When Neurospora crassa is grown in the presence of Cu(II) ions, it accumulates the metal with the concomitant synthesis of a low molecular weight copper-binding protein. The molecule binds 6 g-atom of copper per mole protein (Mr = 2200) and shows a striking sequence homology to the zinc- and cadmium-binding vertebrate metallothioneins. Absorption, circular dichroism, and electron paramagnetic r...

Classical xerogels are robust, inexpensive and nontoxic materials with low-ordered nanoporous structures. In water streams where the pH is higher than the Point of Zero Charge, the surface of classical xerogels such as tetraethoxy orthosilan (TEOS) xerogel is negatively charged. It was assumed that a xerogel can work as a strong adsorbent for metal ions without further modification. Therefore, ...

Metal-on-metal bearings for total hip replacement (THR) are becoming increasingly popular. Improved wear characteristics mean that these articulations are being inserted into younger patients in the form of THR and resurfacing procedures. This has led to concerns regarding potential carcinogenicity because of the increased exposure to metal ions that the procedure brings. We have studied the se...

The peptide hormone gastrin binds two ferric ions with high affinity, and iron binding is essential for the biological activity of non-amidated forms of the hormone. Since gastrins act as growth factors in gastrointestinal cancers, and as peptides labelled with Ga and In isotopes are increasingly used for cancer diagnosis, the ability of gastrins to bind other metal ions was investigated system...

The stoichiometries and the affinity toward simple and paired metal ions of synthetic amyloid-beta(1-40) peptide (Abeta1-40) were investigated by electrospray ion trap mass spectrometry (ESI-MS), circular dichroism (CD), and atomic force microscopy (AFM). The results lead to the working hypothesis that pH-dependent metal binding to Abeta1-40 may induce conformational changes, which affect the a...

The metal ions constituents in plants reliable for determination of their medicinal, nutritional and toxicity properties. A novel, simple and accurate spectrophotometric method was developed for the simultaneous determination of Ag+, Cu2+ and Ni2+ ions in different medicinal plants without prior separation steps. This method was based on the different kinetic characteristics between the reactio...

An alomina-based nano adsorbent was prepared by modification of the external surface of γ-alumina (γ-Al2O3) nanoparticles with functional groups of a new Schiff base 4-[(2-hydroxy-3-methoxy-benzylidene)-amino]-5-methyl-2,4-dihydro-[1,2.4]triazole-3-thione] “L”. In order to the removal of Cr(VI) from aqueous solutions, we used the reaction of the sodium dodecyl sulfate coated nano-alumina with L...

Background: Orthodontics is a part of dentistry that includes preventive methods and correction of dental irregularities that need to be repositioned by functional and mechanical tools to provide an ideal occlusion and a beautiful face for patients. There are currently four metal arch wires used in orthodontic treatment: stainless steel alloy, cobalt-chromium alloy, nickel-titanium alloy, and b...

Lead(II)-induced cleavage can be used as a tool to probe conformational changes in RNA. In this report, we have investigated the conformation of M1 RNA, the catalytic subunit of Escherichia coli RNase P, by studying the lead(II)-induced cleavage pattern in the presence of various divalent metal ions. Our data suggest that the overall conformation of M1 RNA is very similar in the presence of Mg(...

n-propylsalicylidene based on silica as ion exchanger (ie) was used for the separation by complexation of mn2+, co2+, ni2+, cu2+, hg2+, cr3+, fe3+, and uo22+ from their parent solutions. ie and its metal complexes are characterized by elemental analysis, electronic and infrared spectra, in addition to thermal analysis in atmospheric pressure. the mode of chelation and the proposed geometric str...