The Decomposition of Peroxynitrite to Nitroxyl Anion (NO ) and Singlet
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A Biochemical Rationale for the Discrete Behavior of Nitroxyl and Nitric Oxide in the Cardiovascular System
A biochemical rationale for the discrete behavior of nitroxyl and nitric oxide in the cardiovascular system Katrina M. Miranda*†‡, Nazareno Paolocci§, Tatsuo Katori§, Douglas D. Thomas*, Eleonora Ford¶, Michael D. Bartbergerʈ, Michael G. Espey*, David A. Kass§, Martin Feelisch**, Jon M. Fukuto¶, and David A. Wink*† *Radiation Biology Branch, Building 10, Room B3-B69, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892; §Division of Cardiology, Department of Medicine, The Johns Hopkins Medical Institutions, Baltimore, MD 21287; ¶Department of Molecular and Medical Pharmacology, Center for the Health Sciences, University of California, Los Angeles, CA 90095; ʈDepartment of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095; and **Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, LA 71130 Edited by Louis J. Ignarro, University of California School of Medicine, Los Angeles, CA, and approved May 20, 2003 (received for review February 20, 2003) The redox siblings nitroxyl (HNO) and nitric oxide (NO) have often cellular thiol functions (14, 15). Conversely, NO reacts only indi- been assumed to undergo casual redox reactions in biological sys- rectly with thiols after RNOS formation (17). tems. However, several recent studies have demonstrated distinct Contrasting effects are also apparent in vivo or ex vivo,for pharmacological effects for donors of these two species. Here, infu- example in models of ischemia reperfusion injury. Exposure to NO sion of the HNO donor Angeli’s salt into normal dogs resulted in donors at the onset of reperfusion provides protection against elevated plasma levels of calcitonin gene-related peptide, whereas reperfusion injury in the heart and other organs (18–20). -
The Effect of Calcium Carbonate and Sodium Bicarbonate on the Toxicity of Gossypol»
THE EFFECT OF CALCIUM CARBONATE AND SODIUM BICARBONATE ON THE TOXICITY OF GOSSYPOL» By WILLIS D. GALLUP, assistant chemist, and RUTH REDER, associate chemist, Department of Agricultural Chemistry Research, Oklahoma Agricultural Experi- ment Station INTRODUCTION In a previous study of the influence of certain dietary constituents on the response of rats to gossypol ingestion {2) ^ the authors showed that the toxicity of diets containing known amounts of gossypol was materially reduced when the diets were made basic by the addition of calcium carbonate and sodium bicarbonate. When the diets were made acidic by the addition of calcium chloride, only indirect evidence of a slight decrease in toxicity was obtained. Decreased toxicity was observed also when the protein content of the diet was increased from 13 percent to 35 percent. The conclusion was drawn that diets of high protein content and basic diets of high calcium content are favorable to the detoxication of gossypol. Considerable importance is attached to the results since calcium and protein are variable ingredients in diets used for the bio-assay of gossypol. The importance of these constituents in feeding cottonseed products to livestock has not been fully determined, although the value of supplementary protein in cottonseed-meal rations for pigs has recently been pointed out by Robison (5). In view of the favorable results obtained with sodium bicarbonate and calcium carbonate, it was deemed desirable to determine the pro- portion of these salts which would offer the greatest degree of pro- tection against gossypol injury and to determine the value of each salt in the presence of moderate amounts of thç other, as the principal elements of both are requisite for a normal nutritive condition. -
Oxygen Is Instrumental for Biological Signaling: an Overview
Review Oxygen Is Instrumental for Biological Signaling: An Overview John T. Hancock Department of Applied Sciences, University of the West of England, Bristol BS16 1QY, UK; [email protected]; Tel.: +44-(0)117-328-2475 Abstract: Control of cellular function is extremely complex, being reliant on a wide range of compo- nents. Several of these are small oxygen-based molecules. Although reactive compounds containing oxygen are usually harmful to cells when accumulated to relatively high concentrations, they are also instrumental in the control of the activity of a myriad of proteins, and control both the upregulation and downregulation of gene expression. The formation of one oxygen-based molecule, such as the superoxide anion, can lead to a cascade of downstream generation of others, such as hydrogen · peroxide (H2O2) and the hydroxyl radical ( OH), each with their own reactivity and effect. Nitrogen- based signaling molecules also contain oxygen, and include nitric oxide (NO) and peroxynitrite, both instrumental among the suite of cell signaling components. These molecules do not act alone, but form part of a complex interplay of reactions, including with several sulfur-based compounds, such as glutathione and hydrogen sulfide (H2S). Overaccumulation of oxygen-based reactive compounds may alter the redox status of the cell and lead to programmed cell death, in processes referred to as oxidative stress, or nitrosative stress (for nitrogen-based molecules). Here, an overview of the main oxygen-based molecules involved, and the ramifications of their production, is given. Keywords: carbon monoxide; hydrogen peroxide; hydroxyl radicals; hydrogen sulfide; NADPH oxidase; nitric oxide; peroxynitrite; redox; superoxide Citation: Hancock, J.T. -
Experimental Study on Capture of Carbon Dioxide and Production of Sodium Bicarbonate from Sodium Hydroxide
Environ. Eng. Res. 2016; 21(3): 297-303 pISSN 1226-1025 http://dx.doi.org/10.4491/eer.2016.042 eISSN 2005-968X Experimental study on capture of carbon dioxide and production of sodium bicarbonate from sodium hydroxide Jae-Goo Shim†, Dong Woog Lee, Ji Hyun Lee, No-Sang Kwak KEPCO Research Institute, 105 Munji-ro, Yuseong-gu, Daejeon, 54056, Korea ABSTRACT Global warming due to greenhouse gases is an issue of great concern today. Fossil fuel power plants, especially coal-fired thermal power plants, are a major source of carbon dioxide emission. In this work, carbon capture and utilization using sodium hydroxide was studied experimentally. Application for flue gas of a coal-fired power plant is considered. Carbon dioxide, reacting with an aqueous solution of sodium hydroxide, could be converted to sodium bicarbonate (NaHCO3). A bench-scale unit of a reactor system was designed for this experiment. The capture scale of the reactor system was 2 kg of carbon dioxide per day. The detailed operational condition could be determined. The purity of produced sodium bicarbonate was above 97% and the absorption rate of CO2 was above 95% through the experiment using this reactor system. The results obtained in this experiment contain useful information for the construction and operation of a commercial-scale plant. Through this experiment, the possibility of carbon capture for coal power plants using sodium hydroxide could be confirmed. Keywords: Carbon Capture, Carbon Utilization, Sodium Bicarbonate 1. Introduction the post-combustion amine process [8-11]. The amine process is has been a proven method for a relatively long time, and it is close to commercialization. -
Hidden Complexities in the Reaction of H2O2 and HNO Revealed by Ab Initio Quantum Chemical Cite This: Phys
PCCP PAPER Hidden complexities in the reaction of H2O2 and HNO revealed by ab initio quantum chemical Cite this: Phys. Chem. Chem. Phys., 2017, 19, 29549 investigations† Daniel Beckett, Marc Edelmann, Jonathan D. Raff and Krishnan Raghavachari* Nitroxyl (HNO) and hydrogen peroxide have both been implicated in a variety of reactions relevant to environmental and physiological processes and may contribute to a unique, unexplored, pathway for the production of nitrous acid (HONO) in soil. To investigate the potential for this reaction, we report an in-depth investigation of the reaction pathway of H2O2 and HNO forming HONO and water. We find the breaking of the peroxide bond and a coupled proton transfer in the first step leads to hydrogen nitryl (HNO2) and an endogenous water, with an extrapolated NEVPT2 (multireference perturbation theory) barrier of 29.3 kcal molÀ1. The first transition state is shown to possess diradical character linking the far peroxide oxygen to the bridging, reacting, peroxide oxygen. The energy of this first step, when calculated using hybrid density functional theory, is shown to depend heavily on the amount of Hartree–Fock exchange in the functional, with higher amounts leading to a higher barrier and more diradical character. Additionally, high amounts of spin contamination cause CCSD(T) to significantly overestimate the TS1 barrier with a value of 36.2 kcal molÀ1 when using the stable UHF wavefunction as the reference wavefunction. However, when using the restricted Hartree–Fock reference wavefunction, the TS1 CCSD(T) energy is lowered to yield a barrier of 31.2 kcal molÀ1, in much better agreement with the Received 29th August 2017, NEVPT2 result. -
Nitroaromatic Antibiotics As Nitrogen Oxide Sources
Review biomolecules Nitroaromatic Antibiotics as Nitrogen Oxide Sources Review Allison M. Rice, Yueming Long and S. Bruce King * Nitroaromatic Antibiotics as Nitrogen Oxide Sources Department of Chemistry and Biochemistry, Wake Forest University, Winston-Salem, NC 27101, USA; Allison M. Rice , Yueming [email protected] and S. Bruce (A.M.R.); King [email protected] * (Y.L.) * Correspondence: [email protected]; Tel.: +1-336-702-1954 Department of Chemistry and Biochemistry, Wake Forest University, Winston-Salem, NC 27101, USA; [email protected]: Nitroaromatic (A.M.R.); [email protected] antibiotics (Y.L.) show activity against anaerobic bacteria and parasites, finding * Correspondence: [email protected]; Tel.: +1-336-702-1954 use in the treatment of Heliobacter pylori infections, tuberculosis, trichomoniasis, human African trypanosomiasis, Chagas disease and leishmaniasis. Despite this activity and a clear need for the Abstract: Nitroaromatic antibiotics show activity against anaerobic bacteria and parasites, finding usedevelopment in the treatment of new of Heliobacter treatments pylori forinfections, these conditio tuberculosis,ns, the trichomoniasis, associated toxicity human Africanand lack of clear trypanosomiasis,mechanisms of action Chagas have disease limited and their leishmaniasis. therapeutic Despite development. this activity Nitroaro and a clearmatic need antibiotics for require thereductive development bioactivation of new treatments for activity for theseand this conditions, reductive the associatedmetabolism toxicity can convert -
Laboratory Manual
International Program UAM-Boston University Laboratory Manual Organic Chemistry I 2013-2014 Departamento de Química Orgánica Ernesto Brunet Romero Ana María Martín Castro Ramón Gómez Arrayás Laboratory Manual Table of Contents ............................................................................... 1 Introduction ............................................................................... 2 Prelab preparation ............................................................................... 2 Notebook ............................................................................. 3 Safety .............................................................................. 3 Laboratory Practices and Safety Rules ............................................................. 4 Accidents and injuries ........................................................................... 5 Fires ............................................................................. 5 Chemical Wastes ............................................................................. 6 Cleaning Responsibilities ............................................................................. 6 Lab cleanliness ............................................................................. 6 Laboratory Equipment ............................................................................. 7 Proper use of glassware ............................................................................. 8 Some techniques in lab experiments Heating, cooling and stirring ............................................................................ -
Quantification of Oxidative Stress Biomarkers: Development of a Method by Ultra Performance Liquid Chromatography MASTER DISSERTATION
DM Quantification of Oxidative Stress Biomarkers: Development of a Method by Ultra Performance Liquid Chromatography MASTER DISSERTATION Nome Autor do Liliana da Silva Rodrigues MASTER IN APPLIED BIOCHEMISTRY Quantification of Oxidative Stress Biomarkers: Development of a Method by Ultra Performance Liquid Chromatography Liliana da Silva Rodrigues July | 2016 Nome do Projecto/Relatório/Dissertação de Mestrado e/ou Tese de Doutoramento | Nome do Projecto/Relatório/Dissertação de Mestrado e/ou Tese DIMENSÕES: 45 X 29,7 cm NOTA* PAPEL: COUCHÊ MATE 350 GRAMAS Caso a lombada tenha um tamanho inferior a 2 cm de largura, o logótipo institucional da UMa terá de rodar 90º , para que não perca a sua legibilidade|identidade. IMPRESSÃO: 4 CORES (CMYK) ACABAMENTO: LAMINAÇÃO MATE Caso a lombada tenha menos de 1,5 cm até 0,7 cm de largura o laoyut da mesma passa a ser aquele que consta no lado direito da folha. Quantification of Oxidative Stress Biomarkers: Development of a Method by Ultra Performance Liquid Chromatography MASTER DISSERTATION Liliana da Silva Rodrigues MASTER IN APPLIED BIOCHEMISTRY ORIENTADORA Helena Caldeira Araújo CO-ORIENTADOR José de Sousa Câmara Quantification of oxidative stress biomarkers: Development of a Method by Ultra Performance Liquid Chromatography Dissertation submitted at the University of Madeira in order to obtain the degree of Master in Applied Biochemistry Liliana da Silva Rodrigues Work developed under the orientation of: Supervisor Prof. Doctor Helena Cardeira Araújo Co-supervisor Prof. Doctor José de Sousa Câmara Funchal, Portugal July 2016 To my Family “Sem eles nada disto seria possível” ***** Quantification of Oxidative Stress Biomarkers: Development of a Method by Ultra Performance Liquid Chromatography July 2016 Acknowledgment I would like to address an acknowledgement to all the people who collaborated in the accomplishment of this work. -
On the Distinction Between Nitroxyl and Nitric Oxide Using Nitronyl Nitroxides
Published on Web 05/26/2010 On the Distinction between Nitroxyl and Nitric Oxide Using Nitronyl Nitroxides Uri Samuni,† Yuval Samuni,‡ and Sara Goldstein*,§ Department of Chemistry and Biochemistry, Queens College, City UniVersity of New York, Flushing, New York 11367, and Department of Prosthodontics, School of Dental Medicine, and Institute of Chemistry, The Accelerator Laboratory, The Hebrew UniVersity of Jerusalem, Jerusalem 91904, Israel Received March 8, 2010; E-mail: [email protected] Abstract: A better understanding of the origins of NO and HNO and their activities and biological functions requires accurate methods for their detection and quantification. The unique reaction of NO with nitronyl nitroxides such as 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (C-PTIO), which yields the corresponding imino nitroxides, is widely used for NO detection (mainly by electron paramagnetic resonance spectroscopy) and for modulation of NO-induced physiological functions. The present study demonstrates that HNO readily reacts with nitronyl nitroxides, leading to the formation of the respective imino nitroxides and hydroxylamines via a complex mechanism. Through the use of the HNO donor Angeli’s salt (AS) with metmyoglobin as a competing agent, the rate constant for C-PTIO reduction by HNO has been determined to be (1.4 ( 0.2) × 105 M-1 s-1 at pH 7.0. This reaction yields the corresponding nitronyl • hydroxylamine C-PTIO-H and NO, which is trapped by C-PTIO to form NO2 and the corresponding imino • nitroxide, C-PTI. NO2 oxidizes the nitronyl and imino nitroxides to their respective oxoammonium cations, which decay mainly via comproportionation with the nitronyl and imino hydroxylamines. -
Malta Medicines List April 08
Defined Daily Doses Pharmacological Dispensing Active Ingredients Trade Name Dosage strength Dosage form ATC Code Comments (WHO) Classification Class Glucobay 50 50mg Alpha Glucosidase Inhibitor - Blood Acarbose Tablet 300mg A10BF01 PoM Glucose Lowering Glucobay 100 100mg Medicine Rantudil® Forte 60mg Capsule hard Anti-inflammatory and Acemetacine 0.12g anti rheumatic, non M01AB11 PoM steroidal Rantudil® Retard 90mg Slow release capsule Carbonic Anhydrase Inhibitor - Acetazolamide Diamox 250mg Tablet 750mg S01EC01 PoM Antiglaucoma Preparation Parasympatho- Powder and solvent for solution for mimetic - Acetylcholine Chloride Miovisin® 10mg/ml Refer to PIL S01EB09 PoM eye irrigation Antiglaucoma Preparation Acetylcysteine 200mg/ml Concentrate for solution for Acetylcysteine 200mg/ml Refer to PIL Antidote PoM Injection injection V03AB23 Zovirax™ Suspension 200mg/5ml Oral suspension Aciclovir Medovir 200 200mg Tablet Virucid 200 Zovirax® 200mg Dispersible film-coated tablets 4g Antiviral J05AB01 PoM Zovirax® 800mg Aciclovir Medovir 800 800mg Tablet Aciclovir Virucid 800 Virucid 400 400mg Tablet Aciclovir Merck 250mg Powder for solution for inj Immunovir® Zovirax® Cream PoM PoM Numark Cold Sore Cream 5% w/w (5g/100g)Cream Refer to PIL Antiviral D06BB03 Vitasorb Cold Sore OTC Cream Medovir PoM Neotigason® 10mg Acitretin Capsule 35mg Retinoid - Antipsoriatic D05BB02 PoM Neotigason® 25mg Acrivastine Benadryl® Allergy Relief 8mg Capsule 24mg Antihistamine R06AX18 OTC Carbomix 81.3%w/w Granules for oral suspension Antidiarrhoeal and Activated Charcoal -
Experimental Study on Capture of Carbon Dioxide and Production of Sodium Bicarbonate from Sodium Hydroxide
Environ. Eng. Res. 2016 Research Article http://dx.doi.org/10.4491/eer.2016.042 pISSN 1226-1025 eISSN 2005-968X In Press, Uncorrected Proof Experimental study on capture of carbon dioxide and production of sodium bicarbonate from sodium hydroxide † Jae-Goo Shim , Dong Woog Lee, Ji Hyun Lee, No-Sang Kwak KEPCO Research Institute, 105 Munji-ro, Yuseong-gu, Daejeon, 54056, Korea Abstract Global warming due to greenhouse gases is an issue of great concern today. Fossil fuel power plants, especially coal-fired thermal power plants, are a major source of carbon dioxide emission. In this work, carbon capture and utilization using sodium hydroxide was studied experimentally. Application for flue gas of a coal-fired power plant is considered. Carbon dioxide, reacting with an aqueous solution of sodium hydroxide, could be converted to sodium bicarbonate (NaHCO3). A bench-scale unit of a reactor system was designed for this experiment. The capture scale of the reactor system was 2 kg of carbon dioxide per day. The detailed operational condition could be determined. The purity of produced sodium bicarbonate was above 97% and the absorption rate of CO2 was above 95% through the experiment using this reactor system. The results obtained in this experiment contain useful information for the construction and operation of a commercial-scale plant. Through this experiment, the possibility of carbon capture for coal power plants using sodium hydroxide could be confirmed. This is an Open Access article distributed under the terms Received March 14, 2016 Accepted May 10, 2016 of the Creative Commons Attribution Non-Commercial Li- † cense (http://creativecommons.org/licenses/by-nc/3.0/) Corresponding Author which permits unrestricted non-commercial use, distribution, and repro- E-mail: [email protected] duction in any medium, provided the original work is properly cited. -
Nitroxyl-Mediated Peroxide Modification of Polypropylene
Nitroxyl-Mediated Peroxide Modification of Polypropylene by Benjamin Rhys Jones A thesis submitted to the Department of Chemical Engineering In conformity with the requirements for the degree of Master of Applied Science Queen’s University Kingston, Ontario, Canada (May 2021) Copyright ©Benjamin Rhys Jones, 2021 Abstract The thermal stability of alkoxyamine derivatives of polypropylene (PP) is examined through studies of model hydrocarbon systems and atactic-PP substrates. Primary, secondary and tertiary alkoxyamines are integral to modern techniques for modifying the architecture of linear PP materials, and detailed knowledge of their stability at polymer processing temperatures is needed to further understand the underlying principles of nitroxyl-based formulations. GC analysis of alkoxyamines derived from 2,4-dimethylpentane + TEMPO show that the tertiary regioisomer is susceptible to disproportionation to alkene + HOTEMPO at temperatures as low as 140 oC. Extension of these thermolysis experiments to atactic PP-g-HOTEMPO mirrored the model compound results, with appreciable extents of nitroxyl generation observed over a 20 min timescale at 180 oC. This reaction extent is not expected to dramatically alter the performance of nitroxyl-based formulations that modify the structure and composition of PP homopolymers. The yield of H-atom abstraction by peroxide-derived alkoxy radicals is another fundamental reaction that underlies polyolefin modifications. Indirect measures based on analysis of peroxide byproducts are supplemented with a fluorescence spectroscopy method that quantifies polymer- bound alkoxyamines. H-atom transfer from high density polyethylene (HDPE) and poly(ethylene-co-propylene) (EPR) was gained by using napthoyloxy-TEMPO, whose fluorophore supports a highly sensitive analytical method. This technique is extended to studies of reactive HDPE/EPR blending to ascertain the extent of peroxide migration from one phase to the other during the compounding process.