Sample Preparation for Fluorescence Microscopy: an Introduction Concepts and Tips for Better Fixed Sample Imaging Results
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Toxicological Profile for Formaldehyde
TOXICOLOGICAL PROFILE FOR FORMALDEHYDE U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES Public Health Service Agency for Toxic Substances and Disease Registry July 1999 FORMALDEHYDE ii DISCLAIMER The use of company or product name(s) is for identification only and does not imply endorsement by the Agency for Toxic Substances and Disease Registry. FORMALDEHYDE iii UPDATE STATEMENT Toxicological profiles are revised and republished as necessary, but no less than once every three years. For information regarding the update status of previously released profiles, contact ATSDR at: Agency for Toxic Substances and Disease Registry Division of Toxicology/Toxicology Information Branch 1600 Clifton Road NE, E-29 Atlanta, Georgia 30333 FORMALDEHYDE vii QUICK REFERENCE FOR HEALTH CARE PROVIDERS Toxicological Profiles are a unique compilation of toxicological information on a given hazardous substance. Each profile reflects a comprehensive and extensive evaluation, summary, and interpretation of available toxicologic and epidemiologic information on a substance. Health care providers treating patients potentially exposed to hazardous substances will find the following information helpful for fast answers to often-asked questions. Primary Chapters/Sections of Interest Chapter 1: Public Health Statement: The Public Health Statement can be a useful tool for educating patients about possible exposure to a hazardous substance. It explains a substance’s relevant toxicologic properties in a nontechnical, question-and-answer format, and it includes a review of the general health effects observed following exposure. Chapter 2: Health Effects: Specific health effects of a given hazardous compound are reported by route of exposure, by type of health effect (death, systemic, immunologic, reproductive), and by length of exposure (acute, intermediate, and chronic). -
A Guide to Proper Fixation of Tissue Specimens for Eventual Immunostaining (09/2015)
A Guide to Proper Fixation of Tissue Specimens for Eventual Immunostaining (09/2015) 1. First and most important - the original tissue sample must be of good quality. Factors such as warm ischemic time, the time delay between tissue excision and fixation, etc. are important. Ideally, tissues should be acquired as close to still being viable as possible, and put into fixative as soon as possible following excision. Delays lead to cell death, autolysis, and loss of tissue and cell integrity with concomitant losses of immunostaining (e.g. due to proteolysis of the antigen). If acquiring animal tissues, consider performing perfusion fixation prior to organ/tissue removal if it is an option. 2. Once the tissue sample is obtained, proper fixation technique is the next critical component of generating high quality fixed tissues that have the best chance to succeed in immumostaining. There are a number of important guidelines here: (a) Formalin solution slowly inactivates over time, thus fresh formalin should always be used. Freshly prepared buffered formaldehyde solution is the absolute best, but good results can certainly be obtained with commercial formalin solutions that are not too old. (b) Diffusion of formalin solution into the tissue is relatively slow- a rate of approximately 1 mm per hour. Thicker specimens take longer to fix, and such specimens fix in a gradient fashion - fixing fastest and most completely from the tissue surface towards the interior. The practical impact of this is that if a specimen is too thick, then the interior may not become fully fixed, or that significant autolysis can occur before the fixative diffuses into the area and finally does fix the interior. -
Bis(Chloromethyl) Ether
Bis(chloromethyl) Ether sc-210941 Material Safety Data Sheet Hazard Alert Code EXTREME HIGH MODERATE LOW Key: Section 1 - CHEMICAL PRODUCT AND COMPANY IDENTIFICATION PRODUCT NAME Bis(chloromethyl) Ether STATEMENT OF HAZARDOUS NATURE CONSIDERED A HAZARDOUS SUBSTANCE ACCORDING TO OSHA 29 CFR 1910.1200. NFPA FLAMMABILITY3 HEALTH4 HAZARD INSTABILITY1 SUPPLIER Company: Santa Cruz Biotechnology, Inc. Address: 2145 Delaware Ave Santa Cruz, CA 95060 Telephone: 800.457.3801 or 831.457.3800 Emergency Tel: CHEMWATCH: From within the US and Canada: 877-715-9305 Emergency Tel: From outside the US and Canada: +800 2436 2255 (1-800-CHEMCALL) or call +613 9573 3112 PRODUCT USE ■ The use of a quantity of material in an unventilated or confined space may result in increased exposure and an irritating atmosphere developing. Before starting consider control of exposure by mechanical ventilation. Formerly used for chloromethylations. As an intermediate in preparation of strongly-basic anion ion exchange resins of the quaternary ammonium type. Byproduct generated in production and use of chloromethyl methyl ether. CMME CARE: Small amounts form in mixtures of formaldehyde and hydrogen chloride HCl gas and also in formaldehyde solutions containing chloride ions. SYNONYMS C2-H4-C12-O, BCME, "bis(chloromethyl) ether", bis-CME, chloro(chloromethoxy)methane, "chloromethyl ether", dichlorodimethylaether, "sym-dichloro-dimethyl ether", "1, 1' -dichlorodimethyl ether", "1, 1' -dichlorodimethyl ether", "dichlorodimethyl ether, symmetrical", "sym-dichloromethyl ether", "dimethyl-1, 1' -dichloroether", "dimethyl-1, 1' -dichloroether", "methane-1, 1' dichloroether", oxybis(chloromethane) Section 2 - HAZARDS IDENTIFICATION CANADIAN WHMIS SYMBOLS EMERGENCY OVERVIEW RISK Harmful if swallowed. Toxic in contact with skin. Very toxic by inhalation. -
Formaldehyde Product-Type 02 (Disinfectants and Algaecides Not Intended for Direct Application to Humans Or Animals)
Regulation (EU) No 528/2012 concerning the making available on the market and use of biocidal products Evaluation of active substances Assessment Report Formaldehyde Product-type 02 (Disinfectants and algaecides not intended for direct application to humans or animals) October 2017 eCA: Germany Formaldehyde Product type 2 November 2017 CONTENTS 1. STATEMENT OF SUBJECT MATTER AND PURPOSE ............................................... 3 1.1. Procedure followed ................................................................................................................................ 3 1.2. Purpose of the assessment report .................................................................................................. 3 2. OVERALL SUMMARY AND CONCLUSIONS ................................................................... 3 2.1. Presentation of the Active Substance ........................................................................................... 3 2.1.1. Identity, Physico-Chemical Properties & Methods of Analysis ................................................... 3 2.1.2. Intended Uses and Efficacy ..................................................................................................................... 4 2.1.3. Classification and Labelling ..................................................................................................................... 5 2.2. Summary of the Risk Assessment ................................................................................................... 8 2.2.1. Human Health -
Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008
Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 William A. Rutala, Ph.D., M.P.H.1,2, David J. Weber, M.D., M.P.H.1,2, and the Healthcare Infection Control Practices Advisory Committee (HICPAC)3 1Hospital Epidemiology University of North Carolina Health Care System Chapel Hill, NC 27514 2Division of Infectious Diseases University of North Carolina School of Medicine Chapel Hill, NC 27599-7030 1 Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 3HICPAC Members Robert A. Weinstein, MD (Chair) Cook County Hospital Chicago, IL Jane D. Siegel, MD (Co-Chair) University of Texas Southwestern Medical Center Dallas, TX Michele L. Pearson, MD (Executive Secretary) Centers for Disease Control and Prevention Atlanta, GA Raymond Y.W. Chinn, MD Sharp Memorial Hospital San Diego, CA Alfred DeMaria, Jr, MD Massachusetts Department of Public Health Jamaica Plain, MA James T. Lee, MD, PhD University of Minnesota Minneapolis, MN William A. Rutala, PhD, MPH University of North Carolina Health Care System Chapel Hill, NC William E. Scheckler, MD University of Wisconsin Madison, WI Beth H. Stover, RN Kosair Children’s Hospital Louisville, KY Marjorie A. Underwood, RN, BSN CIC Mt. Diablo Medical Center Concord, CA This guideline discusses use of products by healthcare personnel in healthcare settings such as hospitals, ambulatory care and home care; the recommendations are not intended for consumer use of the products discussed. 2 -
Improved Spatial Resolution by Induced Live Cell and Organelle Swelling in Hypotonic Solutions Received: 9 April 2019 Astha Jaiswal1, Christian H
www.nature.com/scientificreports OPEN Improved spatial resolution by induced live cell and organelle swelling in hypotonic solutions Received: 9 April 2019 Astha Jaiswal1, Christian H. Hoerth1, Ana M. Zúñiga Pereira1,2 & Holger Lorenz1 Accepted: 23 August 2019 Induced morphology changes of cells and organelles are by far the easiest way to determine precise Published: xx xx xxxx protein sub-locations and organelle quantities in light microscopy. By using hypotonic solutions to swell mammalian cell organelles we demonstrate that precise membrane, lumen or matrix protein locations within the endoplasmic reticulum, Golgi and mitochondria can reliably be established. We also show the beneft of this approach for organelle quantifcations, especially for clumped or intertwined organelles like peroxisomes and mitochondria. Since cell and organelle swelling is reversible, it can be applied to live cells for successive high-resolution analyses. Our approach outperforms many existing imaging modalities with respect to resolution, ease-of-use and cost-efectiveness without excluding any co- utilization with existing optical (super)resolution techniques. Scientifc bioimaging aims to reveal scientifcally relevant information. Besides the mere metrics of biomaterial like cells, organelles, or even sub-organelle structures, more informative are data addressing protein sub-locations and interactions. Especially in the spatio-temporal context of cellular dynamics the precise protein sub-location within the membranous organelle system of the cell is crucial. To know that a certain protein is located within a particular organelle is ofen not sufcient. More precise information is needed, for example whether the protein is membrane-bound, or not. Tis puts a technical challenge on bioimaging since many organelles’ membrane assemblies are well below the micrometer range in size and distance. -
Aliphatic Halide-Carbonyl Condensations by Means of Sodium by Edgar A
U . S. Department of Commerce Research Paper RPl909 National Bureau of Standards Volume 41, August 1948 Part of the Journal of Research of the National Burea u of Standards Aliphatic Halide-Carbonyl Condensations by Means of Sodium By Edgar A. Cadwallader, Abraham Fookson, Thomas W. Mears, and Frank 1. Howard As a part of an in vestigation of the synthesis of highly branched ali phatic hydrocarbons that is being conducted at the National Bureau of Standa rds for the National Advisory Committee for Aeronautics, the l\'avy Bureau of Aeronautics, and t he Army Air Forces, se veral compounds have been prepared by interaction of alkyl halid es a nd various carbonyl compo unds in the presence of sod ium. This reaction makes possible the sy nthesis of ce rtain highly branched compound s not easily obtain able by other m eans. L Introduction cooling of the reaction mixture was effected by application of hot or cold oil baths. In some The usc of the GrignaI'd reaction for synthesis cases, particularly with low-boiling solvents, both of highly branched compounds is limited by un small necks of the flask were fitted with reflux I desirable side reactions, which become progres condensers with the elimination of the thermom . sively more pronounced as the degree of branching eter. of the reactan ts is increased. These side reactions Sodium sand was prepared batch-wise by heat involve the l'eclu ction and enolization of the adduct ing a weighed amount of sodium in a purified ligh t rather than the desired addition of the alkyl group. -
PERIODIC ACID SCHIFF (PAS) PROTOCOL PRINCIPLE: This Stain
PERIODIC ACID SCHIFF (PAS) PROTOCOL PRINCIPLE: This stain is used for the demonstration of glycogen. Tissue sections are first oxidized by periodic acid. The oxidative process results in the formation of aldehyde groupings through carbon-to-carbon bond cleavage. Free hydroxyl groups should be present for oxidation to take place. Oxidation is completed when it reaches the aldehyde stage. The aldehyde groups are detected by the Schiff reagent. A colorless, unstable dialdehyde compound is formed and then transformed to the colored final product by restoration of the quinoid chromophoric grouping. QUALITY ASSURANCE: The PAS stain with diastase or -amylase digestion has histochemical specificity for glycogen. Skeletal muscle normally contains glycogen and is often recommended as a positive control tissue. SPECIMEN REQUIRED: Snap frozen human striated muscle. (Use the isopentane freezing method previously described.) METHOD: Fixation: None, use snap frozen tissue. Technique: Cut 10 - 16 micron (12 µm) sections in cryostat from snap frozen biopsy. Attach one or more sections to a No.1_, 22 mm square coverslip. Equipment: Ceramic staining rack - Thomas Scientific #8542-E40 Columbia staining dish - Thomas Scientific #8542-C12 Columbia staining dish (jar) - Thomas Scientific #8542-E30 Forceps Latex gloves Reagents: • Absolute alcohol (100% ethanol) - Quantum, FLAMMABLE store at room temp. in a flammable cabinet • Glacial Acetic Acid -Fisher A507-500, CORROSIVE store at room temperature • Amylase - Sigma A-6505, store at room temperature • Chloroform - Baxter 049-4, FLAMMABLE CARCINOGEN store at room temperature in a flammable cabinet) • Periodic Acid - Sigma P7875, store at room temperature • Permount - Fisher SP15-100, FLAMMABLE HEALTH HAZARD • Reagent alcohol, ACS - histological Fisher A962-4 or HPLC A995, FLAMMABLE, TOXIC,TERATOGENIC, store at room temperature In flammable cabinet • Schiff Reagent - Harleco 6073/71, store at room temperature • Xylenes - Fisher #HC700-1GAL, FLAMMABLE, store room temperature in flammable cabinet) 1 Solutions: I. -
Adaptations at the Cell and Organelle Level for Utilizing Sunlight1-2
ADAPTATIONS AT THE CELL AND ORGANELLE LEVEL FOR UTILIZING SUNLIGHT1-2 W. H. CAMPBELL, P. ROBERTIE, R. H. BROWN3 AND C. C. BLACK Biochemistry Department, University of Georgia, Athens, Georgia 30602 ABSTRACT The discovery of multiple pathways of carbon dioxide assimilation and dissimilation in higher plants has drastically changed the research and thinking in plant biology. The theme is developed that adaptations within photosynthesis are of fundamental importance in plants and that changes in this dominant metabolic process arc apt to result in strong and immediate selection advantages in the course of plant evolution. Data are presented on the variations in photosynthetic CO2 assimilation in the reductive pentose phosphate cycle, the C4-dicarboxylic acid cycle, and in Crassulacean acid metabolism. Photo- synthetic studies with primitive plants such as P silo turn nudum indicate a metabolism similar to Cj-dicarboxylic acid may have arisen in this primitive plant. In order to establish a perspective on the metabolic processes in plants which might be subject to adaptation, we have considered the activities of major meta- bolic processes such as photosynthesis, photorespiration, dark respiration, transpira- tion, nitrogen fixation, ion uptake, and the synthesis of proteins, lipids, cell walls. Many of these metabolic activities are common to all of life forms and probably have been subject to common adaptations; for example, respiration or protein, lipid, and polysaccharide synthesis. Certain metabolic processes however, are unique to plants and to certain bacteria; among these are photosynthesis, photo- respiration, transpiration, nitrogen fixation, and ion uptake from soil. Unfor- tunately, quantitative data on these activities are not available on a comparable basis with a single plant or on a single plant organ, such as a leaf or a fruit. -
Fixation and Fixatives – Factors Influencing Chemical Fixation, Formaldehyde and Glutaraldehyde
Fixation and Fixatives – Factors influencing chemical fixation, formaldehyde and glutaraldehyde Author: Geoffrey Rolls edited by Hiram 3-25-18 This Fixation and Fixatives series covers the factors that influence the rate and effectiveness of tissue fixation as well as looking at two common fixatives: formaldehyde (histology) and glutaraldehyde (ultrastructural electron microscopy studies). Factors influencing chemical fixation There are a number of factors that will influence the rate and effectiveness of tissue fixation. Temperature: Increasing the temperature of fixation will increase the rate of diffusion of the fixative into the tissue and speed up the rate of chemical reaction between the fixative and tissue elements. It can also potentially increase the rate of tissue degeneration in unfixed areas of the specimen. For light microscopy initial fixation is usually carried out at room temperature and this may be followed by further fixation at temperatures up to 45°C during tissue processing. This is really a compromise that appears to be widely accepted to produce good quality morphological preservation. Microwave fixation may involve the use of higher temperatures, up to 65°C, but for relatively short periods. See Part 5 for further discussion. Time: The optimal time for fixation will vary between fixatives. For fixation to occur the fixative has to penetrate, by diffusion, to the centre of the specimen and then sufficient time has to be allowed for the reactions of fixation to occur. Both diffusion time and reaction time depend on the particular reagent used and the optimum time will vary from fixative to fixative. In busy diagnostic laboratories there is considerable pressure to reduce turnaround time and this can result in incompletely-fixed tissues being processed. -
Mechanistic Study for the Formation of Polyoxymethylene Dimethyl Ethers Promoted by Sulfonic Acid-Functionalized Ionic Liquids
Journal of Molecular Catalysis A: Chemical 408 (2015) 228–236 Contents lists available at ScienceDirect Journal of Molecular Catalysis A: Chemical journal homepage: www.elsevier.com/locate/molcata Mechanistic study for the formation of polyoxymethylene dimethyl ethers promoted by sulfonic acid-functionalized ionic liquids Fang Wang, Gangli Zhu, Zhen Li, Feng Zhao, Chungu Xia ∗, Jing Chen State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou 730000, PR China article info abstract Article history: Polyoxymethylene dimethyl ethers (DMMn), which are ideal additives for diesel fuel, are mainly syn- Received 5 February 2015 thesized from the condensation of methanol (MeOH) or dimethoxymethane (DMM) with 1,3,5-trioxane Received in revised form 14 July 2015 (TOX) or paraformaldehyde (PF) promoted by different acid catalysts. However, up to date, few studies Accepted 24 July 2015 have been reported to examine the formation mechanism of DMMn which is essential in understand- Available online 31 July 2015 ing the reaction and valuable in designing improved catalysts. In this work, using the density functional theory (DFT) calculations combined with experiment studies, we evaluate the formation mechanism of Keywords: DMMn which is promoted by sulfonic acid-functionalized ionic liquids (SO H-FILs). Our calculated results Polyoxymethylene dimethyl ethers 3 Sulfonic acid-functionalized ionic liquids indicate TOX and PF should dissociate into formaldehyde monomers firstly and then to react with MeOH Mechanism or DMM. However, their decomposition process is different where the dissociation of TOX proceeds along DFT a two-step mechanism while it follows a one-step mechanism for PF dissociation. -
Pesticides EPA 739-R-08-004 Environmental Protection and Toxic Substances June 2008 Agency (7510P)
US Environmental Protection Agency Office of Pesticide Programs Reregistration Eligibility Decision for Formaldehyde and Paraformaldehyde June 2008 United States Prevention, Pesticides EPA 739-R-08-004 Environmental Protection and Toxic Substances June 2008 Agency (7510P) Reregistration Eligibility Decision for Formaldehyde and Paraformaldehyde (Case 0556) UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460 OFFICE OF PREVENTION, PESTICIDES AND TOXIC SUBSTANCES CERTIFIED MAIL Dear Registrant: This is to inform you that the Environmental Protection Agency (hereafter referred to as EPA or the Agency) has completed its review of the available data and public comments received related to the preliminary risk assessments for the antimicrobial formaldehyde and paraformaldehyde. The enclosed Reregistration Eligibility Decision (RED) document was approved on June 30, 2008. Based on its review, EPA is now publishing its Reregistration Eligibility Decision (RED) and risk management decision for formaldehyde and paraformaldehyde and their associated human health and environmental risks. A Notice of Availability will be published in the Federal Register announcing the publication of the RED. The RED and supporting risk assessments for formaldehyde and paraformaldehyde are available to the public on EPA’s Pesticide Docket at: www.regulations.gov. The docket number is EPA-HQ-OPP-2008-0121. The formaldehyde and paraformaldehyde RED was developed through EPA’s public participation process, published in the Federal Register on September 10, 2004, which provides opportunities for public involvement in the Agency’s pesticide tolerance reassessment and reregistration programs. Developed in partnership with USDA and with input from EPA’s advisory committees and others, the public participation process encourages robust public involvement starting early and continuing throughout the pesticide risk assessment and risk mitigation decision making process.