[en] Accidental internal contamination of humans by uranium can induce radiological or chemical toxicity, their relative importance being dependent on the isotopic composition. The current approach for reducing the risk of biological effects is to administer chelating agents that will enhance the excretion of uranium. The results obtained with several phosphorus bearing compounds including phosphonic acids, diphosphonates, and phosphoalkylphosphates and with 3,4,3-LIHOPO, an effective agent for other actinides are presented here. The development of new approaches designed to optimise the decorporation of uranium carried out under the European Union Fourth Framework Program is described. (author)

[en] The article summarizes the biological importance of iron in the organism, primary and secondary causes of iron overload, complications in function of liver, heart and endocrine organs due to overload of iron, the pathophysiology of iron overload, transfusion risks associated with the iron overload, assessment of risk groups of patients suitable for chelation treatment fulfilling the indication criteria, treatment modalities of chelation therapy and its significance regarding the prevention and treatment effectiveness. (author)

[en] The ternary complex formation of metal ions with ligand in an aquatic solution has been of interest in various research fields such as synergistic extraction, spectrophotometry, spectrofluorometry, solubility and sorption of radionuclides in an environment. When the metal ion extraction based on its formation of a ternary complex with two additives shows much higher extraction efficiency as compared to the extractions by an individual additive, it is classified as a synergistic extraction. Synergistic extraction uses a neutral donor in combination with an acidic chelating ligand. The chelating ligand neutralizes the charge of a metal ion to form an uncharged extractable complex having sites for water molecules, which can be replaced by the neutral donors to form an organophilic adduct. The most common acidic chelating ligands are β-diketones or organophosphorous acids, and neutral donors are amine derivatives or organophosphorous compounds such as alkylphosphates and alklypohsphine oxides. Development of sensitive and selective analytical instruments such as ICP-AES and ICP-MS makes an analyst be free from the trouble to separate analyte. However, sometimes, the removal of matrix from an analyte is required to increase sensitivity and to decrease background level and hysteresis of an instrument. Solvent extraction is one of the most important techniques in concentration and purification of U(VI). The purpose of this study is an understanding of a ternary complex formation of U(VI) in the presence of pyridine derivatives and TBP. The solvent extraction technique was used, and the results was explained by a stability of U(VI)-chelating ligand complexes. The result of this study could be applied to the concentration and separation of U(VI) from the sea water

[en] In order to better analyze the influence of sewage on the viscosity of polymer solution, this paper uses BROOKFIELD viscometer to determine the viscosity value of solution. The results show that the viscosity decreases rapidly with the increase of the of polymer solution concentration of metal cations. Especially, the concentration of Mg²⁺ and Ca²⁺ have a great influence on the viscosity and the small increase of the concentration of Mg²⁺ and Ca²⁺ can lead to the decrease of the viscosity of HPAM solution. Na₂CO₄ was chosen as the complexing agent to improve the viscosity of HPAM solution, and the viscosity increasing rate of HPAM solution with the concentration of 1500 mg/L reached 33.2%. (paper)

[en] Plants form green leaf volatiles (GLVs) almost instantly after tissue disruption caused by damages, such as herbivore damage. This rapid formation of GLVs, namely GLV-burst, is an essential factor for the plants’ GLV-dependent direct and indirect defenses. However, mechanism of GLV-burst remains unknown. We observed that the formation of monogalactosyldiacylglycerol hydroperoxides (MGDG-OOHs) by Arabidopsis lipoxygenase 2 (AtLOX2) governs GLV-burst in Arabidopsis. Addition of a Ca²⁺ selective chelating reagent, BAPTA, during tissue disruption effectively suppressed the formation of MGDG-OOHs as well as GLV-burst. This suppression was relieved by the addition of Ca²⁺. Therefore, we propose that Ca²⁺-dependent activation of AtLOX2 facilitates GLV-burst formation as observed in leukotriene formation, which is regulated by Ca²⁺-dependent activation of LOXs in animal cells.

[en] The methods and results of laboratory experiment dealing with the properties of foams and their application to the decontamination of surfaces within the controlled zone of nuclear power plants are described. Experiments were carried out with selected specimens of materials commonly encountered within the controlled zone of the plant, such as stainless steel plates, epoxy paint, epoxy concrete and plastic floorings. The foams were generated by using laboratory and technological equipment. (author)

[en] During the past decade, many bifunctional chelating agents (BFCAs) have been studied, synthesized and used for radiopharmaceuticals especially for labeling of antibodies and regionally selective drugs. General researches for preparation of DTPA derivatives have been performed using cyclic DTPA dianhydride. Because one or two carboxylic groups of DTPA were used to conjugate with biomolecule results to lower chelating power for radionuclides. Our goal was to synthesize new bifunctional chelating agents for their application in development of new medical imaging and therapeutic agents. To obtain more effective new chelating agents, we focused on the development of DTPA derivatives whose original functional groups are intact. In our study, we described the synthesis of a DTPA analogue derived from lysine

[en] Highlights: • MMP-9-binding sequences of staphylococcal superantigen like 5 (SSL5) were identified. • The responsible regions of SSL5 for the binding are β1-3 and α4β9 regions. • β1-3 but not α4β9 region was ability to inhibit gelatinolytic activity of MMP-9. Staphylococcal superantigen like 5 (SSL5) is an exotoxin produced by S. aureus and has a strong inhibitory effect on MMP-9 enzymatic activity. However, the mechanism of inhibition remains unclear. We sought to identify the responsible regions of SSL5 for the interaction with MMP-9 by comparing a series of domain swap and deletion mutants of SSL5. Binding analyses revealed that SSL5 had two regions for binding to MMP-9 catalytic domain, β1-3 region (²⁵SKELKNVTGY RYSKGGKHYL IFDKNRKFTR VQIFGK⁶⁰) in N-terminal half and α4β9 region (¹³⁸KELDFKLRQY LIQNFDLYKK FPKDSKIKVI MKD¹⁷⁰) in C-terminal half. The collagen binding domain and zinc-chelating histidine residues of MMP-9 were not essential for the specific binding to SSL5. The domain swap mutants of SSL5 that conserved β1-3 but not α4β9 region inhibited the gelatinolysis by MMP-9, and the mutant of SSL7 that substituted β1-3 region to that of SSL5 acquired the binding and inhibitory activity. Furthermore, the polypeptide that harbored β1-3 region of SSL5 inhibited gelatinolysis by MMP-9. Taken together, SSL5 inhibits the MMP9 activity through binding to the catalytic domain, and the β1-3 region is responsible for the inhibition of proteolytic activity of MMP-9.

No abstract available

[en] In vitro experiments have been performed to elucidate the mechanisms by which chelators remove the radionuclides from the body. In the first part of this large-scale study, experiments have been performed to understand why the recommended chelators, DTPA and NaHCO₃, are ineffective for neptunium and uranium decorporation. Blood, liver and bone were isolated either after in vivo or in vitro contamination and the effect of various concentrations of DTPA or NaHCO₃ were tested for the dissociation of the biological complexes. The results showed that DTPA and NaHCO₃ were ineffective both in preventing the organ deposition of the neptunium and uranium and in removing them from the target organs. Other studies using sodium citrate of 3,4,3-Li-HOPO showed better efficiency than that observed with the recommended chelators. (author)