X-ray powder diffraction and chemical analyses show that mammalian dental enamel apatite is an impure form of hydroxylapatite, Ca10(PO4)6(OH)2 (structure described in Elliott 1994). The major difference of enamel apatite from hydroxylapatite is in the presence of about 3 wt% CO3. Details of the crystallographic structures of carbonate-containing apatites (including minerals) are important becau...

novel collagen-based hydrogel nanocomposites were synthesized by graft copolymerization of acrylamide and maleic anhydrid in the presence of different amounts of montmorillonite, using methylenebisacrylamide (mba)and ammonium persulfate (aps) as crosslinker and initiator, respectively. the optimum amount of clay on the swelling properties of the samples was studied. it was found that the hydrog...

Owing to their structure and function, low-density lipoproteins (LDLs) are particularly susceptible to the oxidative modifications. To prevent against oxidative modification of LDL, L-carnitine, with endogenous small water-soluble quaternary amine possessing antioxidative properties, was used. The aim of this paper was to prove the in vitro influence of L-carnitine on the degree of oxidative mo...

A new selectophore was introduced for Cu2+ ions. Spectroscopic studies showed a selectivity of a new organic compound (L) toward copper ions and several transitional metal ions. Hence, L was utilized in designing several ion selective electrodes for these cations. In practice, Cu2+ ion selective electrode behaved Nernstian (slope of 27.95±0.3 mV decade-1) over a...

The secondary structures of amyloidogenic proteins are largely influenced by various intra and extra cellular microenvironments and metal ions that govern cytotoxicity. The secondary structure of a prion fragment, PrP(111-126), was determined using circular dichroism (CD) spectroscopy in various microenvironments. The conformational preferences of the prion peptide fragment were examined by cha...

Channels and transporters of monovalent ions are increasingly suggested as putative anticarcinogenic targets. However, the mechanisms involved in modulation of proliferation by monovalent ions are poorly understood. Here, we investigated the role of K+, Na+, and Cl(-) ions for the proliferation of Ehrlich Lettre ascites (ELA) cells. We measured the intracellular concentration of each ion in G(0...

An automated multi-channel continuous-flow analyzing system was constructed for the rapid measurement of both the tota} amino acid content and the L-gtutamate content of green tea infusions. i.-Glutamate in samples was oxidized and deaminated enzymaticatly in a channel -'ith a mini-reactor that "'as packed with i.-glutamate oxidase immebilized on glass beads, and the evolyed ammonium ions were ...

The adsorption of pyridine on a complete monolayer molybdenum oxide-Al203 catalyst was studied. Both Lewis and Bronsted acid sites are present on a catalyst with a Mo valence of -4.1. The orientation of adsorbed pyridine was studied by means of its interaction with surface OD groups, which leads to the formation of only 2-deuteriopyridine. The fraction of molybdenum ions active for hydrogenatio...