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References Chen, J. & Yiacoumi, S. (1997). Biosorption of Metal Ions from Aqueous Solutions. Sep. Sci. Technol. , 32, 51 - 69. Chen, J., Tendeyong, F. & Yiacoumi, S. (1997). Equilibrium and Kinetic Studies of Copper Ion Uptake by Calcium Alginate. Environ. Sci. Technol. 31, 1433 - 1439. Esposito, A., Paganelli, F. & Veglio, F. (2002). pH-related Equilibria Models for Biosorption in Single Metal Systems. Chem. Eng. Sci. 57, 307 - 313. Ibanez, J. P. & Umetsu, Y. (1999). Uptake of Copper from Extremely Dilute Solutions by Alginate Sorbent Material: an

.L., Packer L. 1968. Photoperoxidation in isolated chloroplast. I. Kinetics and stechiometry of fatty acid peroxidation. Arch. Biochemistry & Biophysic 125: 189-198. Janas K.M., Amarowicz R., Zielińska-Tomaszewska J., Kosińska A., Posmyk M. 2009. Induction of phenolic compounds in two dark-grown lentil cultivars with different tolerance to copper ions. Acta Physiol. Plant. 31: 587-595. Ke W., Xiong Z., Xie M., Luo Q. 2007. Accumulation, subcellular location and ecophysiological responses to copper stress in two Daucus carota L. populations. Plant Soil 292: 291-304. Konno

Abstract

The binary and ternary complex formations of poly(methyl vinyl ether-co-maleic anhydride) (PMVEMA) with copper ions and with bovine serum albumin (BSA) in the presence of copper ions in phosphate buffer solution at pH = 7 were examined by the techniques of UV-visible, fluorescence, dynamic light scattering, atomic force microscopy measurements. In the formation of binary complexes of PMVEMA-Cu(II), the addition of copper ions to the solution of PMVEMA in phosphate buffer solution at pH = 7 forms homogeneous solutions when the molar ratio of Cu(II)/MVEMA is 0.5. Then the formations of ternary complexes of PMVEMA-Cu(II)-BSA were examined. Study analysis revealed that the toxicities of polymer-metal and polymer-metal-protein mixture solutions depend on the nature and ratio of components in mixtures.

Abstract

In the present paper, the interaction between copper ions and proteins is presented, in order to elaborate a simple and rapid spectrophotometric assay of casein in milk. Under alkaline conditions, copper ions form the biuret complex with the proteins, which can be used in protein determination. Although very specific, the biuret method is less sensitive. Using insoluble copper phosphate, casein is able to extract copper ions, with which it forms the biuret complex, while either the complex or copper ions could be determined in the ultraviolet range. Indeed, an increased absorbance of biuret complex at 215 nm was found. Nevertheless, copper ions can be determined in UV as well, their concentration being proportional to that of casein. When used tetraglycine instead casein, mass spectrometric measurements at pH higher than 11 revealed the formation of complexes with many copper ions bound to each peptide bond-containing molecule. Nevertheless, on diluting the biuret solution the complex may dissociate leading to very complex UV spectra that should be further studied.

detergents on the development of chitons, Author's abstract, Vladivostok. (in Russian) 25. Yaroslavtseva L. M. and Sergeeva E. P., 2005 – Influence of copper ions on the early stages of development of the Pacific mussel Mytilus trossulus, Institute of Marine Biology, Far East Branch, Russian Academy of Sciences, Marine Biology , 31, 4, 267-273. (in Russian) 26. Zaitsev Y. P., Aleksandrov B. G. and Minicheva G. G., 2006 – North-Western part of the Black Sea: biology and ecology, Naukova Dumka, 701s. (in Russian)

Abstract

Normal oxygen metabolism is an endogenous source of reactive oxygen species (ROS). The source of ROS are also many environmental factors including heavy metals. In certain concentration range, the presence of ROS is necessary to maintain proper cell function. Thus, cells have many mechanisms, which role is focused on maintaining a constant concentration of ROS. Imbalance between the formation of ROS and action of a protective antioxidant system leads to oxidative stress. This may results with a damage to the structure of proteins, lipids and nucleic acids, which in turn can lead to disturbances in the functioning of the cell and even to the death. The aim of the study was to evaluate the effect of copper ions on the metabolic activity of garden cress Lepidium sativum L. The action of copper ions with different concentrations was treated seeds. After four, six and eight days after planting in the leaves of garden cress were determined the specific activity of guaiacol peroxidase (GPOX), lipid peroxidation and protein content. Additionally intake of copper ions was determined using adsorption spectrometry technique. The results revealed that the applied doses of copper ions affected the activity of guaiacol peroxidase. The highest enzyme activity was found in plant material, which was treated with dose of copper ions 1000 mg/dm3 regardless of day. In the same samples the lowest level of lipid peroxidation was found. The highest concentrations of total proteins was found in samples treated with the highest dose of copper ions. The copper content in the tested plant material is correlated with the applied dose of copper ions. Our results indicate reliable correlations between copper content and values of oxidative stress biomarkers in plant tissues.

.S. Saiwan and R. Naidu (eds), CRC Press, Taylor and Francis Group, Boca Raton, pp. 291-324. Sugijanto K., Indrayanto G., Cholies Z.M., 2002. The uptake of copper ions by cell suspension cultures of Agave amaniensis, and its effect on the growth, amino and hecogenin content. Plant Cell Tissue Organ Cult. 68: 287-292. Vasudevan A., Selvaraj N., Ganapa thi A., Kasthurirengan S., Ramesh Anbazhagan V., Manickava sagam M., Choi C.W., 2008. Leucine and spermidine enhance shoot differentiation in cucumber (Cucumis sativus L.). In Vitro Cell Dev. Biol. Plant 44: 300-306. Zacchini

SUMMARY

New emerging approaches in tissue engineering include incorporation of metal ions involved in various metabolic processes, such as Cu, Zn, Si into bioceramic scaffolds for enhanced cell growth and differentiation of specific cell types. The aim of the present work was to investigate the attachment, morphology, growth and mineralized tissue formation potential of Dental Pulp Stem Cells (DPSCs) seeded into Mg-based glassceramic scaffolds with incorporated Zn and Cu ions. Bioceramic scaffolds containing Si 60%, Ca 30%, Mg 7.5% and either Zn or Cu 2.5%, sintered at different temperatures were synthesized by the foam replica technique and seeded with DPSCs for up to 21 days. Scanning Electron Microscopy with associated Energy Dispersive Spectroscopy (SEM-EDS) was used to evaluate their ability to support the DPSCs’s attachment and proliferation, while the structure of the seeded scaffolds was investigated by X-Ray Diffraction Analysis (XRD). Zn-doped bioceramic scaffolds promoted the attachment and growth of human DPSCs, while identically fabricated scaffolds doped with Cu showed a cytotoxic behaviour, irrespective of the sintering temperature. A mineralized tissue with apatite-like structure was formed on both Cu-doped scaffolds and only on those Zn-doped scaffolds heat-treated at lower temperatures. Sol-gel derived Zn-doped scaffolds sintered at 890oC support DPSC growth and apatite-like tissue formation, which renders them as promising candidates towards dental tissue regeneration.

Introduction The prion protein (PrP) is known for its involvement in regenerative processes including adhesion, proliferation, differentiation and angiogenesis ( 1 ); in addition, it is mostly known for its role in prion diseases, where its misfolding and aggregation can cause fatal neurodegenerative conditions such as the bovine spongiform encephalopathy, scrapie of sheep and human Creutzfeldt – Jakob disease ( 2 ). The protein contains several high affinity binding sites for copper ions ( 3 ) and its structure evolved from a common ZIP (Zrt-and Irt - like

An alternative method to determine the diffusion coefficient for the shrinking core model

A new method to determine the effective diffusion coefficient of sorbate in sorbent granule based on the analytical solution of the shrinking core model (SCM) has been proposed. The experimental data presented by Lewandowski and Roe1 concerning the sorption of copper ions by alginate granules have been applied to compare the analytical and numerical methods. The results obtained by both methods are very close.