of development. Test-items in nine aspects of heat were written, with some of the experiments to be demonstrated to the class. These aspects included Conduction, Expansion, Composition of Heat, Temperature Scales, Changes of State, etc. Factor analysis of the data showed that one factor was sufficient to explain the common-factor variance of the heat scales, and that the Heat test was also unifactor with the Piagetian test. It was possible to describe Early Concrete, Late Concrete and Early Formal levels of understanding in the area of Heat and Temperature. In this particular case it appears that the hypothesis of a number of different developmental paths, dependent on previous experience, cannot be sustained. It is not claimed that this would be true of all cognitive development, particularly where culture-specific myths may be involved.

  6. Research Priorities in Childhood Disability: Conference Proceedings (London, Ontario, Canada, May 10-13, 1988).

    ERIC Educational Resources Information Center

    Easter Seal Research Inst., Don Mills (Ontario).

    The conference reported in this document utilized a conceptual matrix to organize presentations on research priorities in prevention, definitive treatment, and ongoing management of impairment, disability, and handicap. Ten research strategy recommendations developed at the conference are offered for implementation by The Easter Seal Research…

  7. Insensitive Munitions and Energetic Materials Symposium Held on 10-13 March 2003

    DTIC Science & Technology

    2003-03-13

    Evaluation of Sympathetic Detonation Shielding Concepts for Ship-Stowed Munitions by Edward J. O’Connor, NSWC SESSION 3: Formulation I CL-20 PAX...Inc. A Comparison of Techniques for Modeling XDT in Explosives and Propellants by Edward J. O’Connor, NSWC Dahlgren Division SESSION 7a

  8. 1991 SEM Spring Conference on Experimental Mechanics, Milwaukee, WI, June 10-13, 1991, Proceedings

    NASA Astrophysics Data System (ADS)

    The present volume on experimental mechanics discusses current trends in elastoplastic fracture, photoelastic applications in structural testing, fiber optics and video holography, and strain gages. Attention is given to video holography and speckle interferometry, smart structures applications to composites, thermographic stress analysis, and industrial applications of photoelasticity. Topics addressed include moire interferometry, residual stress, smart structures and structural testing, dynamic fracture, optical methods for transient events, and force sensor design and applications. Also discussed are moire and grid techniques, photoelasticity and its industrial applications, composites, transducers, optical methods in biomechanics, rock fracture related to waste isolation, and noncontacting techniques for dynamic measurements. (For individual items see A93-16602 to A93-16650)

  9. Conference of the Society for Literature and Science. Proceedings (Atlanta, Georgia, October 10-13, 1996).

    ERIC Educational Resources Information Center

    Perkowitz, Sidney, Ed.

    The papers contained in these proceedings from the 1996 Society for Literature and Science Conference are organized into sections based on theme. Some of these themes are: (1) Secularizing Enlightenment; (2) Eugenics and the Politics of Knowledge; (3) Reading the Discourses of Psychology; (4) Women and Medicine; (5) The Rhetoric of Public Health;…

  10. Future directions in studies of nuclei far from stability. [Nashville, Tennessee, Sept. 10-13, 1979

    SciTech Connect

    Hamilton, J.H.; Spejewski, E.H.; Bingham, C.R.; Zganjar, E.F.

    1980-01-01

    Individual abstracts were prepared for 27 of the papers in this volume. The remaining ten have already been cited in ERA; these papers can be located by reference to the entry CONF-790976-- in the report number index. (RWR)

  11. The Development of the Concepts of Heat and Temperature in 10-13 Year-Olds.

    ERIC Educational Resources Information Center

    Shayer, Michael; Wylam, Hugh

    1981-01-01

    Describes the development of a Piagetian demonstration group test utilized to assess 9-12 year-old students' (N=161) understanding of heat and temperature. Findings include a unitary relationship between Piagetian stages of development and levels of understanding of heat concepts. (DS)

  12. Canadian Association for University Continuing Education Conference Proceedings (Regina, Saskatchewan, Canada, June 10-13, 1992).

    ERIC Educational Resources Information Center

    Canadian Association for University Continuing Education, Ottawa (Ontario).

    This document contains the following papers: "University Continuing Educators: Entrepreneurs or Social Activists" (Phyllis Cunningham); "Ambivalent Activists, Uneasy Enterprisers--and the Search for Truth" (Milton Stern); "Our Role as Change Agents" (Timothy Pyrch, Albert A. Einsiedel); "Entrepreneurial…

  13. Educational Technology; An AED/INNOTECH Seminar. (Singapore, April 10-13, 1972.)

    ERIC Educational Resources Information Center

    Southeast Asian Ministers of Education Organization (Singapore). Regional Center for Educational Innovation and Technology.

    The full texts of the five major papers presented at the Singapore seminar comprise the body of this conference report. The seminar was jointly sponsored by the Academy for Educational Development (AED) and the Southeast Asian Ministers of Education Organization's (SEAMEO) Regional Center for Educational Innovation and Technology (INNOTECH): its…

  14. Nordic Research on Text and Discourse. NORDTEXT Symposium (Espoo, Finland, May 10-13, 1990).

    ERIC Educational Resources Information Center

    Lindeberg, Ann-Charlotte, Ed.; And Others

    Papers presented at the 1990 Symposium of the Nordic Research Group for Theoretical and Applied Text Linguistics include the following: "Success Concepts" (Enkvist); "Reconciling the Psychological with the Linguistic in Accounts of Text Comprehension" (Garrod); "Particles as Fundaments of Discourse Structuring"…

  15. Active Travel to School: Views of 10-13 Year Old Schoolchildren in Scotland

    ERIC Educational Resources Information Center

    Kirby, Joanna; Inchley, Joanna

    2009-01-01

    Purpose: The purpose of this paper is to explore the views of Scottish schoolchildren on active travel to school and their ideas about promotion strategies for school-based interventions. Design/methodology/approach: Focus group discussions were conducted with 66 students from four primary and three secondary schools. Findings: The most common…

  16. Military Curricula for Vocational & Technical Education. Orthopedic Specialist, Classroom Course 10-13.

    ERIC Educational Resources Information Center

    Brooke Army Medical Center, Fort Sam Houston, TX. Health Care Research Div.

    These military-developed curriculum materials for a course for orthopedic specialists are targeted for students from grades 11 through the adult level. The course is designed to provide a working knowledge of the application of casts, traction, and splints to orthopedic patients and the removal of these devices; a working knowledge of assisting in…

  17. ISS Update: Students Test Their Satellite Control Skills – 01.10.13

    NASA Video Gallery

    Public Affairs Officer Dan Huot conducts a phone interview with Dr. Alvar Saenz-Otero from the Massachusetts Institute of Technology (MIT). Saenz-Otero is the lead scientist for the SPHERES-Zero-Ro...

  18. Digital Mapping Techniques '09-Workshop Proceedings, Morgantown, West Virginia, May 10-13, 2009

    USGS Publications Warehouse

    Soller, David R.

    2011-01-01

    As in the previous years' meetings, the objective was to foster informal discussion and exchange of technical information, principally in order to develop more efficient methods for digital mapping, cartography, GIS analysis, and information management. At this meeting, oral and poster presentations and special discussion sessions emphasized (1) methods for creating and publishing map products (here, "publishing" includes Web-based release); (2) field data capture software and techniques, including the use of LiDAR; (3) digital cartographic techniques; (4) migration of digital maps into ArcGIS Geodatabase format; (5) analytical GIS techniques; and (6) continued development of the National Geologic Map Database.

  19. 46 CFR 39.10-13 - Submission of vapor control system designs-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... specifications for a new vessel vapor collection system must be submitted to the Marine Safety Center for... foreign flag vessel may submit certification by the classification society which classes the vessel that... in Charge, Marine Inspection, shall endorse the Certificate of Inspection for U.S. flag vessels,...

  20. American Vocational Education Research Association (AVERA) Proceedings (New Orleans, Louisiana, December 10-13, 1998).

    ERIC Educational Resources Information Center

    American Vocational Education Research Association.

    This document contains 14 research paper presentations and 5 "mini-tips" from the 1998 American Vocational Education Research Association (AVERA) annual meeting. The first section includes three papers on international and distance education: "Determining Success of Vocational Students Enrolled in Distance Education Courses"…

  1. Atmospheric chemistry of CF3CF2OCH3

    NASA Astrophysics Data System (ADS)

    Østerstrøm, Freja F.; Nielsen, Ole John; Wallington, Timothy J.

    2016-06-01

    Smog chamber Fourier transform infrared techniques were used to investigate the kinetics of the reaction of CF3CF2OCH3 with Cl atoms and OH radicals: k(Cl + CF3CF2OCH3) = (1.09 ± 0.16) × 10-13 and k(OH + CF3CF2OCH3) = (1.28 ± 0.19) × 10-14 cm3 molecule-1 s-1 in 700 Torr total pressure of N2/O2 at 296 ± 2 K. The Cl-initiated oxidation of CF3CF2OCH3 gives CF3CF2OCHO in a yield indistinguishable from 100%. An estimate of k(Cl + CF3CF2OCHO) = (1.18 ± 0.34) × 10-14 cm3 molecule-1 s-1 is provided. Based on the OH reaction rate, the atmospheric lifetime of CF3CF2OCH3 is estimated to be 5.0 years. The 100-year time horizon global warming potential of CF3CF2OCH3 is estimated to be 585. The atmospheric impact of CF3CF2OCH3 is discussed.

  2. Brucella abortus as a potential vaccine candidate: induction of interleukin-12 secretion and enhanced B7.1 and B7.2 and intercellular adhesion molecule 1 surface expression in elutriated human monocytes stimulated by heat-inactivated B. abortus.

    PubMed Central

    Zaitseva, M; Golding, H; Manischewitz, J; Webb, D; Golding, B

    1996-01-01

    Development of a vaccine which is capable of generating a strong cellular immune response associated with gamma interferon (IFN-gamma) production and cytotoxic T-cell development requires that the immunogen be capable of inducing the secretion of interleukin-12 (IL-12), which is a pivotal factor for the differentiation of Th1 or Tc1 cells. We have previously shown that the heat-inactivated gram-negative bacterium Brucella abortus can induce IFN-gamma secretion by T cells. In the present study, we demonstrate that B. abortus and lipopolysaccharide (LPS) from B. abortus can induce IL-12 p40 mRNA expression and protein secretion by human elutriated monocytes (99% pure). p40 mRNA was detected within 4 h, and p40 protein could be measured at 24 h. This induction was abrogated by anti-CD14 monoclonal antibody, suggesting that monocytes recognize B. abortus via their receptor for LPS. The biological activity of IL-12 secreted by B. abortus-stimulated monocytes was demonstrated by its ability to upregulate IFN-gamma mRNA expression in T cells separated from monocytes and B. abortus by a transwell membrane. The B. abortus-induced IL-12 also enhanced NK cytolytic activity against K562 target cells. B. abortus was shown to rapidly increase the expression of the costimulatory molecules B7.1 and B7.2 and intercellular adhesion molecule 1 on human monocytes. Together, these data indicate that B. abortus can directly activate human monocytes and provide the cytokine milieu which would direct the immune response towards Th1-Tc1 differentiation. PMID:8757841

  3. A theoretical investigation of the atmospherically important reaction between chlorine atoms and formic acid: determination of the reaction mechanism and calculation of the rate coefficient at different temperatures

    NASA Astrophysics Data System (ADS)

    Ng, Maggie; Mok, Daniel K. W.; Lee, Edmond P. F.; Dyke, John M.

    2015-07-01

    The Cl + HCOOH reaction is important in the atmosphere, as the chlorine (Cl) atom is an important oxidant, especially in the marine boundary layer, and formic acid (HCOOH) is one of the most abundant organic acids in the troposphere. The reaction surfaces of the two H abstraction channels were computed by second-order unrestricted Møller-Plesset perturbation theory (UMP2) and density functional theory (DFT) calculations. Relative electronic energies were improved to the RCCSD(T)/CBS and UCCSD(T)-F12/CBS levels. The barrier of the C-H hydrogen abstraction channel was found to be lower by about 10 kcal mol-1. Rate coefficients (k) of this channel were calculated at different temperatures at various variational transition state theory (VTST) levels including tunnelling. For single-level direct dynamics VTST calculations, the computed k (2.5 × 10-13 cm3 molecule-1 s-1) using the BMK (Boese and Martin meta hybrid) functional at the highest level (ICVT/SCT) agrees the best with experimental values at 298 K (1.8 and 2.0 × 10-13 cm3 molecule-1 s-1). For dual-level direct dynamics calculations (RCCSD(T)/CBS//MP2 MEP), an adjusted barrier height of 3.1 kcal mol-1 is required to match the ICVT/SCT k with the experimental values. The computed rate coefficients of the Cl + HCOOH reaction is reported for the first time with a temperature range of 200-1500 K. The implications of the results obtained to atmospheric chemistry are discussed.

  4. Rate coefficients for the reaction of O(1D) with the atmospherically long-lived greenhouse gases NF3, SF3CF3, CHF3, C2F6, c-C3F8, n-C5F12, and n-C6F14

    NASA Astrophysics Data System (ADS)

    Baasandorj, M.; Hall, B. D.; Burkholder, J. B.

    2012-09-01

    The contribution of atmospherically persistent (long-lived) greenhouse gases to the radiative forcing of Earth has increased over the past several decades. The impact of highly fluorinated saturated compounds, in particular perfluorinated compounds, on climate change is a concern because of their long atmospheric lifetimes, which are primarily determined by stratospheric loss processes, as well as their strong absorption in the infrared "window" region. A potentially key stratospheric loss process for these compounds is their gas-phase reaction with electronically excited oxygen atoms, O(1D). Therefore, accurate reaction rate coefficient data is desired for input to climate change models. In this work, rate coefficients, k, were measured for the reaction of O(1D) with several key long-lived greenhouse gases, namely NF3, SF5CF3, CHF3 (HFC-23), C2F6, c-C4F8, n-C5F12, and n-C6F14. Room temperature rate coefficients for the total reaction, kTot, corresponding to loss of O(1D), and reactive channel, kR, corresponding to the loss of the reactant compound, were measured for NF3 and SF5CF3 using competitive reaction and relative rate methods, respectively. kR was measured for the CHF3 reaction and improved upper-limits were determined for the perfluorinated compounds included in this study. For NF3, kTot was determined to be (2.55 ± 0.38) × 10-11 cm3 molecule-1 s-1 and kR, which was measured using CF3Cl, N2O, CF2ClCF2Cl (CFC-114), and CF3CFCl2 (CFC-114a) as reference compounds, was determined to be (2.21 ± 0.33) × 10-11 cm3 molecule-1 s-1 corresponding to a reactive branching ratio of 0.87 ± 0.13. For SF5CF3, kTot = (3.24 ± 0.50) × 10-13 cm3 molecule-1 s-1 and kR < 5.8 × 10-14 cm3 molecule-1 s-1 were measured, where kR is a factor of three lower than the current recommendation of kTot for use in atmospheric modeling. For CHF3, kR was determined to be (2.35 ± 0.35) × 10-12 cm3 molecule-1 s-1, which corresponds to a reactive channel yield of 0.26 ± 0.04, and

  5. Laboratory studies of some halogenated ethanes and ethers: Measurements of rates of reaction with OH and of infrared absorption cross-sections

    NASA Astrophysics Data System (ADS)

    Brown, Anne C.; Canosa-Mas, Carlos E.; Douglas Parr, A.; Wayne, Richard P.

    We have measured, using a conventional discharge-flow resonance-fluorescence technique, the rates of reaction between the hydroxyl radical and a series of halogenated ethanes and ethers for the temperature range 230-423 K. Our measurements gave the following Arrhenius expressions (units are cm 3 molecule -1 s -1): CF 2HCH 3 (HFC-152), 14.2 × 10 -13 exp-(1050/ T); CF 2ClCH 3 (HCFC-142b), 2.6 × 10 -13 exp-(1230/ T); CFCl 2CH 3 (HCFC-141b), 5.8 × 10 -13 exp-(1100/ T); CF 3CFH 2 (HFC-134a), 5.8 × 10 -13 exp-(1350/ T); CF 3CF 2H (HFC-125), 2.8 × 10 -13 exp-(1350/ T); CF 3CCl 2H (HCFC-123), 11.8 × 10 -13 exp-(900/ T); CF 2HOCF 2CFClH, (enflurane), 6.1 × 10 -13 exp-(1080/ T); CFH 2OCH(CF 3) 2, (sevoflurane), 15.3 × 10 -13 exp-(900/ T). In two cases, we measured rate constants only at room temperature: CF 3CClBrH (halothane), 6 × 10 -14 and CF 2HOCClHCF 3 (isoflurane), 2.1 × 10 -14. We also report the following values for the integrated absorption cross-sections of the compounds in the spectral region 800-1200 cm -1 in units of cm -2 atm -1: CF 2HCH 3, 1155; CF 2ClCH 3, 1422; CFCl 2CH 3, 1995; CF 3CFH 2, 2686; CF 3CF 2H, 1970, CF 3CCl 2H, 1411; CF 3CClBrH, 1400; CF 2HOCF 2CFClH, 4800; CF 2HOCClHCF 3, 3900; CFH 2OCH(CF 3) 2, 2550. We use our measurements to calculate ozone depletion potentials and greenhouse warming potentials relative to CFCl 3 for each compound.

  6. Rate coefficients for the gas-phase reactions of the nitrate radical with (Z)-3-hexenol (`leaf alcohol`) and its isomers

    NASA Astrophysics Data System (ADS)

    Pfrang, C.; Kasyutich, V. L.; Canosa-Mas, C. E.; Vaughan, S.; Wayne, R. P.

    2003-04-01

    The nitrate radical, NO_3, is a key species in the night-time tropospheric oxidation of a variety of volatile organic compounds (VOCs), including those emitted by living vegetation. In addition to the VOC emissions from intact plants, it is well known that wounding induces the release of a series of C_6 aldehydes and C_6 alcohols, as can be readily sensed in the odour of freshly mown grass. Large emissions of the "leaf alcohol", (Z)-3-hexenol, have been observed after wounding, during drying, and following pathogen attack, while (Z)-2-hexenol has been reported as an emission from clipped clover. Rate coefficients for the gas-phase reactions of the nitrate radical with these two isomeric compounds have been measured using the discharge-flow technique at room temperature. Because of the relatively low volatility of these compounds, it is necessary to employ low concentrations of NO_3 in order to determine the kinetics satisfactorily. To this end, we used a technique not hitherto applied in kinetic experiments on NO_3: that of off-axis continuous-wave cavity-enhanced absorption spectroscopy (CW CEAS) for the detection of NO_3, using a broadband absorption line at λ = 662 nm. A noise-equivalent detection sensitivity of 5.5 × 10^9 molecule cm-3 for the nitrate radical (Kasyutich et al., Appl. Phys. B, 2002, 75, 755--761) enabled us to work with the hexenol compounds in excess over NO_3. The rate coefficients were determined to be (2.80 ± 0.12) × 10-13 cm^3 molecule-1 s-1 and (1.36 ± 0.08) × 10-13 cm^3 molecule-1 s-1, respectively, for (Z)-3-hexenol and (Z)-2-hexenol. The rate constant for reaction with (Z)-3-hexenol lies within the combined error limits of the single measurement of the rate coefficient using relative rate methods of (2.72 ± 0.83) × 10-13 cm^3 molecule-1 s-1 (Atkinson et al., Int. J. Chem. Kinetics, 1995, 27, 941--955). However, for (Z)-3-hexenol there is some evidence for upward curvature of the second-order plot at longer contact times, and

  7. Efficiency calibration and coincidence summing correction for a large volume (946cm(3)) LaBr3(Ce) detector: GEANT4 simulations and experimental measurements.

    PubMed

    Dhibar, M; Mankad, D; Mazumdar, I; Kumar, G Anil

    2016-12-01

    The paper describes the studies on efficiency calibration and coincidence summing correction for a 3.5″×6″ cylindrical LaBr3(Ce)detector. GEANT4 simulations were made with point sources, namely, (60)Co, (94)Nb, (24)Na, (46)Sc and (22)Na. The simulated efficiencies, extracted using (60)Co, (94)Nb, (24)Na and (46)Sc that emit coincident gamma rays with same decay intensities, were corrected for coincidence summing by applying the method proposed by Vidmar et al. (2003). The method was applied, for the first time, for correcting the simulated efficiencies extracted using (22)Na that emits coincident gamma rays with different decay intensities. The measured results obtained using (60)Co and (22)Na were found to be in good agreement with simulated results.

  8. FAMOUS, faster: using parallel computing techniques to accelerate the FAMOUS/HadCM3 climate model with a focus on the radiative transfer algorithm

    NASA Astrophysics Data System (ADS)

    Hanappe, P.; Beurivé, A.; Laguzet, F.; Steels, L.; Bellouin, N.; Boucher, O.; Yamazaki, Y. H.; Aina, T.; Allen, M.

    2011-06-01

    We have optimised the atmospheric radiation algorithm of the FAMOUS climate model on several hardware platforms. The optimisation involved translating the Fortran code to C and restructuring the algorithm around the computation of a single air column. A task queue and a thread pool are used to distribute the computation to several processors. Finally, four air columns are packed together in a single data structure and computed simultaneously using Single Instruction Multiple Data operations. The modified algorithm runs more than 50 times faster on the CELL's Synergistic Processing Elements than on its main PowerPC processing element. On Intel-compatible processors, the new radiation code runs 4 times faster and on graphics processors, using OpenCL, more than 2.5 times faster, as compared to the original code. Because the radiation code takes more than 60 % of the total CPU time, FAMOUS executes more than twice as fast. Our version of the algorithm returns bit-wise identical results, which demonstrates the robustness of our approach.

  9. FAMOUS, faster: using parallel computing techniques to accelerate the FAMOUS/HadCM3 climate model with a focus on the radiative transfer algorithm

    NASA Astrophysics Data System (ADS)

    Hanappe, P.; Beurivé, A.; Laguzet, F.; Steels, L.; Bellouin, N.; Boucher, O.; Yamazaki, Y. H.; Aina, T.; Allen, M.

    2011-09-01

    We have optimised the atmospheric radiation algorithm of the FAMOUS climate model on several hardware platforms. The optimisation involved translating the Fortran code to C and restructuring the algorithm around the computation of a single air column. Instead of the existing MPI-based domain decomposition, we used a task queue and a thread pool to schedule the computation of individual columns on the available processors. Finally, four air columns are packed together in a single data structure and computed simultaneously using Single Instruction Multiple Data operations. The modified algorithm runs more than 50 times faster on the CELL's Synergistic Processing Element than on its main PowerPC processing element. On Intel-compatible processors, the new radiation code runs 4 times faster. On the tested graphics processor, using OpenCL, we find a speed-up of more than 2.5 times as compared to the original code on the main CPU. Because the radiation code takes more than 60 % of the total CPU time, FAMOUS executes more than twice as fast. Our version of the algorithm returns bit-wise identical results, which demonstrates the robustness of our approach. We estimate that this project required around two and a half man-years of work.

  10. A 0.5 cm(3) four-channel 1.1 mW wireless biosignal interface with 20 m range.

    PubMed

    Morrison, Tim; Nagaraju, Manohar; Winslow, Brent; Bernard, Amy; Otis, Brian P

    2014-02-01

    This paper presents a self-contained, single-chip biosignal monitoring system with wireless programmability and telemetry interface suitable for mainstream healthcare applications. The system consists of low-noise front end amplifiers, ADC, MICS/ISM transmitter and infrared programming capability to configure the state of the chip. An on-chip packetizer ensures easy pairing with standard off-the-shelf receivers. The chip is realized in the IBM 130 nm CMOS process with an area of 2×2 mm(2). The entire system consumes 1.07 mW from a 1.2 V supply. It weighs 0.6 g including a zinc-air battery. The system has been extensively tested in in vivo biological experiments and requires minimal human interaction or calibration.

  11. Study of the OH and Cl-initiated oxidation, IR absorption cross-section, radiative forcing, and global warming potential of four C4-hydrofluoroethers.

    PubMed

    Oyaro, Nathan; Sellevåg, Stig R; Nielsen, Claus J

    2004-11-01

    Infrared absorption cross-sections and OH and Cl reaction rate coefficients for four C4-hydrofluoroethers (CF3)2CHOCH3, CF3CH2OCH2CF3, CF3CF2CH2OCH3, and CHF2CF2CH2OCH3 are reported. Relative rate measurements at 298 K and 1013 hPa of OH and Cl reaction rate coefficients give k(OH+(CF3)2CHOCH3) = (1.27+/-0.13) x 10(-13), k(OH+CF3CH2OCH2CF3) = (1.51+/-0.24) x 10(-13), k(OH+CF3CF2CH2OCH3) = (6.42+/-0.33) x 10(-13), k(OH+CHF2CF2CH2OCH3) = (8.7 +/-0.5) x 10(-13), k(Cl+(CF3)2CHOCH3) = (8.4+/-1.3) x 10(-12), k(Cl+CF3CH2OCH2CF3) = (6.5+/-1.7) x 10(-13), k(Cl+CF3CF2CH2OCH3) = (4.0+/-0.8) x 10(-11), and k(Cl+CHF2CF2CH2OCH3) = (2.65+/-0.17) x 10(-11) cm3 molecule(-1) s(-1). The primary products of the OH and Cl reactions with the fluorinated ethers have been identified as esters, and OH and Cl reaction rate coefficients for one of these, CF3CH2OCHO, are reported: k(OH+CF3CH2OCHO) = (7.7+/-0.9) x 10(-14) and kCl+CF3CH2OCHO) = (6.3+/-1.9) x 10(-14) cm3 molecule(-1) s(-1) The rate coefficient for the Cl-atom reaction with CHF2CH2F is derived as k(Cl+CHF2CH2F) = (3.0+/-0.9) x 10(-14) cm3 molecule(-1) s(-1) at 298 K. The error limits include 3sigma from the statistical data analyses as well as the errors in the rate coefficients of the reference compounds employed. The tropospheric lifetimes of the hydrofluoroethers are estimated to be short tauOH((CF3)2CHOCH3) approximately 100 days, tauOH(CF3CH2OCH2CF3) approximately 80 days, tauOH(CF3CF2CH2OCH3) approximately 20 days, and tauOH(CHF2CF2CH2OCH3) approximately 14 days, and their global warming potentials are small compared to CFC-11.

  12. Atmospheric reactions of (H)- and (D)-fluoroalcohols with chlorine atoms.

    PubMed

    Garzón, Andrés; Moral, Mónica; Notario, Alberto; Ceacero-Vega, Antonio A; Fernández-Gómez, Manuel; Albaladejo, José

    2010-02-01

    The reactions of Cl with a series of fluoroalcohols and deuterated fluoroalcohols, CF(3)CH(2)OH (k(4)), CF(3)CH(OH)CH(3) (k(5)), CF(3)CH(OH)CF(3) (k(6)), CF(3)CH(OD)CF(3) (k(7)) and CF(3)CD(OD)CF(3) (k(8)), are investigated as a function of temperature in the range of 268-378 K by laser photolysis-resonance fluorescence. To our knowledge, only the CF(3)CH(2)OH + Cl reaction has been previously studied from a kinetic point of view. The derived Arrhenius expressions obtained using our kinetic data are: k(4) = (1.79+/-0.17) x 10(-13) exp[(410+/-26)/T], k(5) = (1.20+/-0.11) x 10(-12) exp[(394+/-14)/T], k(6) = (2.32+/-0.18) x 10(-13) exp[-(740+/-12)/T], k(7) = (6.45+/-1.87) x 10(-13) exp[-(1136+/-94)/T] and k(8) = (4.19+/-1.09) x 10(-13) exp[-(1378+/-81)/T] (in units of cm(3) molecule(-1) s(-1) and where errors are +/-sigma). Moreover, a theoretical insight into the mechanisms of these reactions is pursued through ab initio Möller-Plesset second-order perturbation treatment calculations with the 6-311G** basis set. Optimized geometries are obtained for reagents, transition states and molecular complexes appearing along the different reaction pathways. Furthermore, molecular energies are calculated at the quadratic configuration interaction with single, double and triple excitations [QCISD(T)] level to obtain an estimation of the activation energies. Finally, the rate constants are calculated through transition-state theory using Wigner's transmission coefficient in order to include the tunnelling-effect corrections.

  13. The OH-initiated atmospheric reaction mechanism and kinetics for levoglucosan emitted in biomass burning.

    PubMed

    Bai, Jing; Sun, Xiaomin; Zhang, Chenxi; Xu, Yisheng; Qi, Chuansong

    2013-11-01

    Levoglucosan is a typical molecular tracer of biomass-burning aerosols in the atmosphere. The mechanism for OH-initiated reaction with levoglucosan is studied at the level of MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p). The possible subsequent reactions in the presence of O2, NO and H2O are also taken into consideration. The study shows that the H atom abstraction from the C4-position by the OH radical is an energetically favorable pathway, and that the OH-initiated products contribute to the formation of SOA and atmospheric acidity. The kinetic calculation is performed and the rate constants are calculated over the temperature range of 200-1500 K, using the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The rate constant of levoglucosan reacting with the OH radical at 298 K is 2.21×10(-13) cm(3) molecule(-1) s(-1) and the atmospheric lifetime is 26 days ([OH]=2.0×10(6) molecule cm(-3)). The equilibrium constants both in gas phase and aqueous are computed. The free energy ΔG indicates that, the subsequent reactions tend to take place more spontaneously once the reaction occurs. This work provides a comprehensive investigation about OH-initiated atmospheric reactions with levoglucosan, which is helpful for experiment and risk assessment.

  14. Atmospheric Chemistry: Laboratory Studies of Kinetics of Important Reactions.

    NASA Astrophysics Data System (ADS)

    Smith, S. J.

    Available from UMI in association with The British Library. Requires signed TDF. This thesis describes the experiments to measure the rate constants for some reactions of the atmospherically important nitrate radical (NO_3) using the discharge-flow technique. The nitrate radical was monitored by optical absorption at lambda = 662 nm. The reactions of NO_3 with some stable organic and inorganic substrates are reported. The temperature dependences of some of the rate constants have also been determined (298 < T < 523 K). In most cases, computer simulation was used to extract the rate constant for the primary process because the time-dependent behaviour of (NO_3) was affected by secondary reactions of NO_3 with products of the primary interaction. The Arrhenius parameter in parentheses (E _{rm a}/kJ mol^ {-1}, A/cm^3 molecule ^{-1}s^ {-1} respectively) for the following reactions have been determined: ethane (37, 6.7 times 10^{-12}), ethylene (25.8, 6.3 times 10^ {-12}), CH_3OH (21.3, 1.2 times 10^ {-12}), CHCiota_3 (23.4, 8.6 times 10 ^{-13}) and HCl (27.7, 4 times 10^{-12}). The activation energies for the reactions studied between NO_3 and some alkynes are represented well by the value 25 +/- 3 kJ mol^{-1} and the corresponding pre-exponential factors (expressed as ln(10 ^{13}A/cm^3 molecule^{-1}s ^{-1}) are as follows: C_2H_2 (1.6 +/- 1.4), C_3H _4 (5.0 +/- 1.4), 1-C_4H_6 (5.8 +/- 1.0), 1-C_5 H_8 (5.7 +/- 0.6) and 1-C_6H _{10} (4.5 +/- 0.4). Some reactions were studied at room temperature _3(298 +/- 2 K) only and the rate constants found (in units of cm ^3 molecule^{ -1}s^{-1}) are: buta-1,3-diene (1.8 times 10 ^{-13}), isobutene (2.8 times 10^{-13 }), HBr (1.3 times 10 ^{-15}) and hex-2-yne (3.0 times 10^{-14 }). Non-Arrhenius behaviour was found in the reactions of NO_3 with n-butane, isobutane and propene. The empirical variation of these rate constants with temperature is well represented by the three parameter expressions:. k(T) = 1.2 times 10 ^{-46}T^{11

  15. A study of heavy precipitation events in Taiwan during 10-13 August, 1994: mesoscale model simulations

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Chen, C.-S.; Jia, Y.; Baker, D.; Lang, S.; Wetzel, P.; Lau, K.-M.; Kuo, Y.-H.; Dudhia, J.; Starr, David O'C. (Technical Monitor)

    2001-01-01

    Heavy rainfall occurred over the western side of Taiwan's complex terrain from August 10 to 13, 1994 after Typhoon Doug moved northward from the East China Sea into Taiwan and on towards the Yellow Sea. On August 10, most of the rainfall fell over sloped areas. The heaviest daily rainfall totals were in excess of 200 mm over southwestern as well as central Taiwan. However, not much rainfall occurred over northern Taiwan. The lack of rainfall over northern Taiwan also occurred on August 11, 12 and 13. The larger rainfall amounts shifted westward from the sloped areas on August 10 toward lower terrain on August 11. On August 12 and 13, most of the higher rainfall amounts were found over the coastal area in southwestern Taiwan. Notably, about 300 to 400 mm per day fell over the coastal area in southwest Taiwan on August 12 and 13. The distribution of rainfall amount was different on August 10 and 11 (termed as Case 1) compared to August 12 and 13 (termed as Case 2). The environmental situation and precipitation characteristics are analyzed using EC/TOGA data, ground-based radar data, surface rainfall patterns, surface wind data, and upper air soundings. Chen at al. (2001) also categorized the precipitation pattern into two types, propagating and quasi-stationary. For the propagating type of precipitation, rainrates increased or remained the same as systems went from the plains to mountainous regions. With the quasi-stationary type of precipitation, however, rainrates decreased as precipitation propagated across the plains and into the mountains. The focus of this study is to understand what causes the h1aher amounts of rainfall over Taiwan, and what factors influence where the higher amounts of rainfall will occur, over sloped areas or over coastal areas.

  16. Perceived milk intolerance is related to bone mineral content in 10-13 year-old female adolescents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: The purpose of this study was to determine associations among lactose maldigestion status, perceived milk intolerance (PMI), dietary calcium intake and bone mineral content in early adolescent females. Methodology: Subjects were 291 girls who participated in a sub-study of the multiple-...

  17. 1997 International Semiconductor Device Research Symposium (4th) Proceedings, Held in Charlottesville, Virginia on December 10-13, 1997

    DTIC Science & Technology

    1998-01-01

    Matagne1𔃼, Jean -Pierre Leburton1 Jacques Destine2, Guy Cantraine2 1Beckman Institute, University of Illinois at Urbana-Champaign , Urbana, IL 61820...PROCESSES R. Peter Smith, Suzanne C. Martin, Moonil Kim, Jean Bruston, Imran Mehdi, Dexter Humphrey, Michael Gaidis, Neal Erickson*, and Peter H...SEV/VSE, Feb. 1981 G. Galup-Montoro, M. Schneider, S. Acosta, R. Pinto , Proc. Brazilian Microelectronics Conference SBMICRO󈨤,1996. A. Cunha, O

  18. Life Beyond Walls. Proceedings of the National Conference on Outdoor Recreation (Ft. Collins, Colorado, November 10-13, 1988).

    ERIC Educational Resources Information Center

    Gilbert, Jim, Ed.; Bruner, Eric, Ed.

    This proceedings contains 16 papers on recreation and adventure programming, outdoor education, and outdoor leadership training. The papers are: (1) "Beyond Recreation: Our Classroom Is Wild America" (Barry Auskern); (2) "Outward Bound Leadership Model: An Exploratory Study of Leadership Variables" (Natalie L. Bartley); (3)…

  19. A Study of Heavy Precipitation Events in Taiwan During 10-13 August, 1994. Part 2; Mesoscale Model Simulations

    NASA Technical Reports Server (NTRS)

    Tao, Wei Kuo; Chen, C.-S.; Jia, Y.; Baker, D.; Lang, S.; Wetzel, P.; Lau, W. K.-M.

    2001-01-01

    Several heavy precipitation episodes occurred over Taiwan from August 10 to 13, 1994. Precipitation patterns and characteristics are quite different between the precipitation events that occurred from August 10 and I I and from August 12 and 13. In Part I (Chen et al. 2001), the environmental situation and precipitation characteristics are analyzed using the EC/TOGA data, ground-based radar data, surface rainfall patterns, surface wind data, and upper air soundings. In this study (Part II), the Penn State/NCAR Mesoscale Model (MM5) is used to study the precipitation characteristics of these heavy precipitation events. Various physical processes (schemes) developed at NASA Goddard Space Flight Center (i.e., cloud microphysics scheme, radiative transfer model, and land-soil-vegetation surface model) have recently implemented into the MM5. These physical packages are described in the paper, Two way interactive nested grids are used with horizontal resolutions of 45, 15 and 5 km. The model results indicated that Cloud physics, land surface and radiation processes generally do not change the location (horizontal distribution) of heavy precipitation. The Goddard 3-class ice scheme produced more rainfall than the 2-class scheme. The Goddard multi-broad-band radiative transfer model reduced precipitation compared to a one-broad band (emissivity) radiation model. The Goddard land-soil-vegetation surface model also reduce the rainfall compared to a simple surface model in which the surface temperature is computed from a Surface energy budget following the "force-re store" method. However, model runs including all Goddard physical processes enhanced precipitation significantly for both cases. The results from these runs are in better agreement with observations. Despite improved simulations using different physical schemes, there are still some deficiencies in the model simulations. Some potential problems are discussed. Sensitivity tests (removing either terrain or radiative processes) are performed to identify the physical processes that determine the precipitation patterns and characteristics for heavy rainfall events. These sensitivity tests indicated that terrain can play a major role in determining the exact location for both precipitation events. The terrain can also play a major role in determining the intensity of precipitation for both events. However, it has a large impact on one event but a smaller one on the other. The radiative processes are also important for determining, the precipitation patterns for one case but. not the other. The radiative processes can also effect the total rainfall for both cases to different extents.

  20. Numerical simulation of a rainfall event in Greenland during 10-13 July 2012 using Non-hydrostatic Regional Model

    NASA Astrophysics Data System (ADS)

    Hashimoto, A.; Niwano, M.; Aoki, T.

    2015-12-01

    On 12 July 2012, extensive surface melt occurred across much of the Greenland ice sheet. During this event, the expeditionary team of Snow Impurity and Glacial Microbe effects on the Arctic (SIGMA) project experienced unexpectedly heavy rainfall at their campsite on the northwestern Greenland ice sheet. We tried to reproduce the rainfall event by using the Japan Meteorological Agency Non-Hydrostatic Model (JMA-NHM) with 5-km horizontal resolution to characterize the temporal and spatial variation of the types of precipitation. The simulated results well agreed with observational data from surface stations and space-borne radar. According to the simulated results, the areas where the 1-h rainfall exceeded 0.1 mm at least once during the event accounted for 48% of the entire area of the Greenland ice sheet. In the coastal regions of western Greenland, precipitation during the event was composed of liquid hydrometeors, whereas in high-elevation regions, it was composed mainly of solid hydrometeors. Over intermediate regions, the phase of the precipitation changed temporally and spatially among liquid, solid, and a mixture of both. These phase transitions of the precipitation are very likely to affect the surface radiative properties of the ice sheet as well as the heat and mass balance at the surface of the ice sheet during the study period and afterward.

  1. Angular Resolution of an EAS Array for Gamma Ray Astronomy at Energies Greater Than 5 x 10 (13) Ev

    NASA Technical Reports Server (NTRS)

    Apte, A. R.; Gopalakrishnan, N. V.; Tonwar, S. C.; Uma, V.

    1985-01-01

    A 24 detector extensive air shower array is being operated at Ootacamund (2300 m altitude, 11.4 deg N latitude) in southern India for a study of arrival directions of showers of energies greater than 5 x 10 to the 13th power eV. Various configurations of the array of detectors have been used to estimate the accuracy in determination of arrival angle of showers with such an array. These studies show that it is possible to achieve an angular resolution of better than 2 deg with the Ooty array for search for point sources of Cosmic gamma rays at energies above 5 x 10 to the 13th power eV.

  2. EDUCAUSE 2000: Thinking IT Through. Proceedings and Post-Conference Materials (Nashville, Tennessee, October 10-13, 2000).

    ERIC Educational Resources Information Center

    EDUCAUSE, Washington, DC.

    This document presents the proceedings and post-conference materials of the annual EDUCAUSE conference. The theme of this conference was "Thinking IT Through." Conference sessions are divided into six domains: Infrastructure and Basic Services; Teaching and Learning; Managing Information Technologies and Resources; Information Systems; New…

  3. Doing Much More with Less: Implementing Operational Excellence at UC Berkeley. Research & Occasional Paper Series: CSHE.10.13

    ERIC Educational Resources Information Center

    Szeri, Andrew J.; Lyons, Richard; Huston, Peggy; Wilton, John

    2013-01-01

    Universities are undergoing historic change, from the sharp downward shift in government funding to widespread demands to document performance. At the University of California Berkeley, this led to an operational change effort unlike any the university had ever attempted, dubbed Operational Excellence. The authors describe their experiences…

  4. 40 CFR 721.10178 - Distillates (Fischer-Tropsch), hydroisomerized middle, C10-13-branched alkane fraction.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Distillates (Fischer-Tropsch... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10178 Distillates (Fischer-Tropsch... to reporting. (1) The chemical substance identified as distillates (Fischer-Tropsch),...

  5. A Brief Look at: Test Scores and the Standard Error of Measurement. E&R Report No. 10.13

    ERIC Educational Resources Information Center

    Holdzkom, David; Sumner, Brian; McMillen, Brad

    2010-01-01

    In the context of standardized testing, the standard error of measurement (SEM) is a measure of the factors other than the student's actual knowledge of the tested material that may affect the student's test score. Such factors may include distractions in the testing environment, fatigue, hunger, or even luck. This means that a student's observed…

  6. Working Knowledge: Productive Learning at Work. Proceedings [of the] International Conference (Sydney, Australia, December 10-13, 2000).

    ERIC Educational Resources Information Center

    Symes, Colin, Ed.

    This conference proceedings contains 65 presentations and 3 colloquiums from a conference that dealt with knowledge at work and knowledge that works and with how education can be successfully integrated into work and work into education. The papers are "Reading the Contexts of Complex Incidents of Adult Education Practice" (Apte);…

  7. 13th Workshop on Crystalline Silicon Solar Cell Materials and Processes: Summary Discussion, 10-13 August 2003, Vail, Colorado

    SciTech Connect

    Sopori, B.; Sinton, R.; Tan, T.; Swanson, D.

    2004-01-01

    The 13th Workshop discussion sessions addressed recent progress, critical issues in implementing new technologies, and the role of fundamental R&D in the growing PV industry. For the first time, we included a rump session, which was held on Sunday evening, August 10. This session included a panel of representatives, from various photovoltaic companies, who led a discussion of''R&D Challenges in Si PV.'' A special poster/presentation session was held on Monday evening, August 11, in which NREL/DOE subcontractors highlighted their results of research performed during the current subcontract period. This session served as a subcontract review. The workshop offered special sessions to discuss: (1) High-Efficiency Si Solar Cells, which reviewed progress made in implementing high-efficiency Si solar cell fabrication processes in the manufacturing environment; (2) Advanced Processing, as future potential approaches for making Si solar cells; (3) Commercial Issues, which addressed basic understanding behind recent processes that have been used by the PV industry; and (4) Automation and Equipment, to address capabilities and requirements of new manufacturing equipment.

  8. Complexes of lanthanides with aromatic and polyheteroatomic macrocyclic ethers. Complexes with 1,4,7,10,13,16-hexaoxacyclooctadecane

    SciTech Connect

    Martynova, T.N.; Nikulina, L.D.

    1988-02-01

    Complexes of salts of rare-earth metals with 18-crown-6 have been synthesized in media of polar organic solvents. Their physicochemical properties, as well as the influence of the nature of the rare-earth metals and the anions of the lanthanide salts on the composition and properties of the compounds obtained, have been studied. It has been established that complexes with a 1:1 metal:ligand ratio form, regardless of the synthesis conditions. The anion has an influence on the degree of hydration of the complexes obtained, as well as on their thermal stability. Thermal investigation have been carried out, and the paths of thermal degradation of the complexes have been determined.

  9. Experimental results on gamma-ray sources at E sub 0 = 10(13) - 10(14) eV

    NASA Technical Reports Server (NTRS)

    Morello, C.; Navarra, G.; Periale, L.; Vallania, P.

    1985-01-01

    The detection of very high energy gamma ray sources has been reported in the last few years by means of extensive air shower observations. The Plateau Rosa array for the registration of the arrival directions of extensive air showers has been operating since 1980 and first results on Cygnus X-3 have been reported. Here, the status of observations of Cygnus X-3 and of the Crab Pulsar are reported.

  10. Kinetics of the Gas-Phase Reaction of OH with Chlorobenzene

    NASA Astrophysics Data System (ADS)

    Bryukov, Mikhail G.; Knyazev, Vadim D.; Gehling, William M.; Dellinger, Barry

    2009-09-01

    The kinetics of the reaction of hydroxyl radicals with chlorobenzene was studied experimentally using a pulsed laser photolysis/pulsed laser induced fluorescence technique over a wide range of temperatures, 298-670 K, and at pressures between 13.33 and 39.92 kPa. The bimolecular rate constants demonstrate different behavior at low and high temperatures. At room temperature, T = 298.8 ± 1.5 K, the rate constant is equal to (6.02 ± 0.34) × 10-13 cm3 molecule-1 s-1; at high temperatures (474-670 K), the rate constant values are significantly lower and have a positive temperature dependence that can be described by an Arrhenius expression k1(T) = (1.01 ± 0.35) × 10-11 exp[(-2490 ± 170 K)/T] cm3 molecule-1 s-1. This behavior is consistent with the low-temperature reaction being dominated by reversible addition and the high-temperature reaction representing abstraction and addition-elimination channels. The potential energy surface of the reaction was studied using quantum chemical methods, and a transition state theory model was developed for all reaction channels. The temperature dependences of the high-temperature rate constants obtained in calculations using the method of isodesmic reactions for transition states (IRTS) and the CBS-QB3 method are in very good agreement with experiment, with deviations smaller than the estimated experimental uncertainties. The G3//B3LYP-based calculated rate constants are in disagreement with the experimental values. The IRTS-based model was used to provide modified Arrhenius expressions for the temperature dependences of the rate constant for the abstraction and addition-elimination (Cl replacement) channels of the reaction.

  11. Dimethyl ether oxidation at elevated temperatures (295-600 K).

    PubMed

    Rosado-Reyes, Claudette M; Francisco, Joseph S; Szente, Joseph J; Maricq, M Matti; Frøsig Østergaard, Lars

    2005-12-08

    Dimethyl ether (DME) has been proposed for use as an alternative fuel or additive in diesel engines and as a potential fuel in solid oxide fuel cells. The oxidation chemistry of DME is a key element in understanding its role in these applications. The reaction between methoxymethyl radicals and O(2) has been examined over the temperature range 295-600 K and at pressures of 20-200 Torr. This reaction has two product pathways. The first produces methoxymethyl peroxy radicals, while the second produces OH radicals and formaldehyde molecules. Real-time kinetic measurements are made by transient infrared spectroscopy to monitor the yield of three main products-formaldehyde, methyl formate, and formic acid-to determine the branching ratio for the CH(3)OCH(2) + O(2) reaction pathways. The temperature and pressure dependence of this reaction is described by a Lindemann and Arrhenius mechanism. The branching ratio is described by f = 1/(1 + A(T)[M]), where A(T) = (1.6(+2.4)(-1.0) x 10(-20)) exp((1800 +/- 400)/T) cm(3) molecule(-1). The temperature dependent rate constant of the methoxymethyl peroxy radical self-reaction is calculated from the kinetics of the formaldehyde and methyl formate product yields, k(4) = (3.0 +/- 2.1) x 10(-13) exp((700 +/- 250)/T) cm(3) molecule(-1) s(-1). The experimental and kinetics modeling results support a strong preference for the thermal decomposition of alkoxy radicals versus their reaction with O(2) under our laboratory conditions. These characteristics of DME oxidation with respect to temperature and pressure might provide insight into optimizing solid oxide fuel cell operating conditions with DME in the presence of O(2) to maximize power outputs.

  12. Reaction kinetics of Cl atoms with limonene: An experimental and theoretical study

    NASA Astrophysics Data System (ADS)

    Dash, Manas Ranjan; Rajakumar, B.

    2014-12-01

    Rate coefficients for the reaction of Cl atoms with limonene (C10H16) were measured between 278-350 K and 800 Torr of N2, using the relative rate technique, with 1,3-butadiene (C4H6), n-nonane (C9H20), and 1-pentene (C5H10) as reference compounds. Cl atoms were generated by UV photolysis of oxalyl chloride ((COCl)2) at 254 nm. A gas chromatograph equipped with a flame ionization detector (GC-FID) was used for quantitative analysis of the organics. The rate coefficient for the reaction of Cl atoms with limonene at 298 K was measured to be (8.65 ± 2.44) × 10-10 cm3 molecule-1 s-1. The rate coefficient is an average value of the measurements, with two standard deviations as the quoted error, including uncertainties in the reference rate coefficients. The kinetic data obtained over the temperature range of 278-350 K were used to derive the following Arrhenius expression: k(T) = (9.75 ± 4.1) × 10-11 exp[(655 ± 133)/T] cm3 molecule-1 s-1. Theoretical kinetic calculations were also performed for the title reaction using conventional transition state theory (CTST) in combination with G3(MP2) theory between 275 and 400 K. The kinetic data obtained over the temperature range of 275-400 K were used to derive an Arrhenius expression: k(T) = (7.92 ± 0.82) × 10-13 exp[(2310 ± 34)/T] cm3 molecule-1 s-1. The addition channels contributes maximum to the total reaction and H-abstraction channels can be neglected in the range of studied pressures. The Atmospheric lifetime (τ) of limonene due to its reaction with Cl atoms was estimated and concluded that the reaction with chlorine atoms can be an effective tropospheric loss pathway in the marine boundary layer and in coastal urban areas.

  13. Kinetic study of OH radical reactions with CF3CCl=CCl2, CF3CCl=CClCF3 and CF3CF=CFCF3.

    PubMed

    Cometto, Pablo M; Taccone, Raúl A; Nieto, Jorge D; Dalmasso, Pablo R; Lane, Silvia I

    2010-12-17

    The relative rate technique has been used to determine the rate constants of the reactions of OH radicals with CF(3)CCl=CCl(2) (k(1)), CF(3)CCl=CClCF(3) (k(2)) and CF(3)CF=CFCF(3) (k(3)). Experiments were carried out at (298±2) K and atmospheric pressure using ultrapure nitrogen as gas bath. The decay rates of the organic species were measured relative to those of ethane, methanol, acetone, chloroethane and 2-butanone. The following rate constants were derived in units of cm(3) molecule(-1) s(-1): k(1)= (10±1)×10(-13), k(2)=(2.1±0.2)×10(-13) and k(3)=(3.7±0.2)×10(-13). This is the first experimental determination of k(1) and k(2). The rate constants obtained are compared with previous literature data to establish reactivity trends and are used to estimate the atmospheric lifetimes of the studied perhaloalkenes. From the calculated lifetimes, using an average global concentration of hydroxyl radicals, the atmospheric loss of these compounds by the OH-initiated oxidation was determined. Also, estimations have been made of the ozone depletion potential (ODP), the radiative forcing efficiency (RE), the halocarbon global warming potential (HGWP) and the global warming potential (GWP) of the perhaloalkenes. The approximate nature of these values is stressed considering that these are short-lived compounds for which these atmospheric parameters may vary according to latitude and season.

  14. Structural and mechanistic insights into the activation of Stromal interaction molecule 1 (STIM1).

    PubMed

    Yang, Xue; Jin, Hao; Cai, Xiangyu; Li, Siwei; Shen, Yuequan

    2012-04-10

    Calcium influx through the Ca(2+) release-activated Ca(2+) (CRAC) channel is an essential process in many types of cells. Upon store depletion, the calcium sensor in the endoplasmic reticulum, STIM1, activates Orai1, a CRAC channel in the plasma membrane. We have determined the structures of SOAR from Homo sapiens (hSOAR), which is part of STIM1 and is capable of constitutively activating Orai1, and the entire coiled coil region of STIM1 from Caenorhabditis elegans (ceSTIM1-CCR) in an inactive state. Our studies reveal that the formation of a SOAR dimer is necessary to activate the Orai1 channel. Mutations that disrupt SOAR dimerization or remove the cluster of positive residues abolish STIM1 activation of Orai1. We identified a possible inhibitory helix within the structure of ceSTIM1-CCR that tightly interacts with SOAR. Functional studies suggest that the inhibitory helix may keep the C-terminus of STIM1 in an inactive state. Our data allowed us to propose a model for STIM1 activation.

  15. Hyperhyaluronanemia in alcoholic hepatitis is associated with increased levels of circulating soluble intercellular adhesion molecule-1.

    PubMed

    Hill, D B; Deaciuc, I V; McClain, C J

    1998-09-01

    The purpose of this study was to evaluate the role of the sinusoidal endothelial cell (SEC) during the clinical course of alcoholic hepatitis. Twenty consenting patients (mean age: 49.4 +/- 11.0 years) with moderate or severe hepatitis were studied. The patients were selected and characterized according to their history of drinking and laboratory profile, including serum aminotransferases, bilirubin, total white blood cell and neutrophil count, and prothrombin times. C-reactive protein and interleukin-6 were also measured as markers of the hepatic acute phase response. A marker of the SEC functional state, the circulating level of hyaluronan, was measured in parallel with the circulating levels of soluble intercellular adhesion molecule (sICAM)-1 over a 6-month observation period. All patients were hospitalized for the first month and encouraged to abstain from drinking for the duration of the study. The initial increased levels of both hyaluronan (542 +/- 32 ng x ml(-1) serum) and sICAM-1 (488 +/- 70 ng x ml(-1) serum), gradually fell during the 6-month observation period, eventually reaching values close to those seen in healthy subjects. A positive correlation was obtained between changes in these two markers of SEC function/activation on the one hand, and between these two tests and bilirubin, on the other hand. These data indicate that abnormalities of SEC function/activation, as reflected by serum hyaluronan and siCAM-1, are prominent in alcoholic hepatitis, and these alterations improve within relatively short periods of time after cessation of alcohol consumption.

  16. Nonperturbative quantum and classical calculations of multiphoton vibrational excitation and dissociation of Morse molecules^1

    NASA Astrophysics Data System (ADS)

    Dimitriou, K. I.; Mercouris, Th.; Constantoudis, V.; Komninos, Y.; Nicolaides, C. A.

    2006-05-01

    The multiphoton vibrational excitation and dissociation of Morse molecules have been computed nonperturbatively using Hamilton's and Schrφdinger's time-dependent equations, for a range of laser pulse parameters. The time-dependent Schrφdinger equation is solved by the state-specific expansion approach [e.g.,1]. For its solution, emphasis has been given on the inclusion of the continuous spectrum, whose contribution to the multiphoton probabilities for resonance excitation to a number of excited discrete states as well as to dissociation has been examined as a function of laser intensity, frequency and pulse duration. An analysis of possible quantal-classical correspondences for this system is being carried out. We note that distinct features exist from previous classical calculations [2]. For example, the dependence on the laser frequency gives rise to an asymmetry around the red-shifted frequency corresponding to the maximum probability. [1] Th. Mercouris, I. D. Petsalakis and C. A. Nicolaides, J. Phys. B 27, L519 (1994). [2] V. Constantoudis and C. A. Nicolaides, Phys. Rev. E 64, 562112 (2001). ^1This work was supported by the program 'Pythagoras' which is co - funded by the European Social Fund (75%) and Natl. Resources (25%). ^2Physics Department, National Technical University, Athens, Greece.^3Theoretical and Physical Chemistry Institute, Hellenic Research Foundation, Athens, Greece.

  17. Intercellular adhesion molecule-1 (ICAM-1) deficiency protects mice against severe forms of experimentally induced colitis

    PubMed Central

    Bendjelloul, F; Malý, P; Mandys, V; Jirkovská, M; Prokešová, L; Tučková, L; Tlaskalová-Hogenová, H

    2000-01-01

    ICAM-1 (CD54), the ligand for LFA-1 and Mac-1, is up-regulated during inflammatory reaction on the activated vascular endothelium. To determine its role in intestinal inflammation, we induced acute experimental colitis in mice with a deleted ICAM-1 gene, by feeding them with 3% dextran sodium sulphate (DSS) in drinking water for 7 days. Chronic colitis was elicited by DSS similarly, followed by 2 weeks with water. In the acute phase of inflammation, ICAM-1-deficient mice exhibited a significantly lower mortality rate (5%) than control C57Bl/6J mice (35%). Control animals, but not the ICAM-1-deficient mice, exhibited diarrhoea and rectal bleeding. Histological examination of large-bowel samples evaluated the intensity of inflammatory changes, and type and extent of mucosal lesions. In the acute phase, 33.3% of samples from ICAM-1-deficient mice exhibited mucosal defects (flat and fissural ulcers), predominantly mild to moderate inflammatory infiltrate within the lamina propria mucosae and lower grades of mucosal lesions. Much stronger inflammatory changes were present in control animals, flat ulcers (sometimes multiple) and fissural ulcers being observed in 62.5% of samples. Mucosal inflammatory infiltrate was moderate to severe, typically with higher grades of mucosal lesions. In chronic colitis, smaller inflammatory changes were found in the large bowel. The two mouse strains differed, the chronic colitis being accompanied by an increased serum level of anti-epithelial IgA autoantibodies in C57Bl/6 control mice but not in ICAM-1-deficient mice. These findings provide direct evidence of the participation of ICAM-1 molecule in the development of experimentally induced intestinal inflammation. PMID:10606964

  18. Functional role of stromal interaction molecule 1 (STIM1) in vascular smooth muscle cells

    SciTech Connect

    Takahashi, Yoichiro; Watanabe, Hiroyuki; Murakami, Manabu; Ono, Kyoichi; Munehisa, Yoshiko; Koyama, Takashi; Nobori, Kiyoshi; Iijima, Toshihiko; Ito, Hiroshi

    2007-10-05

    We investigated the functional role of STIM1, a Ca{sup 2+} sensor in the endoplasmic reticulum (ER) that regulates store-operated Ca{sup 2+} entry (SOCE), in vascular smooth muscle cells (VSMCs). STIM1 was mainly localized at the ER and plasma membrane. The knockdown of STIM1 expression by small interfering (si) RNA drastically decreased SOCE. In contrast, an EF-hand mutant of STIM1, STIM1{sup E87A}, produced a marked increase in SOCE, which was abolished by co-transfection with siRNA to transient receptor potential canonical 1 (TRPC1). In addition, transfection with siRNA against STIM1 suppressed phosphorylation of cAMP-responsive element binding protein (CREB) and cell growth. These results suggest that STIM1 is an essential component of SOCE and that it is involved in VSMC proliferation.

  19. PRIMING EFFECT OF HOMOCYSTEINE ON INDUCIBLE VASCULAR CELL ADHESION MOLECULE-1 EXPRESSION IN ENDOTHELIAL CELLS

    PubMed Central

    Séguin, Chantal; Abid, Md. Ruhul; Spokes, Katherine C.; Schoots, Ivo G; Brkovic, Alexandre; Sirois, Martin G.; Aird, William C.

    2017-01-01

    Hyperhomocysteinemia is an independent risk factor for the development of atherosclerosis, as well as for arterial and venous thrombosis. However, the mechanisms through which elevated circulating levels of homocysteine cause vascular injury and promote thrombosis remain unclear. Here, we tested the hypothesis that homocysteine (Hcy) sensitizes endothelial cells to the effect of inflammatory mediators. Human umbilical vein endothelial cells (HUVEC) were incubated with Hcy 1.0 mM for varying time points, and then treated in the absence or presence of 1.5 U/ml thrombin or 10 ng/ml lipopolysaccharide (LPS). Hcy alone had no effect on the expression of vascular cell adhesion molecule (VCAM)-1. However, Hcy enhanced thrombin- and LPS-mediated induction of VCAM-1 mRNA and protein levels. Consistent with these results, pretreatment of HUVEC with Hcy resulted in a two-fold increase in LSP-mediated induction of leukocyte adhesion. The latter effect was significantly inhibited by anti-VCAM-1 antibodies. Together, these findings suggest that Hcy sensitizes HUVEC to the effect of inflammatory mediators thrombin and LPS, at least in part through VCAM-1 expression and function. PMID:18406566

  20. De novo expression of intercellular adhesion molecule 1 (ICAM-1, CD54) in pancreas cancer.

    PubMed

    Schwaeble, W; Kerlin, M; Meyer zum Büschenfelde, K H; Dippold, W

    1993-01-21

    We examined the expression of intercellular--adhesion molecule-I (ICAM-I, CD54) in 6 surgically removed pancreatic tumors and 8 pancreatic tumor cell lines. Immunohistochemistry revealed a varying percentage of ICAM-I-positive pancreas tumor cells, while normal pancreatic tissue (except for slight reactivity of endothelial cells) was not stained. The presence of the ICAM-I molecule on the cell surface and the expression of ICAM-I mRNA were investigated for 8 different pancreatic tumor cell lines. Three of these (Capan-I, Capan-2, QGP-I) expressed ICAM-I constitutively. In 4 of the ICAM-I-negative pancreas cancer cell lines, it was possible to induce a remarkable expression of ICAM-I by incubating the cells in the presence of inflammatory cytokines, whereas one cell line, 818-4, remained ICAM-I-negative. The responsiveness to either IFN-gamma, TNF-alpha, or IL-I beta treatment was shown to vary from cell line to cell line, indicating complex mechanisms that regulate the expression of ICAM-I at both, the transcriptional and the post-transcriptional level. Interestingly, ICAM-I is shed by pancreatic tumor cells, since soluble sICAM-I was detected in the cell-culture supernatants. In comparison with normal sera, the mean level of sICAM-I in sera of patients with pancreas carcinoma is elevated 2-fold.

  1. Expression of HLA-ABC, HLA-DR and intercellular adhesion molecule-1 in oesophageal carcinoma.

    PubMed Central

    Rockett, J C; Darnton, S J; Crocker, J; Matthews, H R; Morris, A G

    1995-01-01

    AIM--To examine the expression of HLA-ABC and HLA-DR major histocompatibility (MHC) antigens and intercellular adhesion molecule (ICAM)-1 in normal, inflamed, metaplastic, and neoplastic oesophageal tissue and in freshly disaggregated tumours. METHODS--Sequential sections of frozen tissue and cytospins of freshly disaggregated tumour were stained using the ABC peroxidase system and monoclonal antibodies specific for HLA-ABC, HLA-DR and ICAM-1. RESULTS--Normal oesophageal tissue showed positive staining for HLA-ABC in the basal layers of the oesophageal squamous epithelium and on the epithelial cells of the submucosal oesophageal glands. HLA-DR and ICAM-1 were not detected in either of these cell types. In 20 of 37 (54%) carcinomas HLA-ABC was expressed weakly, with heterogeneous expression in nine (24%). Two tumours showed strong expression of HLA-ABC, but 15 of 37 (41%) were negative. HLA-DR and ICAM-1 were expressed weakly in six of 37 (16%) carcinomas without correlation with each other or with the expression of HLA-ABC. CONCLUSIONS--HLA-ABC is absent from a high proportion of oesophageal carcinomas (41%) and is otherwise variably and weakly expressed with strong expression in only a small fraction (3%). In other carcinomas there is a higher level of HLA-ABC expression. This discrepancy may partly explain the aggressive nature of oesophageal carcinomas. HLA-DR and ICAM-1 are not normally expressed on those cells from which oesophageal carcinomas are thought to arise. The limited expression found here could suggest a partial or inhibited immune response against oesophageal carcinoma. In vivo repressive factors may be involved. Images PMID:7665697

  2. Novel Vein Patterns in Arabidopsis Induced by Small Molecules1[OPEN

    PubMed Central

    Cutler, Sean

    2016-01-01

    The critical role of veins in transporting water, nutrients, and signals suggests that some key regulators of vein formation may be genetically redundant and, thus, undetectable by forward genetic screens. To identify such regulators, we screened more than 5000 structurally diverse small molecules for compounds that alter Arabidopsis (Arabidopsis thaliana) leaf vein patterns. Many compound-induced phenotypes were observed, including vein networks with an open reticulum; decreased or increased vein number and thickness; and misaligned, misshapen, or nonpolar vascular cells. Further characterization of several individual active compounds suggests that their targets include hormone cross talk, hormone-dependent transcription, and PIN-FORMED trafficking. PMID:26574596

  3. An essential approach to the architecture of diatomic molecules: 1. Basic theory

    NASA Astrophysics Data System (ADS)

    Yarman, T.

    2004-11-01

    We consider the quantum-mechanical description of a diatomic molecule of electronic mass m 0 e , internuclear distance R 0, and total electronic energy E 0 e . We apply to it the Born-Oppenheimer approximation, together with the relation E 0 e m 0 e R {0/2} ˜ h 2 (which we established previously), written for the electronic description (with fixed nuclei). Our approach yields an essential relationship for T 0, the classical vibration period, at the total electronic energy E 0 e ; i.e., T_0 = [4π ^2 /(sqrt {n_1 n_2 } h)]sqrt {gmathcal{M}_0 m_e } R_0^2. Here, ℳ0 is the reduced mass of the nuclei; m e is the mass of the electron; g is a dimensionless and relativistically invariant coefficient, roughly around unity (this quantity is associated with the particular electronic structure under consideration; thus, it remains practically the same for bonds bearing similar electronic configurations); and n 1 and n 2 are the principal quantum numbers of electrons making up the bond(s) of the diatomic molecule in hand; because of quantum defects, they are not integer numbers. The above relationship holds generally, although the quantum numbers n 1 and n 2 need to be refined. This task is undertaken in our next article, yielding a whole new systematization regarding all diatomic molecules.

  4. Experimental Cerebral Malaria Develops Independently of Endothelial Expression of Intercellular Adhesion Molecule-1 (ICAM-1)*

    PubMed Central

    Ramos, Theresa N.; Bullard, Daniel C.; Darley, Meghan M.; McDonald, Kristin; Crawford, David F.; Barnum, Scott R.

    2013-01-01

    Cerebral malaria (CM) is a severe clinical complication of Plasmodium falciparum malaria infection and is characterized by a high fatality rate and neurological damage. Sequestration of parasite-infected red blood cells in brain microvasculature utilizes host- and parasite-derived adhesion molecules and is an important factor in the development of CM. ICAM-1, an alternatively spliced adhesion molecule, is believed to be critical on endothelial cells for infected red blood cell sequestration in CM. Using ICAM-1 mutant mice, we found that the full-length ICAM-1 isoform is not required for development of murine experimental CM (ECM) and that ECM phenotype varies with the combination of ICAM-1 isoforms expressed. Furthermore, we observed development of ECM in transgenic mice expressing ICAM-1 only on leukocytes, indicating that endothelial cell expression of this adhesion molecule is not required for disease pathogenesis. We propose that ICAM-1-dependent cellular aggregation, independent of ICAM-1 expression on the cerebral microvasculature, contributes to ECM. PMID:23493396

  5. Experimental cerebral malaria develops independently of endothelial expression of intercellular adhesion molecule-1 (icam-1).

    PubMed

    Ramos, Theresa N; Bullard, Daniel C; Darley, Meghan M; McDonald, Kristin; Crawford, David F; Barnum, Scott R

    2013-04-19

    Cerebral malaria (CM) is a severe clinical complication of Plasmodium falciparum malaria infection and is characterized by a high fatality rate and neurological damage. Sequestration of parasite-infected red blood cells in brain microvasculature utilizes host- and parasite-derived adhesion molecules and is an important factor in the development of CM. ICAM-1, an alternatively spliced adhesion molecule, is believed to be critical on endothelial cells for infected red blood cell sequestration in CM. Using ICAM-1 mutant mice, we found that the full-length ICAM-1 isoform is not required for development of murine experimental CM (ECM) and that ECM phenotype varies with the combination of ICAM-1 isoforms expressed. Furthermore, we observed development of ECM in transgenic mice expressing ICAM-1 only on leukocytes, indicating that endothelial cell expression of this adhesion molecule is not required for disease pathogenesis. We propose that ICAM-1-dependent cellular aggregation, independent of ICAM-1 expression on the cerebral microvasculature, contributes to ECM.

  6. Ab initio studies of ClOx reactions. IV. Kinetics and mechanism for the self-reaction of ClO radicals

    NASA Astrophysics Data System (ADS)

    Zhu, R. S.; Lin, M. C.

    2003-03-01

    The self-reaction of ClO radicals has been investigated by ab initio molecular orbital and variational transition state theory calculations. Both singlet and triplet potential energy surfaces were predicted by the modified Gaussian-2 method. The reaction was shown to take place mainly over the singlet surface by forming ClOOCl (k1) and ClOClO (k1'). These association processes were found to be strongly pressure dependent and the predicted total rate constants are in good agreement with the experimental data. The predicted second- and third-order rate constants for formation of ClOOCl and ClOClO can be expressed, respectively, in units of cm3 molecule-1 s-1 and cm6 molecule-2 s-1 by k1∞=1.6×10-9T-0.67 exp(-64/T), k1'∞=6.4×10-9T-0.78 exp(-76/T), and k10=8.31×10-20T-4.96 exp(-336/T), k1'0=1.72×10-14T-6.99 exp(-926/T) in the temperature range 180-500 K for N2 as the third body. The observed T, P-dependent data could be best accounted for with the heat of formation of ClOOCl, ΔfH0o(ClOOCl)=29.4±1 kcal/mol. The formation of Cl2+O2 (2), Cl+ClOO (3), and Cl+OClO (4) products have been confirmed, with the predicted pressure-independent rate constants: k2=1.09×10-13T0.66 exp(-1892/T); k3=1.36×10-13T0.77exp(-2168/T); k4=6.26×10-11T0.005 exp(-2896/T), respectively, in units of cm3 molecule-1 s-1, covering the temperature range 200-1500 K. These results are also in reasonable agreement with existing experimental kinetic data.

  7. Kinetics of elementary steps in the reactions of atomic bromine with isoprene and 1,3-butadiene under atmospheric conditions.

    PubMed

    Laine, Patrick L; Sohn, Yoon S; Nicovich, J Michael; McKee, Michael L; Wine, Paul H

    2012-06-21

    adduct formation is observed allows the rate coefficients for the Br-Iso + O(2) (k(2)) and Br-Bu + O(2) (k(4)) reactions to be determined. At 298 K, we find that k(2) = (3.2 ± 1.0) × 10(-13) cm(3) molecule(-1) s(-1) independent of pressure (uncertainty is 2σ, precision only; pressure range is 25-700 Torr) whereas k(4) increases from 3.2 to 4.7 × 10(-13) cm(3) molecule(-1) s(-1) as the pressure increases from 25 to 700 Torr. Our results suggest that under atmospheric conditions, Br-Iso and Br-Bu react with O(2) to produce peroxy radicals considerably more rapidly than they undergo unimolecular decomposition. Hence, the very fast addition reactions appear to control the rates of Br-initiated formation of Br-Iso-OO and Br-Bu-OO radicals under atmospheric conditions. The peroxy radicals are relatively weakly bound, so conjugated diene regeneration via unimolecular decomposition reactions, though unimportant on the time scale of the reported experiments (milliseconds), is likely to compete effectively with bimolecular reactions of peroxy radicals under relatively warm atmospheric conditions as well as in 298 K competitive kinetics experiments carried out in large chambers.

  8. Kinetics and products study of the reaction of BrO radicals with gaseous mercury

    NASA Astrophysics Data System (ADS)

    Raofie, F.; Ariya, P. A.

    2003-05-01

    Bro reactions of elemental mercury was as a major candidate for near complete depletion of elemental mercury in polar region. The kinetics of the reaction between BrO radicals with gaseous mercury was identified using relative rate method by Gas Chromatography with Mass spectroscopic Detection (GC-MS) at room temperature (298±1 K) and at atmospheric pressure 760 ± 1 Torr in the N_2 diluent. Propane, DMS and butane were used as reference molecules. The upper and lower limits rate constant for reaction of Hg^0 with BrO was estimated to be 1.0 × 10^{-13} and 1.0 × 10^{15} cm^3 molecules^{-1} s^{-1}, respectively. BrO radicals were produced from the photolysis of bromine and dibromomethane in presence of ozone and detected by MS at m/e = 95 or 97. Ozone was produced in a Silent discharged generator. Reaction products were identified using direct mass spectrometer with chemical ionization ion source.

  9. Heterogeneous oxidation of folpet and dimethomorph by OH radicals: A kinetic and mechanistic study

    NASA Astrophysics Data System (ADS)

    Al Rashidi, M.; Chakir, A.; Roth, E.

    2014-01-01

    This study investigates the heterogeneous OH oxidation of folpet and dimethomorph, two fungicides identified in the atmosphere of the Champagne-Ardenne region. Kinetic experiments were conducted in the relative mode, using terbuthylazine as a reference compound. The experimental method employed makes use of a simulation chamber coupled to a GC/MS analytical system. Meanwhile, the identification of (4-chlorophenyl)(3,4-dimethoxyphenyl)methanone (CPMPM), a degradation product of the OH oxidation of dimethomorph, is achieved using SPME/GC/MS. Moreover, a degradation mechanism of dimethomorph is proposed, and the heterogeneous OH reactivity of CPMPM is evaluated. The obtained OH reaction rate constants (cm3 molecule-1 s-1) are: kZ-dimethomorph = (2.0 ± 1.2) 10-14, kE-dimethomorph = (1.7 ± 1.2) 10-14, kFolpet = (1.6 ± 0.9) 10-13 and kCPMPM = (1.9 ± 1.0) 10-12. The implicated tropospheric life-times are up to 2 months, which shows that the investigated pesticides are relatively persistent towards oxidation removal processes. CPMPM, the identified product of OH oxidation of dimethomorph, is less persistent with a life time of only 6 days relative to heterogeneous oxidation by OH radicals.

  10. Kinetics of HO2 + HO2 -> H2O2 + O2: Implications for Stratospheric H2O2

    NASA Astrophysics Data System (ADS)

    Christensen, L. E.; Okumura, M.; Sander, S. P.; Salawitch, R. J.; Toon, G. C.; Sen, B.; Blavier, J.-F.; Jucks, K. W.

    2002-05-01

    The reaction HO2 + HO2 -> H2O2 + O2(1) has been studied at 100 Torr and 222 K to 295 K. Experiments employing photolysis of Cl2/CH3OH/O2/N2 and F2/H2/O2/N2 gas mixtures to produce HO2 confirmed that methanol enhanced the observed reaction rate. At 100 Torr, zero methanol, k1 = (8.8 +/- 0.9) 10-13 × exp[(210 +/- 26)/T] cm3 molecule-1 s-1 (2σ uncertainties), which agrees with current recommendations at 295 K but is nearly 2 times slower at 231 K. The general expression for k1, which includes the dependence on bath gas density, is k1 = (1.5 +/- 0.2) × 10-12 × exp[(19 +/- 31)/T] + 1.7 × 10-33 × [M] × exp[1000/T], where the second term is taken from the JPL00-3 recommendation. The revised rate largely accounts for a discrepancy between modeled and measured [H2O2] in the lower to middle stratosphere.

  11. Influence of the heterogeneous reaction HCl + HOCl on an ozone hole model with hydrocarbon additions

    NASA Astrophysics Data System (ADS)

    Elliott, Scott; Cicerone, Ralph J.; Turco, Richard P.; Drdla, Katja; Tabazadeh, Azadeh

    1994-02-01

    Injection of ethane or propane has been suggested as a means for reducing ozone loss within the Antarctic vortex because alkanes can convert active chlorine radicals into hydrochloric acid. In kinetic models of vortex chemistry including as heterogeneous processes only the hydrolysis and HCl reactions of ClONO2 and N2O5, parts per billion by volume levels of the light alkanes counteract ozone depletion by sequestering chlorine atoms. Introduction of the surface reaction of HCl with HOCl causes ethane to deepen baseline ozone holes and generally works to impede any mitigation by hydrocarbons. The increased depletion occurs because HCl + HOCl can be driven by HOx radicals released during organic oxidation. Following initial hydrogen abstraction by chlorine, alkane breakdown leads to a net hydrochloric acid activation as the remaining hydrogen atoms enter the photochemical system. Lowering the rate constant for reactions of organic peroxy radicals with ClO to 10-13 cm3 molecule-1 s-1 does not alter results, and the major conclusions are insensitive to the timing of the ethane additions. Ignoring the organic peroxy radical plus ClO reactions entirely restores remediation capabilities by allowing HOx removal independent of HCl. Remediation also returns if early evaporation of polar stratospheric clouds leaves hydrogen atoms trapped in aldehyde intermediates, but real ozone losses are small in such cases.

  12. Theoretical investigation of the hydrogen abstraction reaction of the OH radical with CH2FCH2F (HFC-152): a dual-level direct dynamics study.

    PubMed

    Taghikhani, Mahdi; Parsafar, G A

    2007-08-23

    The hydrogen abstraction reaction of the OH radical with CH(2)FCH(2)F (HFC-152) is studied theoretically over the 150-3000 K temperature range. In this study, the two most recently developed hybrid density functional theories, namely, BB1K and MPWB1K, are applied, and their efficiency in reaction dynamics calculation is discussed. The BB1K/6-31+G(d,p) method gives the best result for the potential energy surface (PES) calculations, including barrier heights, reaction path information (the first and second derivatives of PES), geometry of transition state structures, and even weak hydrogen bond orientations. The rate constants were obtained by the dual-level direct dynamics with the interpolated single-point energy method (VTST-ISPE) using the BB1K/MG3S//BB1K/6-31+G(d,p) quantum model. The canonical variational transition state theory (CVT) with the small-curvature tunneling correction methods are used to calculate the rate constants in comparison to the experimental data. The total rate constant and its temperature dependency in the form of a fitted three-parameter Arrhenius expression is k(T) = 5.4 x 10(-13)(T/298)3.13 exp{-322/T} cm3 molecule(-1) s(-1). A significant variational effect, which is not common generally for hydrogen-transfer reactions, is reported and analyzed.

  13. Theoretical perspectives on the mechanism and kinetics of the OH radical-initiated gas-phase oxidation of PCB126 in the atmosphere.

    PubMed

    Dang, Juan; Shi, Xiangli; Zhang, Qingzhu; Wang, Wenxing

    2015-06-01

    Polychlorinated biphenyls (PCBs) primarily exist in the gas phase in air and may undergo atmospheric oxidation degradations, particularly the oxidation reaction initiated by OH radicals. In this work, the mechanism of the OH radical-initiated atmospheric oxidation of the most toxic PCB congener 3,3',4,4',5-pentachlorobiphenyl (PCB126) was investigated by using quantum chemistry methods. The rate constants of the crucial elementary reactions were estimated by the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The oxidation products of the reaction of PCB126 with OH radicals include 3,3',4,4',5-pentachlorobiphenyl-ols, chlorophenols, 2,3,4,7,8-pentachlorodibenzofuran, 2,3,4,6,7-pentachlorodibenzofuran, dialdehydes, 3,3',4,4',5-pentachloro-5'-nitro-biphenyl, and 4,5-dichloro-2-nitrophenol. Particularly, the formation of polychlorinated dibenzofurans (PCDFs) from the atmospheric oxidation of PCBs is revealed for the first time. The overall rate constant of the OH addition reaction is 2.52×10(-13)cm(3)molecule(-1)s(-1) at 298K and 1atm. The atmospheric lifetime of PCB126 determined by OH radicals is about 47.08days which indicates that PCB126 can be transported long distances from local to global scales.

  14. Kinetic studies of the reactions of O2(b 1sigma(g)+) with several atmospheric molecules.

    PubMed

    Dunlea, Edward J; Talukdar, Ranajit K; Ravishankara, A R

    2005-05-05

    Thermal rate coefficients for the removal (reaction + quenching) of O2(1sigma(g)+) by collision with several atmospheric molecules were determined to be as follows: O3, k3(210-370 K) = (3.63 +/- 0.86) x 10(-11) exp((-115 +/- 66)/T); H2O, k4(250-370 K) = (4.52 +/- 2.14) x 10(-12) exp((89 +/- 210)/T); N2, k5(210-370 K) = (2.03 +/- 0.30) x 10(-15) exp((37 +/- 40)/T); CO2, k6(298 K) = (3.39 +/- 0.36) x 10(-13); CH4, k7(298 K) = (1.08 +/- 0.11) x 10(-13); CO, k8(298 K) = (3.74 +/- 0.87) x 10(-15); all units in cm3 molecule(-1) s(-1). O2(1sigma(g)+) was produced by directly exciting ground-state O2(3sigma(g)-) with a 762 nm pulsed dye laser. The reaction of O2(1sigma(g)+) with O3 was used to produce O(3P), and temporal profiles of O(3P) were measured using VUV atomic resonance fluorescence in the presence of the reactant to determine the rate coefficients for removal of O2(1sigma(g)+). Our results are compared with previous values, where available, and the overall trend in the O2(1sigma(g)+) removal rate coefficients and the atmospheric implications of these rate coefficients are discussed. Additionally, an upper limit for the branching ratio of O2(1sigma(g)+) + CO to give O(3P) + CO2 was determined to be < or = 0.2% and this reaction channel is shown to be of negligible importance in the atmosphere.

  15. Laser induced fluorescence studies of iodine oxide chemistry. Part II. The reactions of IO with CH3O2, CF3O2 and O3.

    PubMed

    Dillon, Terry J; Tucceri, María E; Crowley, John N

    2006-11-28

    The technique of pulsed laser photolysis was coupled to laser induced fluorescence detection of iodine oxide (IO) to measure rate coefficients, k for the reactions IO + CH(3)O(2)--> products (R1, 30-318 Torr N(2)), IO + CF(3)O(2)--> products (R2, 70-80 Torr N(2)), and IO + O(3)--> OIO + O(2) (R3a). Values of k(1) = (2 +/- 1) x 10(-12) cm(3) molecule(-1) s(-1), k(2) = (3.6 +/- 0.8) x 10(-11) cm(3) molecule(-1) s(-1), and k(3a) <5 x 10(-16) cm(3) molecule(-1) s(-1) were obtained at T = 298 K. In the course of this work, the product yield of IO from the reaction of CH(3)O(2) with I was determined to be close to zero, whereas CH(3)OOI was formed efficiently at 70 Torr N(2). Similarly, no evidence was found for IO formation in the CF(3)O(2) + I reaction. An estimate of the rate coefficients k(CH(3)O(2) + I) = 2 x 10(-11) cm(3) molecule(-1) s(-1) and k(CH(3)OOI + I) = 1.5 x 10(-10) cm(3) molecule(-1) s(-1) was also obtained. The results on k(1)-k(3) are compared to the limited number of previous investigations and the implications for the chemistry of the marine boundary layer are briefly discussed.

  16. Water permeability of aquaporin-4 channel depends on bilayer composition, thickness, and elasticity.

    PubMed

    Tong, Jihong; Briggs, Margaret M; McIntosh, Thomas J

    2012-11-07

    Aquaporin-4 (AQP4) is the primary water channel in the mammalian brain, particularly abundant in astrocytes, whose plasma membranes normally contain high concentrations of cholesterol. Here we test the hypothesis that the water permeabilities of two naturally occurring isoforms (AQP4-M1 and AQP4-M23) depend on bilayer mechanical/structural properties modulated by cholesterol and phospholipid composition. Osmotic stress measurements were performed with proteoliposomes containing AQP4 and three different lipid mixtures: 1), phosphatidylcholine (PC) and phosphatidylglycerol (PG); 2), PC, PG, with 40 mol % cholesterol; and 3), sphingomyelin (SM), PG, with 40 mol % cholesterol. The unit permeabilities of AQP4-M1 were 3.3 ± 0.4 × 10(-13) cm(3)/s (mean ± SE), 1.2 ± 0.1 × 10(-13) cm(3)/s, and 0.4 ± 0.1 × 10(-13) cm(3)/s in PC:PG, PC:PG:cholesterol, and SM:PG:cholesterol, respectively. The unit permeabilities of AQP4-M23 were 2.1 ± 0.2 × 10(-13) cm(3)/s, 0.8 ± 0.1 × 10(-13) cm(3)/s, and 0.3 ± 0.1 × 10(-13) cm(3)/s in PC:PG, PC:PG:cholesterol, and SM:PG:cholesterol, respectively. Thus, for each isoform the unit permeabilities strongly depended on bilayer composition and systematically decreased with increasing bilayer compressibility modulus and bilayer thickness. These observations suggest that altering lipid environment provides a means of regulating water channel permeability. Such permeability changes could have physiological consequences, because AQP4 water permeability would be reduced by its sequestration into SM:cholesterol-enriched raft microdomains. Conversely, under ischemic conditions astrocyte membrane cholesterol content decreases, which could increase AQP4 permeability.

  17. Changes in thyroid parameters of hatchling American kestrels (Falco sparverius) following embryonic exposure to technical short chain chlorinated paraffins (SCCPs; C10-13, 55.5% CL)

    USGS Publications Warehouse

    Fernie, Kimberly J; Henry, Paula F.; Letcher, Robert J; Palace, Vince; Peters, Lisa; Rattner, Barnett A.; Sverko, Edward; Karouna, Natalie

    2015-01-01

    Chlorinated paraffins (CPs) are complex mixtures of polychlorinated n-alkanes categorized according to their carbon chain length: short chain (SCCPs, C10 – C13), medium (C14 - C17), and long chain (C>17), chlorinated paraffins. SCCPs are primarily used in metalworking applications, as flame retardants, and in paints, adhesives, sealants, textiles, plastics and rubber (UNEP 2012). In 2012, the United Nations Environment Program (UNEP 2012) reported in the Revised Draft Risk Profile for SCCPs, that CPs were produced in the United States, the European Union (EU), Slovakia, Brazil, India, Japan and China. While annual global consumption of SCCPs is large (>25 tonnes/year), it has sharply declined over the past 20 years. SCCPs are released through wastewater, landfills, and air emissions (UNEP 2012). Concentrations of SCCPs have been reported in fish and marine mammals in North and South America, Europe, Japan, Greenland and the Arctic (UNEP 2012 and references therein). Characterization of SCCP concentrations and exposure in terrestrial wildlife is limited. In 2010, SCCP concentrations were reported in the eggs of yellow-legged gulls (Larus michahellis) (4536 ± 40 pg/g wet weight (ww)) and Audouin’s gulls (Larus audouinii) (6364 ± 20 pg/g ww) in Spain (Morales et al. 2012), and little auks (Alle alle) (5 - 88 ng/g ww) and kittiwakes (Rissa tridactyla) (5 - 44 ng/g ww) in the European Arctic (Reth et al. 2006). In Sweden, muscle of ospreys contained CPs of unspecified chain length (Jansson et al. 1993). Although the toxicity of SCCPs has been demonstrated in aquatic invertebrates, fish, frogs, and laboratory rats, there are limited avian studies and these reported no effects of SCCPs on egg parameters of domestic hens (Gallus gallus domesticus) and ducks (Anas platyrhynchos) (UNEP 2012). Despite reported accumulation of SCCPs in wild birds, to our knowledge, exposure-related toxicities and effects with respect to avian wildlife remain unknown.

  18. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... integrated circuit. If the movement in question is subject to the specific rate of duty of 75 cents if the value of the assembled movement is $30, and if the value of the American-made integrated circuit is $10, then the value of the integrated circuit represents one third of the total value of the...

  19. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... integrated circuit. If the movement in question is subject to the specific rate of duty of 75 cents if the value of the assembled movement is $30, and if the value of the American-made integrated circuit is $10, then the value of the integrated circuit represents one third of the total value of the...

  20. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... integrated circuit. If the movement in question is subject to the specific rate of duty of 75 cents if the value of the assembled movement is $30, and if the value of the American-made integrated circuit is $10, then the value of the integrated circuit represents one third of the total value of the...

  1. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... integrated circuit. If the movement in question is subject to the specific rate of duty of 75 cents if the value of the assembled movement is $30, and if the value of the American-made integrated circuit is $10, then the value of the integrated circuit represents one third of the total value of the...

  2. 19 CFR 10.13 - Statutory provision: Subheading 9802.00.80, Harmonized Tariff Schedule of the United States (19 U...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... integrated circuit. If the movement in question is subject to the specific rate of duty of 75 cents if the value of the assembled movement is $30, and if the value of the American-made integrated circuit is $10, then the value of the integrated circuit represents one third of the total value of the...

  3. National Research Conference on Day Programs for Hearing Impaired Children (Lake Mohonk, New York, May 10-13, 1967). Final Report.

    ERIC Educational Resources Information Center

    Mulholland, Ann M.; Fellendorf, George W.

    State needs in public school education for the hearing impaired and steps in the development of comprehensive state planning are presented along with recommendations of conference participants, a summary report, and models for regional planning, day programs, and the team approach. The interest of the Alexander Graham Bell Association and the U.S.…

  4. Women and the American Economy: A Bicentennial Appraisal. Proceedings of the Air Force Academy Assembly (18th, Colorado Springs, Colorado, March 10-13, 1976).

    ERIC Educational Resources Information Center

    Haffa, Robert P., Jr., Ed.

    The proceedings delve into facets of the women's movement in America and, particularly the effect of women on the national economy. Highlighted are the speeches to the Assembly of Ms. Betty Friedan, Mrs. Catherine East, Dr. Peggy Kruger, Dr. Jean Lipman-Blumen, and Mrs. Phyllis Schlafly, as well as a final report adopted by the Assembly. The…

  5. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part I: Media History.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Media History section of this collection of conference presentations contains the following 21 papers: "Social Class Advocacy Journalism: Prelude to Party Politics, 1892" (David J. Vergobbi); "Pilfering the News: A Quality Comparison of the World and Journal's Spanish-American War Coverage" (Randall S. Sumpter); "The…

  6. The Value of the Studied Item in the Matching Criterion in Differential Item Functioning (DIF) Analysis. Research Report. ETS RR-10-13

    ERIC Educational Resources Information Center

    Tan, Xuan; Xiang, Bihua; Dorans, Neil J.; Qu, Yanxuan

    2010-01-01

    The nature of the matching criterion (usually the total score) in the study of differential item functioning (DIF) has been shown to impact the accuracy of different DIF detection procedures. One of the topics related to the nature of the matching criterion is whether the studied item should be included. Although many studies exist that suggest…

  7. Online Catalog Screen Displays. A Series of Discussions. Report of a Conference Sponsored by the Council on Library Resources (Austin, Texas, March 10-13, 1985).

    ERIC Educational Resources Information Center

    Williams, Joan Frye, Ed.

    Papers presented and summaries of discussions at a 3-day conference which focused on screen displays for online catalogs are included in this report. Papers presented were: (1) "Suggested Guidelines for Screen Layouts and Design of Online Catalogs" (Joseph R. Matthews); (2) "Displays in Database Search Systems" (Fran Spigai);…

  8. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part X: Miscellaneous Studies.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Miscellaneous Studies section of this collection of conference presentations contains the following 22 papers: "Men and Women Journalists in the Movies: Exploration of Some Sexism and Gender Issues in Their Portrayals in Eleven Films" (Albert D. Talbott); "Female Archetypes in Late '80s Films" (Fakhri Haghani); "Chain…

  9. μ-Hexa-thio-metadiphosphato-bis-[(1,4,7,10,13,16-hexa-oxa-cyclo-octa-decane-κ(6) O)rubidium] aceto-nitrile disolvate.

    PubMed

    Gjikaj, Mimoza; Pook, Niels-Patrick; Qarri, Flora

    2013-12-01

    The asymmetric unit of the title compound, [Rb2(P2S6)(C12H24O6)2]·2CH3CN, contains one half of an [Rb(18-crown-6)2]2[P2S6] unit and one aceto-nitrile solvent mol-ecule. The [Rb(18-crown-6)]2[P2S6] unit is completed by inversion symmetry. Its Rb(+) ion is situated near the centre of the macrocyclic cavity, but is displaced by 0.8972 (1) Å from the O atoms of the crown in the direction of the [P2S6](2-) moiety. The overall coordination number of the cation is eight, defined by the six crown ether O atoms and by two terminal S atoms of the [P2S6](2-) anion. The hexa-thio-metadiphosphate anion is built up from two tetra-hedral PS4 units joined together by a common edge. The crystal structure is characterized by alternating layers of [Rb(18-crown-6)]2[P2S6] and aceto-nitrile solvent mol-ecules stacked along [010].

  10. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Radio and Television Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Radio and Television section of the proceedings contains the following 13 papers: "Two Pacific Powers View the World: News on CBS and TBS Television" (Anne Cooper-Chen); "Nicholas Johnson: The Public's Defender on the Federal Communication Commission, 1966-1973" (Max V. Grubb); "News Tips, TV Viewers, and Computer…

  11. Immobilized alpha-melanocyte stimulating hormone 10-13 (GKPV) inhibits tumor necrosis factor-alpha stimulated NF-kappaB activity.

    PubMed

    Kelly, J M; Moir, A J G; Carlson, K; Yang, Y; MacNeil, S; Haycock, J W

    2006-02-01

    alpha-MSH is an anti-inflammatory peptide which signals by binding to the melanocortin-1 receptor (MC1R) and elevating cyclic AMP in several different cells and tissues. The carboxyl terminal peptides of alpha-MSH (KPV/GKPV) are the smallest minimal sequences that prevent inflammation, but it is not known if they operate via MC1R or cyclic AMP. The aim of this study was to examine the intracellular signaling potential of the GKPV peptide sequence when immobilized to polystyrene beads via a polyethylene glycol moiety. Beads containing an immobilized GKPV peptide were investigated for their ability to inhibit proinflammatory tumor necrosis factor-alpha (TNF-alpha) stimulated activation of NF-kappaB in HBL cells stably transfected with an NF-kappaB-luciferase reporter construct. Peptide functionalized beads were compared with the ability of soluble peptide alone (alpha-MSH or GKPV) or non-functionalized beads to inhibit TNF-alpha stimulated activation of NF-kappaB. GKPV peptide functionalized beads significantly inhibited NF-kappaB-luciferase activity in comparison to beads containing no peptide moiety in one of two growths conditions investigated. Soluble alpha-MSH and GKPV peptides were also confirmed to inhibit NF-kappaB-luciferase. The present study suggests that the carboxyl terminal MSH peptide acts via a cell receptor-based mechanism and furthermore may support the potential use of such immobilized ligands for anti-inflammatory therapeutic use.

  12. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 5 - Geothermal power/energy program

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    This volume examines the geothermal resource and geothermal energy utilization, and surveys regional energy programs worldwide. The particular papers presented on geothermal energy include those on the temperature indicators for geothermal use, geothermal drilling research in the United States, and geothermal energy and biofuel production in agriculture. Energy programs from India, Egypt, Turkey, Greece and Puerto Rico are reviewed.

  13. Alternative energy source II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 6 - Nuclear energy

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    This volume examines conventional nuclear energy, breeder reactors, and thermonuclear energy. The particular papers presented consider current developments in nuclear breeder technology, fusion-driven fissile fuel breeder systems, and the fusion fission hybrid reactor. The implications of nuclear energy utilization in the Phillipines and the internationally safeguarded atomic fuel exchanger center for the Asian-Pacific basin are also discussed.

  14. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 8 - Hydrogen energy

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    The book discusses the topics of electrolytic hydrogen production, thermochemical hydrogen production, solar hydrogen production, metal hydrides, and hydrogen utilization. Several papers are presented on the development status of the steam-iron process for hydrogen production, the production of hydrogen from carbonaceous materials, biophotolysis systems for hydrogen production, and heat transfer enhancement in metal hydride systems. Fixed site hydrogen storage is examined with a view to the applications impact, and a comparison of technologies and economics.

  15. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 4 - Indirect solar energy

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    This volume gives consideration to the topics of wood energy, wind turbines and siting, wind power generation, wave and current energy, tide energy and ocean thermal energy. Particular attention is given to the performance analysis of vertical axis wind turbines, estimating wind potential for small scale energy generation, and the effects of wind integration with conventional electrical generating systems. The development of tidal power in Korea, the design of the OTEC Seacoast Test Facility at Keahole Point, Hawaii, and wind energy utilization possibilities in Turkey are reviewed.

  16. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 7 - Hydrocarbon conversion

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    Consideration is given to such topics as coal gasification and liquefaction, the combustion of alcohol fuels, hydrocarbon upgrading and combustion technology, novel engines using hydrocarbon fuel, and hydrocarbons economics and planning. Particular papers are presented on the role of high-Btu coal gasification technology, ethanol from municipal cellulosic wastes, the fluidized bed combustion of coal, the behavior of gas distribution equipment in hydrogen service, and the economics of advanced technologies for electricity generation from coal.

  17. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 3 - Solar energy 3

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    The book examines the topics of distillation, thermal power, direct electrical conversion, and solar energy economics and planning. Several papers are presented on the subjects of thin film photovoltaic solar energy conversion, the solar thermionic power plant, the construction cost of thermal storage for solar systems, and the thermodynamic method for the quantitative treatment of conduction electrons.

  18. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part IX: Magazines.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Magazines section of this collection of conference presentations contains the following 15 papers: "'National Geographic Magazine' and the Vietnam War: Did We Just Get Pretty Pictures?" (John W. Williams); "Free Speech at All Costs: A Short History of 'The Masses'" (Chris Lamb); "Newspapers Locally Edited Magazines…

  19. Specific loss of chromosomes 1, 2, 6, 10, 13, 17, and 21 in chromophobe renal cell carcinomas revealed by comparative genomic hybridization.

    PubMed Central

    Speicher, M. R.; Schoell, B.; du Manoir, S.; Schröck, E.; Ried, T.; Cremer, T.; Störkel, S.; Kovacs, A.; Kovacs, G.

    1994-01-01

    We analyzed 19 chromophobe renal cell carcinomas by means of comparative genomic hybridization. Two tumors revealed no numerical abnormalities. In the remaining 17 cases we found loss of entire chromosomes with underrepresentation of chromosome 1 occurring in all 17 cases; loss of chromosomes 2, 10, and 13 in 16 cases; loss of chromosomes 6 and 21 in 15 tumors; and loss of chromosome 17 in 13 cases. The loss of the Y chromosome was observed in 6 of 13 tumors from male patients, whereas 1 X chromosome was lost in 3 of 4 tumors obtained from females. Comparative genomic hybridization results were verified by interphase cytogenetics. We conclude that a specific combination of multiple chromosomal losses characterizes chromophobe renal cell carcinomas and may help to differentiate them unequivocally from other types of kidney cancer. Images Figure 1 Figure 2 PMID:7519827

  20. The Cartographic Representation of Linguistic Data. Discussion Papers in Geolinguistics Nos. 19-21. Selected Papers from a Geolinguistic Seminar (Le Pailly, France, September 10-13, 1992).

    ERIC Educational Resources Information Center

    Peeters, Yvo J. D., Ed.; Williams, Colin H., Ed.

    Papers from a conference on cartography in geolinguistics include: "The Political Importance of Visualisation of Language Contact" (Yvo J. D. Peeters); "Some Considerations on People and Boundaries" (Guy Heraud); "Geolinguistic Developments and Cartographic Problems" (Colin H. Williams, John E. Ambrose); "A…

  1. The role of polymorphism of interleukin-2, -10, -13 and TNF-α genes in cutaneous T-cell lymphoma pathogenesis

    PubMed Central

    Olszewska, Berenika; Roszkiewicz, Jadwiga; Glen, Jolanta; Zabłotna, Monika; Ługowska-Umer, Hanna; Nowicki, Roman; Sokołowska-Wojdyło, Małgorzata

    2016-01-01

    Introduction As the pathogenesis of cutaneous T-cell lymphomas (CTCL) is not fully understood, inherited gene polymorphisms are considered to play a role in the development of lymphomas. Aim To investigate whether certain gene polymorphisms might be involved in the development of CTCL. Material and methods In the case-control study we compared the frequency of nine selected single nucleotide polymorphisms (SNP) of seven genes (rs1800587/–889 C/T of interleukin (IL)-1α, rs2069762/–330G/T) and rs2069763/+166G/T of IL-2, rs1800925/–1112 C/T of IL-13, rs1800896/–1082 A/G of IL-10, rs4073/–251 A/T of IL-8, rs5370/K198N, rs180054/–1370T/G of endothelin-1 and rs1800629/–308 G/A of TNF-α) in 43 CTCL and Polish cases using the amplification refractory mutation system polymerase chain reaction method. Results We have found that two genotypes, –330GG of IL-2 and –1112TT of IL-13 both promoter variants associated with “hypertranscription phenotype”, were over-represented in CTCL patients compared to healthy controls, and they increase the risk of malignancy development (OR = 5.82, p = 0.001 for IL-2 –330 GG, and OR = 5.67, p = 0.0024 for IL-13 –1112 TT). On the other hand, high transcription –308A allele of the TNF-α gene and –1082GG of IL-10 genotype is less frequent in lymphoma patients and has protective effects on the development of CTCL (OR = 0.45, p = 0.0466 for –308A of TNF-α, and OR = 0.35, p = 0.0329 for –1082GG of IL-10 genes). Conclusions Our results indicate that hypertranscription promoter variants of IL-2 and IL-13 genes could be estimated as the risk factor for development of CTCL, while TNF-α and IL-10 variants have a protective effect. PMID:28035219

  2. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Qualitative Studies Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Qualitative Studies section of the proceedings contains the following 13 papers: "Writing as Theater: The Marketing of the Digital Word" (Sally McMillan); "Rethinking Ideology: Polysemy, Pleasure and Hegemony in Television Culture" (Luis Rivera-Perez); "Low Power FM: A Small History" (Gregory J. Adamo); "The…

  3. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). History Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The history section of the Proceedings contains the following 17 papers: "A Bid for Legitimacy: The Women's Press Club Movement, 1881-1900" (Elizabeth V. Burt); "'Securing the Affections of Those People at This Critical Juncture': Newspaper Portrayal of Colonial-Native American Relations, 1754-1763" (David A. Copeland);…

  4. The Changing Face of Adult Learning. Adult Higher Education Alliance/ACE Conference Proceedings (Austin, TX, October 10-13, 2001).

    ERIC Educational Resources Information Center

    Adult Higher Education Alliance.

    These proceedings included the following papers: "The Language of Interdisciplinary Programs or 'What Do You Mean By That?'" (Ezzell, Turner); "When Mothers Become Students: Impact on Children and the Family System" (Burns, Gabrick); "Multi-Discipline Theorizing Meets the Blackboard: The Evolving Discourse Community"…

  5. Proceedings of Symposium on Analysis and Detection of Explosives (3rd) Held in Mannheim-Neuostheim (Germany, F.R.) on 10-13 July 1989

    DTIC Science & Technology

    1989-07-13

    do l 𔄀jection dui bourrago, l 𔄀quilibre chimique est. rompu A uno temptraturo plus 6lovoa quo lorsque los grains do nitrate d’ammonium sont petits...been tested. The results from these analyses axe di~crutsed and the advantages cf the different methods are descrlý-,d. 1. INTRODUCTION HM! (Octahydro- l ...R.O. Keto V 12 ANALYSIS OF REACTION PRODUCTS OF PROPELLANTS 12-1 AND HIGH EXPLOSIVES F. Yolk V 13 FUMiES DE TIRS L -EXPERIENCE DU CERCHAR 13-1 AVEC UNE

  6. Physiologic adaptation of man in space; Proceedings of the Seventh International Man in Space Symposium, Houston, TX, Feb. 10-13, 1986

    NASA Technical Reports Server (NTRS)

    Holland, Albert W. (Editor)

    1987-01-01

    Topics discussed in this volume include space motion sickness, cardiovascular adaptation, fluid shifts, extravehicular activity, general physiology, perception, vestibular response modifications, vestibular physiology, and pharmacology. Papers are presented on the clinical characterization and etiology of space motion sickness, ultrasound techniques in space medicine, fluid shifts in weightlessness, Space Shuttle inflight and postflight fluid shifts measured by leg volume changes, and the probability of oxygen toxicity in an 8-psi space suit. Consideration is also given to the metabolic and hormonal status of crewmembers in short-term space flights, adaptive changes in perception of body orientation and mental image rotation in microgravity, the effects of a visual-vestibular stimulus on the vestibulo-ocular reflex, rotation tests in the weightless phase of parabolic flight, and the mechanisms of antimotion sickness drugs.

  7. [Figures of first laureates of the Wiktor Dega medal (XXXVII Jubilee Congress of Polish Orthopaedic and Traumatologic Society, 10-13 September 2008)].

    PubMed

    Nowakowski, Andrzej; Rapała, Kazimierz

    2008-01-01

    Figures of two outstanding orthopaedists Professor Stefan Malawski and Professor Jerzy Król rewarded with the medal of the name of Wiktor Degi were described. The medal is being granted by the Chapter of the Medal as regarding for outstanding achievements for the Polish and world orthopaedics and rehabilitation. Profesor Stefan Kazimierz Malawski was born 26. 12. 1920 in the Vilnius area. In Vilnius he stated his medical studies, which he continued in Lwow and graduated in 1946 at the Marie Curie Skłodowska in Lublin. Professor Malawski's main field of interest were related to the problems related to tuberculosis of bones and joints and trauma of the lumbar and cervical spine. In the problems of bone tuberculosis he remains an unquestioned authority in Poland. His deep understanding of these clinical problems can be found in his text-book "Tuberculosis of bones and joints", which was printed in 1976. The information pertaining diagnosis and surgical treatment remain extremely valuable today. Another field of interest of Professor Malawski are pathologies of the spine. Disc disease, neoplasms of the spine, spinal stenosis and infections of the spine, spondylolisthesis are among many of his interests. This very wide field of interest can be dound in his 3 tome publication Spondyloorthopedics. His 166 papars printed in Poland and abroad bear proof of the Professors wide field of interest and deep knowledge. Professor Malawski was the first surgeon in Poland to perform surgery on the front elements of the spine in tuberculotic paraplegia. In 1958 he implemented surgical treatment of spine tumor--both primary and metastatic, by resecting them and stabilizing the spine with grafts. In the early 70's he focused on spinal stenosis. In the years 1982-1986 he was the Chairman of the Board of the Polish Orthopedic and Trauma Society. Professor Malawski introdued a modern set of Rules and Regulations, greatly simplifying the decision making process during General assemblies of the Society. Professor Malawski is undoubtedly a great successor to the active way of surgical thinking introduced by professor Adam Gruca. Professor Jerzy Król is among the greatest Polish orthopedic surgeons. He was born on 21st February 1926 in Baranowice (Nowogródek woiwodship). He graduated from high school in the underground schooling system during the Second World War, receiving his maturity exam in 1945 from the Konarski High Scool School of the Western Lands in Czestochowa. In 1945 the professor started his medical studies at Adam Mickiewicz University of Poznan, where he graduated in 1949. In 1950 he started his medical career in in Orthopedic Department of Poznan head by professor Wiktor Dega. Professor Król is the author of over 100 medical papers printed in national and international journals. His key fields of interest are congenital dislocation of the hip, hip arthroplasty, scoliosis and rehabilitaton and prosthesis problems. In 1968 he performed the first scoliosis correction with the Harrington rod in Poland as well as the implantation of the first McKee-Ferara hip prosthesis. He is the co-author of the text-book Orthopedics and Rehabilitation, Medical Rehabilitation and a number of WHO text books: Community Health Worker and Guide for prevention of Deformities in Poliomyelitis. He also took part in the publishing of the WHO text-book Rehabilitation Surgery, for which he received the Ministry of Health Award. He overlooked 7 Ph.D thesis and 4 papers qualifying for assistant professor. Between 1972 and 1995 professor Król worked as a WHO expert, as member of the Expert Committee for Rehabilitation. Between 1986-1987 head was the director of the Orthopedics and Rehabilitation Institute in Poznan. He resigned from this function due to his work with WHO in Madagaskar. After his return he was the head of the Orthopedic Department in Poznan University of Medical Sciennces until October 1996 when he retired.

  8. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). International Communications Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The international communications section of the Proceedings contains the following 14 papers: "Spinning Stories: Latin America and the World Wide Web" (Eliza Tanner); "Private-Enterprise Broadcasting and Accelerating Dependency: Case Studies from Nigeria and Uganda" (Folu Folarin Ogundimu); "The Transitional Media System…

  9. Abstracts of Papers Presented at the Annual Meeting of the Society of General Physiologists Held at Woods Hole, Massachusetts on 10-13 September 1992.

    DTIC Science & Technology

    1992-09-13

    cDNAs coding for membrane-bound receptors from eukaryotes and prokaryotes revealed the topographic feature of 7-transmembrane (7-TM) helices as a common...Departments of Medicine and Pharma- cology, Tufts University School of Veterinary Medicine, North Grafton, Massachusetts Cellular mechanisms by which...Department of Anatomy and Cell Biology, Emory University, Atlanta, Georgia (Sponsor: R. DeHaan) The rapid removal of extracellular neurotransmitter after

  10. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part IV: International Media.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The International Media section of this collection of conference presentations contains the following 15 papers: "Testing the Interaction of the Third-Person Effect and Spiral of Silence in a Political Pressure Cooker: The Case of Hong Kong" (Lars Willnat); "The Use of Small State Variables in Research on Coverage of Foreign Policy:…

  11. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Miscellaneous Studies Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Miscellaneous Studies Division of these Proceedings contains the following 13 papers: "A Trend, Imagined or Real? A Comparative Study of Development Journalism and Public Journalism" (Jiafei Yin); "Investigative Reporting about Minorities in America" (Tim Gallimore and Lillian Dunlap); "A Defining Moment: Who Says What…

  12. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 9 - Conservation, economics, and policy; Index

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    The book examines the topics of waste utilization, conservation, and energy economics and policy. Energy supply and demand, energy economics and planning, and energy strategies and policies are reviewed. Papers are presented on the contributions to the energy supply of the industrialized countries from nuclear energy and regenerative energy flows, a method for estimating escalation and interest during construction, and a comparison of the incentives used to stimulate energy production between the United States and Japan.

  13. Rate Processes in Dissipative Systems: 50 Years After Kramers, Discussion Meeting Held in Tutzing (Germany, F.R.) on 10-13 September 1990

    DTIC Science & Technology

    1990-09-13

    alkanes at ambient temperature. We model this increasing in conjunction with the high pressure fluorescence cell about 100 ps, solvation in solvent...method to take full advantage of the high repetition rate tion [M]: of the instrument. Fluorescence lifetimes measured at ambient pres- sure in a...complished by the analysis of measurements at ambient q. pressure alone. Additional studies of the temperature and pressure dependence appear obligatory

  14. Annals of the New York Academy of Sciences. Volume 423. Timing and Time Perception Held at New York on 10-13 May 1983,

    DTIC Science & Technology

    1984-05-13

    thait sensitivity to frequenc change exists in distinct "’frequency channels." ’ ’ 3SNidAJ IN3V1NLiAOU IV (1JJ1OOdi ," .. 𔃻.. 101) ANNAlS NEW VORK ACAI ...8217, 132 ANNALS NE"%N )RK ACAI )EIl OF S( tE( Is% question "Why does a response criterion have one value rather than another " lni J offers the answer that...34 , ,,.-.’. ...--.. ...... ,.•., .... •. . . . . . .. . . .... . . . . .- ,., 164 ANNAlS NEW ’ YORK ACAI )EMt OF S(IF(FS Procedure Subjects were instructed. via

  15. National Computer Security Conference Proceedings (12th): Information Systems Security: Solutions for Today - Concepts for Tomorrow Held in Baltimore, Maryland on 10-13 October 1989

    DTIC Science & Technology

    1989-10-13

    is not without some risk. The main risk seems to be the relh_,e being placed upon the FITLS. Any flaws in it will adversely affect the security...bulletin board ware needs. Your supplier is (public domain software, well-known, widely used, and even vaccines !). A new has a good track record of sup...353 Specialized Software Many commercial vendors now offer " vaccine " programs, software designed to limit your computer’s exposure to virus programs

  16. Abstracts. 1978 AFOSR Contractors Meeting on Air-Breathing Combustion Dynamics and Kinetics, Ramada Inn-Downtown Dayton, Ohio, 10 - 13 October 1978

    DTIC Science & Technology

    1978-10-13

    aircraft operations, jet fuels of the future are likely to be produced from a combination of basic synthetic crudes; ie, coal, oil, shale , tar sand, etc...a mechanical shaker . A pulse generator-function generator-power amplifier combination was used to generate a 2-cycle burst of a given frequency which...above 300 Hz). In the other configuration, the piston- shaker was used to establish first a standing wave in the reaction tube at one of its resonant

  17. Effect of flushing of blastocysts on days 10-13 on the life-span of the corpora lutea in the pig.

    PubMed

    van der Meulen, J; Helmond, F A; Oudenaarden, C P

    1988-09-01

    Blastocysts were flushed out of both uterine horns of gilts on Days 10, 11, 12 or 13. In mated non-pregnant gilts flushing had no effect on progesterone profile or cycle length (20.8 +/- 0.4 versus 20.6 +/- 0.6 days in the preflush cycle, N = 6, mean +/- s.e.m.). Flushing the blastocysts out of the uterine horns on Day 10 resulted in a cycle with a normal progesterone profile and a normal length (21.2 +/- 0.4 days, N = 5). Flushing on Days 11, 12 or 13 resulted in a normal cycle or in maintenance of the CL for 3-13 days as indicated by elevated progesterone concentrations and an increased interoestrous interval of, respectively, 22.0 +/- 1.2 versus 19.8 +/- 0.6 days (Day 11; N = 6), 24.8 +/- 1.4 versus 21.0 +/- 0.6 days (Day 12; N = 5; P less than 0.05) and 26.3 +/- 2.3 versus 20.5 +/- 0.4 days (Day 13; N = 6; P less than 0.05). There was a positive relationship between the change in interoestrous interval and the interval between the first observed standing oestrus and flushing of the blastocysts (rs = 0.350; n = 22; P less than 0.1). There was a large variation in the diameter of the blastocysts flushed on the same day. Only in those gilts in which the blastocysts were greater than or equal to 8 mm or filamentous were the CL maintained for 3 or more days. These results indicate that a first signal for maternal recognition of pregnancy is generated on Day 12 and that blastocysts greater than or equal to 8 mm are required for prolongation of CL function for 3 or more days. Since CL function is only extended for a maximum of 13 days (mean 7.4 +/- 1.0), a second signal seems necessary to maintain the CL for the whole period of pregnancy.

  18. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 2 - Solar Energy 2

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    The conference focused on heat transfer and energy transport, water heating, heat pumps, heating and cooling, and various applications of alternative energy sources. Papers are presented on the numerical resolution of the heat transfer equations in a latent heat solar energy storage system, the series solar heat pumps and energy conservation, solar air conditioning with solid absorbents and earth cooling, and the use of solar energy in multi-storied buildings.

  19. Communication, Community, Collaboration, Connection. Proceedings of the International Symposium on Telecommunications in Education (3rd, Albuquerque, New Mexico, November 10-13, 1994).

    ERIC Educational Resources Information Center

    Foster, David, Ed.; Jolly, Deborah V., Ed.

    New initiatives have provided educators with exciting resources to develop local, regional, and national infrastructures. Many new public and private sector collaborations have been the result, and this conference explores the implications of these changes for the education profession. The profession has focused on the various ethical issues…

  20. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Law Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The law section of the Proceedings contains the following 12 papers: "Middle Justice: Anthony Kennedy's Freedom of Expression Jurisprudence" (Evelyn C. Ellison); "Defending the News Media's Right of Access to the Battlefield" (Timothy H. Hoyle); "The Freedom of Information Act and Access to Computerized Government…

  1. Removing Barriers to the Adult Learner: Through Marketing, Management, and Programming. NUCEA Region VI Conference (Las Vegas, Nevada, October 10-13, 1982).

    ERIC Educational Resources Information Center

    Conter, Robert V., Ed.; Porcelli, Winifred A., Ed.

    These proceedings contain the texts of nine presentations delivered at a conference on removing barriers to the adult learner through marketing, management, and programing. Included in the volume are the following papers: "Faculty Perceptions of Adult Learners, Off-Campus Credit Programs, and Teaching Strategies," by Diane…

  2. Proceedings of the Conference on Flight Mechanics and System Design Lessons from Operational Experience Held at Athens, Greece on 10-13 May 1983.

    DTIC Science & Technology

    1983-10-01

    Les sujets suivants furent traites: - utilisation des enregistremients pour les operations afriennes quotidiennes -ernploi des terrains irr~guliers...to retain the last 30 minutes of information and the data recorders the last 15 to 25 hours. The majority of the military systems utilise a light...Unfortunately, more recent designs utilise packing densities as high as 817 bits/cm (2076 bits/in). For these tapes, we decided to investigate the use of

  3. The Effect of Vitamin D Administration on Intracellular Adhesion Molecule-1 and Vascular Cell Adhesion Molecule-1 Levels in Hemodialysis Patients: A Placebo-controlled, Double-blinded Clinical Trial

    PubMed Central

    Naeini, Afsoon Emami; Moeinzadeh, Firouzeh; Vahdat, Sahar; Ahmadi, Akbar; Hedayati, Zahra Parin; Shahzeidi, Safoora

    2017-01-01

    Objective: Vitamin D deficiency is quite common among end-stage renal disease (ESRD) patients, and Vitamin D administration could reduce morbidity and mortality in these patients through different mechanisms. Cardiovascular diseases are the most common cause of mortality in these patients that are caused by vascular injuries. Intracellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM) are vascular inflammation indicators. The goal of this study is to find the effect of Vitamin D administration on ICAM-1 and VCAM-1 serum levels in ESRD patients on hemodialysis. Methods: The current study is a double-blind, randomized, placebo-controlled clinical trial on 64 patients in two groups of control and treatment. Serum levels of Vitamin D, ICAM-1, and VCAM-1 were measured before and after the study. Treatment group was treated with Vitamin D pearls while control group underwent treatment with placebo pearls. Average serum levels of Vitamin D, ICAM, and VCAM were measured in both groups before and after the study and were analyzed by ANOVA, paired t-test, and Chi-square test using SPSS software. Findings: Sixty-four ESRD patients were recruited for this study consisting of 32 male and 32 female subjects within the ages of 18 and 76 years. The change in serum level of Vitamin D was significant in treatment group (P = 0.001) but not in control group (P > 0.05). Serum levels of ICAM and VCAM also changed significantly in treatment group (P = 0.001) but not in control group (P > 0.05) Conclusion: Based on the findings of this study, it could be said that Vitamin D administration in ESRD patients may increase serum level of Vitamin D up to four times. It also reduces serum levels of ICAM and VCAM which might improve the vascular condition of these patients.

  4. OH Radical Reaction Rate Coefficients, Infrared Spectrum, and Global Warming Potential of (CF3)2CFCH═CHF (HFO-1438ezy(E)).

    PubMed

    Papadimitriou, Vassileios C; Burkholder, James B

    2016-08-25

    Rate coefficients, k(T), for the OH radical + (E)-(CF3)2CFCH═CHF ((E)-1,3,4,4,4-pentafluoro-3-(trifluoromethyl)-1-butene, HFO-1438ezy(E)) gas-phase reaction were measured using pulsed laser photolysis-laser-induced fluorescence (PLP-LIF) between 214 and 380 K and 50 and 450 Torr (He or N2 bath gas) and with a relative rate method at 296 K between 100 and 400 Torr (synthetic air). Over the range of pressures included in this study, no pressure dependence in k(T) was observed. k(296 K) obtained using the two techniques agreed to within ∼3% with (3.26 ± 0.26) × 10(-13) cm(3) molecule(-1) s(-1) (2σ absolute uncertainty) obtained using the PLP-LIF technique. k(T) displayed non-Arrhenius behavior that is reproduced by (7.34 ± 0.30) × 10(-19)T(2) exp[(481 ± 10)/T) cm(3) molecule(-1) s(-1). With respect to OH reactive loss, the atmospheric lifetime of HFO-1438ezy(E) is estimated to be ∼36 days and HFO-1438ezy(E) is considered a very short-lived substance (VSLS) (the actual lifetime will depend on the time and location of the HFO-1438ezy(E) emission). On the basis of the HFO-1438ezy(E) infrared absorption spectrum measured in this work and its estimated lifetime, a radiative efficiency of 0.306 W m(-2) ppb(-1) (well-mixed gas) was calculated and its 100-year time-horizon global warming potential, GWP100, was estimated to be 8.6. CF3CFO, HC(O)F, and CF2O were identified using infrared spectroscopy as stable end products in the oxidation of HFO-1438ezy(E) in the presence of O2. Two additional fluorinated products were observed and theoretical calculations of the infrared spectra of likely degradation products are presented. The photochemical ozone creation potential of HFO-1438ezy(E) was estimated to be ∼2.15.

  5. Interleukin-6 and intercellular cell adhesion molecule-1 expression remains elevated in revived live endothelial cells following spaceflight.

    PubMed

    Muid, S; Froemming, G R A; Ali, A M; Nawawi, H

    2013-12-01

    The effects of spaceflight on cardiovascular health are not necessarily seen immediately after astronauts have returned but can be delayed. It is important to investigate the long term effects of spaceflight on protein and gene expression of inflammation and endothelial activation as a predictor for the development of atherosclerosis and potential cardiovascular problems. The objectives of this study were to investigate the (a) protein and gene expression of inflammation and endothelial activation, (b) expression of nuclear factor kappa B (NFκB), signal transducer and activator of transcription-3 (STAT-3) and endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC) 3 months post-space flight travel compared to ground controls. HUVEC cultured on microcarriers in fluid processing apparatus were flown to the International Space Station (ISS) by the Soyuz TMA-11 rocket. After landing, the cells were detached from microcarriers and recultured in T-25 cm(2) culture flasks (Revived HUVEC). Soluble protein expression of IL-6, TNF-α, ICAM-1, VCAM-1 and e-selectin were measured by ELISA. Gene expression of these markers and in addition NFκB, STAT-3 and eNOS were measured. Spaceflight induced IL-6 and ICAM-1 remain elevated even after 3 months post spaceflight travel and this is mediated via STAT-3 pathway. The downregulation of eNOS expression in revived HUVEC cells suggests a reduced protection of the cells and the surrounding vessels against future insults that may lead to atherosclerosis. It would be crucial to explore preventive measures, in relation to atherosclerosis and its related complications.

  6. Vibration-translation energy transfer in anharmonic diatomic molecules. 1: A critical evaluation of the semiclassical approximation

    NASA Technical Reports Server (NTRS)

    Mckenzie, R. L.

    1974-01-01

    The semiclassical approximation is applied to anharmonic diatomic oscillators in excited initial states. Multistate numerical solutions giving the vibrational transition probabilities for collinear collisions with an inert atom are compared with equivalent, exact quantum-mechanical calculations. Several symmetrization methods are shown to correlate accurately the predictions of both theories for all initial states, transitions, and molecular types tested, but only if coupling of the oscillator motion and the classical trajectory of the incident particle is considered. In anharmonic heteronuclear molecules, the customary semiclassical method of computing the classical trajectory independently leads to transition probabilities with anomalous low-energy resonances. Proper accounting of the effects of oscillator compression and recoil on the incident particle trajectory removes the anomalies and restores the applicability of the semiclassical approximation.

  7. Endothelial cells proactively form microvilli-like membrane projections upon intercellular adhesion molecule 1 engagement of leukocyte LFA-1.

    PubMed

    Carman, Christopher V; Jun, Chang-Duk; Salas, Azucena; Springer, Timothy A

    2003-12-01

    Specific leukocyte/endothelial interactions are critical for immunity and inflammation, yet the molecular details of this interaction interface remain poorly understood. Thus, we investigated, with confocal microscopy, the distribution dynamics of the central adhesion molecules ICAM-1 and LFA-1 in this context. Monolayers of activated HUVECs stained with fluorescent anti-ICAM-1 Fabs or Chinese hamster ovary-K1 cells expressing ICAM-1-green fluorescent protein were allowed to bind LFA-1-bearing monocytes, neutrophils, or K562 LFA-1 transfectants. ICAM-1 was rapidly relocalized to newly formed microvilli-like membrane projections in response to binding LFA-1 on leukocytes. These ICAM-1-enriched projections encircled the leukocytes extending up their sides and clustered LFA-1 underneath into linear tracks. Projections formed independently of VCAM-1/very late Ag 4 interactions, shear, and proactive contributions from the LFA-1-bearing cells. In the ICAM-1-bearing endothelial cells, projections were enriched in actin but not microtubules, required intracellular calcium, and intact microfilament and microtubule cytoskeletons and were independent of Rho/Rho kinase signaling. Disruption of these projections with cytochalasin D, colchicine, or BAPTA-AM had no affect on firm adhesion. These data show that in response to LFA-1 engagement the endothelium proactively forms an ICAM-1-enriched cup-like structure that surrounds adherent leukocytes but is not important for firm adhesion. This finding leaves open a possible role in leukocyte transendothelial migration, which would be consistent with the geometry and kinetics of formation of the cup-like structure.

  8. Soluble intercellular adhesion molecule-1 (sICAM-1) as a marker of disease relapse in idiopathic uveoretinitis.

    PubMed Central

    Zaman, A G; Edelsten, C; Stanford, M R; Graham, E M; Ellis, B A; Direskeneli, H; D'Cruz, D P; Hughes, G R; Dumonde, D C; Wallace, G R

    1994-01-01

    This study reports the results of a point prevalence study of markers of endothelial dysfunction in the serum of patients with idiopathic uveoretinitis. sICAM-1, soluble endothelial leucocyte adhesion molecule (sELAM), anti-endothelial cell antibodies (AECA) and von Willebrand factor (vWF) levels were measured in 32 patients with isolated idiopathic uveoretinitis and seven with uveitis in association with systemic disease, using commercial and in-house ELISAs. Raised levels of AECA were found in 31% of patients with isolated uveitis, vWF in 28%, sELAM in 15.6% and sICAM-1 in 31%. Further analysis revealed that raised sICAM-1 levels were closely associated with recent relapse of disease (P = 0.00003). Patients with accompanying systemic disease were found to have a similar prevalence of these serum abnormalities to those with isolated ocular disease. In conclusion, vascular endothelial dysfunction may contribute to pathogenesis in uveoretinitis, and in particular sICAM-1 may prove a marker of disease relapse in this condition. PMID:7507016

  9. Interferon gamma regulates platelet endothelial cell adhesion molecule 1 expression and neutrophil infiltration into herpes simplex virus- infected mouse corneas

    PubMed Central

    1996-01-01

    In a mouse model of herpes simplex virus (HSV) 1 corneal infection, tissue destruction results from a CD4+ T cell-mediated chronic inflammation, in which interleukin 2 and interferon (IFN) gamma are requisite inflammatory mediators and polymorphonuclear leukocytes (PMN) are the predominant infiltrating cells. In vivo neutralization of IFN- gamma relieved inflammation at least in part through a specific block of PMN extravasation into HSV-1-infected corneas. Intercellular adhesion molecule (ICAM) 1 and platelet endothelial cell adhesion molecule (PECAM) 1 were upregulated on the vascular endothelium of inflamed corneas. Reduced PMN extravasation in anti-IFN-gamma-treated mice was associated with a dramatic reduction of PECAM-1 but not ICAM-1 expression on vascular endothelium. PMN accumulated in the lumen of corneal vessels after in vivo IFN-gamma neutralization. PECAM-1 was readily detectable on PMN inside the vessels but was not detectable on PMN that extravasated into the infected cornea. Moreover, flow cytometric analysis revealed reduced PECAM-1 expression but elevated major histocompatibility complex class I expression on PMN that recently extravasated into the peritoneal cavity when compared with PMN in the peripheral blood. We conclude that IFN-gamma contributes to HSV- 1-induced corneal inflammation by facilitating PMN infiltration; this appears to be accomplished through upregulation of PECAM-1 expression on the vascular endothelium; and PMN downregulate PECAM-1 expression during the process of extravasation. PMID:8879215

  10. Suppression of complement regulatory protein C1 inhibitor in vascular endothelial activation by inhibiting vascular cell adhesion molecule-1 action

    SciTech Connect

    Zhang, Haimou; Qin, Gangjian; Liang, Gang; Li, Jinan; Chiu, Isaac; Barrington, Robert A.; Liu, Dongxu . E-mail: dxliu001@yahoo.com

    2007-07-13

    Increased expression of adhesion molecules by activated endothelium is a critical feature of vascular inflammation associated with the several diseases such as endotoxin shock and sepsis/septic shock. Our data demonstrated complement regulatory protein C1 inhibitor (C1INH) prevents endothelial cell injury. We hypothesized that C1INH has the ability of an anti-endothelial activation associated with suppression of expression of adhesion molecule(s). C1INH blocked leukocyte adhesion to endothelial cell monolayer in both static assay and flow conditions. In inflammatory condition, C1INH reduced vascular cell adhesion molecule (VCAM-1) expression associated with its cytoplasmic mRNA destabilization and nuclear transcription level. Studies exploring the underlying mechanism of C1INH-mediated suppression in VCAM-1 expression were related to reduction of NF-{kappa}B activation and nuclear translocation in an I{kappa}B{alpha}-dependent manner. The inhibitory effects were associated with reduction of inhibitor I{kappa}B kinase activity and stabilization of the NF-{kappa}B inhibitor I{kappa}B. These findings indicate a novel role for C1INH in inhibition of vascular endothelial activation. These observations could provide the basis for new therapeutic application of C1INH to target inflammatory processes in different pathologic situations.

  11. Intercellular adhesion molecule-1 (ICAM-1) in Graves' disease: contrast between in vivo and in vitro results.

    PubMed Central

    Ciampolillo, A; Napolitano, G; Mirakian, R; Miyasaki, A; Giorgino, R; Bottazzo, G F

    1993-01-01

    We have reassessed the possible role of the adhesion molecule ICAM-1 in the pathogenesis of thyroid autoimmunity. In order to do that, we have investigated its expression in eight Graves' thyroids both in vivo (i.e. on cryostat sections and on cell suspensions), and in vitro (i.e. on cells cultured in monolayers for 3 days), and the results were compared with those obtained with similar preparations from four normal glands. On cryostat sections, the expression of ICAM-1, and for comparison that of HLA Class I and Class II molecules, was studied by immunofluorescence (IFL), but the former were also assessed by a distinct immunohistochemical technique. ICAM-1 was not detected in thyrocytes in vivo of both normal and Graves' glands, but solely in endothelial cells and antigen-presenting cells (APC). This selective reaction was confirmed by a four-layer technique using specific markers which identify endothelial cells and thyrocytes. HLA Class II molecules were confirmed to be inappropriately expressed in thyrocytes of Graves' glands, but there was no co-expression of these products and ICAM-1 in the same cells. In contrast, ICAM-1 appeared de novo in a proportion of Graves' and normal thyrocytes soon after the attachment and spreading of these cells in monolayer cultures (36-48 h). Graves' thyrocytes showed a quantitatively higher degree of expression compared with that detected on normal thyroid cells (40-70% versus 12-20%). Under these experimental conditions, the four-layer staining with thyroid microsomal antibodies confirmed that thyrocytes were indeed the positive cells which expressed ICAM-1. Blocking experiments with cultured thyrocytes from two Graves' glands and MoAbs to tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) did not prevent the occurrence of ICAM-1 expression. As a result of our study, we failed to demonstrate that Graves' thyrocytes express ICAM-1 in vivo. The unexpected case of inducing ICAM-1 on thyroid cells under certain in vitro conditions remains intriguing. The phenomenon could be the simple consequence of a mechanical effect rather than exerted by specific biological processes. Further investigations are, therefore, needed to establish whether ICAM-1 is really involved in the pathogenesis of Graves' disease. Images Fig. 1 Fig. 2 Fig. 3 PMID:7902787

  12. Hematopoietic Progenitor Cell Rolling in Bone Marrow Microvessels: Parallel Contributions by Endothelial Selectins and Vascular Cell Adhesion Molecule 1

    PubMed Central

    Mazo, Irina B.; Gutierrez-Ramos, Jose-Carlos; Frenette, Paul S.; Hynes, Richard O.; Wagner, Denisa D.; von Andrian, Ulrich H.

    1998-01-01

    We have used intravital microscopy to study physiologically perfused microvessels in murine bone marrow (BM). BM sinusoids and venules, but not adjacent bone vessels, supported rolling interactions of hematopoietic progenitor cells. Rolling did not involve L-selectin, but was partially reduced in wild-type mice treated with antibodies to P- or E-selectin and in mice that were deficient in these two selectins. Selectin-independent rolling was mediated by α4 integrins, which interacted with endothelial vascular cell adhesion molecule (VCAM)-1. Parallel contribution of the endothelial selectins and VCAM-1 is not known to direct blood cell trafficking to other noninflamed tissues. This combination of constitutively expressed adhesion molecules may thus constitute a BM-specific recruitment pathway for progenitor cells analogous to the vascular addressins that direct selective lymphocyte homing to lymphoid organs. PMID:9687524

  13. Kinetics of the R + HBr ⇄ RH + Br (CH 3CHBr, CHBr 2 or CDBr 2) equilibrium. Thermochemistry of the CH 3CHBr and CHBr 2 radicals

    NASA Astrophysics Data System (ADS)

    Seetula, Jorma A.; Eskola, Arkke J.

    2008-07-01

    The kinetics of the reaction of the CH 3CHBr, CHBr 2 or CDBr 2 radicals, R, with HBr have been investigated in a temperature-controlled tubular reactor coupled to a photoionization mass spectrometer. The CH 3CHBr (or CHBr 2 or CDBr 2) radical was produced homogeneously in the reactor by a pulsed 248 nm exciplex laser photolysis of CH 3CHBr 2 (or CHBr 3 or CDBr 3). The decay of R was monitored as a function of HBr concentration under pseudo-first-order conditions to determine the rate constants as a function of temperature. The reactions were studied separately from 253 to 344 K (CH 3CHBr + HBr) and from 288 to 477 K (CHBr 2 + HBr) and in these temperature ranges the rate constants determined were fitted to an Arrhenius expression (error limits stated are 1σ + Student's t values, units in cm 3 molecule -1 s -1, no error limits for the third reaction): k(CH 3CHBr + HBr) = (1.7 ± 1.2) × 10 -13 exp[+ (5.1 ± 1.9) kJ mol -1/ RT], k(CHBr 2 + HBr) = (2.5 ± 1.2) × 10 -13 exp[-(4.04 ± 1.14) kJ mol -1/ RT] and k(CDBr 2 + HBr) = 1.6 × 10 -13 exp(-2.1 kJ mol -1/ RT). The energy barriers of the reverse reactions were taken from the literature. The enthalpy of formation values of the CH 3CHBr and CHBr 2 radicals and an experimental entropy value at 298 K for the CH 3CHBr radical were obtained using a second-law method. The result for the entropy value for the CH 3CHBr radical is 305 ± 9 J K -1 mol -1. The results for the enthalpy of formation values at 298 K are (in kJ mol -1): 133.4 ± 3.4 (CH 3CHBr) and 199.1 ± 2.7 (CHBr 2), and for α-C-H bond dissociation energies of analogous compounds are (in kJ mol -1): 415.0 ± 2.7 (CH 3CH 2Br) and 412.6 ± 2.7 (CH 2Br 2), respectively.

  14. A theoretical investigation on kinetics, mechanism, and thermochemistry of the gas-phase reactions of methyl fluoroacetate with OH radicals and fate of alkoxy radical.

    PubMed

    Mishra, Bhupesh Kumar; Deka, Ramesh Chandra

    2014-09-25

    We theoretically investigated OH-initiated hydrogen abstraction reactions of methyl fluoroacetate (MFA) CH2FC(O)OCH3 at the MPWB1K level of theory in conjunction with the 6-31+G(d,p) basis set. Thermodynamic and kinetic data are computed using the comparatively accurate G2(MP2) method. Two most stable conformers of MFA are identified, and the energy difference between them is found to be only 0.32 kcal mol(-1). Both of them are considered for rate coefficient calculations, and the contribution from each of the conformers is found to be quite significant. We propose an indirect mechanism due to validation of pre- and post-reactive complexes. The rate parameters are determined using canonical transition state theory and energetics at the G2(MP2) level. The temperature dependence of the rate constant can be described by the Arrhenius expressions: k = 8.79 × 10(-13) exp[(-377.27 ± 64)/T] cm(3) molecule(-1) s(-1) over a temperature range of 250-450 K. The ΔfH°298 for CH2FC(O)OCH3, CH2FC(O)OC(•)H2, and C(•)HFC(O)OCH3 are also computed using an isodesmic procedure. The OH-driven atmospheric lifetime of MFA was estimated to be 24 days. A mechanistic study to shed light on the atmospheric degradation and the sole fate for the consumption of CH2FC(O)OCH2O(•) radical has also been reported.

  15. Atmospheric chemistry of HFE-7300 and HFE-7500: Temperature dependent kinetics, atmospheric lifetimes, infrared spectra and global warming potentials

    NASA Astrophysics Data System (ADS)

    Rodríguez, Ana; Rodríguez, Diana; Moraleda, Araceli; Bravo, Iván; Moreno, Elena; Notario, Alberto

    2014-10-01

    The atmospheric degradation of two hydrofluoroethers, HFE-7300 [n-C2F5CF(OCH3)CF(CF3)2] and HFE-7500 [n-C3F7CF(OC2H5)CF(CF3)2] used in industrial applications has been studied. The kinetics and reaction products were determined at atmospheric pressure as a function of temperature in a reaction chamber using GC/FID and GC/MS techniques for the analysis. The following Arrhenius expressions were obtained (in units of cm3 molecule-1 s-1): kHFE-7300 + OH = (5.6 ± 2.0) × 10-13 exp(-(1186 ± 111)/T); kHFE-7300 + Cl = (3.8 ± 1.3) × 10-12 exp(-(968 ± 101)/T); and kHFE-7500 + OH = (7.6 ± 6.0) × 10-12 exp(-(1163 ± 385)/T) (temperature range 271-333 K). The atmospheric lifetimes calculated from kinetic data for HFE-7300 and HFE-7500 were 5.24 and 0.30 years, respectively. In the oxidation of HFE-7300 with OH and Cl radicals, the only detected product was CF3CF2CF(OCHO)CF(CF3)2, whereas in the oxidation of HFE-7500 by OH radicals the detected products were: C3F7CF(OC(O)CH3)CF(CF3)2 and C3F7CF(OC(O)H)CF(CF3)2. Infrared spectra of the studied HFEs have also been measured and radiative forcing efficiencies were determined. Combining these results with the kinetic data, we estimated 100-year time horizon global warming potentials of 440 and 12 for HFE-7300 and HFE-7500, respectively.

  16. Kinetics of the reactions of OH radicals with n-butyl, isobutyl, n-pentyl and 3-methyl-1-butyl nitrates

    NASA Astrophysics Data System (ADS)

    Bedjanian, Yuri; Morin, Julien; Romanias, Manolis N.

    2017-04-01

    The kinetics of the reactions of n-butyl (BTN), isobutyl (IBN), n-pentyl (PTN) and 3-methyl-1-butyl (3M1BN) nitrates with OH radicals has been studied using a low pressure flow tube reactor combined with a quadrupole mass spectrometer. The rate constants of the title reactions were determined under pseudo-first order conditions from kinetics of OH consumption in high excess of the nitrates. The overall rate coefficients, kBTN = 1.0 × 10-13 (T/298)3.36 exp(838/T) (T = 288-500 K), kIBN = 2.8 × 10-14 (T/298)4.09 exp(1127/T) (T = 283-500 K), kPTN = 1.26 × 10-12 (T/298)4.56 exp(45/T) (T = 298-496 K) and k3M1BN = 8.47×10-14 (T/298)3.52 exp(1069/T) cm3molecule-1s-1 (T = 288-538 K) (with conservative 15% uncertainty), were determined at a total pressure of 1 Torr of helium. The yields of the carbonyl compounds, n-butanal (n-C3H7CHO) and isobutanal ((CH3)2CHCHO), resulting from the abstraction by OH of an α-hydrogen atom in n-butyl and isobutyl nitrates, followed by α-substituted alkyl radical decomposition, were determined at T = 300 K to be 0.10 ± 0.02 and 0.15 ± 0.03, respectively. The calculated tropospheric lifetimes of BTN, IBN, PTN and 3M1BN indicate that reaction of these nitrates with OH represents an important sink of these compounds in the atmosphere.

  17. Atmospheric chemistry of Z- and E-CF3CH[double bond, length as m-dash]CHCF3.

    PubMed

    Østerstrøm, Freja F; Andersen, Simone Thirstrup; Sølling, Theis I; Nielsen, Ole John; Sulbaek Andersen, Mads P

    2016-12-21

    The atmospheric fates of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 have been studied, investigating the kinetics and the products of the reactions of the two compounds with Cl atoms, OH radicals, OD radicals, and O3. FTIR smog chamber experiments measured: k(Cl + Z-CF3CH[double bond, length as m-dash]CHCF3) = (2.59 ± 0.47) × 10(-11), k(Cl + E-CF3CH[double bond, length as m-dash]CHCF3) = (1.36 ± 0.27) × 10(-11), k(OH + Z-CF3CH[double bond, length as m-dash]CHCF3) = (4.21 ± 0.62) × 10(-13), k(OH + E-CF3CH[double bond, length as m-dash]CHCF3) = (1.72 ± 0.42) × 10(-13), k(OD + Z-CF3CH[double bond, length as m-dash]CHCF3) = (6.94 ± 1.25) × 10(-13), k(OD + E-CF3CH[double bond, length as m-dash]CHCF3) = (5.61 ± 0.98) × 10(-13), k(O3 + Z-CF3CH[double bond, length as m-dash]CHCF3) = (6.25 ± 0.70) × 10(-22), and k(O3 + E-CF3CH[double bond, length as m-dash]CHCF3) = (4.14 ± 0.42) × 10(-22) cm(3) molecule(-1) s(-1) in 700 Torr of air/N2/O2 diluents at 296 ± 2 K. E-CF3CH[double bond, length as m-dash]CHCF3 reacts with Cl atoms to give CF3CHClC(O)CF3 in a yield indistinguishable from 100%. Z-CF3CH[double bond, length as m-dash]CHCF3 reacts with Cl atoms to give (95 ± 10)% CF3CHClC(O)CF3 and (7 ± 1)% E-CF3CH[double bond, length as m-dash]CHCF3. CF3CHClC(O)CF3 reacts with Cl atoms to give the secondary product CF3C(O)Cl in a yield indistinguishable from 100%, with the observed co-products C(O)F2 and CF3O3CF3. The main atmospheric fate for Z- and E-CF3CH[double bond, length as m-dash]CHCF3 is reaction with OH radicals. The atmospheric lifetimes of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 are estimated as 27 and 67 days, respectively. IR absorption cross sections are reported and the global warming potentials (GWPs) of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 for the 100 year time horizon are calculated to be GWP100 = 2 and 7, respectively. This study provides a comprehensive description of the atmospheric fate and impact of Z- and E

  18. Hydrostatic pressure induced localization effects in InSb

    NASA Astrophysics Data System (ADS)

    Kadri, A.; Zitouni, K.; Aulombard, R. L.

    1986-05-01

    Magnetoresistance and Hall coefficient measurements were made as a function of free carrier concentration, pressure, temperature and magnetic field in samples of n-InSb with initial n in the range 2.1 × 10 13-1.4 × 10 14 cm -3. The free carrier concentrations could be controlled down to n « 10 11cm-3 both by using the metastable properties of the lattice coupled defects and by keeping the pressure at low temperatures. The results show clear evidence for the interplay between the correlation and the localization effects at the metal-insulator transition.

  19. Expression and polarization of intercellular adhesion molecule-1 on human intestinal epithelia: consequences for CD11b/CD18-mediated interactions with neutrophils.

    PubMed Central

    Parkos, C. A.; Colgan, S. P.; Diamond, M. S.; Nusrat, A.; Liang, T. W.; Springer, T. A.; Madara, J. L.

    1996-01-01

    BACKGROUND: Epithelial dysfunction and patient symptoms in inflammatory intestinal diseases such as ulcerative colitis and Crohn's disease correlate with migration of neutrophils (PMN) across the intestinal epithelium. In vitro modeling of PMN transepithelial migration has revealed distinct differences from transendothelial migration. By using polarized monolayers of human intestinal epithelia (T84), PMN transepithelial migration has been shown to be dependent on the leukocyte integrin CD11b/CD18 (Mac-1), but not on CD11a/CD18 (LFA-1). Since intercellular adhesion molecule-I (ICAM-1) is an important endothelial counterreceptor for these integrins, its expression in intestinal epithelia and role in PMN-intestinal epithelial interactions was investigated. MATERIALS AND METHODS: A panel of antibodies against different domains of ICAM-1, polarized monolayers of human intestinal epithelia (T84), and natural human colonic epithelia were used to examine the polarity of epithelial ICAM-1 surface expression and the functional role of ICAM-1 in neutrophil-intestinal epithelial adhesive interactions. RESULTS: While no surface expression of ICAM-1 was detected on unstimulated T84 cells, interferon-gamma (IFN gamma) elicited a marked expression of ICAM-1 that selectively polarized to the apical epithelial membrane. Similarly, apically restricted surface expression of ICAM-1 was detected in natural human colonic epithelium only in association with active inflammation. With or without IFN gamma pre-exposure, physiologically directed (basolateral-to-apical) transepithelial migration of PMN was unaffected by blocking monoclonal antibodies (mAbs) to ICAM-1. In contrast, PMN migration across IFN gamma-stimulated monolayers in the reverse (apical-to-basolateral) direction was inhibited by anti-ICAM-1 antibodies. Adhesion studies revealed that T84 cells adhered selectively to purified CD11b/CD18 and such adherence, with or without IFN gamma pre-exposure, was unaffected by ICAM-1 mAb. Similarly, freshly isolated epithelial cells from inflamed human intestine bound to CD11b/CD18 in an ICAM-1-independent fashion. CONCLUSIONS: These data indicate that ICAM-1 is strictly polarized in intestinal epithelia and does not represent a counterreceptor for neutrophil CD11b/CD18 during physiologically directed transmigration, but may facilitate apical membrane-PMN interactions after the arrival of PMN in the intestinal lumen. Images FIG. 3 FIG. 4 PMID:8827719

  20. Absence of Platelet Endothelial Cell Adhesion Molecule 1, PECAM-1/CD31, In Vivo Increases Resistance to Salmonella enterica Serovar Typhimurium in Mice

    PubMed Central

    Lovelace, Michael D.; Yap, May Lin; Yip, Jana; Muller, William; Wijburg, Odilia

    2013-01-01

    PECAM-1/CD31 is known to regulate inflammatory responses and exhibit pro- and anti-inflammatory functions. This study was designed to determine the functional role of PECAM-1 in susceptibility to murine primary in vivo infection with Salmonella enterica serovar Typhimurium and in in vitro inflammatory responses of peritoneal macrophages. Lectin profiling showed that cellular PECAM-1 and recombinant human PECAM-1-Ig chimera contain high levels of mannose sugars and N-acetylglucosamine. Consistent with this carbohydrate pattern, both recombinant human and murine PECAM-1-Ig chimeras were shown to bind S. Typhimurium in a dose-dependent manner in vitro. Using oral and fecal-oral transmission models of S. Typhimurium SL1344 infection, PECAM-1−/− mice were found to be more resistant to S. Typhimurium infection than wild-type (WT) C57BL/6 mice. While fecal shedding of S. Typhimurium was comparable in wild-type and PECAM-1−/− mice, the PECAM-1-deficient mice had lower bacterial loads in systemic organs such as liver, spleen, and mesenteric lymph nodes than WT mice, suggesting that extraintestinal dissemination was reduced in the absence of PECAM-1. This reduced bacterial load correlated with reduced tumor necrosis factor (TNF), interleukin-6 (IL-6), and monocyte chemoattractant protein (MCP) levels in sera of PECAM-1−/− mice. Following in vitro stimulation of macrophages with either whole S. Typhimurium, lipopolysaccharide (LPS) (Toll-like receptor 4 [TLR4] ligand), or poly(I·C) (TLR3 ligand), production of TNF and IL-6 by PECAM-1−/− macrophages was reduced. Together, these results suggest that PECAM-1 may have multiple functions in resistance to infection with S. Typhimurium, including binding to host cells, extraintestinal spread to deeper tissues, and regulation of inflammatory cytokine production by infected macrophages. PMID:23509149

  1. Expression of kidney injury molecule-1 (Kim-1) in relation to necrosis and apoptosis during the early stages of Cd-induced proximal tubule injury

    PubMed Central

    Prozialeck, Walter C.; Edwards, Joshua R.; Lamar, Peter C.; Liu, Jie; Vaidya, Vishal S.; Bonventre, Joseph V.

    2009-01-01

    Cadmium (Cd) is a nephrotoxic industrial and environmental pollutant that causes a generalized dysfunction of the proximal tubule. Kim-1 is a transmembrane glycoprotein that is normally not detectable in non-injured kidney, but is up-regulated and shed into the urine during the early stages of Cd-induced proximal tubule injury. The objective of the present study was to examine the relationship between the Cd-induced increase in Kim-1 expression and the onset of necrotic and apoptotic cell death in the proximal tubule. Adult male Sprague-Dawley rats were treated with 0.6 mg (5.36 μmoles) Cd/kg, subcutaneously, 5 days per week for up to 12 weeks. Urine samples were analyzed for levels of Kim-1 and the enzymatic markers of cell death, lactate dehydrogenase (LDH) and alpha-glutathione-S-transferase (α-GST). In addition, necrotic cells were specifically labeled by perfusing the kidneys in situ with ethidium homodimer using a procedure that has been recently developed and validated in the Prozialeck laboratory. Cryosections of the kidneys were also processed for the immunofluorescent visualization of Kim-1 and the identification of apoptotic cells by TUNEL labeling. Results showed that significant levels of Kim-1 began to appear in the urine after 6 weeks of Cd treatment, whereas the levels of total protein, α-GST and LDH were not increased until 8–12 weeks. Results of immunofluorescence labeling studies showed that after 6 weeks and 12 weeks, Kim-1 was expressed in the epithelial cells of the proximal tubule, but that there was no increase in the number of necrotic cells, and only a modest increase in the number of apoptotic cells at 12 weeks. These results indicate that the Cd-induced increase in Kim-1 expression occurs before the onset of necrosis and at a point where there is only a modest level of apoptosis in the proximal tubule. PMID:19371613

  2. Combined Treatment with Amlodipine and Atorvastatin Calcium Reduces Circulating Levels of Intercellular Adhesion Molecule-1 and Tumor Necrosis Factor-α in Hypertensive Patients with Prediabetes

    PubMed Central

    Huang, Zhouqing; Chen, Chen; Li, Sheng; Kong, Fanqi; Shan, Peiren; Huang, Weijian

    2016-01-01

    Objective: To assess the effect of amlodipine and atorvastatin on intercellular adhesion molecule (ICAM)-1 and tumor necrosis factor (TNF)-α expression, as endothelial function and inflammation indicators, respectively, in hypertensive patients with and without prediabetes. Methods: Forty-five consecutive patients with hypertension, diagnosed according to JNC7, were divided into two groups based on the presence (HD group, n = 23) or absence (H group, n = 22) of prediabetes, diagnosed according to 2010 ADA criteria, including impaired glucose tolerance (IGT) and fasting glucose tests. All patients simultaneously underwent 12-week treatment with daily single-pill amlodipine besylate/atorvastatin calcium combination (5/10 mg; Hisun-Pfizer Pharmaceuticals Co. Ltd). Serum isolated before and after treatment from overnight fasting blood samples was analyzed by ELISA. Results: In the HD and H groups after vs. before 12-week amlodipine/atorvastatin treatment, there were significantly (all P < 0.01) lower levels of ICAM-1 (3.06 ± 0.34 vs. 4.07 ± 0.70 pg/ml; 3.26 ± 0.32 vs. 3.81 ± 0.60 pg/ml, respectively) and TNF-α (78.71 ± 9.19 vs. 110.94 ± 10.71 pg/ml; 80.95 ± 9.33 vs. 101.79 ± 11.72 pg/ml, respectively), with more pronounced reductions in HD vs. H group (ICAM-1Δ: 1.01 ± 0.80 vs. 0.55 ± 0.64 pg/ml, respectively, P = 0.037; TNF-αΔ: 32.23 ± 14.33 vs. 20.84 ± 14.89 pg/ml, respectively, P = 0.011), independent of the blood pressure (BP) and cholesterol level reduction. Conclusions: Amlodipine/atorvastatin improved endothelial function and inflammation, as reflected by lower circulating levels of ICAM-1 and TNF-α, more prominently in hypertensives with than without prediabetes. Starting statin treatment before overt diabetes in hypertensives might thus improve cardiovascular outcomes. PMID:27610083

  3. Triamcinolone acetonide modulates permeability and intercellular adhesion molecule-1 (ICAM-1) expression of the ECV304 cell line: implications for macular degeneration.

    PubMed

    Penfold, P L; Wen, L; Madigan, M C; Gillies, M C; King, N J; Provis, J M

    2000-09-01

    Whilst animal studies and a pilot clinical trial suggest that intravitreal triamcinolone acetonide (TA) may be useful in the treatment of age-related macular degeneration (AMD), its mode of action remains to be fully elucidated. The present study has investigated the capacity of TA to modulate the expression of adhesion molecules and permeability using a human epithelial cell line (ECV304) as a model of the outer blood-retinal barrier (BRB). The influence of TA on the expression of ICAM-1 and MHC-I was studied on resting and phorbol myristate acetate (PMA)- or interferon-gamma (IFN-gamma)- and/or tumour necrosis factor-alpha (TNF-alpha)-activated cells using flow cytometry and immunocytochemistry. Additionally, ECV304 cells were grown to confluence in uncoated Transwell chambers; transepithelial resistance (TER) across resting and PMA-activated cells was monitored. TA significantly decreased the paracellular permeability of ECV304 cells and down-regulated ICAM-1 expression, consistent with immunocytochemical observations. PMA-induced permeability changes were dose-dependent and TA decreased permeability of both resting and PMA-activated monolayers. MHC-I expression by ECV304 cells however, was not significantly affected by TA treatment. The modulation of TER and ICAM-1 expression in vitro correlate with clinical observations, suggesting re-establishment of the BRB and down-regulation of inflammatory markers are the principal effects of intravitreal TA in vivo. The results further indicate that TA has the potential to influence cellular permeability, including the barrier function of the retinal pigment epithelium (RPE) in AMD-affected retinae.

  4. Effects of anti-tumor necrosis factor-alpha and anti-intercellular adhesion molecule-1 antibodies on ischemia/reperfusion lung injury.

    PubMed

    Chiang, Chi-Huei

    2006-10-31

    Inhibition of neutrophil activation and adherence to endothelium by antibodies to tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecules (ICAM-1), respectively, might attenuate ischemia-reperfusion injury (I/R). I/R was conducted in an isolated rat lung model. Anti-TNF-alpha antibody and/or anti-ICAM-1 antibody were added before ischemia or after reperfusion. Hemodynamic changes, lung weight gain (LWG), capillary filtration coefficients (Kfc), and pathologic changes were assessed to evaluate the severity of I/R. The LWG, Kfc, pathological changes and lung injury score of treatment groups with anti-TNF-alpha antibody treatment, either pre-ischemia or during reperfusion, were less than those observed in control groups. Similar findings were found in group treated with anti-ICAM-1 antibody or combination therapy during reperfusion. In contrast, pre-I/R treatment with anti-ICAM-1 antibody induced severe lung edema and failure to complete the experimental procedure. No additional therapeutic effect was found in combination therapy. We conclude that TNF-alpha and ICAM-1 play important roles in I/R. Anti-TNF-alpha antibody has therapeutic and preventive effects on I/R. However, combined therapy with anti-TNF-alpha antibody and anti-ICAM-1 antibody may have no additive effect and need further investigation.

  5. Ligand-induced adhesion to activated endothelium and to vascular cell adhesion molecule-1 in lymphocytes transfected with the N-formyl peptide receptor.

    PubMed

    Honda, S; Campbell, J J; Andrew, D P; Engelhardt, B; Butcher, B A; Warnock, R A; Ye, R D; Butcher, E C

    1994-04-15

    Binding of FMLP to the neutrophil N-formyl peptide receptor (FPR) transmits signals through pertussis toxin-sensitive G proteins triggering Ca2+ flux, superoxide production, granule exocytosis, and neutrophil aggregation and adhesion involving the beta 2 (CD18) integrins. Expression of the FPR in mouse fibroblasts or human kidney cells has been shown to confer an N-formyl peptide-inducible Ca2+ flux in transfectants. Here we demonstrate that the transfected receptor can also support ligand-induced alterations in cellular adhesion. We established stable transfectants of mouse L1-2 pre-B cells with cDNA for human FPR (L1-2 FPR cells). The transfectants bind N-formyl-Nle-Leu-Phe-Nle-Tyr-Lys-fluorescein with 1.4 x 10(5) sites per cell and a dissociation constant of 3.3 nM. Stimulation with FMLP induces a transient Ca2+ flux. FMLP also triggers adhesion of L1-2 FPR cells to TNF-alpha- or LPS-activated bEnd3 cells (mouse brain-derived endothelial cells) and to purified mouse VCAM-1. Binding is inhibited by Abs to VCAM-1 and to the alpha-chain of its lymphocyte receptor (the alpha 4 beta 1 integrin, VLA-4). Stimulation with FMLP does not induce a change in cell surface expression of alpha 4. Induced adhesion to VCAM-1 is rapid, detectable at the earliest times measurable (30 to 60 s after FMLP addition), and is inhibited by pertussis toxin. We conclude that FPR can mediate integrin activation not only in neutrophils but also in lymphocytes, and can trigger rapid adhesion via lymphocyte alpha 4 beta 1. The adhesion of lymphocytes is critical to their migration and targeting; our results suggest the possibility of manipulating adhesive responses through expression of chemoattractant receptors in lymphoid cells engineered for cellular therapy, allowing targeted adhesion and potentially migration in response to locally administered ligands.

  6. Leu125Val polymorphism of platelet endothelial cell adhesion molecule-1 is associated with atherosclerotic cerebral infarction in Chinese Han population.

    PubMed

    Song, Yanmin; Zhao, Ranran; Long, Lili; Zhang, Ning; Liu, Yunhai

    2014-01-01

    A total of 142 Atherosclerotic cerebral infarction (ACI) patients and 116 controls were enrolled in our study. The Leu125Val polymorphism of PECAM-1 was genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The plasma sPECAM-1 level was measured by enzyme-linked immunosorbent assay (ELISA) method. We found a statistically significant difference in Leu125Val genotypic distribution between cases and controls (P < 0.05). The frequencies of the Val allele between ACI group and controls were significantly different (P < 0.05). Logistic regression analysis showed that the genotype Val/Val was associated with increased ACI risk (OR = 2.355, 95% CI = 1.153-4.809, P = 0.019). In both the ACI group and the control group, the plasma PECAM-1 levels of carriers of the Val/Val genotype were higher than those carrying Leu/Leu and Leu/Val genotypes. The plasma sPECAM-1 level is associated with ACI. Our study showed that Leu125Val polymorphism of PECAM-1 may be associated with ACI risk. Carrying the Val/Val genotype showed increased risk for ACI. The Leu125Val polymorphism of PECAM-1 may be associated with the plasma sPECAM-1 level, which is associated with Chinese ACI also. In conclusions, The Leu125Val polymorphism of the PECAM-1 gene is likely to be related to ACI, and the Val/Val genotype may be an independent risk factor for ACI. The plasma sPECAM-1 level may be associated with ACI risk.

  7. Neisserial outer membrane vesicles bind the coinhibitory receptor carcinoembryonic antigen-related cellular adhesion molecule 1 and suppress CD4+ T lymphocyte function.

    PubMed

    Lee, Hannah S W; Boulton, Ian C; Reddin, Karen; Wong, Henry; Halliwell, Denise; Mandelboim, Ofer; Gorringe, Andrew R; Gray-Owen, Scott D

    2007-09-01

    Pathogenic Neisseria bacteria naturally liberate outer membrane "blebs," which are presumed to contribute to pathology, and the detergent-extracted outer membrane vesicles (OMVs) from Neisseria meningitidis are currently employed as meningococcal vaccines in humans. While the composition of these vesicles reflects the bacteria from which they are derived, the functions of many of their constituent proteins remain unexplored. The neisserial colony opacity-associated Opa proteins function as adhesins, the majority of which mediate bacterial attachment to human carcinoembryonic antigen-related cellular adhesion molecules (CEACAMs). Herein, we demonstrate that the Opa proteins within OMV preparations retain the capacity to bind the immunoreceptor tyrosine-based inhibitory motif-containing coinhibitory receptor CEACAM1. When CD4(+) T lymphocytes were exposed to OMVs from Opa-expressing bacteria, their activation and proliferation in response to a variety of stimuli were effectively halted. This potent immunosuppressive effect suggests that localized infection will generate a "zone of inhibition" resulting from the diffusion of membrane blebs into the surrounding tissues. Moreover, it demonstrates that OMV-based vaccines must be developed from strains that lack CEACAM1-binding Opa variants.

  8. BLOOD LEUKOCYTE EXPRESSION OF LFA-1 AND INTRACELLULAR ADHESION MOLECULE-1 (ICAM-1) AFTER INHALATION OF ULTRAFINE CARBON PARTICLES. (R827354C003)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  9. Expression of kidney injury molecule-1 (Kim-1) in relation to necrosis and apoptosis during the early stages of Cd-induced proximal tubule injury

    SciTech Connect

    Prozialeck, Walter C. Edwards, Joshua R.; Lamar, Peter C.; Liu, Jie; Vaidya, Vishal S.; Bonventre, Joseph V.

    2009-08-01

    Cadmium (Cd) is a nephrotoxic industrial and environmental pollutant that causes a generalized dysfunction of the proximal tubule. Kim-1 is a transmembrane glycoprotein that is normally not detectable in non-injured kidney, but is up-regulated and shed into the urine during the early stages of Cd-induced proximal tubule injury. The objective of the present study was to examine the relationship between the Cd-induced increase in Kim-1 expression and the onset of necrotic and apoptotic cell death in the proximal tubule. Adult male Sprague-Dawley rats were treated with 0.6 mg (5.36 {mu}mol) Cd/kg, subcutaneously, 5 days per week for up to 12 weeks. Urine samples were analyzed for levels of Kim-1 and the enzymatic markers of cell death, lactate dehydrogenase (LDH) and alpha-glutathione-S-transferase ({alpha}-GST). In addition, necrotic cells were specifically labeled by perfusing the kidneys in situ with ethidium homodimer using a procedure that has been recently developed and validated in the Prozialeck laboratory. Cryosections of the kidneys were also processed for the immunofluorescent visualization of Kim-1 and the identification of apoptotic cells by TUNEL labeling. Results showed that significant levels of Kim-1 began to appear in the urine after 6 weeks of Cd treatment, whereas the levels of total protein, {alpha}-GST and LDH were not increased until 8-12 weeks. Results of immunofluorescence labeling studies showed that after 6 weeks and 12 weeks, Kim-1 was expressed in the epithelial cells of the proximal tubule, but that there was no increase in the number of necrotic cells, and only a modest increase in the number of apoptotic cells at 12 weeks. These results indicate that the Cd-induced increase in Kim-1 expression occurs before the onset of necrosis and at a point where there is only a modest level of apoptosis in the proximal tubule.

  10. Green tea polyphenol epigallocatechin-3-gallate attenuates TNF-α-induced intercellular adhesion molecule-1 expression and monocyte adhesion to retinal pigment epithelial cells.

    PubMed

    Thichanpiang, Peeradech; Wongprasert, Kanokpan

    2015-01-01

    Epigallocatechin-3-gallate (EGCG) is a major polyphenol component of green tea (Camellia sinensis) and demonstrates anti-oxidant, anticancer and anti-inflammatory properties. EGCG has been shown to protect retinal pigment epithelium (RPE) against oxidative stress-induced cell death. The pathogenesis of diseases in the retina is usually initiated by local inflammation at the RPE cell layer, and inflammation is mostly associated with leukocyte migration and the secretion of pro-inflammatory cytokines. Whether EGCG can modulate the cytokine-induced inflammatory response of RPE, particularly leukocyte migration, has not been clearly elucidated, and was therefore the objective of this study. ARPE-19 cells were cultured with different concentrations of TNF-α in the presence or absence of EGCG to different time points. Intracellular reactive oxygen species (ROS) levels were determined. Intercellular adhesion molecule (ICAM)-1 and phosphor-NF-κB and IκB expression were determined by Western blot analysis. Phosphor-NF-κB nuclear translocation and monocyte-RPE adhesion were investigated using immunofluorescence confocal laser scanning microscopy. Scanning electron microscopy (SEM) was carried out to further determine the ultrastructure of monocyte-RPE adhesion. The results demonstrated that TNF-α modulated inflammatory effects in ARPE-19 by induction of ROS and up-regulation of ICAM-1 expression. Moreover, TNF-α-induced phosphor-NF-κB nuclear translocation, increased phosphor-NF-κB expression and IκB degradation, and increased the degree of monocyte-RPE adhesion. Pretreating the cells with EGCG ameliorated the inflammatory effects of TNF-α. The results indicated that EGCG significantly exerts anti-inflammatory effects in ARPE-19 cells, partly as a suppressor of TNF-α signaling and that the inhibition was mediated via the NF-κB pathway.

  11. Association of Polymorphisms in Intercellular Adhesion Molecule 1 (ICAM-1) Gene with Cancer Susceptibility: A Meta-Analysis of 14 Case-Control Studies.

    PubMed

    Zhang, Xiaolong; Huang, Junjie; Bai, Jian; Lu, Wei; Zhang, Meng; Mei, Hongbing

    2016-02-21

    BACKGROUND Many epidemiology studies have indicated that polymorphisms in ICAM-1 are associated with a variety of cancers, but published data are contradictory and inconclusive. Therefore, we conducted the current meta-analysis to elaborate the effects of ICAM-1 polymorphisms (rs5491, rs3093030, rs281432, and rs1799969) on cancer susceptibility. MATERIAL AND METHODS We conducted a comprehensive literature search in PubMed, Web of Science, and Google Scholar. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association between ICAM-1 polymorphisms and cancer susceptibility. RESULTS We enrolled 14 published case-control studies including 4608 cancer cases and 4913 controls. We found an increased susceptibility of cancer in polymorphism rs1799969 (C vs. T: OR=1.662, 95%CI=1.288-2.143, p=0141; CT vs. TT: OR=1.860, 95%CI=1.398-2.474, p=0.507; CC+CT vs. TT: OR=1.812, 95%CI=1.373-2.391, p=0.284) of ICAM-1 among the overall population. However, no association between polymorphisms rs5491, rs3093030, or rs281432 of ICAM-1 and cancer susceptibility was identified. In the stratification analysis by ethnicity, we identified an increased susceptibility for Asians in rs3093030 polymorphism (CC vs. TC+TT: OR=1.728, 95% CI=1.234-2.421, p=0.787). CONCLUSIONS Our results suggest that the ICAM-1 polymorphism rs1799969 is significantly associated with increased susceptibility to overall cancer. Further studies (preferably prospective) are warranted to validate these relationships.

  12. Professionals Working Together. Proceedings of the Annual Meeting of the Association of Physical Plant Administrators of Universities and Colleges (72nd, San Diego, California, July 10-13, 1985).

    ERIC Educational Resources Information Center

    Association of Physical Plant Administrators of Universities and Colleges, Washington, DC.

    Issues concerning the conditions of college facilities are considered in 29 papers from the 1985 annual meeting of the Association of Physical Plant Administrators of Universities and Colleges. Papers and authors include: "Crumbling Academe" (Harvey H. Kaiser); "Physical Facilities Evaluation" (Henry L. Shelby); "Managing…

  13. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Mass Communication and Society Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The mass communication and society section of the Proceedings contains the following 17 papers: "Deviance in News Coverage of On-Line Communications: A Print Media Comparison" (Lisa M. Weidman); "Political Tolerance of Environmental Protest: The Roles of Generalized and Specialized Information" (Catherine A. Steele and Carol M.…

  14. Molecular Biology and Functions of Carrier Proteins. Annual Symposium (46th) of the Society of General Physiologists held in Woods Hole, Massachusetts on September 10-13, 1992. Volume 48

    DTIC Science & Technology

    1993-09-13

    Naý/H+ exchanger I ( NHE1 ) isoform, which appears to be expressed in every cell system where it has been investigated (for review, see Grinstein. 1988...amiloride. The discovery that NHE1 is rapidly turned on by all known mitogens has initiated many studies trying to elucidate both the contribution of this...antiporter in the control of cell proliferation and the cellular signaling pathways leading to NHE1 activation (for review. see Grinstein et al.. 1989

  15. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part VII: Media and Politics.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Media and Politics section of this collection of conference proceedings contains the following 11 papers: "Characteristics of Readers of Religious Publications for Political Information" (Judith M. Buddenbaum); "Is 'Nightline' Biased?: A Content Analysis of the Issue of Gays in the Military" (Chuck Hoy and Terry Scott);…

  16. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part VI: Mass Media Effects.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Mass Media Effects section of this collection of conference presentations contains the following 13 papers: "The Nature of the Public's Objections to Television Programs: An Examination of Third-Person Effects" (Guy E. Lometti and others); "An Examination of the Relationship of Structural Pluralism, News Role and Source Use with…

  17. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part VIII: Advertising and Public Relations.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Advertising and Public Relations section of this collection of conference presentations contains the following 17 papers: "Using the FCB Grid and the 'Lost Quadrants' to Write Advertising Strategy" (Johan C. Yssel); "Antitrust and the Marketplace of Ideas: The Continuing Problem of Issue Advertising Access to Broadcast…

  18. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Status of Women and Minorities and Communication Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Status of Women and Minorities and Communication section of the proceedings contains the following 14 papers: "Who Harasses Women Journalists? A Qualitative Look at Sexual Harassment among U.S. Newswomen" (Kim Walsh-Childers and others); "Not There Yet--Coverage of Women in Foreign News: A 1995 Multi-National Study" (Anat…

  19. Fault Tolerant Design Concepts for Highly Integrated Flight Critical Guidance and Control Systems: Conference Proceedings Held at the Guidance and Control Panel Symposium (49th) Held in Toulouse, France on 10-13 October 1989

    DTIC Science & Technology

    1990-04-01

    utilisant la meilleure automatisation: les iliments capteurs , les calculateurs et les informations sur lNtat du systime conditionnent le succ6s. La...je suis ameni tout naturellement i vous prisenter d’autres contraintes: lea contraintes humaines qui doivent Etre prises en consideration. Au niveau...do calculaturs, do capteurs do Ia position do lavlon (centralos & Inertie ot barom~triquos, accdl6rombtres), of dractonneura. Los calculateura

  20. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Communication Theory and Methodology Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The communication theory and methodology section of the Proceedings contains the following 20 papers: "Political Adwatches and the Third-Person Effect" (Ekaterina Ognianova and others); "Understanding Adopters of Audio Information Services" (Kimberly A. Neuendorf and others); "A Principal-Agent Approach to the Study of…

  1. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Advertising and Public Relations Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Advertising and Public Relations section of the proceedings contains the following 14 papers: "Toward an Understanding of Cultural Values Manifest in Advertising: A Content Analysis of Chinese Television Commercials from 1990 and 1995" (Hong Cheng); "The Impact of Advertising Distance on International Advertising: An Analysis of…

  2. Quality Programming in H.P.E.R. Selected Papers Presented at the Convention of the Canadian Association for Health, Physical Education and Recreation (British Columbia, Canada, June 10-13, 1981). Physical Education Series Number 2.

    ERIC Educational Resources Information Center

    Jackson, John J., Ed.; Turkington, H. David, Ed.

    These papers, presented during the 1981 convention of the Canadian Association for Health, Physical Education and Recreation, addressed eight major topics: (1) the physical education and sport profession in Canada; (2) physical fitness (community agencies, radiology, aging and physical activity, the effective physical education program, aerobic…

  3. Clear cutting (10-13th century) and deep stable economy (18-19th century) as responsible interventions for sand drifting and plaggic deposition in cultural landscapes on aeolian sands (SE-Netherlands).

    NASA Astrophysics Data System (ADS)

    van Mourik, Jan; Vera, Hein; Wallinga, Jakob

    2013-04-01

    The landscape in extensive areas in SE-Netherlands is underlain by coversand, deposited during the Late Glacial of the Weichselian. In the Preboreal, aeolian processes reduced soil formation. From the Preboreal to the Atlantic a deciduous climax forest developed. The geomorphology was a coversand landscape, composed of ridges (umbric podzols), coversand plains (gleyic podzols), coversand depressions (histic podzols) and small valleys (gleysols). The area was used by hunting people during the Late Paleolithic and Mesolithic. During the Bronze and Iron Ages the area was populated by people, living from forest grazing, shifting cultivation and trade. The natural deciduous forest gradually degraded into Calluna heath. The deforestation accelerated the soil acidification and affected the hydrology, which is reflected in drying out of ridges and wetting of depressions, promoting the development of histic podzols and even histosols. Aeolian erosion was during this period restricted to local, small scale sand drifting, related to natural hazards as forest fires and hurricanes and shifting cultivation. Sustainable crop productivity on chemically poor sandy substrates required application of organic fertilizers, composed of a mixture of organic litter and animal manure with a very low mineral compound, produced in shallow stables. At least since 1000 AD, heath management was regulated by a series of rules that aimed to protect the valuable heat lands against degradation. During the 11th, 12th and 13th centuries there was an increasing demand for wood and clear cutting transformed the majority of the forests in driftsand landscapes. The most important market was formed by the very wealthy Flemish cities. The exposed soil surface was subjected to wind erosion and sand drifting which endangered the Calluna heath, arable land and even farmhouses. As a consequence, umbric podzols, the natural climax soil under deciduous forests on coversand, degraded into larger scale driftsand landscapes, characterized by deflation plains (gleyic arenosols) and complexes of inland dunes (haplic arenosols). Clear cutting was responsible for the mediaeval first large scale expansion of drift sand landscapes. In such driftsand landscapes, the majority of the podzolic soils in coversand has been truncated by aeolian erosion. Only on scattered sheltered sites in the landscape, palaeopodzols were buried under mono or polycyclic driftsand deposits. They are now the valuable soil archives for palaeoecological research. During the 18th century, the population growth and regional economic activity stimulated the agricultural productivity. Farmers introduced the innovative 'deep stable' technique to increase the production of fertilizers. Farmers started sod digging, including the top of the Ah horizon of the humus forms. This consequently promoted heath degradation and sand drifting, resulting in the extension of driftsand landscapes. Deep stable economy and sod digging was responsible for the 18th century second large scale expansion of drift sand landscapes. During the 19th century, farmers tried to find alternative fertilizers and authorities initiated reforestation projects. The invention of chemical fertilizers at the end of the 19th century marked the end of the period of heath management and plaggic agriculture. The heath was no longer used for the harvesting of plaggic matter and new land management practices were introduced. Heath was reclaimed to new arable land or reforested with Scotch pine. Geomorphological features as inland dunes and plaggic covers survived in the landscape and are now included in the geological inheritance.

  4. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part V: Media and Technology.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Media and Technology section of this collection of conference presentations contains the following 10 papers: "Carpooling on the Information Superhighway" (Lorna Veraldi); "New Media Departure in 'The Principle of Relative Constancy': VCRs" (Ghee-Young Noh); "Why the Western Design Approach Does Not Work for Asian…

  5. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (77th, Atlanta, Georgia, August 10-13, 1994). Part II: Media and Law.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Media and Law section of this collection of conference presentations contains the following 11 papers: "Independent State Constitutional Analysis of Public Concern and Opinion Issues in Defamation Litigation, 1977-1993" (James Parramore); "The President John F. Kennedy Assassination Records Collection Act of 1992: Will Sun…

  6. Setting the Pace for Professionalism. Proceedings of the Annual Meeting of the Association of Physical Plant Administrators of Universities and Colleges (70th, Louisville, Kentucky, July 10-13, 1983).

    ERIC Educational Resources Information Center

    Association of Physical Plant Administrators of Universities and Colleges, Washington, DC.

    Professionalism in the management and operations of the physical plant at universities and colleges is addressed in the 30 papers published in this Proceedings, which contains all the presentations made at the 1983 meeting. Papers and authors include the following: "Evaluation of Single-Ply Roof Systems" (Mark D. Langford, Steve Wolff);…

  7. Proceedings of the First International Symposium on the Interaction of Non-Nuclear Munitions with Structures: Held at U.S. Air Force Academy, Colorado on May 10-13, 1983. Part 1.

    DTIC Science & Technology

    1983-05-01

    fibre- Fibres reinforced concrete would be applied over a large area, hence it was coni~odered vital that local end Since it is impractical to include...iging from 26.2 .IPa to 26 MPa and unconfined has been monitored by means of a Linear Variable teisile strength (f ) of 4.1 MP&s were initially...notched specimen. The un-notched spei- h men was subjected to a small unloading.-reloading cycle at approx. 702 of peak strength and signO - 3 ficant

  8. Di-μ-azido-bis­(μ-1,4,7,10,13,16-hexa­oxacyclo­octa­deca­ne)bis­(5,10,15,20-tetra­phenyl­porphyrinato)dicadmium­disodium

    PubMed Central

    Toumi, Hamza; Amiri, Nesrine; Belkhiria, Mohamed Salah; Daran, Jean-Claude; Nasri, Habib

    2012-01-01

    The asymmetric unit of the title compound, [Cd2Na2(N3)2(C44H28N4)2(C12H24O6)2], consists of one half of the dimeric complex; the tetra­nuclear mol­ecule lies about an inversion centre. The CdII atom is coordinated by the four pyrrole N atoms of the 5,10,15,20-tetra­phenyl­porphyrinate ligand and one N atom of the axial azide ligand in a square-pyramidal geometry. The azide group is also linked to the NaI atom, which is surrounded by one 18-crown-6 molecule and additionally bonded to a second 18-crown-6 molecule trans to the azide group. The porphyrin core exhibits a major doming distortion (∼40%) and the crystal structure is stabilized by weak C—H⋯π inter­actions. The mol­ecular structure features weak intra­molecular hydrogen bonds: two O—H⋯O inter­actions within the 18-crown-6 mol­ecule and one C—H(18-crown-6)⋯N(azido) contact. PMID:23468761

  9. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (79th, Anaheim, CA, August 10-13, 1996). Visual Communication and Science and Health Communication Division.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Visual Communication and Science and Health Communication section of the proceedings contains the following 12 papers: "The Designers' Toolbox: Newsroom Experience and Ideal Characteristics of Newspaper Designers" (Wayne Wanta and Lauren Danner); "Patterned Image of the Homeless: Discourse Analysis of Television News…

  10. Proceedings of the First International Symposium on the Interaction of Non-Nuclear Munitions with Structures Held at U.S. Air Force Academy, Colorado on May 10-13, 1983. Part 2

    DTIC Science & Technology

    1983-05-13

    Armor HY80 Steel Steel 500 - 3500 0 - 70 i HY100 Steel Steel 500 - 3000 0 - 70 j Mild Steel Steel 500 - 3000 0 - 45 k 5083, 7039, Ti Steel 500 - 3000...POOl 754 Interaction of High Velocity Aluminum Shaped Charge lets with Finite Steel and Concrete Targets. AD-POOl 755 Penetration Equation from Steel ...of Protective Design" (Non-Nuclear). AD-POOl 764 Model Law for Concrete Structure Under Lynamic Loads. kD-POOl 765 Response of Drag-Sensitive, Steel

  11. Winner of the 2013 Young Investigator Award for the Society for Biomaterials annual meeting and exposition, April 10-13, 2013, Boston, Massachusetts. Osteogenic differentiation of mesenchymal stem cells on demineralized and devitalized biodegradable polymer and extracellular matrix hybrid constructs.

    PubMed

    Thibault, Richard A; Mikos, Antonios G; Kasper, F Kurtis

    2013-05-01

    Devitalization and demineralization processing of biodegradable polymer and extracellular matrix (ECM) hybrid constructs was explored for the effect on the retention of ECM components and construct osteogenicity. Hybrid constructs were generated by seeding osteogenically predifferentiated rat mesenchymal stem cells (MSCs) onto electrospun poly(ε-caprolactone) fiber meshes and culturing in osteogenic medium for 12 or 16 days within a flow perfusion bioreactor to create an ECM coating. The resulting constructs were then either devitalized (using a freeze-thaw or a detergent technique), devitalized and demineralized, or left untreated, and subsequently characterized for DNA, glycosaminoglycan, collagen, and calcium content. The osteogenicity of each construct was investigated by culturing MSCs on the hybrid constructs within a flow perfusion bioreactor for 4, 8, and 12 days in osteogenic medium. Histological staining demonstrated that devitalization via the freeze-thaw method retained the thickest coating of ECM components within the constructs. Demineralization and devitalization processing of ECM coated constructs resulted in a decrease in their osteogenicity.

  12. Research in Science Education, 1994. Selected Refereed Papers from the Annual Conference of the Australasian Science Education Research Association (25th, Hobart, Tasmania, Australia, July 10-13, 1994).

    ERIC Educational Resources Information Center

    Gardner, Paul L., Ed.

    1994-01-01

    This volume contains 41 papers, 10 abstracts/research notes, and an after-dinner speech "The Book of Genesis and the Chronicles of the People of ASERA (Australasian Science Education Research Association). Paper titles include: "Improving students' understanding of carbohydrate metabolism in first-year Biochemistry at tertiary…

  13. Technical Evaluation Report on the Guidance and Control Panel Symposium on Fault Tolerant Design Concepts for Highly Integrated Flight Critical Guidance and Control Systems (49th) Held in Toulouse, France on 10-13 October 1989

    DTIC Science & Technology

    1990-05-01

    critical concepts for low-level tactical operation with autonomous , accurate target acquisition ; the discussion is based on the close Air Support...Further discussions are the topics of paper n’ 53. On-board expert system to support aircraft diagnostics and vehicule management system to support...and environment monitoring. Session IV Paper 41 . A HIGHLY RELIABLE, AUTONOMOUS DATA COMMUNICATION SUBSYSTEM FOR AN ADVANCED INFORMATION PROCESSING

  14. Preparing for a New Century of Learning: Technology, Education, and the Internet. ICTE Tampa 1999: International Conference on Technology and Education Proceedings (17th, Tampa, Florida, October 10-13, 1999).

    ERIC Educational Resources Information Center

    1999

    The overarching focus of the International Conference on Technology and Education (ICTE) Tampa 1999 conference was "Preparing for a New Century of Learning: Technology, Education, and the Internet." Twelve themes supported this focus: "Implementation in the Classroom"; "Educational Tools"; "Information Technology…

  15. International Aerospace and Ground Conference on Lightning and Static Electricity (ICOLSE) (10th) and the Congres International Aeronautiq (17th) Held in Paris (France) on 10-13 June 1985

    DTIC Science & Technology

    1985-06-13

    est principalement axee sur l’emploi ä grande echelle de materiaux composites et 1’ utilisation d’une electronique omnipresente, appelee ä traiter...I’assemblage de ses elements constitutifs, les materiaux utilises et les cheminements de ses circuits elect riques sont d’ores et dejä informatises. La...Electrification", J. Geophys. Res., 55, 473-484, 1980. Gondot, P., "Definition et exploitation de capteurs destines a la mesure de la conductivity glectrique

  16. Atmospheric lifetimes, infrared spectra and degradation products of a series of hydrofluoroethers

    NASA Astrophysics Data System (ADS)

    Cavalli, F.; Glasius, M.; Hjorth, J.; Rindone, B.; Jensen, N. R.

    The rate constants of the reactions between the OH radical and a series of hydrofluoroethers (HFE) have been measured. The reaction of OH with CHF 2OCF 2OCHF 2 (1), CHF 2OCF 2CF 2OCHF 2 (2), CHF 2OCF 2CF 2OCF 2OCHF 2 (3) and CH 3OC 4F 9 (4) were investigated at 295±3 K and 740±5 Torr total pressure. The following values of the rate constants were determined for the reaction with the OH radical: k1=(2.4±0.7)×10 -15 cm 3 molecule -1 s -1, k2=(4.7±1.6)×10 -15 cm 3 molecule -1 s -1, k3=(4.6±1.6)×10 -15 cm 3 molecule -1 s -1 and k4=(7.2±1.6)×10 -15 cm 3 molecule -1 s -1. (All values are given with 2 σ uncertainties). Infrared spectra were obtained for all four HFEs in the range from 600 to 4000 cm -1 (3 to 17 μm), with the following IBI-values (integrated band intensities): IBI 1= (5.19±0.23)×10 -16 cm molecule -1 for the 978-1584 cm -1 band, IBI 2=(6.04±0.13)×10 -16 cm molecule -1 for the 930-1501 cm -1 band, IBI 3=(8.49±0.34)×10 -16 cm molecule -1 from the 963-1587 cm -1 band and IBI 4=(4.23±0.14)×10 -16 cm molecule -1 for the 845-1428 cm -1 band. Carbonyl fluoride, CF 2O, was the only fluorine-containing degradation product that was found from the Cl atom-initiated reactions of both CHF 2OCF 2OCF 2CF 2OCHF 2 and CH 3OC 4F 9, with measured product yields of 60-97% and 20-40% (based on carbon atoms), respectively. Due to the high uptake parameter of CF 2O to liquid water, its lifetime in the atmosphere is very short (with an upper limit between 15 and 30 d). It is rapidly incorporated into raindrops/aerosols, where it eventually degrades to HF and CO 2. The GWP of CF 2O is therefore negligible compared to those of CFC-11 and CFC-12.

  17. O2(a1Δg) + Mg, Fe, and Ca: Experimental kinetics and formulation of a weak collision, multiwell master equation with spin-hopping

    NASA Astrophysics Data System (ADS)

    Plane, J. M. C.; Whalley, C. L.; Frances-Soriano, L.; Goddard, A.; Harvey, J. N.; Glowacki, D. R.; Viggiano, A. A.

    2012-07-01

    The first excited electronic state of molecular oxygen, O2(a1Δg), is formed in the upper atmosphere by the photolysis of O3. Its lifetime is over 70 min above 75 km, so that during the day its concentration is about 30 times greater than that of O3. In order to explore its potential reactivity with atmospheric constituents produced by meteoric ablation, the reactions of Mg, Fe, and Ca with O2(a) were studied in a fast flow tube, where the metal atoms were produced either by thermal evaporation (Ca and Mg) or by pulsed laser ablation of a metal target (Fe), and detected by laser induced fluorescence spectroscopy. O2(a) was produced by bubbling a flow of Cl2 through chilled alkaline H2O2, and its absolute concentration determined from its optical emission at 1270 nm (O2(a1Δg - X3Σg-). The following results were obtained at 296 K: k(Mg + O2(a) + N2 → MgO2 + N2) = (1.8 ± 0.2) × 10-30 cm6 molecule-2 s-1; k(Fe + O2(a) → FeO + O) = (1.1 ± 0.1) × 10-13 cm3 molecule-1 s-1; k(Ca + O2(a) + N2 → CaO2 + N2) = (2.9 ± 0.2) × 10-28 cm6 molecule-2 s-1; and k(Ca + O2(a) → CaO + O) = (2.7 ± 1.0) × 10-12 cm3 molecule-1 s-1. The total uncertainty in these rate coefficients, which mostly arises from the systematic uncertainty in the O2(a) concentration, is estimated to be ±40%. Mg + O2(a) occurs exclusively by association on the singlet surface, producing MgO2(1A1), with a pressure dependent rate coefficient. Fe + O2(a), on the other hand, shows pressure independent kinetics. FeO + O is produced with a probability of only ˜0.1%. There is no evidence for an association complex, suggesting that this reaction proceeds mostly by near-resonant electronic energy transfer to Fe(a5F) + O2(X). The reaction of Ca + O2(a) occurs in an intermediate regime with two competing pressure dependent channels: (1) a recombination to produce CaO2(1A1), and (2) a singlet/triplet non-adiabatic hopping channel leading to CaO + O(3P). In order to interpret the Ca + O2(a) results, we

  18. The Br+HO 2 reaction revisited: Absolute determination of the rate constant at 298 K

    NASA Astrophysics Data System (ADS)

    Laverdet, G.; Le Bras, G.; Mellouki, A.; Poulet, G.

    1990-09-01

    The absolute determination of the rate constant for the reaction Br+HO 2→HBr+O 2 has been done at 298 K using the discharge-flor EPR method. The value k1 = (1.5±0.2) × 10 -12 cm 3 molecule -1 s -1 was obtained. Previous indirect measurements of k1 from a discharge-flow, LIF/mass spectrometric study of the Br/H 2CO/O 2 system have been reinterpreted, leading to values for k1 ranging from 1.0 × 10 -12 to 2.2 × 10 -12 cm 3 molecule -1 s -1 at 298 K. These results are discussed and compared with other literature values.

  19. Direct Determination of the Rate Coefficient for the Reaction of OH Radicals with Monoethanol Amine (MEA) from 296 to 510 K.

    PubMed

    Onel, L; Blitz, M A; Seakins, P W

    2012-04-05

    Monoethanol amine (H2NCH2CH2OH, MEA) has been proposed for large-scale use in carbon capture and storage. We present the first absolute, temperature-dependent determination of the rate coefficient for the reaction of OH with MEA using laser flash photolysis for OH generation, monitoring OH removal by laser-induced fluorescence. The room-temperature rate coefficient is determined to be (7.61 ± 0.76) × 10(-11) cm(3) molecule(-1) s(-1), and the rate coefficient decreases by about 40% by 510 K. The temperature dependence of the rate coefficient is given by k1= (7.73 ± 0.24) × 10(-11)(T/295)(-(0.79±0.11)) cm(3) molecule(-1) s(-1). The high rate coefficient shows that gas-phase processing in the atmosphere will be competitive with uptake onto aerosols.

  20. Direct evidence for a substantive reaction between the Criegee intermediate, CH2OO, and the water vapour dimer.

    PubMed

    Lewis, Tom R; Blitz, Mark A; Heard, Dwayne E; Seakins, Paul W

    2015-02-21

    The C1 Criegee intermediate, CH2OO, reaction with water vapour has been studied. The removal rate constant shows a quadratic dependence on [H2O], implying reaction with the water dimer, (H2O)2. The rate constant, kCH2OO+(H2O)2 = (4.0 ± 1.2) × 10(-12) cm(3) molecule(-1) s(-1), is such that this is the major atmospheric sink for CH2OO.

  1. On rates and mechanisms of OH and O3 reactions with isoprene-derived hydroxy nitrates.

    PubMed

    Lee, Lance; Teng, Alex P; Wennberg, Paul O; Crounse, John D; Cohen, Ronald C

    2014-03-06

    Eight distinct hydroxy nitrates are stable products of the first step in the atmospheric oxidation of isoprene by OH. The subsequent chemical fate of these molecules affects global and regional production of ozone and aerosol as well as the location of nitrogen deposition. We synthesized and purified 3 of the 8 isoprene hydroxy nitrate isomers: (E/Z)-2-methyl-4-nitrooxybut-2-ene-1-ol and 3-methyl-2-nitrooxybut-3-ene-1-ol. Oxidation of these molecules by OH and ozone was studied using both chemical ionization mass spectrometry and thermo-dissociation laser induced fluorescence. The OH reaction rate constants at 300 K measured relative to propene at 745 Torr are (1.1 ± 0.2) × 10(-10) cm(3) molecule(-1) s(-1) for both the E and Z isomers and (4.2 ± 0.7) × 10(-11) cm(3) molecule(-1) s(-1) for the third isomer. The ozone reaction rate constants for (E/Z)-2-methyl-4-nitrooxybut-2-ene-1-ol are (2.7 ± 0.5) × 10(-17) and (2.9 ± 0.5) × 10(-17) cm(3) molecule(-1) s(-1), respectively. 3-Methyl-2-nitrooxybut-3-ene-1-ol reacts with ozone very slowly, within the range of (2.5-5) × 10(-19) cm(3) molecule(-1) s(-1). Reaction pathways, product yields, and implications for atmospheric chemistry are discussed. A condensed mechanism suitable for use in atmospheric chemistry models is presented.

  2. Kinetic study of IO radical with RO2 (R = CH(3), C2H5, and CF3) using cavity ring-down spectroscopy.

    PubMed

    Enami, Shinichi; Yamanaka, Takashi; Hashimoto, Satoshi; Kawasaki, Masahiro; Nakano, Yukio; Ishiwata, Takashi

    2006-08-17

    The reactions of iodine monoxide radical, IO, with alkyl peroxide radicals, RO(2) (R = CH(3), C(2)H(5), and CF(3)), have been studied using cavity ring-down spectroscopy. The rate constant of the reaction of IO with CH(3)O(2) was determined to be (7.0 +/- 3.0) x 10(-11) cm(3) molecule(-1) s(-1) at 298 K and 100 Torr of N(2) diluent. The quoted uncertainty is two standard deviations. No significant pressure dependence of the rate constant was observed at 30-130 Torr total pressure of N(2) diluent. The temperature dependence of the rate constants was also studied at 213-298 K. The upper limit of the branching ratio of OIO radical formation from IO + CH(3)O(2) was estimated to be <0.1. The reaction rate constants of IO + C(2)H(5)O(2) and IO + CF(3)O(2) were determined to be (14 +/- 6) x 10(-11) and (6.3 +/- 2.7) x 10(-11) cm(3) molecule(-1) s(-1) at 298 K, 100 Torr of N(2) diluent, respectively. The upper limit of the reaction rate constant of IO with CH(3)I was <4 x 10(-14) cm(3) molecule(-1) s(-1).

  3. A kinetic study of the CH2OO Criegee intermediate self-reaction, reaction with SO2 and unimolecular reaction using cavity ring-down spectroscopy.

    PubMed

    Chhantyal-Pun, Rabi; Davey, Anthony; Shallcross, Dudley E; Percival, Carl J; Orr-Ewing, Andrew J

    2015-02-07

    Criegee intermediates are important species formed during the ozonolysis of alkenes. Reaction of stabilized Criegee intermediates with various species like SO2 and NO2 may contribute significantly to tropospheric chemistry. In the laboratory, self-reaction can be an important loss pathway for Criegee intermediates and thus needs to be characterized to obtain accurate bimolecular reaction rate coefficients. Cavity ring-down spectroscopy was used to perform kinetic measurements for various reactions of CH2OO at 293 K and under low pressure (7 to 30 Torr) conditions. For the reaction CH2OO + CH2OO (8), a rate coefficient k8 = (7.35 ± 0.63) × 10(-11) cm(3) molecule(-1) s(-1) was derived from the measured CH2OO decay rates, using an absorption cross section value reported previously. A rate coefficient of k4 = (3.80 ± 0.04) × 10(-11) cm(3) molecule(-1) s(-1) was obtained for the CH2OO + SO2 (4) reaction. An upper limit for the unimolecular CH2OO loss rate coefficient of 11.6 ± 8.0 s(-1) was deduced from studies of reaction (4). SO2 catalysed CH2OO isomerization or intersystem crossing is proposed to occur with a rate coefficient of (3.53 ± 0.32) × 10(-11) cm(3) molecule(-1) s(-1).

  4. Heavy water reactions with alkaline-earth metal dications in the gas phase

    NASA Astrophysics Data System (ADS)

    Feil, Stefan; Koyanagi, Greg K.; Bohme, Diethard K.

    2009-02-01

    Room temperature rate coefficients and product distributions are reported for the reactions initiated in D2O with dications of the alkaline-earth metals Mg, Ca, Sr and Ba. The measurements were performed with a selected-ion flow tube (SIFT) tandem mass spectrometer and electrospray ionization (ESI). Mg2+ reacts with water by a fast electron transfer leading to charge separation with a rate coefficient of 1.4 × 10-9 cm3 molecule-1 s-1. Ca2+ reacts with D2O in a first step to form the adduct Ca2+(D2O), with an effective bimolecular rate coefficient of 2.3 × 10-11 cm3 molecule-1 s-1, which then undergoes rapid charge separation by deuteron transfer to form CaOD+ and D3O+ in a second step with k = 7.9 × 10-10 cm3 molecule-1 s-1. The CaOD+ ion reacts further by clustering up to five more D2O molecules. Sr2+ clusters up to eight D2O molecules and Ba2+ up to seven D2O molecules, with the first addition of D2O being rate determining in each case and the last addition being distinctly slower, as might be expected from a transition in the occupation of the added water molecules from an inner to an outer hydration shell.

  5. OH initiated heterogeneous degradation of organophosphorus compounds

    NASA Astrophysics Data System (ADS)

    Liggio, J.; Liu, Y.; Harner, T.; Jantunen, L.; Shoeib, M.; Li, S.

    2013-12-01

    Organophosphorus compounds (OPs) have been extensively used worldwide as flame retardants, plasticizers, antifoaming agents, and additives because of their favorable physicochemical characteristics. The global consumption of OPs is likely to greatly increase due to the phasing out of bromine-containing flame retardants (BFRs) with OPs identified as possible substitutes. In most applications, OPs easily leach out of the material into the environment via volatilization, abrasion, and dissolution and have been observed widely in atmospheric particles even in polar regions. However, little is known about their atmospheric fate. The Canadian Chemicals Management Plan (CMP) has targeted OP FRs for risk assessment, including assessing stability and atmospheric transport potential of OP FRs and other priority chemicals that are associated primarily with particles. In the current study, OH initiated heterogeneous reaction kinetics of tris(1,3-dichloro-2-propyl) phosphate (TDCPP), tris-2-ethylhexyl-phosphate (TEHP), tris-2-butoxyethyl-phosphate (TBEP), and tri-phenyl phosphate (TPhP) coated on (NH4)2SO4 were investigated using a photo-chemical flow tube which was coupled to an Aerosol Mass Spectrometer (AMS) and Proton Transfer Reaction Mass Spectrometer (PTR-MS). second-order rate constants (k2) for the heterogeneous loss of TPhP, TEHP and TDCPP were (2.07×0.19)×10-12, (2.69×0.63)×10-12 and (9.22×0.92)×10-13 cm3 molecule-1 s-1, respectively, from which approximate atmospheric lifetimes were estimated to be 5.6 (5.2-6.0), 4.3 (3.5-5.6), and 12.6 (11.4-14.0) days. These results represent the first reported estimates of heterogeneous rate constants for these species, and suggest that particle bound OPEs will be highly persistent in the atmosphere, supporting the assumption that OPEs can undergo medium or long-range transport, as proposed on the basis of field measurements.

  6. Sterilization of Surfaces with a Handheld Atmospheric Pressure Plasma

    NASA Astrophysics Data System (ADS)

    Hicks, Robert; Habib, Sara; Chan, Wai; Gonzalez, Eleazar; Tijerina, A.; Sloan, Mark

    2009-10-01

    Low temperature, atmospheric pressure plasmas have shown great promise for decontaminating the surfaces of materials and equipment. In this study, an atmospheric pressure, oxygen and argon plasma was investigated for the destruction of viruses, bacteria, and spores. The plasma was operated at an argon flow rate of 30 L/min, an oxygen flow rate of 20 mL/min, a power density of 101.0 W/cm^3 (beam area = 5.1 cm^2), and at a distance from the surface of 7.1 mm. An average 6log10 reduction of viable spores was obtained after only 45 seconds of exposure to the reactive gas. By contrast, it takes more than 35 minutes at 121^oC to sterilize anthrax in an autoclave. The plasma properties were investigated by numerical modeling and chemical titration with nitric oxide. The numerical model included a detailed reaction mechanism for the discharge as well as for the afterglow. It was predicted that at a delivered power density of 29.3 W/cm^3, 30 L/min argon, and 0.01 volume% O2, the plasma generated 1.9 x 10^14 cm-3 O atoms, 1.6 x 10^12 cm-3 ozone, 9.3 x 10^13 cm-3 O2(^1δg), and 2.9 x 10^12 cm-3 O2(^1σ^+g) at 1 cm downstream of the source. The O atom density measured by chemical titration with NO was 6.0 x 10^14 cm-3 at the same conditions. It is believe that the oxygen atoms and the O2(^1δg) metastables were responsible for killing the anthrax and other microorganisms.

  7. Laboratory study on OH-initiated degradation kinetics of dehydroabietic acid.

    PubMed

    Lai, Chengyue; Liu, Yongchun; Ma, Jinzhu; Ma, Qingxin; He, Hong

    2015-04-28

    Dehydroabietic acid (DHAA) is a specific organic tracer for the pyrolysis of conifer resin. To understand its atmospheric stability, the degradation behavior of particulate DHAA in the presence of hydroxyl radicals (OH) was investigated under different environmental conditions using a stainless steel reactor with volume of 30 cm(3), in the dark. At 25 °C and 40% relative humidity (RH), the second-order rate constant (k2) of pure DHAA with OH was measured to be 5.72 ± 0.87 × 10(-12) cm(3) molecule(-1) s(-1). The influence of temperature, RH and mixing state on the degradation kinetics of DHAA were also investigated. At 40% RH, k2 of pure DHAA increases with increasing temperature and follows the Arrhenius equation k2 = (8.9 ± 1.9) × 10(-10) exp[-(1508.2 ± 64.2)/T], while RH does not have significant impact on k2 at 25 °C. At 25 °C and 40% RH, compared with pure DHAA, the corresponding k2 for DHAA mixed with (NH4)2SO4 decreased to 4.58 ± 0.95 × 10(-12) cm(3) molecule(-1) s(-1), while the value was 3.30 ± 0.79 × 10(-12) cm(3) molecule(-1) s(-1) when mixed with soot. The atmospheric lifetime of DHAA varied from 2.3 ± 0.2 to 4.4 ± 0.8 days under different environmental conditions. This study indicates that degradation of DHAA by OH radicals is appreciable, and a significant error in source apportionment should be introduced if the contribution of degradation to DHAA concentration is not considered during air mass aging.

  8. Atmospheric chemistry of hydrazoic acid (HN3): UV absorption spectrum, HO reaction rate, and reactions of the N3 radical.

    PubMed

    Orlando, John J; Tyndall, Geoffrey S; Betterton, Eric A; Lowry, Joe; Stegall, Steve T

    2005-03-15

    Processes related to the tropospheric lifetime and fate of hydrazoic acid, HN3, have been studied. The ultraviolet absorption spectrum of HN3 is shown to possess a maximum near 262 nm with a tail extending to at least 360 nm. The photolysis quantum yield for HN3 is shown to be approximately 1 at 351 nm. Using the measured spectrum and assuming unity quantum yield throughout the actinic region, a diurnally averaged photolysis lifetime near the earth's surface of 2-3 days is estimated. Using a relative rate method, the rate coefficient for reaction of HO with HN3 was found to be (3.9 +/-0.8) x 10(-12) cm3 molecule(-1) s(-1), substantially larger than the only previous measurement. The atmospheric HN3 lifetime with respect to HO oxidation is thus about 2-3 days, assuming a diurnally averaged [HO] of 10(6) molecule cm(-3). Reactions of N3, the product of the reaction of HO with HN3, were studied in an environmental chamber using an FTIR spectrometer for end-product analysis. The N3 radical reacts efficiently with NO, producing N2O with 100% yield. Reaction of N3 with NO2 appears to generate both NO and N2O, although the rate coefficient for this reaction is slower than that for reaction with NO. No evidence for reaction of N3 with CO was observed, in contrast to previous literature data. Reaction of N3 with O2 was found to be extremely slow, k < 6 x 10(-20) cm3 molecule(-1) s(-1), although this upper limit does not necessarily rule out its occurrence in the atmosphere. Finally, the rate coefficient for reaction of Cl with HN3 was measured using a relative rate method, k = (1.0+/-0.2) x 10(-12) cm3 molecule(-1) s(-1).

  9. A Penetration Mechanics Database

    DTIC Science & Technology

    1992-01-31

    Metal Projectiles with a Velocity Higher than 2000 m/s," Science et Techniques de r’Armement, 56, pp . 1-155. Rosenberg, Z. and M. J. Forrestal (1988...3140 Yaw (deg) 13 0 13 2 15 4 4 RESIULTS P (mm) 3.0 1.0 6.6 4.1 6.1 8.1 12.9 d (min) 5.60 7.60 5.6 6.6 8.1 15.0 Vol (cm 3) .05 .27 . 07 .2 .31 1.6...3.2 5.3 10.2 13.1 14.7 d (mm) 3.3 5.8 8.4 5.8 7.9 11.9 16.3 Vol (cm 3) .02 .10 .13 .40 . 78 2.60 SCALING P/AXL .054 .233 .573 .551 1.061 1.363 1.529

  10. Properties of Laser Produced TMAE Plasma Admixed with Air Constituents, Nitrogen and Noble Gases

    NASA Astrophysics Data System (ADS)

    Ding, Guowen; Scharer, John; Kelly, Kurt

    1999-10-01

    A high initial density (> 10^13 cm-3) and a large volume (hundreds of cm^3) plasma is created by a 193 nm laser ionization of an organic molecule, tetrakis(dimethyl-amino)ethylene(TMAE). The properties of this plasma mixed with nitrogen and noble gases are studied. Fast probe measurements which include a detailed considerations of probe structure, probe surface cleaning, shielding, probe perturbation, frequency response, temporal and spatial resolutions, dummy probe corrections and noise analysis will be described. Electron densities obtained by this method are independent on the ion species mixture. A plasma emission diagnostic is used to estimate plasma densities for the higher admixture pressures. Electron density and temperature vs. time for various TMAE, nitrogen and noble gas pressures and laser power will be presented. The role of super-excited and metastable states in the decay process will also be discussed.

  11. Supernova matter at subnuclear densities as a resonant Fermi gas: enhancement of neutrino rates.

    PubMed

    Bartl, A; Pethick, C J; Schwenk, A

    2014-08-22

    At low energies nucleon-nucleon interactions are resonant and therefore supernova matter at subnuclear densities has many similarities to atomic gases with interactions dominated by a Feshbach resonance. We calculate the rates of neutrino processes involving nucleon-nucleon collisions and show that these are enhanced in mixtures of neutrons and protons at subnuclear densities due to the large scattering lengths. As a result, the rate for neutrino pair bremsstrahlung and absorption is significantly larger below 10(13) g cm(-3) compared to rates used in supernova simulations.

  12. Picosecond imaging of low-density plasmas by electron deflectometry.

    PubMed

    Centurion, M; Reckenthaeler, P; Krausz, F; Fill, E E

    2009-02-15

    We have imaged optical-field ionized plasmas with electron densities as low as 10(13) cm(-3) on a picosecond timescale using ultrashort electron pulses. Electric fields generated by the separation of charges are imprinted on a 20 keV probe electron pulse and reveal a cloud of electrons expanding away from a positively charged plasma core. Our method allows for a direct measurement of the electron energy required to escape the plasma and the total charge. Simulations reproduce the main features of the experiment and allow determination of the energy of the electrons.

  13. Reduction of atherosclerosis in cholesterol-fed rabbits and decrease of expressions of intracellular adhesion molecule-1 and vascular endothelial growth factor in foam cells by a water-soluble fraction of Polygonum multiflorum.

    PubMed

    Yang, Peng-Yuan; Almofti, Mohamad Radwan; Lu, Ling; Kang, Hui; Zhang, Jing; Li, Tie-Jun; Rui, Yao-Cheng; Sun, Lian-Na; Chen, Wan-Sheng

    2005-11-01

    Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb., one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.

  14. The small molecule '1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate' and its derivatives regulate global protein synthesis by inactivating eukaryotic translation initiation factor 2-alpha.

    PubMed

    Hong, Mi-Na; Nam, Ky-Youb; Kim, Kyung Kon; Kim, So-Young; Kim, InKi

    2016-05-01

    By environmental stresses, cells can initiate a signaling pathway in which eukaryotic translation initiation factor 2-alpha (eIF2-α) is involved to regulate the response. Phosphorylation of eIF2-α results in the reduction of overall protein neogenesis, which allows cells to conserve resources and to reprogram energy usage for effective stress control. To investigate the role of eIF2-α in cell stress responses, we conducted a viability-based compound screen under endoplasmic reticulum (ER) stress condition, and identified 1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate (AMC-01) and its derivatives as eIF2-α-inactivating chemical. Molecular characterization of this signaling pathway revealed that AMC-01 induced inactivation of eIF2-α by phosphorylating serine residue 51 in a dose- and time-dependent manner, while the negative control compounds did not affect eIF2-α phosphorylation. In contrast with ER stress induction by thapsigargin, phosphorylation of eIF2-α persisted for the duration of incubation with AMC-01. By pathway analysis, AMC-01 clearly induced the activation of protein kinase RNA-activated (PKR) kinase and nuclear factor-κB (NF-κB), whereas it did not modulate the activity of PERK or heme-regulated inhibitor (HRI). Finally, we could detect a lower protein translation rate in cells incubated with AMC-01, establishing AMC-01 as a potent chemical probe that can regulate eIF2-α activity. We suggest from these data that AMC-01 and its derivative compounds can be used as chemical probes in future studies of the role of eIF2-α in protein synthesis-related cell physiology.

  15. Resistance to cerebral malaria in tumor necrosis factor-alpha/beta-deficient mice is associated with a reduction of intercellular adhesion molecule-1 up-regulation and T helper type 1 response.

    PubMed Central

    Rudin, W.; Eugster, H. P.; Bordmann, G.; Bonato, J.; Müller, M.; Yamage, M.; Ryffel, B.

    1997-01-01

    Tumor necrosis factor (TNF) induced by Plasmodium berghei ANKA (PbA) infection was suggested to play an important role in the development of cerebral malaria (CM). We asked whether TNF-alpha/beta double-deficient mice, which have a complete disruption of the TNF-signaling pathways, are protected from CM and what might be the possible mechanisms of protection. PbA infection induces fatal CM in wild-type mice, which die within 5 to 8 days with severe neurological signs. In contrast, TNF-alpha/beta-deficient mice are completely resistant to PbA-induced CM. As PbA-induced up-regulation of endothelial intercellular adhesion molecule (ICAM)-1 expression as well as the systemic release of nitric oxide is found only in wild-type mice, TNF is apparently central for the recruitment of mononuclear cells and microvascular damage. Mononuclear cell adhesion to the endothelium, vascular leak and, perivascular hemorrhage are found only in the brain of wild-type mice. By contrast, the development of parasitemia and anemia is independent of TNF. Resistance to CM in TNF-alpha/beta-deficient mice is associated with reduced interferon-gamma and interleukin-12 expression in the brain, in the absence of increased T helper type 2 cytokines. In conclusion, TNF apparently is required for PbA-induced endothelial ICAM-1 up-regulation and subsequent microvascular pathology resulting in fatal CM. In the absence of TNF, ICAM-1 and nitric oxide up-regulation are reduced, and PbA infection fails to cause fatal CM. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:9006341

  16. Circulating concentrations of monocyte chemoattranctant protein-1, plasminogen activator inhibitor-1, & soluble leukocyte adhesion molecule-1 in overweight/obese men/women consuming fructose-or glucose-sweetened beverages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Results from animal studies suggest that consumption of large amounts of fructose can promote inflammation and impair fibrinolysis. Data describing the effects of fructose consumption on levels of pro-inflammatory and pro-thrombotic markers in humans are unavailable. The objective of this study was ...

  17. Spin-inversion and spin-selection in the reactions FeO(+) + H2 and Fe(+) + N2O.

    PubMed

    Ard, Shaun G; Johnson, Ryan S; Melko, Joshua J; Martinez, Oscar; Shuman, Nicholas S; Ushakov, Vladimir G; Guo, Hua; Troe, Jürgen; Viggiano, Albert A

    2015-08-14

    The reactions of FeO(+) with H2 and of Fe(+) with N2O were studied with respect to the production and reactivity of electronically excited (4)Fe(+) cations. The reaction of electronic ground state (6)FeO(+) with H2 was found to predominantly produce electronically excited (4)Fe(+) as opposed to electronic ground state (6)Fe(+) corresponding to a spin-allowed reaction. (4)Fe(+) was observed to react with N2O with a rate constant of 2.3 (+0.3/-0.8) × 10(-11) cm(3) molecule(-1) s(-1), smaller than the ground state (6)Fe(+) rate constant of 3.2 (±0.5) × 10(-11) cm(3) molecule(-1) s(-1) (at room temperature). While the overall reaction of (6)FeO(+) with H2 within the Two-State-Reactivity concept is governed by efficient sextet-quartet spin-inversion in the initial reaction complex, the observation of predominant (4)Fe(+) production in the reaction is attributed to a much less efficient quartet-sextet back-inversion in the final reaction complex. Average spin-inversion probabilities are estimated by statistical modeling of spin-inversion processes and related to the properties of spin-orbit coupling along the reaction coordinate. The reaction of FeO(+) with H2 served as a source for (4)Fe(+), subsequently reacting with N2O. The measured rate constant has allowed for a more detailed understanding of the ground state (6)Fe(+) reaction with N2O, leading to a significantly improved statistical modeling of the previously measured temperature dependence of the reaction. In particular, evidence for the participation of electronically excited states of the reaction complex was found. Deexcitation of (4)Fe(+) by He was found to be slow, with a rate constant <3 × 10(-14) cm(3) molecule(-1) s(-1).

  18. Influence of temperature on the chemical removal of 3-methylbutanal, trans-2-methyl-2-butenal, and 3-methyl-2-butenal by OH radicals in the troposphere

    NASA Astrophysics Data System (ADS)

    Jiménez, Elena; Lanza, Beatriz; Antiñolo, María; Albaladejo, José

    Absolute rate coefficients for the gas-phase reactions of OH radical with 3-methylbutanal ( k1), trans-2-methyl-2-butenal ( k2), and 3-methyl-2-butenal ( k3) have been obtained with the pulsed laser photolysis/laser-induced fluorescence technique. Gas-phase concentration of aldehydes was measured by UV absorption spectroscopy at 185 nm. Experiments were performed over the temperature range of 263-353 K at total pressures of helium between 46.2 and 100 Torr. No pressure dependence of all ki ( i = 1-3) was observed at all temperatures. In contrast, a negative temperature dependence of ki ( i.e., ki increases when temperature decreases) was observed in that T range. The resulting Arrhenius expressions (±2 σ) are: k1( T) = (5.8 ± 1.7)×10 -12 exp{(499 ± 94)/ T} cm 3 molecule -1 s -1, k2( T)=(6.9 ± 0.9)×10 -12 exp{(526 ± 42)/ T} cm 3 molecule -1 s -1, k3( T)=(5.6 ± 1.2)×10 -12 exp{(666 ± 54)/ T} cm 3 molecule -1 s -1. The tropospheric lifetimes derived from the above OH-reactivity trend are estimated to be higher for 3-methylbutanal than those for the unsaturated aldehydes. A comparison of the tropospheric removal of these aldehydes by OH radicals with other homogeneous degradation routes leads to the conclusion that this reaction can be the main homogeneous removal pathway. However, photolysis of these aldehydes in the actinic region ( λ > 290 nm) could play an important role along the troposphere, particularly for 3-methyl-2-butenal. This process could compete with the OH reaction for 3-methylbutanal or be negligible for trans-2-methyl-2-butenal in the troposphere.

  19. Atmospheric degradation and global warming potentials of three perfluoroalkenes

    NASA Astrophysics Data System (ADS)

    Acerboni, G.; Beukes, J. A.; Jensen, N. R.; Hjorth, J.; Myhre, G.; Nielsen, C. J.; Sundet, J. K.

    The vapour phase reactions of perfluoropropene, CF 3CFCF 2, and perfluorobuta-1,3-diene, CF 2CFCFCF 2, with OH, NO 3 and O 3 were studied at 298±4 K and 740±5 Torr using long-path FT-IR detection. The reactions with ozone are very slow, kCF 3CFCF 2+O 3=(6.2±1.5)×10 -22 and kCF 2CFCFCF 2+O 3=(6.5±0.2)×10 -21 cm 3 molecules -1 s -1, and upper limits of 3×10 -15 cm 3 molecules -1 s -1 are reported for the NO 3 reaction rate coefficients. The OH reaction rate coefficients were determined as kCF 3CFCF 2+OH =(2.6±0.7)×10 -12 and kCF 2CFCFCF 2+OH =(1.1±0.3)×10 -11 cm 3 molecules -1 s -1; perfluoropropene gave a nearly quantitative yield of CF 3CFO and CF 2O as organic products, while perfluorobuta-1,3-diene gave from 130% to 170% of CF 2O. A chemistry transport model was applied to calculate the atmospheric distributions and lifetimes of the perfluoroalkenes; the global and yearly averaged lifetimes were calculated as 1.9 day for C 2F 4 and C 4F 6 and 6 days for C 3F 6. Quantitative infrared cross-sections of perfluoroethene, perfluoropropene, and perfluorobuta-1,3-diene have been obtained at 298 K in the region 100-2600 cm -1. Radiative forcing calculations have been performed for these gases assuming either constant vertical profiles or the distribution derived from the chemistry transport model. The results show that the Global Warming Potentials are totally negligible for these compounds.

  20. Heterogeneous reactions of ozone with pyrene, 1-hydroxypyrene and 1-nitropyrene adsorbed on particles

    NASA Astrophysics Data System (ADS)

    Miet, K.; Le Menach, K.; Flaud, P. M.; Budzinski, H.; Villenave, E.

    This work deals with the kinetic study of the reactions of ozone with pyrene, 1-hydroxypyrene and 1-nitropyrene, adsorbed on model particles. Experiments were performed at room temperature and atmospheric pressure, using a quasi-static flow reactor in the absence of light. Compounds were extracted from particles using pressurized fluid extraction (PFE) and concentration measurements were performed using gas chromatography/mass spectrometry (GC/MS). The pseudo-first order rate constants were obtained from the fit of the experimental decay of particulate polycyclic compound concentrations versus reaction time. Experiments were performed at three different O 3 concentrations from which second order rate constants were calculated. The following rate constant values were obtained at 293 K: k(O 3 + Pyrene) = (3.2 ± 0.7) × 10 -16 cm 3 molecule -1 s -1; k(O 3 + 1OHP) = (7.7 ± 1.4) ×10 -16 cm 3 molecule -1 s -1; and k(O 3 + 1NP) = (2.2 ± 0.5) × 10 -17 cm 3 molecule -1 s -1, for pyrene, 1-hydroxypyrene and 1-nitropyrene adsorbed on silica particles. The variation in the rate constants demonstrates the strong influence of the substituent (OH or NO 2) on the heterogeneous reactivity of pyrene. The pyrene particulate concentration was also varied in order to check how this parameter may influence the experiments. Finally, oxidation products were investigated for all reactions and some were detected and identified for the first time for ozone heterogeneous reaction with pyrene adsorbed on particles.

  1. Pressure and temperature dependence of the reaction of vinyl radical with alkenes III: measured rates and predicted product distributions for vinyl + butene.

    PubMed

    Goldsmith, C Franklin; Ismail, Huzeifa; Green, William H

    2009-11-26

    This work reports experimental and theoretical first-order rate constants for the reaction of vinyl radical with C(4)H(8) alkenes: 1-butene, 2-butene, and isobutene. The experiments are performed over a temperature range of 300 to 700 K at 100 Torr. Vinyl radicals (H(2)C horizontal lineCH) were generated by laser photolysis of vinyl iodide (C(2)H(3)I) at 266 nm, and time-resolved absorption spectroscopy was used to probe vinyl radicals at 423.2 and 475 nm. Weighted Arrhenius fits to the experimental rate coefficients for 1-butene (k(1)), 2-butene (k(2)), and isobutene (k(3)) yield k(1) = (1.3 +/- 0.3) x 10(-12) cm(3) molecules(-1) s(-1) exp[-(2200 +/- 120) K/T]; k(2) = (1.7 +/- 0.3) x 10(-12) cm(3) molecules(-1) s(-1) exp[-(2610 +/- 120) K/T]; and k(3) = (1.0 +/- 0.1) x 10(-12) cm(3) molecules(-1) s(-1) exp[-(2130 +/- 50) K/T], respectively. C(6)H(11) potential energy surfaces (PESs) for each system were calculated using the G3 method. RRKM/ME simulations were performed for each system to predict pressure-dependent rate coefficients and branching fractions for the major channels. A generic rate rule for vinyl addition to various alkenes is recommended; a similar rate rule for the abstraction of H atoms by vinyl from alkenes is also provided. Some of the vinyl addition reactions exhibit anomalous Evans-Polanyi plots similar to those reported for previous methyl addition reactions.

  2. An experimental kinetic study and products research of the reactions of O3 with a series of unsaturated alcohols

    NASA Astrophysics Data System (ADS)

    Chen, Yi; Wang, Jing; Zhao, Sanping; Tong, Shengrui; Ge, Maofa

    2016-11-01

    The gas-phase reactions of unsaturated alcohols with O3 were investigated in FEP Teflon film chamber at 298 K and 760 torr of atmosphere pressure. The rate constants of the reactions of C6-C8 alkenols with O3 were determined using both the absolute and the relative rate method, and the measured values were (5.96 ± 0.35) × 10-17 cm3 molecule-1 s-1 for (Z)-3-hexen-1-ol, (5.12 ± 0.30) × 10-17 cm3 molecule-1 s-1 for (Z)-3-hepten-1-ol, and (5.66 ± 0.52) × 10-17 cm3 molecule-1 s-1 for (Z)-3-octen-1-ol, respectively. The gas-phase products of these reactions mentioned above were detected using proton-transfer-reaction mass spectrum (PTR-MS). HOCH2CH2CHO, CH2CH2CHO, HCHO and CH3CHO were identified as the main gas products for (Z)-3-hexen-1-ol. HOCH2CH2CHO and CH3(CH2)2CHO dominated the gaseous products for (Z)-3-hepten-1-ol. And for (Z)-3-octen-1-ol, CH3(CH2)3CHO, CH3(CH2)2CHO and HOCH2CH2CHO were the main gaseous products. The SOA yields were monitored at the same time, which were 0.184 ± 0.013, 0.213 ± 0.017, 0.232 ± 0.021 for (Z)-3-hexen-1-ol, (Z)-3-hepten-1-ol and (Z)-3-octen-1-ol, respectively. The possible reaction mechanisms were proposed and discussed. The kinetic data presented here has been used to estimate their atmosphere lifetimes and the reaction reactivity. The atmosphere implication of these reactions has also been discussed.

  3. Kinetics and Mechanism of the Gas-Phase Reaction of Selected Carbonyls with Cl Atoms between 250 and 340 K

    NASA Astrophysics Data System (ADS)

    Hasson, A. S.; Algrim, L.; Abdelhamid, A.; Tyndall, G. S.; Orlando, J. J.

    2013-12-01

    Carbonyls are important products from the gas phase degradation of most volatile organic compounds. Their atmospheric reactions therefore have a significant impact on atmospheric composition, particularly in aged air masses. While the reactions of short-chain linear carbonyls are well understood, the chemistry of larger (> C6) and branched carbonyl is more uncertain. To provide insight into these reactions, the reactions of three carbonyls (methyl isopropyl ketone, MIK; di-isopropyl ketone, DIK; and diethyl ketone, DEK) with chlorine atoms were investigated between 250 and 340 K and 1 atm in the presence and absence of NOx and an HO2 source (methanol). Experiments were performed in a photochemical reactor using a combination of long-path Fourier transform infra-red spectroscopy, proton transfer reaction mass spectrometry and gas chromatography with flame ionization detection. The kinetics were studied using the relative rate technique with butanone and isopropanol as the reference compounds. The Arrhenius expression for the three rate coefficients was determined to be k(DEK+Cl) = 3.87 x 10-11e(2 × 7 kJ/mol)/RT cm3 molecules-1 s-1 , k(MIPK+Cl) = 7.20 x 10-11e(0.2× 8 kJ/mol)/RT cm3 molecules-1 s-1 , and k(DIPK+Cl) = 3.33 x 10-10e(-3× 8 kJ/mol)/RT cm3 molecules-1 s-1 . Measured reaction products accounted for 38-72 % of the reacted carbon and were consistent with strong deactivation of the carbon atom adjacent to the carbonyl group with respect to H-atom abstraction by Cl atoms. The product distributions also provide insight into radical recycling from the organic peroxy + HO2 reaction, and the relative rates of isomerization, fragmentation and reaction with O2 for carbonyl-containing alkoxy radicals. Implications of these results will be discussed.

  4. Rate coefficients for the OH + CFH2CH2OH reaction between 238 and 355 K.

    PubMed

    Rajakumar, B; Burkholder, James B; Portmann, R W; Ravishankara, A R

    2005-06-21

    The rate coefficient for the reaction OH + CFH2CH2OH --> products (k1) between 238 and 355 K was measured using the pulsed laser photolysis-laser induced fluorescence (PLP-LIF) technique to be (5.15 +/- 0.88)x 10(-12) exp[-(330 +/- 45)/T] cm3 molecule(-1) s(-1); k1(298 K)= 1.70 x 10(-12) cm3 molecule(-1) s(-1). The quoted uncertainties are 2sigma(95% confidence level) and include estimated systematic errors. The present results are discussed in relation to the measured rate coefficients for the reaction of OH with other fluorinated alcohols and those calculated using recently reported structure additivity relationships for fluorinated compounds (K. Tokuhashi, H. Nagai, A. Takahashi, M. Kaise, S. Kondo, A. Sekiya, M. Takahashi, Y. Gotoh and A. Suga, J. Phys. Chem. A, 1999, 103, 2664-2672, ). Infrared absorption cross sections for CFH2CH2OH are reported and they are used to calculate the global warming potentials (GWP) for CFH2CH2OH of approximately 8, approximately 2, and approximately 1, respectively, for the 20, 100 and 500 year horizons. A brief discussion of the atmospheric degradation of CFH2CH2OH is provided. It is concluded that CFH2CH2OH is an acceptable substitute for CFCs in terms of its impact on Earth's climate and the composition of the atmosphere. The room temperature rate coefficient for the reaction OH + CFH2CH2OH --> products (k10) was measured to be 3.26 x 10(-12) cm3 molecule(-1) s(-1), in good agreement with recent measurements from this laboratory.

  5. Kinetics of the reaction of Cl atoms with CHCl 3 over the temperature range 253-313 K

    NASA Astrophysics Data System (ADS)

    Nilsson, Elna J. K.; Hoff, Janus; Nielsen, Ole John; Johnson, Matthew S.

    2010-07-01

    The reaction CHCl 3 + Cl → CCl 3 + HCl was studied in the atmospherically relevant temperature range from 253 to 313 K and in 930 mbar of N 2 diluent using the relative rate method. A temperature dependent reaction rate constant, valid in the temperature range 220-330 K, was determined by a fit to the result of the present study and that of Orlando (1999); k = (3.77 ± 0.32) × 10 -12 exp((-1011 ± 24)/T) cm 3 molecule -1 s -1.

  6. Kinetics of Iodine Monofluoride Excitation by Energetic Nitrogen.

    DTIC Science & Technology

    1985-10-01

    fluorescence for measuring IF number densities. The energy transfer reaction between IF(X) and N2 (A) was extremely rapid (k = 2.0 x 10-1° cm3 molecule-1S-l... measured . Active nitrogen, created in microwave discharges in Ar/N2 mixtures, also excited IF(B) strongly when ground-state IF mixed with it. A 2000 K... measurements at 580 nm in the presence of known quantities of 0 and NO calibrated our system for absolute photon emission-rate measurements . Relative

  7. Crystal structure of N-[(8E)-12-methyl-14-phenyl-10,13,14,16-tetra-aza-tetra-cyclo-[7.7.0.0(2,7).0(11,15)]hexa-deca-1(16),2,4,6,9,11(15),12-heptaen-8-yl-idene]hydroxyl-amine 1,4-dioxane hemisolvate.

    PubMed

    Mohamed, Shaaban K; Mague, Joel T; Akkurt, Mehmet; El-Emary, Talaat I; Albayati, Mustafa R

    2015-02-01

    In the title solvate, C19H13N5O·0.5C4H8O2, the main mol-ecule is almost planar (r.m.s. deviation for the non-H atoms = 0.066 Å). The hydroxyl-amine group is disordered over two orientations in a 0.761 (4):0.239 (4) ratio. The complete dioxane solvent mol-ecule is generated by a crystallographic inversion centre. In the crystal, both disorder components of the hydroxyl-amine group form O-H⋯N hydrogen bonds to the same N-atom acceptor, thereby generating [010] chains. The chains encompass [010] channels occupied by the solvent mol-ecules. Aromatic π-π stacking is also observed [shortest centroid-centroid separation = 3.3394 (19) Å].

  8. Crystal structure of 2-[12-methyl-14-phenyl-10,13,14,16-tetra-aza-tetra-cyclo[7.7.0.0(2,7).0(11,15)]hexa-deca-1(16),2,4,6,9,11(15),12-heptaen-8-yl-idene]propandi-nitrile.

    PubMed

    Mague, Joel T; Mohamed, Shaaban K; Akkurt, Mehmet; El-Kashef, Hussein M S; Albayati, Mustafa R

    2014-12-01

    In the title mol-ecule, C22H12N6, the fused tetracyclic core shows a small lengthwise twist as indicated by the dihedral of 2.7 (2)° between the outer rings. In the crystal, mol-ecules stack along the b-axis direction via offset π-stacking [centroid-centroid distances = 3.5282 (13) and 3.5597 (14) Å] with the stacks weakly associated through C-H⋯N hydrogen bonds. The phenyl ring is rotationally disordered over two orientations with an occupancy ratio of 0.516 (4):0.484 (4).

  9. Crystal structure of 2-phenyl-2λ(4),3-ditellura-tetra-cyclo-[5.5.2.0(4,13).0(10,14)]tetra-deca-1(12),4,6,10,13-pentaen-2-ylium tri-fluoro-methane-sulfonate.

    PubMed

    Diamond, Louise M; Slawin, Alexandra M Z; Woollins, J Derek

    2014-09-01

    In the title compound, C18H13Te2 (+)·CF3O3S(-), the Te(II) atom of the cation and one O atom of the tri-fluoro-methane-sulfonate counter-ion form a close-to-linear Te-Te-O system, with a Te-Te-O angle of 172.3 (1)° and a Te-O distance of 2.816 (5) Å, which may suggest the presence of a three-centre-four-electron (3c-4e) bond. Secondary Te⋯O inter-actions [3.003 (4) and 3.016 (4) Å], involving the second Te(II) atom of the binuclear mol-ecule, are also noted, resulting in a supra-molecular layer in the bc plane.

  10. Efficient Conduct of Individual Flights and Air Traffic or Optimum Utilization of Modern Technology for the Overall Benefit of Civil and Military Airspace Users. Conference Proceedings of the Symposium of the Guidance and Control Panel (42nd) Held in Brussels, Belgium on 10-13 June 1986.

    DTIC Science & Technology

    1986-12-01

    Los divers partis on prisence difendent chacun leurs inti- rits comme il est naturel . La some des 6golsmes particuliers itant raroment igale S...caract~ristiques des centrales inertielles classiques sont bien connues, et la description de leurs erreurs instrumentales (erreurs des capteurs ) et des...dire ce qui suit de la centrale inertielle classique: - lea erreurs de sea capteurs ("erreurs instrumentales") peuvent se r~sumer h six valeurs, dont

  11. Crystal structure of trans-(1,8-dibutyl-1,3,6,8,10,13-hexa­aza­cyclo­tetra­decane-κ4 N 3,N 6,N 10,N 13)bis­(perchlorato-κO)copper(II) from synchrotron data

    PubMed Central

    Kim, Dae-Woong; Shin, Jong Won; Moon, Dohyun

    2015-01-01

    The structure of the title compound, [Cu(ClO4)2(C16H38N6)] has been determined from synchrotron data, λ = 0.62988 Å. The asymmetric unit comprises one half of the CuII complex as the CuII cation lies on an inversion center. It is coordinated by the four secondary N atoms of the macrocyclic ligand and the mutually trans O atoms of the two perchlorate ions in a tetra­gonally distorted octa­hedral geometry. The average equatorial Cu—N bond length is significantly shorter than the average axial Cu—O bond length [2.010 (4) and 2.569 (1) Å, respectively]. Intra­molecular N—H⋯O hydrogen bonds between the macrocyclic ligand and uncoordinating O atoms of the perchlorate ligand stabilize the mol­ecular structure. In the crystal structure, an extensive series of inter­molecular N—H⋯O and C—H⋯O hydrogen bonds generate a three-dimensional network. PMID:25878801

  12. Crystal structure of trans-(1,8-dibutyl-1,3,6,8,10,13-hexa­aza­cyclo­tetra­decane-κ4 N 3,N 6,N 10,N 13)bis­(thio­cyanato-κN)nickel(II) from synchrotron data

    PubMed Central

    Kim, Dae-Woong; Kim, Jong Jin; Shin, Jong Won; Kim, Jin Hong; Moon, Dohyun

    2015-01-01

    The crystal structure of the title compound, [Ni(NCS)2(C16H38N6)], has been determined from synchrotron data. The asymmetric unit consists of two halves of the complex mol­ecules which have their NiII atoms located on inversion centres. The NiII ions show a tetra­gonally distorted octa­hedral coordination geometry, with four secondary amine N atoms of the aza­macrocyclic ligand in the equatorial plane and two N atoms of the thio­cyanate anions in the axial positions. The average equatorial Ni—N bond length [2.070 (5) Å] is shorter than the average axial Ni—N bond length [2.107 (18) Å]. Only half of the macrocyclic ligand N—H groups are involved in hydrogen bonding. The complex mol­ecules are connected via inter­molecular N—H⋯S hydrogen bonds into two symmetry-independent one-dimensional polymeric structures extending along the b-axis direction. One of the n-butyl substituents of the macrocycle exhibits conformational disorder with a refined occupancy ratio of 0.630:0.370. PMID:26279866

  13. Absorption Oscillator Strengths for the c4‧1Σu+(3, 4, 6)-X1Σg+(v‧‧), b‧1Σu+(10, 13, 20)-X1Σg+(v‧‧), and c5‧1Σu+(1)-X1Σg+(v‧‧) Progressions in N2

    NASA Astrophysics Data System (ADS)

    Lavín, C.; Velasco, A. M.

    2016-01-01

    Absorption oscillator strengths, calculated with the molecular quantum defect orbital method, for the c4'1 Σu+(3)-X1Σg+ (v'' = 0-12), c4'1Σu+(4) -X1Σg+(v'' = 0-12), c4'1Σu+(6) -X1Σg+(v'' = 0-12), b'1Σu+(10) -X1Σg+(v'' = 0-12), b'1Σu+(13) -X1Σg+(v'' = 0-12), b'1Σu+(20) -X1Σg+(v'' = 0-12), and c5'1Σu+(1) -X1Σg+(v'' = 0-12) bands of molecular nitrogen are reported. The Rydberg-valence interaction between states of 1Σu+ symmetry has been treated through an interaction matrix that includes vibrational coupling. Due to the homogeneous interaction, the intensity distribution of the bands within each progression deviates from the Franck-Condon predictions. The present results for vibronic transitions from the X1Σg+(0) ground state agree rather well with reported high-resolution measurements. As far as we know, f-values for bands originating from v″ > 0 vibrational levels of the electronic ground state are reported here for the first time. These data may be useful in the interpretation of the extreme ultraviolet spectra from Earth’s and Titan's atmospheres, in which several bands of the c4'(3), c4', and c4'(6) progressions have been identified.

  14. Bis{4′-[(2,3,5,6,8,9,11,12-octa­hydro-1,4,7,10,13-benzopenta­oxacyclo­penta­decin-15-yl)meth­oxy]-2,2′:6′,2′′-terpyridine}cadmium(II) bis­(hexa­fluorido­phosphate) trihydrate: a powder study

    PubMed Central

    Kurochkina, Nadezhda M.; Kuzovlev, Andrey S.; Puryaeva, Tamara P.; Velikodny, Yurii A.; Chernyshev, Vladimir V.

    2009-01-01

    The asymmetric unit of the title compound, [Cd(C30H31N3O6)2](PF6)2·3H2O, contains one half-cation with the CdII center situated on a twofold rotational axis, one hexa­fluoridophosphate anion and two uncoordinated water mol­ecules, one of which is also situated on a twofold rotational axis. The cations are associated into columns along the a axis through π–π inter­actions between the pyridine and benzene rings, with a centroid–centroid distance of 3.72 (5) Å. Inter­molecular O—H⋯O, C—H⋯O and C—H⋯F hydrogen bonds consolidate the crystal packing. PMID:21578105

  15. 17-(5-Ethyl-6-methyl-heptan-2-yl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetra-deca-hydro-1H-cyclo-penta[a]phenanthrene-3,7-diol from Chisocheton tomentosus (Meliaceae).

    PubMed

    Najmuldeen, Ibrahim A; Hadi, Abdul Hamid Abdul; Awang, Khalijah; Mohamad, Khalit; Ng, Seik Weng

    2008-10-22

    The asymmetric unit of the title compound, C(29)H(50)O(2), contains two mol-ecules; one mol-ecule is linked to the other by two O-H⋯O hydrogen bonds, whereas only one of the hydr-oxy groups of the second mol-ecule is involved in hydrogen bonding. This gives rise to a chain that runs along the a axis of the monoclinic unit cell.

  16. Radiative association of He(23P) with lithium cations: Π → Σ processes

    NASA Astrophysics Data System (ADS)

    Zámečníková, Martina; Kraemer, Wolfgang P.; Soldán, Pavel

    2017-04-01

    The radiative association processes originating in the 13 Π continuum of the He (23 P) +Li+ collisional system are investigated in this study. The calculations of the dynamic collision processes are based on highly accurate state-of-the-art ab initio calculations of the potential energy functions for the 13 Π and the three lowest 3Σ states of HeLi+ and the associated transition dipole-moment functions. Cross-sections for the spontaneous and stimulated radiative association processes are calculated as functions of collision energy. The corresponding rate coefficients characterizing the efficiency of the formation of the molecular ion in its a3Σ+ , b3Σ+ , and c3Σ+ states from the initial 13 Π state are obtained over a wide range of temperatures. At very low temperatures the 1 → b process has a maximum rate-coefficient value of about 7.9 ×10-13cm3s-1 , whereas process 1 → a reaches its maximum value of 2.0 ×10-13cm3s-1 at a temperature of about 500 K. Altogether the three radiative association processes investigated here can be considered as the continuum-to-bound state radiative transition part of the total quenching of the initial collision channel.

  17. LIF studies of iodine oxide chemistry. Part 3. Reactions IO + NO3 --> OIO + NO2, I + NO3 --> IO + NO2, and CH2I + O2 --> (products): implications for the chemistry of the marine atmosphere at night.

    PubMed

    Dillon, Terry J; Tucceri, María E; Sander, Rolf; Crowley, John N

    2008-03-21

    The technique of pulsed laser photolysis coupled to LIF detection of IO was used to study IO + NO(3) --> OIO + NO(2); I + NO(3) --> (products); CH(2)I + O(2) --> (products); and O((3)P) + CH(2)I(2) --> IO + CH(2)I, at ambient temperature. was observed for the first time in the laboratory and a rate coefficient of k(1 a) = (9 +/- 4) x 10(-12) cm(3) molecule(-1) s(-1) obtained. For , a value of k(2) (298 K) = (1.0 +/- 0.3) x 10(-10) cm(3) molecule(-1) s(-1) was obtained, and a IO product yield close to unity determined. IO was also formed in a close-to-unity yield in , whereas in an upper limit of alpha(3)(IO) < 0.12 was derived. The implications of these results for the nighttime chemistry of the atmosphere were discussed. Box model calculations showed that efficient OIO formation in was necessary to explain field observations of large OIO/IO ratios.

  18. Gas-phase reaction between calcium monocation and fluoromethane: Analysis of the potential energy hypersurface and kinetics calculations.

    PubMed

    Varela-Alvarez, Adrián; Rayón, V M; Redondo, P; Barrientos, C; Sordo, José A

    2009-10-14

    The gas-phase reaction between calcium monocation and fluoromethane: Ca(+)+CH(3)F-->CaF(+)+CH(3) was theoretically analyzed. The potential energy hypersurface was explored by using density functional theory methodology with different functionals and Pople's, Dunning's, Ahlrichs', and Stuttgart-Dresden basis sets. Kinetics calculations (energy and total angular momentum resolved microcanonical variational/conventional theory) were accomplished. The theoretically predicted range for the global kinetic rate constant values at 295 K (7.2x10(-11)-5.9x10(-10) cm(3) molecule(-1) s(-1)) agrees reasonably well with the experimental value at the same temperature [(2.6+/-0.8)x10(-10) cm(3) molecule(-1) s(-1)]. Explicit consideration of a two transition state model, where the formation of a weakly bounded prereactive complex is preceded by an outer transition state (entrance channel) and followed by an inner transition state connecting with a second intermediate that finally leads to products, is mandatory. Experimental observations on the correlation, or lack of correlation, between reaction rate constants and second ionization energies of the metal might well be rationalized in terms of this two transition state model.

  19. Gas-phase reaction of methyl isothiocyanate and methyl isocyanate with hydroxyl radicals under static relative rate conditions.

    PubMed

    Lu, Zhou; Hebert, Vincent R; Miller, Glenn C

    2014-02-26

    Gaseous methyl isothiocyanate (MITC), the principal breakdown product of the soil fumigant metam sodium (sodium N-methyldithiocarbamate), is an inhalation exposure concern to persons living near treated areas. Inhalation exposure also involves gaseous methyl isocyanate (MIC), a highly reactive and toxic transformation product of MITC. In this work, gas-phase hydroxyl (OH) radical reaction rate constants of MITC and MIC have been determined using a static relative rate technique under controlled laboratory conditions. The rate constants obtained are 15.36 × 10(-12) cm(3) molecule(-1) s(-1) for MITC and 3.62 × 10(-12) cm(3) molecule(-1) s(-1) for MIC. The average half-lives of MITC and MIC in the atmosphere are estimated to be 15.7 and 66.5 h, respectively. The molar conversion of MITC to MIC for OH radical reactions is 67% ± 8%, which indicates that MIC is the primary product of the MITC-OH reaction in the gas phase.

  20. A multilayered-representation quantum mechanical/molecular mechanics study of the SN2 reaction of CH3Br + OH- in aqueous solution

    NASA Astrophysics Data System (ADS)

    Xu, Yulong; Wang, Tingting; Wang, Dunyou

    2012-11-01

    The bimolecular nucleophilic substitution (SN2) reaction of CH3Br and OH- in aqueous solution was investigated using a multilayered-representation quantum mechanical and molecular mechanics methodology. Reactant complex, transition state, and product complex are identified and characterized in aqueous solution. The potentials of mean force are computed under both the density function theory and coupled-cluster single double (triple) (CCSD(T)) levels of theory for the reaction region. The results show that the aqueous environment has a significant impact on the reaction process. The solvation effect and the polarization effect combined raise the activation barrier height by ˜16.2 kcal/mol and the solvation effect is the dominant contribution to the potential of mean force. The CCSD(T)/MM representation presents a free energy activation barrier height of 22.8 kcal/mol and the rate constant at 298 K of 3.7 × 10-25 cm3 molecule-1 s-1 which agree very well with the experiment values at 23.0 kcal/mol and 2.6 × 10-25 cm3 molecule-1 s-1, respectively.

  1. Direct experimental probing and theoretical analysis of the reaction between the simplest Criegee intermediate CH2OO and isoprene.

    PubMed

    Decker, Z C J; Au, K; Vereecken, L; Sheps, L

    2017-03-13

    Recent advances in the spectroscopy of Criegee intermediates (CI) have enabled direct kinetic studies of these highly reactive chemical species. The impact of CI chemistry is currently being incorporated into atmospheric models, including their reactions with trace organic and inorganic compounds. Isoprene, C5H8, is a doubly-unsaturated hydrocarbon that accounts for the largest share of all biogenic emissions around the globe and is also a building block of larger volatile organic compounds. We report direct measurements of the reaction of the simplest CI (CH2OO) with isoprene, using time-resolved cavity-enhanced UV absorption spectroscopy. We find the reaction to be pressure-independent between 15-100 Torr, with a rate coefficient that varies from (1.5 ± 0.1) × 10(-15) cm(3) molecule(-1) s(-1) at room temperature to (23 ± 2) × 10(-15) cm(3) molecule(-1) s(-1) at 540 K. Quantum chemical and transition-state theory calculations of 16 unique channels for CH2OO + isoprene somewhat underpredict the observed T-dependence of the total reaction rate coefficient, but are overall in good agreement with the experimental measurements. This reaction is broadly similar to those with smaller alkenes, proceeding by 1,3-dipolar cycloaddition to one of the two conjugated double bonds of isoprene.

  2. Direct Determination of the Simplest Criegee Intermediate (CH2OO) Self Reaction Rate.

    PubMed

    Buras, Zachary J; Elsamra, Rehab M I; Green, William H

    2014-07-03

    The rate of self-reaction of the simplest Criegee intermediate, CH2OO, is of importance in many current laboratory experiments where CH2OO concentrations are high, such as flash photolysis and alkene ozonolysis. Using laser flash photolysis while simultaneously probing both CH2OO and I atom by direct absorption, we can accurately determine absolute CH2OO concentrations as well as the UV absorption cross section of CH2OO at our probe wavelength (λ = 375 nm), which is in agreement with a recently published value. Knowing absolute concentrations we can accurately measure kself = 6.0 ± 2.1 × 10(-11)cm(3) molecule(-1) s(-1) at 297 K. We are also able to put an upper bound on the rate coefficient for CH2OO + I of 1.0 × 10(-11) cm(3) molecule(-1) s(-1). Both of these rate coefficients are at least a factor of 5 smaller than other recent measurements of the same reactions.

  3. Measuring rate constants for reactions of the simplest Criegee intermediate (CH2OO) by monitoring the OH radical.

    PubMed

    Liu, Yingdi; Bayes, Kyle D; Sander, Stanley P

    2014-01-30

    While generating the CH2OO molecule by reacting CH2I with O2, significant amounts of the OH radical were observed by laser-induced fluorescence. At least two different processes formed OH. A fast process was probably initiated by a reaction of vibrationally hot CH2I radicals. The second process appeared to be associated with the decay of the CH2OO molecule. The addition of molecules known to react with CH2OO increased the observed decay rates of the OH signal. Using the OH signals as a proxy for the CH2OO concentration, the rate constant for the reaction of hexafluoroacetone with CH2OO was determined to be (3.33 ± 0.27) × 10(-11) cm(3) molecule(-1) s(-1), in good agreement with the value measured by Taatjes et al.1 The rate constant for the reaction of SO2 with CH2OO, (3.53 ± 0.29) × 10(-11) cm(3) molecule(-1) s(-1), showed no pressure dependence over the range of 50-200 Torr and was in agreement with the value at 4 Torr reported by Welz et al.

  4. Formation, thermal decomposition and atmospheric implications of the CF2(OH)CF2OONO2 and CF3CF2OONO2 peroxynitrates. A theoretical study

    NASA Astrophysics Data System (ADS)

    Badenes, María Paula

    2017-04-01

    A SACM/CT study of the CF2(OH)CF2OO + NO2 → CF2(OH)CF2OONO2 and CF3CF2OO + NO2 → CF3CF2OONO2 recombination reactions and their reverse unimolecular decomposition process was performed. The electronic energy along the reaction pathways was calculated at the G4(MP2) level. High-pressure rate coefficients of 1.53 × 10-12 (T/300)0.37 cm3 molecule-1 s-1 and 1.79 × 1016 (T/300)0.40 exp(-24.4 kcal mol-1/RT) s-1 were derived at 200-300 K for the direct and backward reactions of CF2(OH)CF2OONO2, while for CF3CF2OONO2, the expressions 1.01 × 10-12 (T/300)0.39 cm3 molecule-1 s-1 and 1.05 × 1016 (T/300)0.44 exp(-23.0 kcal mol-1/RT) s-1 were obtained. A decomposition lifetime profile was derived for CF2(OH)CF2OONO2, indicating that it could act as transport and reservoir of CF2(OH)CF2OO and NO2 in the stratosphere.

  5. Rate and mechanism of the reactions of OH and Cl with 2-methyl-3-buten-2-ol

    NASA Astrophysics Data System (ADS)

    Ferronato, C.; Orlando, J. J.; Tyndall, G. S.

    1998-10-01

    An environmental chamber/Fourier transform infrared system was used to determine the rate coefficient k1 for the gas-phase reaction of OH with 2-methyl-3-buten-2-ol (MBO, (CH3)2C(OH)CH=CH2), relative to the rate of its reaction with ethylene (k2) and propylene (k3). Experiments performed at 295±1 K, in 700 torr total pressure of air, gave k1 = (6.9±1.0) × 10-11 cm3 molecule-1 s-1. At 295±1 K, the reaction of OH with MBO yielded, on a per mole basis, (52±5)% acetone, (50±5)% glycolaldehyde, and (35±4)% formaldehyde. The production of acetone from the oxidation of MBO may be of significance globally. The kinetics and mechanism of the reaction of chlorine atoms with MBO (k15) have also been studied at 700 torr total pressure of air and 295±1 K. The rate coefficient was determined using a relative rate technique, with ethane (k16), ethylene (k17), and cyclohexane (k18) as reference compounds. The value of k15 was found to be (3.3±0.4) × 10-10 cm3 molecule-1 s-1 at 295 K. The major carbon-containing products obtained in the Cl-atom oxidation of MBO were acetone (47±5)%, chloroacetaldehyde (53±5)%, HCOCl (<11%), and formaldehyde (6 ± 2)%.

  6. Heterogeneous reactivity of pyrene and 1-nitropyrene with NO 2: Kinetics, product yields and mechanism

    NASA Astrophysics Data System (ADS)

    Miet, K.; Le Menach, K.; Flaud, P.-M.; Budzinski, H.; Villenave, E.

    The heterogeneous reactivity of nitrogen dioxide with pyrene and 1-nitropyrene (1NP) adsorbed on silica particles has been investigated using a fast-flow-tube in the absence of light. Reactants and products were extracted from particles using pressurised fluid extraction (PFE) and concentration measurements were performed using gas chromatography/mass spectrometry (GC/MS). The pseudo-first order rate constants were obtained from the fit of the experimental decay of particulate polycyclic compound concentrations versus reaction time. Experiments were performed at three different NO 2 concentrations and second order rate constants were calculated considering the oxidant concentration. The following rate constant values were obtained at room temperature: k(NO 2 + pyrene) = (9.3 ± 2.3) × 10 -17 cm 3 molecule -1 s -1 and k(NO 2 + 1NP) = (6.2 ± 1.5) × 10 -18 cm 3 molecule -1 s -1, showing that the reactivity of 1NP was slower by a factor of 15 than that of pyrene. 1NP was identified as the only NO 2-initiated oxidation product of pyrene and all the three dinitropyrenes were identified in the case of the 1NP reaction. The product quantification allowed showing that the kinetics of oxidation product formation was equal to that measured for parent compounds degradation, within uncertainties, confirming the validity of the reaction kinetics measurements.

  7. Influence of temperature in the kinetics of the gas-phase reactions of a series of acetates with Cl atoms

    NASA Astrophysics Data System (ADS)

    Cuevas, Carlos A.; Notario, Alberto; Martínez, Ernesto; Albaladejo, José

    Absolute rate coefficients have been measured for the first time as a function of temperature for the gas phase reactions of chlorine atoms with a series of aliphatic acetates: methyl acetate ( k1), ethyl acetate ( k2), n-propyl acetate ( k3) and n-butyl acetate ( k4). The experiments were carried out using the pulsed laser photolysis-resonance fluorescence technique (PLP-RF), over the temperature range 265-383 K. The obtained kinetic data were used to derive the Arrhenius expressions: k1=(9.31±1.02)×10-12exp[-(359±70)/T]; k2=(4.35±0.65)×10-12exp[(342±92)/T]; k3=(2.22±0.20)×10-11exp[(217±58)/T] and k4=(5.41±1.51)×10-11exp[(245±168)/T] (in units of cm 3 molecule -1 s -1). The rate constants obtained at room temperature were as follows: methyl acetate, 0.279±0.031; ethyl acetate, 1.37±0.20; n-propyl acetate, 4.60±0.41 and n-butyl acetate, 12.3±3.4 (in units 10 -11 cm 3 molecule -1 s -1). The results are discussed in terms of structure-reactivity relationships and the atmospherics implications are also analyzed.

  8. The gas-phase degradation of chlorpyrifos and chlorpyrifos-oxon towards OH radical under atmospheric conditions.

    PubMed

    Muñoz, Amalia; Ródenas, Milagros; Borrás, Esther; Vázquez, Mónica; Vera, Teresa

    2014-09-01

    The OH initiated oxidation of chlorpyrifos (a widely used insecticide) and its photooxidation product chlorpyrifos-oxon were investigated at the large outdoor European Photoreactor (EUPHORE). The rate constants for reaction of chlorpyrifos and chlorpyrifos oxon with OH radicals were measured using a conventional relative rate method. The value of the OH reaction rate constants with chlorpyrifos and chlorpyrifos-oxon were determined to be k=(9.1±2.1)×10(-11)cm(3)molecule(-1)s(-1) and (1.7±0.9)×10(-11)cm(3)molecule(-1)s(-1) at 303±5K and atmospheric pressure. They gave an atmospheric lifetime in relation to the reaction with OH of approximately 2h and 11h for chlorpyrifos and chlorpyrifos-oxon, respectively. Photolysis was found to be unimportant relative to reaction with OH. The main products detected in the gas phase from the reaction of OH with chlorpyrifos were SO2, chlorpyrifos-oxon, 3,5,6-trichloro-2-pyridinol and diethylphosphate with molar yields of 17±5%, ∼10%, 8±4% and 30±9%, respectively.

  9. Dissociative Recombination of FeO(+) with Electrons: Implications for Plasma Layers in the Ionosphere.

    PubMed

    Bones, D L; Plane, J M C; Feng, W

    2016-03-10

    The dissociative recombination (DR) of FeO(+) ions with electrons has been studied in a flowing afterglow reactor. FeO(+) was generated by the pulsed laser ablation of a solid Fe target, and then entrained in an Ar(+) ion/electron plasma where the absolute electron density was measured using a Langmuir probe. A kinetic model describing gas-phase chemistry and diffusion to the reactor walls was fitted to the experimental data, yielding a DR rate coefficient at 298 K of k(FeO(+) + e(-)) = (5.5 ± 1.0) × 10(-7) cm(3) molecule(-1) s(-1), where the quoted uncertainty is at the 2σ level. Fe(+) ions in the lower thermosphere are oxidized by O3 to FeO(+), and this DR reaction is shown to provide a more important route for neutralizing Fe(+) below 110 km than the radiative/dielectronic recombination of Fe(+) with electrons. The experimental system was first validated by measuring two other DR reaction rate coefficients: k(O2(+) + e(-)) = (2.0 ± 0.4) × 10(-7) and k(N2O(+) + e(-)) = (3.3 ± 0.8) × 10(-7) cm(3) molecule(-1) s(-1), which are in good agreement with the recent literature.

  10. Rate coefficients for the OH + pinonaldehyde (C10H16O2) reaction between 297 and 374 K.

    PubMed

    Davis, Maxine E; Talukdar, Ranajit K; Notte, Gregory; Ellison, G Barney; Burkholder, James B

    2007-06-01

    The rate coefficientforthe reaction of OH with pinonaldehyde (C10H16O2, 3-acetyl-2,2-dimethyl-cyclobutyl-ethanal), a product of the atmospheric oxidation of alpha-pinene, was measured under pseudo-first-order conditions in OH at temperatures between 297 and 374 K at 55 and 96 Torr (He). Laser induced fluorescence (LIF) was used to monitor OH in the presence of pinonaldehyde following its production by 248 nm pulsed laser photolysis of H2O2. The reaction exhibits a negative temperature dependence with an Arrhenius expression of k1(T) = (4.5 +/- 1.3) x 10(-12) exp((600 +/- 100)/ 7) cm3 molecule(-1) s(-1); k1(297 K) = (3.46 +/- 0.4) x 10(-11) cm3 molecule(-1) s(-1). There was no observed dependence of the rate coefficient on pressure. Our results are compared with previous relative rate determinations of k1 near 297 K and the discrepancies are discussed. The state of knowledge for the atmospheric processing of pinonaldehyde is reviewed, and its role as a marker for alpha-pinene (monoterpene) chemistry in the atmosphere is discussed.

  11. Kinetics study of reactions of α-pinene and β-pinene with hydroxyl radical at 1-8 Torr and 240-340 K using the relative rate/discharge flow/mass spectrometry method.

    PubMed

    Montenegro, Anthony; Ishibashi, Jacob S A; Lam, Phuong; Li, Zhuangjie

    2012-12-13

    The kinetics of reactions of α-pinene and β-pinene with hydroxyl radicals (OH) has been investigated at 1-8 Torr and 240-340 K using the relative rate/discharge flow/mass spectrometry (RR/DF/MS) technique. Our kinetic results indicate that at 298 K the rate constant of the reactions of α-pinene and β-pinene with hydroxyl radicals has little pressure dependence over the 1-8 Torr pressure range, suggesting that the high pressure limit of these reactions has been reached at 1 Torr. The rate constant of these reactions was found to negatively depend on the temperature at 240-340 K, which is consistent with previous investigations using different techniques. The Arrhenius equation for α-pinene and β-pinene with hydroxyl radical was determined to be k(α-pinene) = (1.21 ± 0.20) × 10(-11)exp[(441 ± 46)/T] cm(3) molecule(-1) s(-1) and k(β-pinene) = (1.65 ± 0.10) × 10(-11)exp[(470 ± 17)/T] cm(3) molecule(-1) s(-1), respectively. Using the rate constant determined at 277 K in this work and the average global hydroxyl radical concentration, the atmospheric lifetime of α-pinene and β-pinene was estimated to be 5.8 and 3.8 h, respectively.

  12. Atmospheric Vinyl Alcohol to Acetaldehyde Tautomerization Revisited.

    PubMed

    Peeters, Jozef; Nguyen, Vinh Son; Müller, Jean-François

    2015-10-15

    The atmospheric oxidation of vinyl alcohol (VA) produced by photoisomerization of acetaldehyde (AA) is thought to be a source of formic acid (FA). Nevertheless, a recent theoretical study predicted a high rate coefficient k1(298 K) of ≈10(-14) cm(3) molecule(-1) s(-1) for the FA-catalyzed tautomerization reaction 1 of VA back into AA, which suggests that FA buffers its own production from VA. However, the unusually high frequency factor implied by that study prompted us to reinvestigate reaction 1 . On the basis of a high-level ab initio potential energy profile, we first established that transition state theory is applicable, and derived a k1(298 K) of only ≈2 × 10(-20) cm(3) molecule(-1) s(-1), concluding that the reaction is negligible. Instead, we propose and rationalize another important VA sink: its uptake by aqueous aerosol and cloud droplets followed by fast liquid-phase tautomerization to AA; global modeling puts the average lifetime by this sink at a few hours, similar to oxidation by OH.

  13. Rate parameters for the reaction of atomic hydrogen with dimethyl ether and dimethyl sulfide

    NASA Astrophysics Data System (ADS)

    Lee, J. H.; Machen, R. C.; Nava, D. F.; Stief, L. J.

    1981-03-01

    Absolute rate constants for the reaction of atomic hydrogen with dimethyl ether (DME) and dimethyl sulfide (DMS) were obtained using the flash photolysis-resonance fluorescence technique. Under conditions where secondary reactions are avoided, rate constants for the H+DME reaction over the temperature range 273-426 K are well represented by the Arrhenius expression k1=(4.38±0.59)×10-12 exp(-1956±43/T) cm3 molecule-1 s-1. The corresponding Arrhenius expression for the H+DMS reaction over the temperature range 212-500 K is k2=(1.30±0.43)×10-11exp(-1118±81/T) cm3 molecule-1 s-1. The Arrhenius plot for k2 shows signs of curvature, however, and separate Arrhenius expressions are derived for the data above and below room temperature. These results are discussed and comparisons are made with previous determinations which employed flow discharge and product analysis techniques.

  14. Hydroxyl radical reaction rate coefficients as a function of temperature and IR absorption cross sections for CF3CH=CH2 (HFO-1243zf), potential replacement of CF3CH2F (HFC-134a).

    PubMed

    González, Sergio; Jiménez, Elena; Ballesteros, Bernabé; Martínez, Ernesto; Albaladejo, José

    2015-04-01

    CF3CH=CH2 (hydrofluoroolefin, HFO-1243zf) is a potential replacement of high global-warming potential (GWP) hydrofluorocarbon (HFC-134a, CF3CFH2). Both the atmospheric lifetime and the radiative efficiency of HFO-1243zf are parameters needed for estimating the GWP of this species. Therefore, the aim of this work is (i) to estimate the atmospheric lifetime of HFO-1243zf from the reported OH rate coefficients, k OH, determined under tropospheric conditions and (ii) to calculate its radiative efficiency from the reported IR absorption cross sections. The OH rate coefficient at 298 K also allows the estimation of the photochemical ozone creation potential (ε(POCP)). The pulsed laser photolysis coupled to a laser-induced fluorescence technique was used to determine k OH for the reaction of OH radicals with HFO-1243zf as a function of pressure (50-650 Torr of He) and temperature (263-358 K). Gas-phase IR spectra of HFO-1243zf were recorded at room temperature using a Fourier transform IR spectrometer between 500 and 4,000 cm(-1). At all temperatures, k OH did not depend on bath gas concentration (i.e., on the total pressure between 50 and 650 Torr of He). A slight but noticeable T dependence of k OH was observed in the temperature range investigated. The observed behavior is well described by the following Arrhenius expression: k OH(T) = (7.65 ± 0.26) × 10(-13) exp [(165 ± 10) / T] cm(3) molecule(-1) s(-1). Negligible IR absorption of HFO-1243zf was observed at wavenumbers greater than 1,700 cm(-1). Therefore, IR absorption cross sections, [Formula: see text], were determined in the 500-1,700 cm(-1) range. Integrated [Formula: see text] were determined between 650 and 1,800 cm(-1) for comparison purposes. The main diurnal removal pathway for HFO-1243zf is the reaction with OH radicals, which accounts for 64% of the overall loss by homogeneous reactions at 298 K. Globally, the lifetime due to OH reaction (τ OH) was estimated to be 8.7 days under

  15. Gas-phase tropospheric chemistry of 2,3,7,8-tetrafuorinated dibenzo-p-dioxin.

    PubMed

    Zhang, Chenxi; Sun, Xiaomin

    2014-01-15

    Growing attention has been devoted to understanding the formation and destruction of polyfluorinated dibenzo-p-dioxins (PFDDs). High-accuracy molecular orbital calculations have been performed to investigate the tropospheric oxidation reaction of 2,3,7,8-tetrafuorinated dibenzo-p-dioxin (TFDD) initiated by OH radical, NO3 radical and O3. The rate constant of TFDD reaction triggered by the OH radical, NO3 radical and O3 is about 2.30 × 10(-11)cm(3) molecule(-l) s(-l), 3.18 × 10(-13)cm(3) molecule(-l) s(-l), and 3.30 × 10(-19)cm(3) molecule(-l) s(-l), respectively. OH radical is the major gas phase tropospheric sink for TFDD. Once TFDD-OH intermediates are produced in the initial reactions, they can react with tropospheric O2 subsequently to generate peroxy radical isomers. The TFDD-OH-O2 can further react with tropospheric NO via isomerization or combination, resulting that the dioxin ring will be ruptured completely. This study can serve as a template for tropospheric degradation of the gaseous PFDDs, which is beneficial for assessing their tropospheric behaviors.

  16. Laser initiation and decay processes in an organic vapor plasma

    NASA Astrophysics Data System (ADS)

    Ding, Guowen

    A large volume organic molecular plasma (hundreds of cm3) is created by a 193 nm laser ionizing an organic molecule, Tetrakis-(dimethylamino)-ethylene (TMAE). The plasma is found to be characterized by high electron density (10 13-1011cm-3), low electron temperature (~0.1 eV), fast creation (~10 ns) and rapid decaying (electron-ion recombination coefficient ~10-6 cm3/s). Fast Langmuir probe (LP) techniques are developed for diagnosing this plasma, including a novel probe design and fabrication, a fast detection system, sampling, indirect probe heating, electro-magnetic shielding and dummy probe techniques. Plasma physical processes regarding fast LP diagnostics for different time scales (t> and <100 ns) are studied. A theory for the correction due to a rapidly decaying plasma to LP measurements is developed. The mechanisms responsible for the plasma decay are studied, and a delayed ionization process is found to be important in interpreting the decay processes. It is also found that nitrogen can enhance the delayed emission of a TMAE Rydberg state from the TMAE plasma. This result strongly suggests that a long-lifetime highly-excited state is important in the TMAE plasma decay process. This result supports the delayed ionization mechanism. A model combining electron-ion recombination and delayed ionization processes is developed to calculate the delayed ionization lifetime.

  17. A Kinetic and Product Study of the Cl + HO2 Reaction

    NASA Technical Reports Server (NTRS)

    Hickson, Kevin M.; Keyser, Leon F.

    2005-01-01

    Absolute rate data and product branching ratios for the reactions Cl + HO2 to HCl + O2 (k1a) and Cl + HO2 to OH + ClO (k1b) have been measured from 226 to 336 K at a total pressure of 1 Torr of helium using the discharge flow resonance fluorescence technique coupled with infrared diode laser spectroscopy. For kinetic measurements, pseudo-first-order conditions were used with both reagents in excess in separate experiments. HO2 was produced by two methods: through the termolecular reaction of H atoms with O2 and also by the reaction of F atoms with H2O2. Cl atoms were produced by a microwave discharge of Cl2 in He. HO2 radicals were converted to OH radicals prior to detection by resonance fluorescence at 308 nm. Cl atoms were detected directly at 138 nm also by resonance fluorescence. Measurement of the consumption of HO2 in excess Cl yielded k1a and measurement of the consumption of Cl in excess HO2 yielded the total rate coefficient, k1. Values of k1a and k1 derived from kinetic experiments expressed in Arrhenius form are (1.6 +/- 0.2) x 10-11 exp[(249 +/- 34)/T] and (2.8 +/- 0.1) x 10-11 exp[(123 +/- 15)/T] cm3 molecule-1 s-1, respectively. As the expression for k1 is only weakly temperature dependent, we report a temperature-independent value of k1 = (4.5 +/- 0.4) x 10-11 cm3 molecule-1 s-1. Additionally, an Arrhenius expression for k1b can also be derived: k1b = (7.7 +/- 0.8) x 10-11 exp[-(708 +/- 29)/T] cm3 molecule-1 s-1. These expressions for k1a and k1b are valid for 226 K T 336 and 256 K T 296 K, respectively. The cited errors are at the level of a single standard deviation. For the product measurements, an excess of Cl was added to known concentrations of HO2 and the reaction was allowed to reach completion. HCl product concentrations were determined by IR absorption yielding the ratio k1a/k1 over the temperature range 236 K T 296 K. OH product concentrations were determined by resonance fluorescence giving rise to the ratio k1b/k1 over the temperature

  18. Kinetics and products of the reaction of OH radicals with 3-methoxy-3-methyl-1-butanol.

    PubMed

    Aschmann, Sara M; Arey, Janet; Atkinson, Roger

    2011-08-15

    3-Methoxy-3-methyl-1-butanol [CH(3)OC(CH(3))(2)CH(2)CH(2)OH] is used as a solvent for paints, inks, and fragrances and as a raw material for the production of industrial detergents. A rate constant of (1.64 ± 0.18) × 10(-11) cm(3) molecule(-1) s(-1) for the reaction of 3-methoxy-3-methyl-1-butanol with OH radicals has been measured at 296 ± 2 K using a relative rate method, where the indicated error is the estimated overall uncertainty. Acetone, methyl acetate, glycolaldehyde, and 3-methoxy-3-methylbutanal were identified as products of the OH radical-initiated reaction, with molar formation yields of 3 ± 1%, 35 ± 9%, 13 ± 3%, and 33 ± 7%, respectively, at an average NO concentration of 1.3 × 10(14) molecules cm(-3). Using a 12-h average daytime OH radical concentration of 2 × 10(6) molecules cm(-3), the calculated lifetime of 3-methoxy-3-methyl-1-butanol with respect to reaction with OH radicals is 8.5 h. Potential reaction mechanisms are discussed.

  19. Atmospheric chemistry of propionaldehyde: kinetics and mechanisms of reactions with OH radicals and Cl atoms, UV spectrum, and self-reaction kinetics of CH3CH2C(O)O2 radicals at 298 K.

    PubMed

    Le Crâne, Jean-Paul; Villenave, Eric; Hurley, Michael D; Wallington, Timothy J; Ball, James C

    2005-12-29

    The kinetics and mechanism of the reactions of Cl atoms and OH radicals with CH3CH2CHO were investigated at room temperature using two complementary techniques: flash photolysis/UV absorption and continuous photolysis/FTIR smog chamber. Reaction with Cl atoms proceeds predominantly by abstraction of the aldehydic hydrogen atom to form acyl radicals. FTIR measurements indicated that the acyl forming channel accounts for (88 +/- 5)%, while UV measurements indicated that the acyl forming channel accounts for (88 +/- 3)%. Relative rate methods were used to measure: k(Cl + CH3CH2CHO) = (1.20 +/- 0.23) x 10(-10); k(OH + CH3CH2CHO) = (1.82 +/- 0.23) x 10(-11); and k(Cl + CH3CH2C(O)Cl) = (1.64 +/- 0.22) x 10(-12) cm3 molecule(-1) s(-1). The UV spectrum of CH3CH2C(O)O2, rate constant for self-reaction, and rate constant for cross-reaction with CH3CH2O2 were determined: sigma(207 nm) = (6.71 +/- 0.19) x 10(-18) cm2 molecule(-1), k(CH3CH2C(O)O2 + CH3CH2C(O)O2) = (1.68 +/- 0.08) x 10(-11), and k(CH3CH2C(O)O2 + CH3CH2O2) = (1.20 +/- 0.06) x 10(-11) cm3 molecule(-1) s(-1), where quoted uncertainties only represent 2sigma statistical errors. The infrared spectrum of C2H5C(O)O2NO2 was recorded, and products of the Cl-initiated oxidation of CH3CH2CHO in the presence of O2 with, and without, NO(x) were identified. Results are discussed with respect to the atmospheric chemistry of propionaldehyde.

  20. Electron attachment to halomethanes at high temperature: CH2Cl2, CF2Cl2, CH3Cl, and CF3Cl attachment rate constants up to 1100 K

    NASA Astrophysics Data System (ADS)

    Miller, Thomas M.; Friedman, Jeffrey F.; Schaffer, Linda C.; Viggiano, A. A.

    2009-08-01

    We have used a high-temperature flowing-afterglow Langmuir-probe apparatus to measure rate constants for electron attachment to halomethanes which attach electrons very inefficiently at room temperature, yielding Cl- ion product. We studied CH2Cl2 (495-973 K), CF2Cl2 (291-1105 K), and CF3Cl (524-1004 K) and include our recent measurement for CH3Cl (700-1100 K) in the discussion of the electron attachment results. The measured attachment rate constants show Arrhenius behavior in the temperature ranges examined, from which estimates of rate constants at 300 K may be made: CH2Cl2 (1.8×10-13 cm3 s-1), CH3Cl (1.1×10-17 cm3 s-1), and CF3Cl (4.2×10-14 cm3 s-1), all of which are difficult to measure directly. In the case of CF2Cl2, the room temperature rate constant was sufficiently large to be measured (1.6×10-9 cm3 s-1). The Arrhenius plots yield activation energies for the attachment reactions: 390±50 meV (CH2Cl2), 124±20 meV (CF2Cl2), 670±70 meV (CH3Cl), and 406±50 meV (CF3Cl). Comparisons are made with existing data where available. G3 calculations were carried out to obtain reaction energetics. They show that the parent anions of CH2Cl2 CF2Cl2, CH3Cl, and CF3Cl are stable, though CH3Cl- exists only as an electrostatically bound complex.

  1. Electron attachment to halomethanes at high temperature: CH(2)Cl(2), CF(2)Cl(2), CH(3)Cl, and CF(3)Cl attachment rate constants up to 1100 K.

    PubMed

    Miller, Thomas M; Friedman, Jeffrey F; Schaffer, Linda C; Viggiano, A A

    2009-08-28

    We have used a high-temperature flowing-afterglow Langmuir-probe apparatus to measure rate constants for electron attachment to halomethanes which attach electrons very inefficiently at room temperature, yielding Cl(-) ion product. We studied CH(2)Cl(2) (495-973 K), CF(2)Cl(2) (291-1105 K), and CF(3)Cl (524-1004 K) and include our recent measurement for CH(3)Cl (700-1100 K) in the discussion of the electron attachment results. The measured attachment rate constants show Arrhenius behavior in the temperature ranges examined, from which estimates of rate constants at 300 K may be made: CH(2)Cl(2) (1.8x10(-13) cm(3) s(-1)), CH(3)Cl (1.1x10(-17) cm(3) s(-1)), and CF(3)Cl (4.2x10(-14) cm(3) s(-1)), all of which are difficult to measure directly. In the case of CF(2)Cl(2), the room temperature rate constant was sufficiently large to be measured (1.6x10(-9) cm(3) s(-1)). The Arrhenius plots yield activation energies for the attachment reactions: 390+/-50 meV (CH(2)Cl(2)), 124+/-20 meV (CF(2)Cl(2)), 670+/-70 meV (CH(3)Cl), and 406+/-50 meV (CF(3)Cl). Comparisons are made with existing data where available. G3 calculations were carried out to obtain reaction energetics. They show that the parent anions of CH(2)Cl(2) CF(2)Cl(2), CH(3)Cl, and CF(3)Cl are stable, though CH(3)Cl(-) exists only as an electrostatically bound complex.

  2. Kinetics and mechanism of the tropospheric oxidation of vinyl acetate initiated by OH radical: a theoretical study.

    PubMed

    Mandal, Debasish; Sahu, Chandan; Bagchi, Sabyasachi; Das, Abhijit K

    2013-05-09

    Vinyl acetate [VA (CH3COOC2H3)] is an important unsaturated and oxygenated volatile organic compound responsible for atmospheric pollution. In this work, possible reaction mechanisms for the degradation of OH-initiated atmospheric oxidation of VA are investigated. The potential energy surfaces (PESs) for the reaction of OH radical with VA in the presence of O2 and NO have been studied using the M06-2X/6-311++G(d,p) method. The initial addition reactions of more and less substituted ethylenic C-atoms of VA are treated separately, followed by a conventional transition state theory (TST) calculation for reaction rates. The direct H-abstraction mechanism and kinetics have also been studied. The initial OH addition occurs through a prereactive complex, and the calculated rate constants in the temperature range 250-350 K for both the addition reactions are found to have negative temperature dependence. The calculation indicates that the reaction proceeds predominantly via the addition of OH radical to the double bond rather than the direct abstraction of H-atoms in VA. IM1 [CH3C(O)O(•)CHCH2OH] and IM2 [CH3C(O)OCH(OH)(•)CH2], the OH adduct complexes formed initially, react with ubiquitous O2 followed by NO before their rearrangement. The formation of the prereactive complex plays an important role in reaction mechanism and kinetics. The calculated rate constant, k298K = 1.61 × 10(-11) cm(3) molecule(-1) s(-1), is well harmonized with the previous experimental data, k298K = (2.48 ± 0.61) × 10(-11) cm(3) molecule(-1) s(-1) (Blanco et al.) and k298K = (2.3 ± 0.3) × 10(-11) cm(3) molecule(-1) s(-1) (Picquet-Varrult et al.). Additionally, consistent and reliable enthalpies of formation at 298.15 K (ΔfH°298.15) have been computed for all the species involved in the title reaction using the composite CBS-QB3 method. The theoretical results confirm that the major products are formic acetic anhydride, acetic acid, and formaldehyde in the OH-initiated oxidation of VA in

  3. Temperature dependent kinetics (195-798 K) and H atom yields (298-498 K) from reactions of (1)CH(2) with acetylene, ethene, and propene.

    PubMed

    Gannon, K L; Blitz, M A; Liang, C H; Pilling, M J; Seakins, P W; Glowacki, D R

    2010-09-09

    The rate coefficients for the removal of the excited state of methylene, (1)CH(2) (a(1)A(1)), by acetylene, ethene, and propene have been studied over the temperature range 195-798 K by laser flash photolysis, with (1)CH(2) being monitored by laser-induced fluorescence. The rate coefficients of all three reactions exhibit a negative temperature dependence that can be parametrized as k((1)CH(2)+C(2)H(2)) = (3.06 +/- 0.11) x 10(-10) T ((-0.39+/-0.07)) cm(3) molecule(-1) s(-1), k((1)CH(2)+C(2)H(4)) = (2.10 +/- 0.18) x 10(-10) T ((-0.84+/-0.18)) cm(3) molecule(-1) s(-1), k((1)CH(2)+C(3)H(6)) = (3.21 +/- 0.02) x 10(-10) T ((-0.13+/-0.01)) cm(3) molecule(-1) s(-1), where the errors are statistical at the 2sigma level. Removal of (1)CH(2) occurs by chemical reaction and electronic relaxation to ground state triplet methylene. The H atom yields from the reactions of (1)CH(2) with acetylene, ethene, and propene have been determined by laser-induced fluorescence over the temperature range 298-498 K. For the reaction with propene, H atom yields are close to the detection limit, but for acetylene and ethene, the fraction of H atom production is approximately 0.88 and 0.71, respectively, at 298 K, rising to unity by 398 K, with the balance of the reaction with acetylene presumed to be electronic relaxation. Experimental constraints limit studies to a maximum of 1 Torr of bath gas; master equation calculations using an approach that allows treatment of intermediates with deep energy wells have been carried out to explore the role of collisional stabilization for the reaction of (1)CH(2) with acetylene. Stabilization is calculated to be insignificant under the experimental conditions, but does become significant at higher pressures. Between pressures of 100 and 1000 Torr, propyne and allene are formed in similar amounts with a slight preference for propyne. At higher pressures propyne formation becomes about a factor two greater than that of allene, and above 10(5) Torr (300 < T

  4. Tropospheric oxidation of cyclic unsaturated ethers in the day-time: Comparison of the reactions with Cl, OH and O3 based on the determination of their rate coefficients at 298 K

    NASA Astrophysics Data System (ADS)

    Alwe, H. D.; Walavalkar, M. P.; Sharma, A.; Dhanya, S.; Naik, P. D.

    2014-01-01

    The rate coefficients of the reactions of three unsaturated cyclic ethers, 2,5-dihydrofuran (2,5-DHF), 2,3-dihydrofuran (2,3-DHF), and 3,4-dihydropyran (3,4-DHP), with the major day-time tropospheric oxidants - OH (kOH) and O3(kO3), and that of 3,4-DHP with Cl atom (kCl) are determined using relative rate method, at 298 K. The values of kOH are (6.45 ± 1.69), (11.95 ± 2.79) and (11.38 ± 2.64) × 10-11 cm3 molecule-1 s-1 for 2,5-DHF, 2,3-DHF and 3,4-DHP, respectively and kO3 are (1.65 ± 0.31), (443.20 ± 79.0) and (31.36 ± 5.80) × 10-17 cm3 molecule-1 s-1 for 2,5-DHF, 2,3-DHF and 3,4-DHP, respectively. The value of kCl for 3,4-DHP is (6.15 ± 0.84) × 10-10 cm3 molecule-1 s-1. The dominant pathway of tropospheric degradation of 2,5-DHF is the reaction with OH, whereas that of 2,3-DHF is the reaction with O3. Reaction with both OH and O3 are equally important in the case of 3,4-DHP. Under the conditions of marine boundary layer, the reaction with Cl atom is important in the tropospheric degradation of 2,5-DHF and 3,4-DHP, but insignificant in the case of 2,3-DHF (only 1.8%). The estimated tropospheric lifetimes in the day-time are 2.0, 0.08 and 0.62 h for 2,5-DHF, 2,3-DHF and 3,4-DHP respectively. The presence of O atom, unsaturation, conjugation etc. influences the rate coefficients in a complex manner. However, there is a good correlation of kOH with HOMO energy, which further improves by treating the molecules separately, either as ethers and hydrocarbons, or as cyclic and acyclic molecules. The values of kO3 of these ethers fit very well with the straight line regression derived for simple alkenes with their HOMO energy, except 2,3-DHF, which has a high strain enthalpy. The values of kCl also show a similar trend of increase with HOMO energy, but the correlation is not as good as that of kOH.

  5. Study on the reaction of CH2 with H2 at high temperature.

    PubMed

    Lee, Pei-Fang; Matsui, Hiroyuki; Wang, Niann-Shiah

    2012-03-01

    Thermal decomposition of CH(2)I(2) [sequential C-I bond fission processes, CH(2)I(2) + Ar → CH(2)I + I + Ar (1a) and CH(2)I + Ar → (3)CH(2) + I + Ar (1b)], and the reactions of (3)CH(2) + H(2) → CH(3) + H (2) and (1)CH(2) + H(2) → CH(3) + H (3) have been studied by using atomic resonance absorption spectrometry (ARAS) of I and H atoms behind reflected shock waves. Highly diluted CH(2)I(2) (0.1-0.4 ppm) with/without excess H(2) (300 ppm) in Ar has been used so that the effect of the secondary reactions can be minimized. From the quantitative measurement of I atoms in the 0.1 ppm CH(2)I(2) + Ar mixture over 1550-2010 K, it is confirmed that two-step sequential C-I bond fission processes of CH(2)I(2), (1a) and (1b), dominate over other product channels. The decomposition step (1b) is confirmed to be the rate determining process to produce (3)CH(2) and the least-squares analysis of the measured rate gives, ln(k(1b)/cm(3) molecule(-1) s(-1)) = -(17.28 ± 0.79) - (30.17 ± 1.40) × 10(3)/T. By utilizing this result, we examine reactions 2 and 3 by monitoring evolution of H atoms in the 0.2-0.4 ppm CH(2)I(2) + 300 ppm H(2) mixtures over 1850-2040 K. By using a theoretical result on k(2) (Lu, K. W.; Matsui, H.; Huang, C.-L.; Raghunath, P.; Wang, N.-S.; Lin, M. C. J. Phys. Chem. A 2010, 114, 5493), we determine the rate for (3) as k(3)/cm(3) molecule(-1) s(-1) = (1.27 ± 0.36) × 10(-10). The upper limit of k(3) (k(3max)) is also evaluated by assuming k(2) = 0, i.e., k(3max)/cm(3) molecule(-1) s(-1) = (2.26 ± 0.59) × 10(-10). The present experimental results on k(3) and k(3max) is found to agree very well with the previous frequency modulation spectroscopy study (Friedrichs, G.; Wagner, H. G. Z. Phys. Chem. 2001, 215, 1601); i.e., the importance of the contribution of (1)CH(2) in the reaction of CH(2) with H(2) at elevated temperature range is reconfirmed.

  6. The study of helicon plasma source.

    PubMed

    Miao, Ting-Ting; Zhao, Hong-Wei; Liu, Zhan-Wen; Shang, Yong; Sun, Liang-Ting; Zhang, Xue-Zhen; Zhao, Huan-Yu

    2010-02-01

    Helicon plasma source is known as efficient generator of uniform and high density plasma. A helicon plasma source was developed for investigation of plasma neutralization and plasma lens in the Institute of Modern Physics in China. In this paper, the characteristics of helicon plasma have been studied by using Langmuir four-probe and a high argon plasma density up to 3.9x10(13) cm(-3) have been achieved with the Nagoya type III antenna at the conditions of the magnetic intensity of 200 G, working gas pressure of 2.8x10(-3) Pa, and rf power of 1200 W with a frequency of 27.12 MHz. In the experiment, the important phenomena have been found: for a given magnetic induction intensity, the plasma density became greater with the increase in rf power and tended to saturation, and the helicon mode appeared at the rf power between 200 and 400 W.

  7. Overview of the electric propulsion plasma diagnostics suite for the VASIMR VX-200 testbed

    NASA Astrophysics Data System (ADS)

    Olsen, Christopher; Longmier, Benjamin; Ballenger, Maxwell; Squire, Jared; Glover, Tim; Carter, Mark; Bering, Edgar; Giambusso, Matthew

    2012-10-01

    Descriptions of the various plasma diagnostics and data analysis methods are given for instruments used in high power (> 100 kW) electric propulsion testing. These include planar Langmuir probes, an articulating retarding potential analyzer, a double Langmuir probe, a multi-axis magnetometer, a high frequency electric field probe, microwave interferometer, and momentum flux targets. These diagnostics have been used to measure the efficiencies of the thruster, plasma source, ion cyclotron resonance booster, and magnetic nozzle as well as used to explore physical phenomena in the plume such as ion/electron detachment, plasma turbulence, and magnetic field line stretching. Typical plume parameters range up to 10^13 cm-3 electron density, 1 kG applied magnetic fields, ion energies in excess of 150 eV, and cold electrons (2 -- 5 eV) with a spatial measurement range over 2 m.

  8. Preliminary results of the trapped atom clock on a chip.

    PubMed

    Lacroute, Clement; Reinhard, Friedemann; Ramirez-Martinez, Fernando; Deutsch, Christian; Schneider, Tobias; Reichel, Jakob; Rosenbusch, Peter

    2010-01-01

    We present an atomic clock based on the interrogation of magnetically trapped (87)Rb atoms. Two photons, in the microwave and radiofrequency domain, excite the clock transition. At a magnetic field of 3.23 G the clock transition from |F = 1, m(F) = -1> to |F = 2, m(F) = 1> is 1st-order insensitive to magnetic field variations. Ramsey interrogation times longer than 2 s can be achieved, leading to a projected clock stability in the low 10(-13) at 1 s for a cloud of 10(5) atoms. We use an atom chip to cool and trap the atoms. A coplanar waveguide is integrated to the chip to carry the Ramsey interrogation signal, making the physics package as small as (5 cm)(3). We describe the experimental setup and show preliminary Ramsey fringes of line width 1.25 Hz.

  9. Incorporation of the Data Acquisition System with a Small Helicon Plasma Experiment (HPX)

    NASA Astrophysics Data System (ADS)

    Nolan, Stephen; James, R. W.; Page, E. L.; Zuniga, J.; Schlank, C.; Lopez, M.; Sherman, J.; Stutzman, B. S.

    2012-10-01

    At the Coast Guard Academy Plasma Lab (CGAPL), a small Helicon Plasma Experiment (HPX) is being developed to utilize the reputed high densities (10^13 cm-3 and higher) at low pressure (.01 T) [1], in high temperature and density diagnostic development for future laboratory investigations. With first plasmas at hand, HPX is constructing triple and mach particle probes, magnetic probes, and a single point Thompson Scattering system for HPX plasma property investigations. A 32-channel National Instruments Data Acquisition (DAQ) Board capable of sampling at 12 bits of precision at 2 MS/s and running multiple simultaneous experiments is currently under construction. This DAQ System with integrated storage and GUI's will gather and digitize plasma data from the associated diagnostics for further analysis. Progress on the current implementation of the DAQ system will be reported.

  10. Particle Probe Investigations on the Helicon Plasma Experiment (HPX)

    NASA Astrophysics Data System (ADS)

    Sherman, Justin; James, R. W.; Lopez, M.; Nolan, S.; Page, E. L.; Schlank, C.; Stutzman, B. S.; Zuniga, J.

    2012-10-01

    A small Helicon Plasma Experiment (HPX) has been constructed at the Coast Guard Academy Plasma Lab (CGAPL) to utilize the reputed high densities at low pressure (.01 T) [1], in high temperature and density diagnostic development for future laboratory investigations. With the initial construction phase complete, HPX has produced its first plasmas. Efforts to develop and enhance the high temperature and density (10^13 cm-3 and higher) helicon plasmas at low pressures (.01 T) reported by Toki, Shinohara, et. al. continue. Currently, particle probes to measure plasmas' temperatures and densities, necessary to discern the plasma mode transitions, are in development. Construction of independent mach and triple probes for single point surface investigations are underway and once installed, they will be followed by a triple probe array to produce a more comprehensive density and surface view. Progress on the construction and findings of these probes on HPX will be reported.

  11. Hyperfine polarization and its normal gradient coefficient of (87)Rb atoms in the vicinity (approximately 10(-5) cm) of coated and uncoated Pyrex glass surfaces.

    PubMed

    Zhao, K; Wu, Z

    2003-09-12

    We have made regionally specific measurement of the hyperfine polarization of 87Rb atoms in the vicinity ( approximately 10(-5) cm) of coated and uncoated Pyrex glass surfaces. We find that the polarization near an uncoated surface decreases rapidly with decreasing distance from the surface whereas for a silicone-coated surface the polarization is independent of the distance from the surface. We have also determined the normal gradient coefficient micro (S.I) of the hyperfine polarization in uncoated cells. In a representative uncoated cell, at a Rb density 7.35 x 10(13) cm(-3) and a pump beam intensity 1.3 W/cm(2), we find micro(S.I)=24+/-7 microm(-1).

  12. Multi-channel Doppler backscattering measurements in the C-2 field reversed configuration.

    PubMed

    Schmitz, L; Ruskov, E; Deng, B H; Gota, H; Gupta, D; Tuszewski, M; Douglass, J; Peebles, W A; Binderbauer, M; Tajima, T

    2014-11-01

    A versatile heterodyne Doppler Backscattering (DBS) system is used to measure density fluctuation levels (in the wavenumber range kρs ≤ 50), and the toroidal E × B flow velocity in the C-2 Field-Reversed Configuration (FRC). Six tunable frequencies in three waveguide bands (26 GHz ≤ f ≤ 90 GHz) are launched using monostatic beam optics, via a quasi-optical beam combiner/polarizer and an adjustable parabolic focusing mirror (inside the vacuum enclosure) achieving Gaussian beam spot sizes of 3-5.5 cm at the X/O-mode cutoff. The DBS system covers plasma densities of 0.8 × 10(13) ≤ ne ≤ 1 × 10(14) cm(-3), and provides access to the FRC core (up to the field null) and across the FRC separatrix into the scrape-off layer plasma.

  13. Thermally stimulated currents in layered Ga4SeS3 semiconductor

    NASA Astrophysics Data System (ADS)

    Aytekin, S.; Yuksek, N. S.; Goktepe, M.; Gasanly, N. M.; Aydinli, A.

    2004-10-01

    Thermally stimulated current (TSC) measurements are carried out on nominally undoped Ga4SeS3 layered semiconductor samples with the current flowing along the c-axis in the temperature range of 10 to 150 K. The results are analyzed according to various methods, such as curve fitting, initial rise and Chen's methods, which seem to be in good agreement with each other. Experimental evidence is found for the presence of three trapping centers in Ga4SeS3 with activation energies of 70, 210 and 357 meV. The calculation yielded 7.9 × 10-21, 7.0 × 10-19 and 1.5 × 10-13 cm2 for the capture cross section, and 1.6 × 1010, 6.5 × 1010 and 1.2 × 1011 cm-3 for the concentration of the traps studied.

  14. Crystal structure of (S)-2-[(3S,8S,9S,10R,13S,14S,17R)-3-hy-droxy-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetra-deca-hydro-1H-cyclo-penta[a]phenanthren-17-yl]-N-meth-oxy-N-methyl-pro-pan-amide (Fernholz Weinreb amide).

    PubMed

    Viktorsson, Elvar Ørn; Åstrand, Ove Alexander Høgmoen; Haseeb, Rasha Sabah; Görbitz, Carl Henrik; Rongved, Pål

    2015-03-01

    The literature compound 3β-hy-droxy-bis-nor-5-cholenic aldehyde is an important inter-mediate for the synthesis of new modulators of the nuclear oxysterol receptor Liver X. As part of our ongoing search for new LXR antagonists, the title compound, C24H39NO3, has proven to be an important inter-mediate in our new synthetic pathway, giving the corresponding aldehyde in high yield and in only three steps from the commercially available 3β-hy-droxy-bis-nor-5-cholenic acid. The title amide crystallized with two mol-ecules in the asymmetric unit, linked into helices by O-H⋯O hydrogen bonds involving the hy-droxy and carbonyl groups.

  15. Evaluated kinetics of terminal and non-terminal addition of hydrogen atoms to 1-alkenes: a shock tube study of H + 1-butene.

    PubMed

    Manion, Jeffrey A; Awan, Iftikhar A

    2015-01-22

    Single-pulse shock tube methods have been used to thermally generate hydrogen atoms and investigate the kinetics of their addition reactions with 1-butene at temperatures of 880 to 1120 K and pressures of 145 to 245 kPa. Rate parameters for the unimolecular decomposition of 1-butene are also reported. Addition of H atoms to the π bond of 1-butene results in displacement of either methyl or ethyl depending on whether addition occurs at the terminal or nonterminal position. Postshock monitoring of the initial alkene products has been used to determine the relative and absolute reaction rates. Absolute rate constants have been derived relative to the reference reaction of displacement of methyl from 1,3,5-trimethylbenzene (135TMB). With k(H + 135TMB → m-xylene + CH3) = 6.7 × 10(13) exp(-3255/T) cm(3) mol(-1) s(-1), we find the following: k(H + 1-butene → propene + CH3) = k10 = 3.93 × 10(13) exp(-1152 K/T) cm(3) mol(-1) s(-1), [880-1120 K; 145-245 kPa]; k(H + 1-butene → ethene + C2H5) = k11 = 3.44 × 10(13) exp(-1971 K/T) cm(3) mol(-1) s(-1), [971-1120 K; 145-245 kPa]; k10/k11 = 10((0.058±0.059)) exp [(818 ± 141) K/T), 971-1120 K. Uncertainties (2σ) in the absolute rate constants are about a factor of 1.5, while the relative rate constants should be accurate to within ±15%. The displacement rate constants are shown to be very close to the high pressure limiting rate constants for addition of H, and the present measurements are the first direct determination of the branching ratio for 1-olefins at high temperatures. At 1000 K, addition to the terminal site is favored over the nonterminal position by a factor of 2.59 ± 0.39, where the uncertainty is 2σ and includes possible systematic errors. Combining the present results with evaluated data from the literature pertaining to temperatures of <440 K leads us to recommend the following: k∞(H + 1-butene → 2-butyl) = 1.05 × 10(9)T(1.40) exp(-366/T) cm(3) mol(-1) s(-1), [220-2000 K]; k∞(H + 1-butene → 1

  16. Reaction kinetics of the CN radical with methyl bromide

    NASA Astrophysics Data System (ADS)

    Hodny, Michael; Hershberger, John F.

    2016-02-01

    The kinetics of the CN + CH3Br reaction were studied using transient infrared laser absorption spectroscopy to detect CN reactants and HCN products. This reaction has a rate constant of k = (2.20 ± 0.6) × 10-12 exp (453 ± 98/T) cm3 molecule-1 s-1 over the range 298-523 K. Hydrogen abstraction to produce HCN + CH2Br is only a minor reaction product, with a branching fraction of 0.12 ± 0.02. Other product channels, including BrCN + CH3, CH2CN + HBr, CH3CN + Br are likely. An upper limit of 0.01 was established for the HBr yield. These results are in qualitative agreement with recent ab initio calculations.

  17. Rate constants for the reactions of benzyl and methyl-substituted benzyl radicals with O 2 and NO

    NASA Astrophysics Data System (ADS)

    Ebata, Takayuki; Obi, Kin-ichi; Tanaka, Ikuzo

    1981-02-01

    Rate constants for reactions of benzyl, o-niethylbenzyl and p-meihylbenzyl radicals with O 2 and NO have been measured at room temperature. The radicals were generated by UV flash photolysis and the time decay measured by absorption at ≈ 300 nm. The rate constants are: benzyl (0.99 ± 0.07 and 9.5 ± 1.2), o-methylbenzyl (1.2 ± 0.07 and 8.6 ± 0.8) and p-mithyl-benzyl (1.1= 0.10 and 8.9 = 0.9) for O 2 and NO respectively in units of 10 -12 cm 3 molecule -1 s -1.

  18. Theoretical study on atmospheric reactions of fluoranthene and pyrene with N2O5/NO3/NO2

    NASA Astrophysics Data System (ADS)

    Wang, Youfeng; Yang, Bo; Shu, Jinian; Li, Nana; Zhang, Peng; Sun, Wanqi

    2015-08-01

    It is complex to assign the products obtained from the gas-phase reactions of PAHs with NO3/NO2 and N2O5. For this purpose, theoretical calculations are performed. Results show that 2-nitrofluoranthene and 2-nitropyrene are the dominant products for reactions of fluoranthene and pyrene with NO3/NO2, while 3-nitrofluoranthene and 1-nitropyrene are the major nitration products of N2O5. SN2 reaction mechanisms are elucidated and homolytic mechanisms are calculated for the first time. Rate constants for reactions of fluoranthene and pyrene with N2O5 are deduced for the first time, which are 2.50 × 10-27 and 2.16 × 10-24 cm3 molecule-1 s-1, respectively at 298 K.

  19. Computational study of the I2O5 + H2O = 2 HOIO2 gas-phase reaction

    NASA Astrophysics Data System (ADS)

    Khanniche, Sarah; Louis, Florent; Cantrel, Laurent; Černušák, Ivan

    2016-10-01

    This paper presents the mechanism and the kinetics of the I2O5 (g) + H2O (g) = 2 HOIO2 (g) reaction. The potential energy surface was explored with the B3LYP and MP2 methods with the aug-cc-pVTZ basis set. The rate constants were computed as a function of temperature (250-750 K) using transition state theory. At the CCSD(T)/CBS level, the rate constants were estimated to be: (k in cm3 molecule-1 s-1) kforward(T) = 3.61 × 10-22 × T2.05 exp (-32.3 (kJ mol-1)/RT) and kreverse (T) = 6.73 × 10-27 × T2.90 exp (-24.5 (kJ mol-1)/RT). Implications for atmospheric chemistry and nuclear safety issues are discussed.

  20. Template-free nanosized faujasite-type zeolites

    NASA Astrophysics Data System (ADS)

    Awala, Hussein; Gilson, Jean-Pierre; Retoux, Richard; Boullay, Philippe; Goupil, Jean-Michel; Valtchev, Valentin; Mintova, Svetlana

    2015-04-01

    Nanosized faujasite (FAU) crystals have great potential as catalysts or adsorbents to more efficiently process present and forthcoming synthetic and renewable feedstocks in oil refining, petrochemistry and fine chemistry. Here, we report the rational design of template-free nanosized FAU zeolites with exceptional properties, including extremely small crystallites (10-15 nm) with a narrow particle size distribution, high crystalline yields (above 80%), micropore volumes (0.30 cm3 g-1) comparable to their conventional counterparts (micrometre-sized crystals), Si/Al ratios adjustable between 1.1 and 2.1 (zeolites X or Y) and excellent thermal stability leading to superior catalytic performance in the dealkylation of a bulky molecule, 1,3,5-triisopropylbenzene, probing sites mostly located on the external surface of the nanosized crystals. Another important feature is their excellent colloidal stability, which facilitates a uniform dispersion on supports for applications in catalysis, sorption and thin-to-thick coatings.