A zirconia/tantalum biocermet: and evaluation for biomedical implant applications.

A biocermet made of zirconia/20 vol% tantalum (3Y-TZP/Ta) is a new composite with exceptional capabilities due to a combination of properties that are rarely achieved in conventional materials (high strength and toughness, cyclic fatigue resistance and flaw tolerance, wear resistance, corrosion resistance, electrical conductivity, ). In this study, for the first time, the biomedical performance of a 3Y-TZP/Ta biocermet was evaluated in detail. Its biocompatibility was assessed using mesenchymal stem cell culture.

3Y-TZP/Ta Biocermet as a Dental Material: An Analysis of the In Vitro Adherence of Streptococcus Oralis Biofilm and an In Vivo Pilot Study in Dogs.

The surface adhesion of bacterial cells and the in vivo biocompatibility of a new ceramic-metal composite made of zirconium dioxide and tantalum were evaluated. Within the framework of an in vitro study using the crystal violet staining and colony counting methods, a relatively similar adhesion of to the 3Y-TZP/Ta biocermet (roughness Ra = 0.12 ± 0.

Multicatalysis Combining 3D-Printed Devices and Magnetic Nanoparticles in One-Pot Reactions: Steps Forward in Compartmentation and Recyclability of Catalysts.

A tricatalytic compartmentalized system that immobilizes metallic species to perform one-pot sequential functionalization is described: a three-dimensional (3D)-printed palladium monolith, ferritic copper(I) magnetic nanoparticles, and a 3D-printed polypropylene capsule-containing copper(II) loaded onto polystyrene-supported 1,5,7-triazabicyclo[4.4.0]dec-5-ene (PS-TBD) allowed the rapid synthesis of diverse substituted 1-([1,1'-biphenyl]-4-yl)-1-1,2,3-triazoles.

Histological response of soda-lime glass-ceramic bactericidal rods implanted in the jaws of beagle dogs.

Bacterial and fungal infections remain a major clinical challenge. Implant infections very often require complicated revision procedures that are troublesome to patients and costly to the healthcare system. Innovative approaches to tackle infections are urgently needed.

In vitro and in vivo evaluation of a new zirconia/niobium biocermet for hard tissue replacement.

Metals and ceramics are commonly used in orthopaedics, dentistry and other load bearing applications. However, the use of ceramic matrix composites reinforced with biocompatible metals for heavy load-bearing hard tissue replacement applications has not previously been reported. In order to improve the reliability and the mechanical properties of biomedical implants, new zirconia-Nb composites have been recently developed.

Systematic review of brucellosis in the Middle East: disease frequency in ruminants and humans and risk factors for human infection.

A systematic review of studies providing frequency estimates of brucellosis in humans and ruminants and risk factors for Brucella spp. seropositivity in humans in the Middle East was conducted to collate current knowledge of brucellosis in this region. Eight databases were searched for peer-reviewed original Arabic, English, French and Persian journal articles; the search was conducted on June 2014.

Deproteinated bovine bone vs. beta-tricalcium phosphate as bone graft substitutes: histomorphometric longitudinal study in the rabbit cranial vault.

Objectives: This article aims to study differences in the bone formation and the graft resorption of two bone graft substitutes (BGS). Besides, it is our attempt to observe possible qualitative and quantitative differences in the bone reparation of the outer layer covered by collagen membrane and the uncovered inner layer in close contact with dura mater.

Material And Methods: Twelve rabbits were employed.

Printing in three dimensions with graphene.

Responsive graphene oxide sheets form non-covalent networks with optimum rheological properties for 3D printing. These networks have shear thinning behavior and sufficiently high elastic shear modulus (G') to build self-supporting 3D structures by direct write assembly. Drying and thermal reduction leads to ultra-light graphene-only structures with restored conductivity and elastomeric behavior.

A new biocompatible and antibacterial phosphate free glass-ceramic for medical applications.

In the attempt to find valid alternatives to classic antibiotics and in view of current limitations in the efficacy of antimicrobial-coated or loaded biomaterials, this work is focused on the development of a new glass-ceramic with antibacterial performance together with safe biocompatibility. This bactericidal glass-ceramic composed of combeite and nepheline crystals in a residual glassy matrix has been obtained using an antimicrobial soda-lime glass as a precursor. Its inhibitory effects on bacterial growth and biofilm formation were proved against five biofilm-producing reference strains.

Spatial, demographic and clinical patterns of Angiostrongylus vasorum infection in the dog population of Southern England.

A retrospective study was carried out to provide updated knowledge of the spatial pattern of Angiostrongylus vasorum infection in Southern England and to investigate associations between selected host characteristics (age, breed, sex), risk of infection and clinical presentation (cardiorespiratory signs v haemorrhagic diathesis). One hundred and forty-one cases diagnosed between April 1999 and July 2012 were compared with a control population of dogs referred to the same hospital. A significant association was found between haemorrhagic diathesis and breed but not for other host characteristics and clinical presentations.

Angiostrongylus vasorum in Great Britain: a nationwide postal questionnaire survey of veterinary practices.

The lungworm, Angiostrongylus vasorum, was first reported in indigenous dogs in southwestern England in 1980 and has since been recorded in Wales, southeastern England and, more recently, in the West Midlands, northern England and Scotland. The nationwide distribution of the parasite was evaluated using a postal questionnaire sent to 3950 small animal practices during 2009. Information was sought on the location of each practice, awareness of the parasite locally, number of cases diagnosed over the past year and whether diagnosis was based on clinical signs alone or supported by additional tests.

Bone loss at implant with titanium abutments coated by soda lime glass containing silver nanoparticles: a histological study in the dog.

The aim of the present study was to evaluate bone loss at implants connected to abutments coated with a soda-lime glass containing silver nanoparticles, subjected to experimental peri-implantitis. Also the aging and erosion of the coating in mouth was studied. Five beagle dogs were used in the experiments.

Cl-OH ion-exchanging process in chlorapatite (Ca5(PO4)3Cl(x)(OH)(1-x))--a deep insight.

We have synthesized large chlorapatite [ClAp, Ca(5)(PO(4))(3)Cl(x)(OH)(1-x), where x = 1] single crystals using the molten salt method. We have corroborated that the hexagonal symmetry P6(3)/m describes the crystal structure best, even though the crystals are synthetic and stoichiometric. Moreover, we have performed several thermal treatments on these ClAp crystals, generating new single crystals in the apatite system [Ca(5)(PO(4))(3)Cl(x)(OH)(1-x), where x ≤ 1], where the chloride anions (Cl(-)) were systematically substituted by hydroxyl anions (OH(-)).

Synthesis and characterisation of large chlorapatite single-crystals with controlled morphology and surface roughness.

This work describes the synthesis of chlorapatite single crystals using the molten salt method with CaCl(2) as a flux. By manipulating the processing conditions (amount of flux, firing time and temperature, and cooling rates) it is possible to manipulate the crystal morphology from microscopic fibres to large crystals (up to few millimetre long and ~100 μm thick). The crystal roughness can be controlled to achieve very flat surfaces by changing the melt composition "in situ" at high temperature.

Ruminant brucellosis in Upper Egypt (2005-2008).

Brucellosis is endemic among humans and ruminant in Egypt and recent reports suggest that its incidence may be increasing. In this study we describe the frequency of brucellosis among different ruminant species in Upper Egypt and its spatial distribution using the data generated by a large-scale control campaign undertaken between 2005 and 2008. A total of 120,090 individual animals of different ruminant species were tested during the campaign.

Maxillary sinus floor augmentation on humans: Packing simulations and 8 months histomorphometric comparative study of anorganic bone matrix and β-tricalcium phosphate particles as grafting materials.

The present study compares the behaviour of an anorganic bone matrix material and a synthetic β-Tricalcium phosphate employed as grafting materials in a sinus floor augmentation two step protocol in humans. In order to estimate the initial occupation level for the two materials, an 'in vitro' simulation has been performed to analyse macroporosity created due to particle packing in terms of porosity and interparticle distances. Grafting in the sinus floor augmentation was performed by filling the defects only with pure grafting materials without autogenous bone addition.

Impact of the implementation of rest days in live bird markets on the dynamics of H5N1 highly pathogenic avian influenza.

Live bird markets (LBMs) act as a network 'hub' and potential reservoir of infection for domestic poultry. They may therefore be responsible for sustaining H5N1 highly pathogenic avian influenza (HPAI) virus circulation within the poultry sector, and thus a suitable target for implementing control strategies. We developed a stochastic transmission model to understand how market functioning impacts on the transmission dynamics.

Reinforcing of a calcium phosphate cement with hydroxyapatite crystals of various morphologies.

A series of biocomposite materials was successfully prepared by reinforcing advanced calcium phosphate cement with hydroxyapatite fibrous and elongated plate-like particles. Powder X-ray diffraction showed that ball-milled biocomposite precursors (dicalcium and tetracalcium phosphates) entirely transform to a single phase hydroxyapatite end product within 7 h at 37 °C. Electron microscopy showed that the resultant biocomposites are constituted of nanoscaled cement particles intimately associated with the reinforcement crystals.

Herd contact structure based on shared use of water points and grazing points in the Highlands of Ethiopia.

The use of shared common water points (WPs) and grazing points (GPs) at two different levels of administrative aggregation (village and kebelle) in a region of the Highlands of Ethiopia was explored by means of a questionnaire survey and social network analysis. Despite GPs being more abundant than WPs (208 and 154, respectively), individual GPs provide more contact opportunities for animals. There was great variability in the contact structure of the selected villages within kebelles for both networks, with this variability being higher in the GP networks for each kebelle.

Contamination of food products with Mycobacterium avium paratuberculosis: a systematic review.

Although a causal link between Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn's disease has not been proved, previous studies suggest that the potential routes of human exposure to MAP should be investigated. We conducted a systematic review of literature concerning the likelihood of contamination of food products with MAP and the likely changes in the quantity of MAP in dairy and meat products along their respective production chains. Relevant data were extracted from 65 research papers and synthesized qualitatively.

Assessment and simulation of the implementation of brucellosis control programme in an endemic area of the Middle East.

Brucellosis is an important zoonosis in Middle Eastern countries. In this study we assessed the extent of the application of planned official brucellosis control programmes in Kafr El Sheikh governorate, Egypt and we used a stochastic simulation model to assess the probable impact of changes to the official control strategy on the dynamics of small-ruminant brucellosis. Our results show that <7% of female livestock were tested in any given year in the study area and that quarantine was not consistently applied to infected herds.

Risk associated with animals moved from herds infected with brucellosis in Northern Ireland.

The movement of cattle from herds infected with Brucella abortus was investigated in order to assess the control measures for eradication of brucellosis from the cattle population of Northern Ireland. Using recorded cattle movement data, a historical cohort study was designed and carried out to quantify the risk of seropositivity in bovine animals moved from herds infected with brucellosis. The study found that 3.

Effect of the calcium to phosphate ratio of tetracalcium phosphate on the properties of calcium phosphate bone cement.

Six different tetracalcium phosphate (TTCP) products were synthesized by solid state reaction at high temperature by varying the overall calcium to phosphate ratio of the synthesis mixture. The objective was to evaluate the effect of the calcium to phosphate ratio on a TTCP-dicalcium phosphate dihydrate (DCPD) cement. The resulting six TTCP-DCPD cement mixtures were characterized using X-ray diffraction analysis, scanning electron microscopy, and pH measurements.

Conceptual framework for avian influenza risk assessment in Africa: the case of Ethiopia.

The avian influenza (AI) epidemic is threatening Africa mainly because the flyways of migratory birds link the endemic and newly infected countries with disease-free areas in this continent and because of the risk of introduction through trade. Risk analysis provides a set of tools for supporting decision making by the veterinary services and other stakeholders, resulting in more effective surveillance and emergency preparedness. The risk assessment process could be split into three different steps: 1) risk release through the migratory birds and the official and unofficial poultry-product marketing chains; 2) risk exposure by means of studying interfaces among imported and exposed poultry and among wild and domestic birds; and 3) risk consequences for establishing the probability of AI spreading within the poultry population and the probability of it escaping detection.