Hospital-associated pneumonia (HAP) is one of the most common infections acquired among hospitalized patients. HAP is associated with excess mortality and increased medical care costs. The rise in HAP due to antibiotic-resistant bacteria has resulted in more common administration of inappropriate antimicrobial treatment, with an associated increased risk of hospital mortality. Ventilator-associ...

Hydroxyapatite (HAP) and fluorapatite (FAP) are essential components of dental enamel and bone. In this paper, we report a computational study of the elastic properties of HAP and FAP using ab initio and force field techniques. We have obtained the HAP and FAP elastic stiffness constants in hexagonal symmetry by fitting the Hooke law for both the energy-strain and stress-strain relations. Our a...

The efficacy of hydroxyapatite (HAp) as a carrier was investigated to establish a method of local administration of bisphosphonates (Bps), which has currently been administered systemically. HAp granules (300-500 microm in size) with different physicochemical features were prepared by altering the sintering temperature. To ascertain the physicochemical properties of the HAp granules, their crys...

Hydroxyapatite (HAP, Ca10(PO4)6(OH)2) nanoparticles with controlled materials properties have been synthesized through a two-step hydrothermal aging method to investigate fibronectin (Fn) adsorption. Two distinct populations of HAP nanoparticles have been generated: HAP1 particles had smaller size, plate-like shape, lower crystallinity, and more negative ζ potential than HAP2 particles. We then...

The aim of this study was to evaluate the in vitro response of osteoclast-like cells (RAW 264.7 cells) to a bioactive hydroxyapatite (HAP) surface that was modified using the 30% phosphoric acid-etching procedure reported in our previous paper (2013). The cells on the bioactive HAP surface were multinucleated and were larger than those on the untreated HAP surface. The cell occupancies were gre...

Generally, a solution nucleation model is used to study biomineralization kinetics. However, we found that the amorphous calcium phosphate (ACP)-mediated hydroxyapatite (HAP) nucleation in simulated body fluids (SBF) had a different profile from the linear relationship between ln J and ln(-2) S (J, nucleation rate; S, supersaturation). This behaviour was alternatively explained by a developed h...

Hydroxyapatite (HAp) nanorod embedded composite was prepared using poly (vinyl alcohol) (PVA) as a matrix with different weight percentages (wt. %) The role of PVA composition on the crystallite size, degree of crystallinity, functional groups and morphology of nanocomposites were characterised by XRD, FTIR, and TEM analysis. The results indicated that the size and crystallinity of HAp nano par...

It is well known that clinical bleaching can be achieved with a solution of 30% hydrogen peroxide (H2O2) or H2O2/titanium dioxide (TiO2) combination. This study examined the hypothesis that TiO2 coated with hydroxyapatite (HAp-TiO2) can generate reactive oxygen species (ROS). ROS are generated via photocatalysis using electron spin resonance (ESR). The bleaching properties of HAp-TiO2 in the pr...

A new approach to enhancing proton conductivity of ceramics is demonstrated by aligning proton conductive pathways and eliminating resistive grain boundaries. Hydroxyapatite (HAP) membranes are synthesized by multistage crystallization onto palladium. The synthesis involves three steps: electrochemical deposition of HAP seeds, secondary hydrothermal crystallization onto the seed layer to promot...

Nanoparticulate composites of hydroxyapatite (HAp) and chitosan were synthesized by ultrasound-assisted sequential precipitation and characterized for their microstructure at the atomic scale, surface charge, drug release properties, and combined antibacterial and osteogenic response. Crystallinity of HAp nanoparticles was reduced because of the interference of the surface layers of chitosan wi...