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Methanol Outbreak in the Czech Republic in the year 2012 – Almost Two Years Later
Navrátil, Tomáš ; Zakharov, S. ; Pelclová, D. ; Mrázová, K.
Almost two years ago, in autumn 2012, a large methanol outbreak was registered in the Czech Republic (CR). The first case was registered in September 2012 in Moravian city Havířov. The source was connected with illegal production and sale of adulterated spirits. About 50 dead and more than 150 cases of methanol intoxications have been reported since September 2012. Some cases of intoxications, connected with old methanol sources distributed in 2012, have been registered up to now. Not all of total amount of prepared methanolic drinks has been found and hundreds liters of toxic methanol have remained in stores or in households. n the other hand, many people intoxicated during this outbreak and classified as “fully recovered” by their hospital discharge, have suffered by sequels of their intoxication at present (visual and nervous system disturbances) and their number has been increasing.
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Electrochemical Biosensors Based on Enzymatic Reactor with Amalgam Powder
Josypčuk, Bohdan ; Barek, J. ; Josypčuk, Oksana
Enzymatic reactor based on the powder of silver solid amalgam was suggested as the main part of biosensors in flow systems for the first time. 4-aminothiophenol, glutaraldehyde and enzyme were gradually bonded to the amalgam surface. Large surface of the fine amalgam particles maintains a big quantity of enzyme molecules. Biosensors were tested with enzymes ascorbate oxidase, glucose oxidase, catalase, tyrosinase and laccase. Electrochemical detection of the oxygen concentration change (for the first 3 enzymes) or the quinones concentration (tyrosinase and laccase) in the measured solution was done amperometrically by means of the tubular detector of silver solid amalgam. The current response of each biosensor was optimized with respect to the detection potential, the flow rate of the mobile phase, the injection volume and the enzymatic reactor volume. Under the found optimum conditions, concentration dependence and some statistical parameters of repeated measurements (relative standard deviation (RSD) for the studied enzymes was in the range 0.81 – 2.1 %) were measured. Biosensor with the ascorbate oxidase reactor was used for determination of ascorbic acid in the vitamin tablet Celaskon®. Results of the analysis were in good agreement with the contents of ascorbic acid declared by manufacturer and the RSD of these analyses was 2.0 %.
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Characterization of Liposomes Used as Model System of Biological Membranes by Glassy Carbon Electrode
Parisová, Martina ; Navrátil, Tomáš ; Šestáková, Ivana ; Barek, J.
This contribution deals with study and characterization of liposomes. These vesicles may serve as model membranes used for study of transporting processes of heavy metal ions across the real phospholipid membranes (PLMs). 1,2-dioleoyl-sn-glycero-3-phosphocholine was used for the formation of large unilamellar vesicles (LUV). These vesicles were prepared by hydration method. Interactions of cadmium ions with LUV in solution have been characterized using voltammetry, where glassy carbon electrode was used as the working electrode. Size and presence of liposomes in sample was proved by dynamic light scattering and free cadmium ions in samples were determined by differential pulse voltammetry.
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Short Information on Methanol Outbreak in the Czech Republic in the year 2012
Navrátil, Tomáš ; Zakharov, S. ; Pelclová, D. ; Mrázová, K.
This contribution reports briefly on the large methanol outbreak in the Czech Republic (CR) in autumn 2012. The first case was registered in September 2012 in Havířov. The source was unknown at that time, but it was connected with the illegal production and sale of adulterated spirits. More than 130 cases of methanol intoxication have been reported during September 2012 – April 2013. 44 people died, about 1/5 of intoxicated patients have suffered by sequels of intoxication and their number have been increasing. Moreover, the samples of methanol can be found in some illegal stores and in some households up to now.
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Voltametrické chování folátů a látek souvisejících s využitím stříbrné pevné amalgámové elektrody
Bandžuchová, L. ; Šelešovská, R. ; Navrátil, Tomáš ; Chýlková, J.
Foláty jsou biologicky aktivní látky odvozené od kyseliny listové (FA). Jejich strukturním základem je 6-methylpterin navázaný přes 4-aminobenzoovou kyselinu na několik zbytků glutamové kyseliny γ-peptidovou vazbou. FA patří do skupiny ve vodě rozpustných vitamínů B (B9). Struktura nejjednodušší formy kyseliny listové je uvedena na Obr. 1. Nejčastěji obsahuje 2-7 zbytků kyseliny glutamové. FA, resp. foláty jsou v organismu enzymaticky transformovány na tetrahydrofoláty (THF), které patří mezi přenašeče jednouhlíkových (C1) zbytků. THF jsou schopny přenášet uhlík v různých oxidačních stupních a proto jsou na rozdíl od jiných přenašečů považovány za univerzální 1. FA a foláty hrají klíčovou roli v metabolismu aminokyselin, při syntéze nukleových kyselin (NK), při dělení a syntéze buněk a při tvorbě červených krvinek. Hlavním projevem nedostatku FA je megaloblastická anémie, při které je narušena produkce červených krvinek a objevuje se nadbytek megaloblastů 2.
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