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Dehydration of human organism is an issue in case of fitness activity and elderly people. We have designed the solution for noninvasive and continuous monitoring which is the way for determination of body dehydration. This system is based on measurements of relative humidity near skin to calculate water release through the skin, actual body weight, and measurements of potassium ions concentration in urea, which is a basic component of urine.

The aim of this work is to investigate sunflower plants response on stress induced by silver(I) ions. The sunflower plants were exposed to silver(I) ions (0, 0.1, 0.5, and 1 mM) for 96 h. Primarily we aimed our attention to observation of basic physiological parameters. We found that the treated plants embodied growth depression, coloured changes and lack root hairs. Using of autofluorescence of anatomical structures, such as lignified cell walls, it was possible to determine the changes of important shoot and root structures, mainly vascular bungles and development of secondary thickening. The differences in vascular bundles organisation, parenchymatic pith development in the root centre and the reduction of phloem part of vascular bundles were well observable. Moreover with increasing silver(I) ions concentration the vitality of rhizodermal cells declined; rhizodermal cells early necrosed and were replaced by the cells of exodermis. Further we employed laser induced breakdown spectroscopy for determination of spatial distribution of silver(I) ions in tissues of the treated plants. The Ag is accumulated mainly in near-root part of the sample. Moreover basic biochemical indicators of environmental stress were investigated. The total content of proteins expressively decreased with increasing silver(I) ions dose and the time of the treatment. As we compare the results obtained by protein analysis – the total protein contents in shoot as well as root parts – we can assume on the transport of the proteins from the roots to shoots. This phenomenon can be related with the cascade of processes connecting with photosynthesis. The second biochemical parameter, which we investigated, was urease activity. If we compared the activity in treated plants with control, we found out that presence of silver(I) ions markedly enhanced the activity of urease at all applied doses of this toxic metal. Finally we studied the effect of silver(I) ions on activity of urease in in vitro conditions.

Ellipticine (5,11-dimethyl-6H-pyrido[4,3-b]carbazole) is an alkaloid that has been isolated from plants of an Apocynaceae family. It is one of the simplest naturally occurring alkaloids with a planar structure. Over the past decades, ellipticine became a very promising antitumor agent. Interaction with DNA is one of the most studied ellipticine effects on cell division. This phenomenon is not clearly explained so far. In our experiments we studied interaction of ellipticine with single-stranded and double-stranded oligonucleotides by electrochemical methods on mercury electrode. Differential pulse voltammetry was applied for ellipticine (Elli) and CA peak detection. Square wave voltammetry was applied for G peak detection. The effect of the interaction time and ellipticine concentrations on interactions of ellipticine with single- and double-stranded oligonucleotides was tested too.

Glutathione (GSH) is the water-soluble tripeptide playing a crucial role in number of cellular reactions including detoxification of heavy metals. Glutathione can be found both in oxidized (GSSG) and reduced (GSH) state. The aim of this work was to utilize the electrochemical methods for determining of glutathiones and for investigating interaction of GSH and cadmium, zinc, copper and nickel ions or food supplement for animal nutrition. It clearly follows from the results obtained that GSH and GSSG can be distinguished by cyclic voltammetry whereas the height of their current response is proportional to their concentration. Moreover, we were concerned with studying of these interactions by cyclic voltammetry. The markedly changes of GSH signal were observed and discussed. The highest decrease of GSH reductive signal cause cadmium ions followed by zinc, nickel and copper ones. Moreover we observed that reductive GSH signal gradually decreased (about 9 %) with increasing concentration of the feedstuff additive used in our experiments. In the conclusion, cyclic voltammetry offers a tool for studying of interaction of thiols with different substances such as heavy metals and/or feedstuff additives.

Introduction. Although platinum based cytostatic drugs have been successfully used in the chemotherapy of cancer for more than 30 years, its biochemical mechanism of action is still unclear. The current accepted opinion about cisplatin mechanism of action is that the drug induces its cytotoxic properties through binding to the nuclear DNA and subsequent interference with normal transcription, and/or DNA replication mechanisms. Objective. The aim of this paper was to study of binding of platinum cytostatic to DNA structure using of platinum biosensor. Materials and methods. Preparation of DNA adduct with cisplatin. dsDNA was modified in the presence NaClO4 by cisplatin for in the dark of a thermostatic box. Purification of DNA adduct. The obtained DNA adduct was purified by ultrafiltration. Preparation of biosensor. Metallothionein modified surface of hanging mercury drop electrode was used as a platinum biosensor. The platinum and Pt-DNA adduct were detected by adsorptive transfer stripping (AdTS) differential pulse voltammetry (DPV). AdTS DPV parameters: time of accumulation 240 s, time of interaction 400 s. Results. Here we studied a binding of different platinum based cytostatics (cisplatin, carboplatin and oxaliplatin) to genome DNA. The influence of concentration of DNA, temperature and ionic strength on yield of adducts has been described. Consequently, we used the suggested heavy metal biosensor to detection of platinum modified DNA. We found out that the highest yield of Pt-DNA adducts has been obtained, if we used 100 mg/ml DNA at temperature 37 C for 24 h, because the yield of the modification was very low up to 10 h. In addition, increasing ionic strength negatively influenced yield of the modification. We were able to analyse tens of nanograms of Pt-DNA adduct per millilitre using the biosensor. Conclusions. The suggested approach shows the possible way for simple, sensitive, and rapid detection and determination of cisplatin and Pt-DNA adducts. In addition, the biosensor could be applied to study of binding of platinum to DNA structure.

Tumour markers are substances produced by malignant cells or by the organism as a response to cancer development. Determination of their levels can, therefore, be used to monitor the risk, presence and prognosis of a cancer disease or to monitor the therapeutic response or early detection of residual disease. Time-consuming imaging methods, examination of cerebrospinal fluid or tumour tissue and assays for hormones and tumour markers have been used for cancer diagnosis. However, no specific marker for diagnosis of childhood solid tumours has been discovered yet. In this study, metallothionein (MT) was evaluated as a prospective marker for such diseases. Serum metallothionein levels of patients with childhood solid tumours were determined using differential pulse voltammetry — Brdicka reaction. A more than 5-fold increase in the amount of metallothionein was found in sera of patients suffering from cancer disease, compared with those in sera of healthy donors. The average metallothionein level in the sera of healthy volunteers was 0.5 ± 0.2 μmol · dm –3 and was significantly different (p

Quality assurance is a major issue in the food industry. The authenticity of food ingredients and their traceability are required by consumers and authorities. Plant species such as barley (Hordeum vulgare), rice (Oryza sativa), sunflower (Helianthus annus), wheat (Triticum aestivum) and maize (Zea mays) are very common objects of interest of genetic modification (GMO); therefore the development of specific assays for their specific detection and quantification of GMO are needed. Furthermore, the production and trade of genetically modified lines from an increasing number of plant species brings about the need for control within research, environmental risk assessment, labelinglegal, and consumers’ information purposes. Electrochemical sensors and biosensors based on modification of working electrode could be suitable tools for these purposes. Here, we report using of an avidin-modified carbon paste electrode for rapid and sensitive determination of avidin in plant extract solution and in a transgenic maize extract. The process could be used to determine avidin concentrations up to 3pM in solution and 170nM in a maize seed extract. Moreover, we applied the method to analyze different maize flours.

This review provides a brief overview of the variety of carriers employed for targeted drug delivery used in cancer therapy and summarizes advantages and disadvantages of each approach. Particularly, the attention was paid to polymeric nanocarriers, liposomes, micelles, polyethylene glycol, poly(lactic-co-glycolic acid), dendrimers, gold and magnetic nanoparticles, quantum dots, silica nanoparti- cles, and carbon nanotubes. Further, this paper briefly focuses on several anticancer agents (paclitaxel, docetaxel, camptothecin, doxoru- bicin, daunorubicin, cisplatin, curcumin, and geldanamycin) and on the influence of their combination with nanoparticulate transporters to their properties such as cytotoxicity, short life time and/or solubility.

The mechanism of cisplatin effect has been well examined in in vitro models of malignant cell lines, but has never been studied on plant cell lines. When plant cell suspension culture of Nicotiana tabacum BY-2 was treated with cisplatin a decrease of viability with its increasing concentration was observed as well as the mitotic index. The structure of nuclei has also been changed in dependence on cisplatin concentration.

In the present paper, we report on the use of adsorptive transfer stripping technique in connection with chronopotentiometric stripping analysis for metallothionein determination and of differential pulse anodic stripping voltammetry for lead detection in tissues of wild perch (Perca fluviatilis, n = 6) from the Svratka River in Brno, Czech Republic. Primarily, we determined the content of MT in tissues (muscles, gonads, liver and spleen) of perch. We measured the highest content of MT in spleen and liver (100 to 350 ng MT per gram of fresh weight). We assume that the content of MT determined in perch tissues is probably related with the age of the fish and, therefore, with their exposition to heavy metals naturally occurring in the Svratka River. We detected a lead concentration in the tissues of one perch. It clearly follows from the results that the content of MT well correlates with the concentration of lead.

Several typical characteristics of prostate tissue have been identified including the ability to accumulate zinc(II). However, this feature of prostate cells is lost during carcinogenesis and, thus, prostate cells are unable to accumulate zinc(II) ions in high levels. Therefore, we can expect that zinc(II) ions can significantly contribute to the progression of tumour disease and to the ability of prostate cell lines to metastasize. In this study, we aimed our attention on determining the expression of Bcl-2, c-Fos, c-Jun, Ki-67, NF-κB and p53 genes in two prostate cell lines, as the 22Rv1 cell line, a model of aggressive partially androgen-sensitive prostate cancer and the PNT1A cell line, a normal prostate cell line model. Moreover, we were interested in the mechanisms through which exposure of these cell lines to zinc(II) ions could influence expression of the above-mentioned genes. We found that zinc(II) ions caused elevated expression of Ki-67, a marker of proliferation, extremely low expression of p53, high expression of Bcl-2 and no changes in the expression of p53. Our experimental data show different effect of zinc(II) ions on expression of the above-mentioned regulatory genes, which may give us more information on their impact on cancer development and progression with possible using for cancer therapy.

Biochemical markers suitable for monitoring of environmental pollution as well as for protecting of human health are searching. In this study, the effect of silver(I) ions on guppy fishes (Poecilia reticulata) was investigated. For this purpose, we employed hyphenated technique of high performance liquid chromatography coupled with multichannel CoulArray electrochemical detector. Content of cysteine in fishes treated with 0.5 and/or 1 mu g/l of silver(I) ions was 290 and/or 240 ng/g at the end of seven day long treatment. Reduced and oxidized glutathione were also determined. The enhance in GSSG content accompanied by decrease in GSH content confirms our hypothesis on increasing risk of oxidative stress in fishes due to treatment with silver(I) ions. In addition, we attempted to gain more information about health state of animals exposed to heavy metals from chromatograms measured by CoulArray detector. We counted areas of all signals detected up to 30 minutes in chromatograms of tissues from fishes treated with all concentrations of silver(I) ions. The content of thiols and thiols related compounds as a sum of signals areas enhanced with increasing concentration of silver(I) ions and time of exposition.

MicroRNAs (miRNAs) translationally repressing their target messenger RNAs due to their gene-regulatory functions play an important but not unexpected role in a tumour development. More surprising are the findings that levels of various miRNAs are well correlated with presence of specific tumours and formation of metastases. Moreover, these small regulatory molecules play a role in the resistance of cancer cells to commonly used anti-cancer drugs, such as cisplatin, anthracyclines, and taxanes. In that respect, miRNAs become very attractive target for potential therapeutic interventions. Improvements in the sensitivity of miRNAs detection techniques led to discovery of circulating miRNAs which became very attractive non-invasive biomarker of cancer with a substantial predictive value. In this review, the authors focus on i) oncogenic and anti-tumour acting miRNAs, ii) function of miRNAs in tumour progression, iii) possible role of miRNAs in resistance to anticancer drugs, and iv) diagnostic potential of miRNAs for identification of cancer from circulating miRNAs with special emphasis on prostate cancer. Moreover, relationship between miRNAs and expression of metallothionein is discussed as a possible explanation of resistance against platinum based drugs.

The cardiac glycosides are a group of compounds isolated from plants and some animals. They have been used in therapy for heart failure for many years. The cytotoxic effect of many cardiac glycosides has been demonstrated, but the mechanism of action is very complicated and complex, and Na+/K+-ATPase surely plays a crucial role in it. On the other hand, Na+/K+-ATPase is regulated by many endogenous factors, such as hormones or FXYD proteins, whose role in regulating the cell cycle has been studied intensively. This review focuses on the role of Na+/K+-ATPase in regulating the cell growth, the cell cycle and the cell proliferation and on the involvement of cardiac glycosides in regulating Na+/K+-ATPase. The cytotoxic effect of cardiac glycosides is discussed with respect to the apoptotic mechanisms possibly induced by these compounds. Novel strategies in cancer therapy based on cardiac glycosides are discussed as are possibilities for counteracting multidrug resistance by using cardiac glycosides. The aim of this review is to present cardiac glycosides not only as pharmaceuticals used in the management of heart failure, but also as potent cytotoxic agents with potential uses in cancer treatment.

Double pulse LIBS was utilized for mapping the nutrition elements and the accumulation of the heavy metals in a plant tissue slices. Elemental maps obtained by this technique were compared with images from fluorescence microscopy.