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Surface treatment of implants facilitates osseointegration, with nanostructured surfaces exhibiting accelerated peri-implant bone regeneration. This study compared bone-to-implant contact (BIC) in implants with hydroxyapatite (HA), sand-blasted and acid-etched (SLA), and SLA with calcium (Ca)-coated (XPEED®) surfaces. Seventy-five disk-shaped grade 4 Ti specimens divided into three groups were prepared, with 16 implants per group tested in New Zealand white rabbits. Surface characterization was performed using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), digital microscopy, and a contact angle analyzer. Cell viability, proliferation, and adhesion were assessed using MC3T3-E1 cells. Apatite formation was evaluated using modified simulated body fluid (m-SBF) incubation. After 4 weeks of healing, the outcomes reviewed were BIC, bone area (BA), removal torque tests, and histomorphometric evaluation. A microstructure analysis revealed irregular pores across all groups, with the XPEED group exhibiting a nanostructured Ca-coated surface. Surface characterization showed a crystalline CaTiO3 layer on XPEED surfaces, with evenly distributed Ca penetrating the implants. All surfaces provided excellent environments for cell growth. The XPEED and SLA groups showed significantly higher cell density and viability with superior osseointegration than HA (p < 0.05); XPEED exhibited the highest absorbance values. Thus, XPEED surface treatment improved implant performance, biocompatibility, stability, and osseointegration. [ABSTRACT FROM AUTHOR]

Biofouling is the buildup of marine organisms on a submerged material. This research tests the efficacy of phosphonium ion gels comprising phosphonium monomers ([P444VB][AOT] and [P888VB][AOT]) and free ionic liquid ([P4448][AOT], [P88814][AOT]) (10 to 50 wt%), varying copper(II) oxide biocide concentrations (0 to 2 wt%), and the docusate anion [AOT]− for added hydrophobicity. The efficacy of these formulations was tested using a seachest simulator protected from light and tidal currents in New Zealand coastal waters over the summer and autumn periods. Anti-fouling performance was correlated with the hydrophobicity of the surface (water contact angle: 14–131°) and biocide concentration. Formulations with higher hydrophobicity (i.e., less free ionic liquid and longer alkyl chain substituents) displayed superior anti-fouling performance. The presence of the copper(II) biocide negatively affected anti-fouling performance via significant increases to hydrophilicity. No correlation was observed between antimicrobial activity and anti-fouling performance. Overall, phosphonium ion gels show potential for combining anti-fouling and foul release properties. [ABSTRACT FROM AUTHOR]

Necessity to develop the efficient targeted delivery of highly potent immunosuppressant for IBD in order to avoid surgical procedure, led to fabrication and evaluation of its anti-inflammatory potential. Previously formulated cyclosporine A (Cyp A) into enteric coated capsules was further evaluated for its site-specificity in the treatment of TNBS induced colitis. Contact angle measurement studies showed excellent spreadability of the developed formulation over the hydrophilic biological tissue substrate. HET-CAM study demonstrates that the formulation prepared is nonirritant to the highly vascular tissues and hence can be used for the immunological sensitive tissues like inflamed intestine in IBD. Further the developed formulation has been characterized for site specificity to distal parts of intestine by pharmacokinetic studies. The appearance of drug in systemic circulation at approximately 5 hours in New Zealand strain of rabbits confirms drug delivery at distal parts of intestine. Significant reduced levels of TNF-α, IL-6 and IL-10 in drug treated animals signifies inhibition of inflammatory reactions at the TNBS treated site. Simultaneously, the change in body weight of same group of animals was observed for 15 days. Results showed a marginal recovery of body weight in Cyp A treated TNBS induced colitis animals. In conclusion, all in vitro and in vivo results confirm the successful site specific delivery and anti-inflammatory efficacy of developed formulation of Cyp A in TNBS induced colitis in New Zealand rabbits. [ABSTRACT FROM AUTHOR]

Dynamic wetting of the adaxial leaf surfaces of several New Zealand native plants has been studied using water drops, contact angle measurements and drop impact experiments. Three native plants (Arthropodium bifurcatum,Euphorbia glaucaandVeronica albicans) are identified as superhydrophobic, having advancing contact angles >160°, with <12° hysteresis and <10° roll off angle. These data are comparable to leaves of the lotus (Nelumbo nucifera), an international superhydrophobicity benchmark. Scanning electron microscopy reveals a range of epidermal microstructures and submicron epicuticle wax textures on native leaves, including superhydrophobic microstructures that are similar to those found on exotic leaves. Drop impacts onN. nucifera, A. bifurcatumandE. glaucawere filmed using a high speed camera at Weber number between 15 and 200. Drops impacting on the two native plants exhibited asymmetry due to vascular bundles on the leaf surfaces. Biomimicry and dynamic wetting are important for development of industrial superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

The amount of natural fat in sheep's skin varies significantly, and this depends upon the animal origin, sex, age, etc. In wool acquired from sheep's skin from Australia and New Zealand, this content can account for up to 50% of dry skin weight. Fats are triglycerides of saturated fatty acids. These fats can cause complications in the presence of excessive natural fat, rancidification and oxidation; due to tanning, dyeing and finishing operations become tedious. The defects reveal themselves in the form of spume and objectionable odor in leather. If the natural fat content in the raw material is high, as is usually the case with sheep's skin, it must be removed. The process of fat or grease removal is called degreasing which is best carried out after pickling process. Fat dissolving solvents such as kerosene, methylene chloride, and trichloroethylene are employed for degreasing. Since these solvents are water insoluble, they cannot be effectively used for degreasing wet pelts. These solvents are therefore used along with emulsifiers (preferably non-ionic), which disperse the solvent in water, thus facilitating its entry inside the pelt. This paper attempts to study the degreasing action of secondary butyl ether and formulation (solvent and emulsifier) in comparison with a commercial product which is the global market leader in leather degreasing segment. This experimental study shows that an improved degreasing action was achieved with the formulation comparable to the commercial degreasing agent. [ABSTRACT FROM AUTHOR]

This study aimed to fabricate a hierarchical tantalum scaffold mimicking natural bone structure to enhance osseointegration. Porous tantalum scaffolds (p-Ta) with microgradients were fabricated by selective laser melting according to a computer-aided design model. Electrochemical anodization produced nanotubes on the p-Ta surface (p-Ta-nt). SEM verified the construction of a unique nanostructure on p-Ta-nt. Contact angle and protein adsorption measurements demonstrated that p-Ta-nt have enhanced hydrophilicity and protein absorption. MC3T3-E1 preosteoblasts showed increased filamentous pseudopods and comparable cell proliferation when cultured on p-Ta-nt. Osteogenic marker gene (Osterix, Runx2, COL-I) transcription was significantly upregulated in MC3T3-E1 cells cultured on p-Ta-nt after 7 days. After implantation into the femurs of New Zealand white rabbits for 2 weeks, histological examination found improved early osseointegration in the p-Ta-nt group. This study showed that a hierarchical tantalum structure could enhance early osteogenic effects in vitro and in vivo. Schematic representation of the hierarchical tantalum scaffold mimicking natural bone structure. Porous tantalum scaffolds (p-Ta) were fabricated by selective laser melting. The nanotubes on the p-Ta surface (p-Ta-nt) were produced by electrochemical anodization. In vitro studies showed the satisfactory biocompatibility and osteoinduction to MC3T3-E1 cells. In vivo study showed the p-Ta-nt scaffold enhanced early osseointegration in a rabbit femur implant model. [Display omitted] [ABSTRACT FROM AUTHOR]

A bioactive micro/nanostructured calcium phytate coating was successfully prepared on titanium surfaces by chemical conversion deposition, mainly through hydrothermal treatment of a mixed solution of phytic acid and saturated calcium hydroxide solution. Ultraviolet radiation was carried out to improve the adhesion of the coating to the titanium substrate. Pure titanium with a sandblasted/acid-etched surface was used as the control group. The topography and chemical composition of the modified surfaces were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDX), and static water contact angle measurement. A pull-off test was performed to measure the coating-to-substrate adhesion strength. Bovine serum albumin was used as a model to study the protein adsorption effect. Cells were cultured on titanium surfaces for 7 days in osteogenic differentiation medium, then the osteoblast compatibility in vitro were explored by alkaline phosphatase and alizarin red staining. After 1, 2, 4 and 8 wks of immediate implantation of titanium implants into the mandibles of New Zealand white rabbits, biological effects in vivo were researched by microcomputed tomography analysis and histological evaluation. The results indicated that the roughness and hydrophilicity of the modified surfaces with micro/nanostructure remarkably increased compared to those of the control group. The pull-off test showed the average adhesion strength at the coating–substrate interface to be higher than 13.56 ± 1.71 MPa. In addition, approximately 4.41 mg/L calcium ion was released from the calcium phytate micro/nano coatings to the local environment after 48 h of immersion. More importantly, the micro/nanostructure titanium substrates significantly promoted cellular differentiation in vitro and in vivo. After 8 wks, the bone implant contact ratio (BIC, %) of the modified implants was higher than that of the control group, at 94.09 ± 0.55% and 86.18 ± 1.99% (p < 0.05). Overall, this study provided new insights into the factors promoting early osseointegration of titanium alloys, which had great potential not only for dental implants but also for various other biomaterial applications. Unlabelled Image • Micro/nanostructured coating was fabricated by chemical conversion deposition. • Titanium implant is gifted with a stable and superior hydrophilicity. • The calcium-decorated surface releases calcium ions rapidly. • Calcium phytate coating accelerates the osseointegration at an early stage. [ABSTRACT FROM AUTHOR]

This study investigates the simultaneous effect of substrate nanostructuring by severe plastic deformation and surface modification by SLActive on surface characteristics of CP-Ti grade 2 and evaluates the biocompatibility of it for use as implant material by in-vivo test. SLActive surface modification method is a modified SLA process that includes sandblasting, acid-etching, and cleaning by N 2 in a vacuum chamber. To this end, the structure CP-Ti grade 2 was refined by applying the equal channel angular pressing (ECAP) method. Surface morphology, roughness, and wettability of coarse-grained (CG) and ultrafine-grained (UFG) CP-Ti and Ti-6Al-4V were determined after SLActive. It was seen that after surface modification of the samples by SLActive, the excellent wettability with a drop contact angle of about 0° was achieved for SLActived specimens. For the in-vivo test, the implants of each three groups were embedded in the femur of white New Zealand rabbits. In order to assess the osseointegration of implants, histological analysis, and pull-out tests were conducted. Results showed suitable osseointegration between implant and bone for every three groups, but the value of removal torque was higher for UFG-Ti. As is realized UFG-Ti sample surface modified by SLActive could be a suitable choice among the candidates to be used as a material in the manufacturing of dental implants. [ABSTRACT FROM AUTHOR]