This is part of a larger study designed to investigate the action of particulate metals of orthopaedic interest on tissues. Damaging effects were determined by cytological examination and the assay of two enzymes. Lactic dehydrogenase (LDH) if released into the supernatant indicates a damaged cell membrane; decreased intracellular levels of glucose-6-phosphate dehydrogenase (G6PD) indicates a l...

It is well-known that nanoparticles could cause toxic effects in cells. Alloy nanoparticles with yet unknown health risk may be released from cardiovascular implants made of Nickel-Titanium or Cobalt-Chromium due to abrasion or production failure. We show the bio-response of human primary endothelial and smooth muscle cells exposed to different concentrations of metal and alloy nanoparticles. N...

This study aimed at comparing amounts of nickel (Ni) and chromium (Cr) released from brackets from different manufacturers in simulated oral environments. 280 brackets were equally divided into 7 groups according to manufacturer. 6 groups of brackets were stainless steel, and 1 group of brackets was made of a cobalt-chromium alloy with low Ni content (0.5%). International standard ISO 10271/200...

Introduction: The process of mixing metals with non metals is called alloying, and the resulting mixture alloy. Alloys are composed of at least two elements, from which one must be metal. They are divided into alloys for fixed partial dentures-FPD (golden, golden-platinum, silver-palladium alloys, alloys for soldering and alloys for metal-ceramic dentures). Purpose: the main purpose is to inves...

AuZn undergoes a shape-memory transition at 67 K. The de Haas-van Alphen effect persists to 100 K enabling the observation of a change in the quantum oscillation spectrum indicative of a catastrophic Fermi surface reconstruction at the transition. The coexistence of both Fermi surfaces at low temperatures suggests an intrinsic phase separation in the bulk of the material. In addition, Dingle an...

BACKGROUND In Brazil, despite the recommendations of the Brazilian Society of Hemodynamics and Interventional Cardiology, the National Health System has not yet approved the use of drug-eluting stents. In percutaneous coronary interventions performed in the public and part of the private health care system, bare metal stents are used as the only option. Therefore, new information on bare metal ...

Optimized and validated spectrophotometric methods have been proposed for the determination of iron and cobalt individually and simultaneously. 2-hydroxy-1-naphthaldehyde-p-hydroxybenzoichydrazone (HNAHBH) reacts with iron(II) and cobalt(II) to form reddish-brown and yellow-coloured [Fe(II)-HNAHBH] and [Co(II)-HNAHBH] complexes, respectively. The maximum absorbance of these complexes was found ...

A method for the simultaneous spectrophotometric determination of nickel, cobalt and copper based on the formation of their complexes with 2-(2-Thiazolylazo)-p-Cresol (TAC) in micellar media of Triton X-100 is proposed. The absorbance spectra were recorded in the range of 500 to 800 nm. The linear concentration range for nickel, cobalt and copper in solution calibration sets were 0.05–1.80, 0.1...

The total hip arthroplasty using metal on metal articulation with stainless steel was first introduced in 1938 by Wiles and the modification of this articulation with cobalt-chrome has been performed by many other orthopedic surgeons. After the McKee’s report on the poor result as high as 50% of failure rate during 15 years follow-up in 1972, the use of metal on metal articulation was decreased...