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Metalothioneiny jako biomarkery znečištění životního prostředí
Šestáková, Ivana; Křivská, D.; Navrátil, Tomáš
2021 - Czech
Sledování obsahu metalothioneinů jako biomarkeru znečištění vodního prostředí je\npředmětem řady studií i mezinárodního programu (Mediterranean Action Plan of The United\nNations Environment Program, 1999). Pro sledování vlivu kontaminace půdy jsou vhodnou\nmožností volně žijící drobní savci, kde hladiny metalothioneinů závisí na obsazích kovů\nv půdě, a i na dietních zvyklostech (omnivoři, herbivoři, karnivoři). V posledním desetiletí\nnabývají na významu studie vlivu parazitů, kde je popisován jak pozitivní, tak negativní vliv\nparazitů na obsahy kovů ve tkáních hostitele. U některých parazitů ryb byl zjištěn řádový nárůst\nobsahu kovů ve tkáních parazitu, který vedl k uvažování možnosti užití právě parazitů jako\nindikátoru znečištění. Small wild mammals living at contaminated soil are exploited for monitoring of their metal and\nmetallothionein (MT) levels, which can be influenced by presence of parasites. This has been\ntested in laboratory experiment with white rats (Rattus norvegicus) infected with tapeworm\nHimenolepis diminuta and given diet enriched with lead or zinc. The influence of parasite was\nconfirmed with analysis of samples, where metal concentrations in infected groups were\nlowered in comparison with the uninfected rats. Within infected groups, tapeworms MT levels\nwere 6 or 3 times higher than MT in tapeworms of the control group. Obtained results support\npossibility of using MT concentration in Himenolepis diminuta for biomonitoring.
Keywords:
metallothioneins; lead; zinc; rats
Available on request at various institutes of the ASCR
Metalothioneiny jako biomarkery znečištění životního prostředí
Sledování obsahu metalothioneinů jako biomarkeru znečištění vodního prostředí je\npředmětem řady studií i mezinárodního programu (Mediterranean Action Plan of The United\nNations Environment Program, ...
Voltametrické stanovení těžkých kovů ve včelím jedu za použití rtuťové kapkové elektrody a uhlíkového vodivého filamentu pro 3D tisk
Navrátil, Tomáš; Choińska-Mlynarczyk, Marta; Šestáková, Ivana; Hrdlička, Vojtěch
2021 - Czech
Včelí jed představuje sekret z jedového ústrojí včelích dělnic nebo včelí matky (nikoliv trubců).\nSmrtelná dávka pro člověka je asi 400-700 žihadel, LD50 myší i.v.=0,6 mg/kg. Po vysušení\nvzniká světle žlutý, velmi jemný prášek. Je rozpustný ve vodě za vzniku opaleskujícího roztoku.\nTypické složení (procenta představují podíl látky v sušině):\n -50-55 % silně bazický polypeptid melitin (poškozuje červené i bílé krvinky), 2-3 %\nappamin (vliv na nervovou soustavu), MCD (mast cell degranulating) peptid (narušuje\nčinnost buněčných membrán,\n Enzymy: 13-14 % fosfolypáza A a B, 2-3 % hyaluronidáza,\n Biogenní aminy: histamin, dopamin, noradrenalin.\nKromě výše uvedených látek jsou v jedu, podobně jako ve včelím medu, obsaženy látky, se\nkterými přichází tento blanokřídlý hmyz do styku během svého života. Jedná se tedy i o těžké\nkovy, kterými je kontaminováno naše životní prostředí. Analýza včelího jedu včel\nmedonosných žijících ve zvolené oblasti může tedy poskytnout informaci o plošném znečištění\npoměrně velké oblasti. Heavy metals belong to typical contaminants of our environment. It is known that they are\nmetabolized and incorporated into bee products as honey as well as honeybee venom (apitoxin).\nIt is supposed that their composition can reflect contamination of the “bee environment” and\ncan give us information about the environment in the neighborhood of human dwellings.\nThis study aimed to develop a simple method for the determination of heavy metals in honeybee\nvenom. Due to the complicated matrix, wet microwave mineralization with sulfuric acid, nitric\nacid, under increased temperature and pressure, and repeated boiling with concentrated nitric\nacid had to be applied. Voltammetry proved to be very suitable for the determination of heavy\nmetals.\nTwo types of working electrodes have been used: pen-type hanging mercury drop electrode and\ncarbon conductive filaments for 3D printers. Results achieved using both of them and their\nadvantages and limitations have been compared.
Keywords:
anodic stripping voltammetry; heavy metals; honeybee venom
Available on request at various institutes of the ASCR
Voltametrické stanovení těžkých kovů ve včelím jedu za použití rtuťové kapkové elektrody a uhlíkového vodivého filamentu pro 3D tisk
Včelí jed představuje sekret z jedového ústrojí včelích dělnic nebo včelí matky (nikoliv trubců).\nSmrtelná dávka pro člověka je asi 400-700 žihadel, LD50 myší i.v.=0,6 mg/kg. Po vysušení\nvzniká ...
Rozdíly v elektrochemické redukci jedno- a vícejaderných acylgermanů
Šimková, Ludmila; Dunlop, David; Liška, Alan; Ludvík, Jiří
2021 - Czech
Derivaty titanocenu nachazeji bohate vyuziti jako katalyzatory pri cele fade chemickych\ntransformaci. Nicmene v posledni dobe se zkouma i jejich potencialni vyuziti jako cytostatik\npri lecbe onkologickych onemocneni. Nedavne studie poukazaly na vyssi cytotoxicitu u cele\nfady titanocen difluoridovych derivatu v porovnani s jejich dichloridovymi analogy.\nNasledne zkoumani mechanismu ucinku titanocemi poukazalo na rozpad endoplasmatickeho\nretikula rakovinnych bunek pusobenim reaktivnich kyslikovych castic (ROS). Tyto castice\ngenerovane pomoci redoxne aktivnich kovu (v nasem pripade titanocenu) muzou byt ucinnym\nprostredkem pro selektivni likvidaci rakovinovych bunek, jejichz homeostaza je na pritomnost\nROS citlivejsi V porovnani se zdravymi bunkami. Recently, titanocene derivatives have been investigated in term of their potential use as\ncytostatics in the treatment of oncological diseases. The potentials for reduction or oxidation of\nindividual substances are one of the key properties which fundamentally affect the cytostatic\nefficiency. Our previous results led us to investigate the redox properties of series of titanocene\ndifluoride and dichloride derivatives. This study is mainly focused on the effect of the\nsubstitution of cyclopentadienyl ring and the halide anion on the redox properties of the\nderivative.
Keywords:
Titanocene derivatives; Tuning of redox behavior; Substitution of cyclopentadienyl ring
Available on request at various institutes of the ASCR
Rozdíly v elektrochemické redukci jedno- a vícejaderných acylgermanů
Derivaty titanocenu nachazeji bohate vyuziti jako katalyzatory pri cele fade chemickych\ntransformaci. Nicmene v posledni dobe se zkouma i jejich potencialni vyuziti jako cytostatik\npri lecbe ...
Preparation, Testing and Application of Amalgam Screen-Printed Electrodes
Josypčuk, Bohdan; Langmaier, Jan; Tvorynska, Sofiia
2021 - English
Silver amalgam screen-printed electrodes (AgA-SPEs) were designed, prepared, and tested for\nthe first time as perspective representatives among SPEs for measuring at high negative\npotentials. The precise coulometric preparation procedure for mercury deposition at the\nworking electrode surface of the commercial silver-SPE was developed. An optimal\nelectrolyzer construction for the mercury deposition, electrolyte composition, and electrolysis\nconditions were proposed. The maximum value of hydrogen overvoltage (-1979 ± 4 mV) was\nfound on AgA-SPE with 50% (w/w) of Hg content in 0.1 mol L-1 NaOH, which is more negative\nthan with the original silver-SPE for 387 mV (-1592 ± 12 mV).
Keywords:
electrochemistry; screen-printed electrodes; silver amalgam
Available on request at various institutes of the ASCR
Preparation, Testing and Application of Amalgam Screen-Printed Electrodes
Silver amalgam screen-printed electrodes (AgA-SPEs) were designed, prepared, and tested for\nthe first time as perspective representatives among SPEs for measuring at high negative\npotentials. The ...
Electrochemistry of Phospholes
Koláčná, Lucie; Liška, Alan; Ludvík, Jiří
2021 - English
Seventeen pentasubstituted phospholes with expected application in organic electronics were\nsynthesized and characterized electrochemically and by UV-vis spectra. Quantum chemical\ncalculations ofredox potentials and HOMO-LUMO energies were performed and experimental\nand theoretical data were successfully correlated. Tuning of redox properties can be achieved\nby combination of induction and resonance effects of substituents, extension / diminution of\nthe pi- delocalized system and by steric changes which affect intramolecular electron\ncommunication.
Keywords:
Pentasubstituted phospholes; Electrochemistry; UV-vis spectra
Available on request at various institutes of the ASCR
Electrochemistry of Phospholes
Seventeen pentasubstituted phospholes with expected application in organic electronics were\nsynthesized and characterized electrochemically and by UV-vis spectra. Quantum chemical\ncalculations ...
Electrochemical Characterization of Molecular Conductors Containing Redox Switching Element
Nováková Lachmanová, Štěpánka; Vavrek, František; Sebechlebská, Táňa; Šebera, Jakub; Kolivoška, Viliam; Lukášek, J.; Balzer, N.; Valášek, M.; Mayor, M.; Hromadová, Magdaléna
2021 - English
Electrochemical properties of new molecules containing tripodal anchor and redox switching\nelement have been studied by cyclic voltammetry and DFT quantum mechanical calculations.\nComparison of their redox properties with individual organometallic [Ru(terpy)2]2+t3+ and\n[Os(terpy)2]2+t3+ redox centers shows that covalently bonded tripodal anchor does not\ncompromise the reversibility of a redox process and has no effect on the stability of new\nmolecules. New molecular conductors have smaller HOMO-LUMO gap and both are oxidized\nat only slightly more positive potentials after tripodal substitution making them suitable for the\ndevelopment of molecular conductors with switching abilities.
Keywords:
Tripodal anchor; Cyclic voltammetry; DFT calculations
Available on request at various institutes of the ASCR
Electrochemical Characterization of Molecular Conductors Containing Redox Switching Element
Electrochemical properties of new molecules containing tripodal anchor and redox switching\nelement have been studied by cyclic voltammetry and DFT quantum mechanical calculations.\nComparison of ...
Electroplating of 3D Printed Electrodes for Selective Electrochemical Reduction of C02
Vaněčková, Eva; Bouša, Milan; Shestivska, Violetta; Kubišta, Jiří; Rathouský, Jiří; Sebechlebská, Táňa; Kolivoška, Viliam
2021 - English
In this work, computer assisted design and fused deposition modelling 3D printing are\nemployed to devise and manufacture electrodes from polylactic acid-carbon nanotube\nconductive composite. Electrodes are further modified by copper electroplating to prepare\ncatalysts for the electrochemical reduction of carbon dioxide. Scanning electron microscopy\nand energy dispersive X-ray analysis are used to inspect the surface morphology and chemical\ncomposition of obtained catalysts. Cyclovoltammetric investigations reveal that the copper\nelectroplating leads to the increase of electrode activity by three orders of magnitude.
Keywords:
3D printing; electrochemical reduction of carbon dioxide; electroplating
Available on request at various institutes of the ASCR
Electroplating of 3D Printed Electrodes for Selective Electrochemical Reduction of C02
In this work, computer assisted design and fused deposition modelling 3D printing are\nemployed to devise and manufacture electrodes from polylactic acid-carbon nanotube\nconductive composite. ...
Effect of elevated CO2 concentration and nitrogen nutrition on mais response to short-term high temperature and drought stress
Simor, J.; Klem, Karel
2021 - English
Within an experiment conducted in open top chambers in which two mais genotypes differing in stay-green trait were cultivated under elevated atmospheric CO2 concentration (EC) in comparison\nwith ambient CO2 concentration (AC), and in two contrast levels of nitrogen nutrition, the effect of acclimation to these factors on photosynthetic performance and water use efficiency, and subsequent response to short-term high temperature and drought stress was studied. Although EC improved water use efficiency, this effect did not alleviate the response to drought stress, and under some combinations of factors even led to a decrease in CO2 assimilation rate under drought stress. Differences in the stay- green trait between genotypes did not have a major effect on the response to high temperature and drought stress. Differences between genotypes were manifested mainly in the interaction with nitrogen nutrition, while in the Korynt genotype, non fertilised variants showed a lower response of CO2 assimilation rate to drought. Slight alleviating effect of higher nitrogen dose was found under EC conditions, while no nitrogen fertilisation rather increased drought resilience under AC conditions.
Keywords:
mais; elevated carbon dioxide; nitrogen nutrition; drought stress
Available at various institutes of the ASCR
Effect of elevated CO2 concentration and nitrogen nutrition on mais response to short-term high temperature and drought stress
Within an experiment conducted in open top chambers in which two mais genotypes differing in stay-green trait were cultivated under elevated atmospheric CO2 concentration (EC) in comparison\nwith ...
Zlepšování ekologického potenciálu a kvality vody v nádržích pomocí plovoucích vegetačních ostrovů.
Čtvrtlíková, Martina; Krolová, Monika; Kučerová, Andrea; Hejzlar, Josef; Hladík, M.; Kubečka, Jan
2021 - Czech
Cílem dvouletého pokusu bylo ověřit schopnost růstu čtyř druhů ostřic a rostlin z přirozeného náletu na bezsubstrátových plovoucích ostrovech. The aim of the two-year experiment was to verify the ability of four species of sedges and natural pioneering plants to grow on substrate-free floating islands.
Keywords:
floating vegetation islands; wetland plants; water quality
Available at various institutes of the ASCR
Zlepšování ekologického potenciálu a kvality vody v nádržích pomocí plovoucích vegetačních ostrovů.
Cílem dvouletého pokusu bylo ověřit schopnost růstu čtyř druhů ostřic a rostlin z přirozeného náletu na bezsubstrátových plovoucích ostrovech....
Enzymatic detoxification of cyanide using cyanide hydratases
Sedova, Anastasia; Rucká, Lenka; Glozlová, Michaela; Novotný, Petr; Martínková, Ludmila; Bojarová, Pavla
2021 - English
Cyanide, a strong chelator of metals in vital enzymes and proteins, is very toxic for most living organisms. Wastewaters from the mining, metallurgical and chemical industries contain significant concentrations of free cyanide. Though it can be largely eliminated by physicochemical methods, these processes may in turn lead to the formation of other waste. In addition, no effective methods have been found to neutralize cyanide spills coming from industrial accidents. The use of enzymes to remove cyanide is an attractive alternative, which is environmentally friendly and applicable to high cyanide concentrations. Cyanide hydratases (CynHs) are of considerable interest for the decomposition of hazardous cyanide wastes. Here we investigate the biochemical properties of new CynHs from Stereum hirsutum and Exidia glandulosa, it is of fundamental importance to preserve the enzyme activity at alkaline pH as cyanide waste is stored under these conditions.
Keywords:
free cyanide; cyanide hydratase; cyanide spills; cyanide waste
Available at various institutes of the ASCR
Enzymatic detoxification of cyanide using cyanide hydratases
Cyanide, a strong chelator of metals in vital enzymes and proteins, is very toxic for most living organisms. Wastewaters from the mining, metallurgical and chemical industries contain significant ...
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