23 research outputs found

    Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids

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    The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs). MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode

    An Adsorptive Transfer Technique Coupled with Brdicka Reaction to Reveal the Importance of Metallothionein in Chemotherapy with Platinum Based Cytostatics

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    The drugs based on platinum metals represent one of the oldest, but also one of the most effective groups of chemotherapeutic agents. Thanks to many clinical studies it is known that resistance of tumor cells to drugs is a frequent cause of chemotherapy failure. With regard to platinum based drugs, multidrug resistance can also be connected with increased expression of low-molecular weight protein metallothionein (MT). This study aimed at investigating the interactions of MT with cisplatin or carboplatin, using the adsorptive transfer technique coupled with differential pulse voltammetry Brdicka reaction (AdTS DPV Brdicka reaction), and a comparison of in vitro results with results obtained in vivo. The results obtained from the in vitro study show a strong affinity between platinum based drugs and MT. Further, we analyzed extracts of neuroblastoma cell lines treated with cisplatin or carboplatin. It is clear that neuroblastoma UKF-NB-4 cisplatin-resistant and cisplatin-sensitive cell lines unlikely respond to the presence of the platinum-based cytostatics cisplatin and carboplatin. Finally, we determined the level of MT in samples from rabbits treated with carboplatin and patients with retinoblastoma treated with the same drug

    Current Wildland Fire Patterns and Challenges in Europe : A Synthesis of National Perspectives

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    Changes in climate, land use, and land management impact the occurrence and severity of wildland fires in many parts of the world. This is particularly evident in Europe, where ongoing changes in land use have strongly modified fire patterns over the last decades. Although satellite data by the European Forest Fire Information System provide large-scale wildland fire statistics across European countries, there is still a crucial need to collect and summarize in-depth local analysis and understanding of the wildland fire condition and associated challenges across Europe. This article aims to provide a general overview of the current wildland fire patterns and challenges as perceived by national representatives, supplemented by national fire statistics (2009-2018) across Europe. For each of the 31 countries included, we present a perspective authored by scientists or practitioners from each respective country, representing a wide range of disciplines and cultural backgrounds. The authors were selected from members of the COST Action "Fire and the Earth System: Science & Society" funded by the European Commission with the aim to share knowledge and improve communication about wildland fire. Where relevant, a brief overview of key studies, particular wildland fire challenges a country is facing, and an overview of notable recent fire events are also presented. Key perceived challenges included (1) the lack of consistent and detailed records for wildland fire events, within and across countries, (2) an increase in wildland fires that pose a risk to properties and human life due to high population densities and sprawl into forested regions, and (3) the view that, irrespective of changes in management, climate change is likely to increase the frequency and impact of wildland fires in the coming decades. Addressing challenge (1) will not only be valuable in advancing national and pan-European wildland fire management strategies, but also in evaluating perceptions (2) and (3) against more robust quantitative evidence.Peer reviewe

    Carbon composite micro- and nano-tubes-based electrodes for detection of nucleic acids

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    Abstract The first aim of this study was to fabricate vertically aligned multiwalled carbon nanotubes (MWCNTs). MWCNTs were successfully prepared by using plasma enhanced chemical vapour deposition. Further, three carbon composite electrodes with different content of carbon particles with various shapes and sizes were prepared and tested on measuring of nucleic acids. The dependences of adenine peak height on the concentration of nucleic acid sample were measured. Carbon composite electrode prepared from a mixture of glassy and spherical carbon powder and MWCNTs had the highest sensitivity to nucleic acids. Other interesting result is the fact that we were able to distinguish signals for all bases using this electrode.</p

    Persistence, dispersal and genetic evolution of recently formed Spartina homoploid hybrids and allopolyploids in Southern England

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    International audienceIn Southampton Water, UK, the recent (c. 150 years ago) interspecific hybridisation between Spartina alterniflora (2n = 6x = 62; A-genome) and S. maritima (2n = 6x = 60; M-genome) gave rise to the homoploid hybrid (S. × townsendii, 2n = 6x = 62), and subsequently to the invasive allododecaploid species S. anglica (2n = 12x = 120–124) that has since spread worldwide. To address the question of dynamics of mixed ploidy populations involving these plants, we analysed several Spartina populations (fifty one individuals) in Southern England, UK, one of which was the presumed place of origin of the homoploid hybrid (Hythe). Using a combination of flow cytometry and ribosomal DNA (rDNA) genotyping we were able to identify the genomic composition and ploidy level of each individual analysed. The data show that the homoploid hybrid still dominates the population at Hythe (82 % of individuals collected in that locality) since its origin in the nineteenth century. We also identified S. × townsendii for the first time on Hayling Island (66 % individuals), indicating dispersal beyond its likely origin. The fertile allododecaploid S. anglica was mainly found in populations outside the initial hybridisation site, on Hayling Island and at Eling Marchwood. Quantification of the rDNA contributions from each parental genome showed that the ratios were mostly balanced in S. × townsendii. However, two (3 %) S. anglica individuals analysed have lost nearly all M-genome homeologs, indicating extensive repeat loss. Such variation indicates that despite the presumed single allopolyploid origin of S. anglica and genetic uniformity at other loci, it has undergone substantial changes at the rDNA loci following genome duplication. © 2016, Springer International Publishing Switzerland

    An Investigation of Glutathione-Platinum(II) Interactions by Means of the Flow Injection Analysis Using Glassy Carbon Electrode

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    Despite very intensive research in the synthesising of new cytostatics, cisplatin isstill one of the most commonly used anticancer drugs. Therefore, an investigation ofinteractions of cisplatin with different biologically important amino acids, peptides andproteins is very topical. In the present paper, we utilized flow injection analysis coupledwith electrochemical detection to study and characterize the behaviour of various forms ofglutathione (reduced glutathione – GSH, oxidized glutathione – GSSG and S-nitrosoglutathione – GSNO). The optimized conditions were as follows: mobile phase consistedof acetate buffer (pH 3) with a flow rate of 1 mL min-1. Based on results obtained we chose850 mV as the optimal potential for detection of GSH and 1,100 mV as the optimalpotential for detection of GSSG and GSNO. The detection limits of GSH, GSSG andGSNO were 100 pg mL-1, 50 ng mL-1 and 300 pg mL-1, respectively. Further, the optimized technique was used for investigation of interactions between cisplatin and GSH. We were able to observe the interaction between GSH and cisplatin via decrease in the signal corresponding to glutathione. Moreover, we evaluated the formation of the complex by spectrometry. The spectrometric results obtained were in good agreement with electrochemical ones

    Possibilities of electrochemical techniques in metallothionein and lead detection in fish tissues

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    Abstract In the present paper we employed adsorptive transfer stripping technique coupled with chronopotentiometric stripping analysis for determination of metallothionein (MT) in tumor cell lines and differential pulse voltammetry Brdicka reaction for determination of MT in blood serum of patients with head and neck cancer or retinoblastoma, and of rats treated with cisplatin with respect to discuss the role of MT in formation of resistance on treatment with heavy metal based cytostatics. The cisplatin or carboplatin sensitive and resistant neuroblastoma cell lines were derived from the maternal cell line isolated from the bone metastasis of patients with neuroblastoma. Based on the results obtained it can be concluded that level of MT increases with higher dose of platinum based cytostatics at cells. Further we focused on determination of MT in blood serum of rats treated with cisplatin (two doses 1.05 mg and/or 2.1 mg of cisplatin per kg). The highest level of MT at rats treated with 1.05 mg cisplatin was determined after four hours as 4.9 mmol/L. In the case of the second experimental group the maximum was reached even after two hours of the treatment as 4.8 mmol/L. In addition we were interested in the effect of cisplatin or carboplatin treatment of patients with a tumor disease. At patients with tumor in head and neck area treated with cisplatin we observed that the level of MT was going higher due to administration of the drug. This phenomenon was observed at all patients. However at patients with retinoblastoma treated with carboplatin we observed various phenomena including decreasing, increasing or no changes in MT level. Progression of MT levels was therefore individual and probably depended on tumor resistance to carboplatin

    Influence of Cadmium(II) Ions and Brewery Sludge on Metallothionein Level in Earthworms (Eisenia fetida) – Bio- transforming of Toxic Wastes

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    Metallothioneins belong to a group of intracellular, high molecular andcysteine-rich proteins whose content in an organism increase with increasing concentrationof a heavy metal. The aim of this work was to apply the electrochemical analysis for theanalysis of metallothioneins in earthworms exposed to cadmium ions and brewery sludge.Here we utilized adsorptive transfer technique coupled with differential pulse voltammetryBrdicka reaction to determine metallothionein in different biological samples. By meansthis very sensitive technique it was possible to analyze metallothionein in concentrationsbelow 1 μmol.l-1 with the standard deviation of 4-5%. We found out that the average MTlevel in the non-treated earthworms oscillated between 19 and 48 μmol.l-1. When weanalysed samples of earthworms treated by cadmium, we observed that the MT contentincreased with the exposition length and increase dose of cadmium ions. Finally, weattempted to study and compare the toxicity of the raw sludge and its leach by using ofearthworms. The raw brewery sludge caused the death of the earthworms quickly.Earthworms held in the presence of leach from brewery sludge increased their weight of147 % of their original weight because they ingested the nutrients from the sludge. Themetallothionein level changes markedly with increasing time of exposition and applieddose of toxic compound. It clearly follows from the obtained results that the MT synthesisis insufficient in the first hours of the exposition and increases after more than 24 h

    Influence of Cadmium(II) Ions and Brewery Sludge on Metallothionein Level in Earthworms (Eisenia fetida) – Bio- transforming of Toxic Wastes

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    Metallothioneins belong to a group of intracellular, high molecular andcysteine-rich proteins whose content in an organism increase with increasing concentrationof a heavy metal. The aim of this work was to apply the electrochemical analysis for theanalysis of metallothioneins in earthworms exposed to cadmium ions and brewery sludge.Here we utilized adsorptive transfer technique coupled with differential pulse voltammetryBrdicka reaction to determine metallothionein in different biological samples. By meansthis very sensitive technique it was possible to analyze metallothionein in concentrationsbelow 1 μmol.l-1 with the standard deviation of 4-5%. We found out that the average MTlevel in the non-treated earthworms oscillated between 19 and 48 μmol.l-1. When weanalysed samples of earthworms treated by cadmium, we observed that the MT contentincreased with the exposition length and increase dose of cadmium ions. Finally, weattempted to study and compare the toxicity of the raw sludge and its leach by using ofearthworms. The raw brewery sludge caused the death of the earthworms quickly.Earthworms held in the presence of leach from brewery sludge increased their weight of147 % of their original weight because they ingested the nutrients from the sludge. Themetallothionein level changes markedly with increasing time of exposition and applieddose of toxic compound. It clearly follows from the obtained results that the MT synthesisis insufficient in the first hours of the exposition and increases after more than 24 h
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