Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, ure...

The hydroxyapatite (HAP) with variable chemical substitutions has been considered as the major component in the mineralized part of bones. Various metastable crystalline phases have been suggested as transitory precursors of HAP in bone, but there are no consensuses as to the nature of these phases and their temporal evolution. In the present study, we cultured rat calvarial osteoblasts with as...

Inositol trisphosphate and cyclic ADP-ribose release Ca2+ from the endoplasmic reticulum via inositol trisphosphate and ryanodine receptors, respectively. By contrast, nicotinic acid adenine dinucleotide phosphate may activate a novel Ca2+ channel in an acid compartment. We show, in two-photon permeabilized pancreatic acinar cells, that the three messengers tested could each release Ca2+ from t...

Various reports have demonstrated that the sphingolipids sphingosine and sphingosine-1-phosphate are able to induce Ca2+ release from intracellular stores in a similar way to second messengers. Here, we have used the sea urchin egg homogenate, a model system for the study of intracellular Ca2+ release mechanisms, to investigate the effect of these sphingolipids. While ceramide and sphingosine-1...

This study was carried out to identify the cellular component activating the histamine-stimulated Ca2+ entry in vas-deferens-derived DDT1 MF-2 cells. H1-histaminoceptor stimulation resulted in a rise in intracellular Ca2+ concentration, caused by Ca2+ release from inositol phosphate-sensitive Ca2+ stores and Ca2+ entry from the extracellular space, accompanied by a transient Ca(2+)-activated ou...

In this study, transport behaviors of graphene oxide (GO) in saturated uncoated (i.e., clean sand) and goethite-coated sand porous media were examined as a function the phosphate. We found that phosphate enhanced GO over wide range solution chemistry pH 5.0–9.0 presence 10 mmol/L Na+ or 0.5 Ca2+). The results mainly ascribed to increase electrostatic repulsion between nanoparticles media. Meanw...

Synthetic calcium phosphates, e.g., hydroxyapatite (HAP) and tricalcium phosphate (TCP), are the most commonly used bone-graft materials due to their high chemical similarity natural hydroxyapatite—the inorganic component of bones. Calcium in form a free ion or bound complexes plays key role many biological functions, including bone regeneration. This paper explores possibility increasing Ca2+-...