Suchergebnisse

A dental implant is a unique structure which can be used with a noninvasive method because it is inserted into the bone in part and extended extracorporally. This study presents an electronic device that is temporarily connected with the dental implant, and reports its effect on accelerating bone formation in the surrounding tissues in a canine mandibular model. A small sized and low power consumption biphasic electrical current (BEC) stimulator ASIC was developed and the surrounding tissue was exposed to continuousBECstimulation for 7 days with the parameters of 20 mA/cm2, 125 ms duration, and 100 pulses/s. After 2 (n¼5) and 5 weeks (n¼5), animals were sacrificed and the specimens were histomorphometrically evaluated. The newly formed bone area (BA) was 1.30 times (3 weeks, P<0.05) and 1.35 times (5 weeks, P<0.05) higher in the experimental group compared to the control group, respectively. Bone-implant contact (BIC) in 3-week specimens was 1.62 times (P<0.05) greater in the experimental group, while there was no statistically significant difference in 5-week specimens. Based on these results showing accelerated bone formation on and around the dental implant, it could be suggested that the latent time for osseointegration in dental implants can be reduced, and the success rate of implants in poor quality bone can be increased by using our device with BEC. ; Grant sponsors: Nano Bioelectronics and systems Research Center (ERC grant from KOSEF) (R11-2000-075-01001-0); Korea Research Foundation funded by the Korean Government (MOEHRD, Basic Research promotion Fund) (KRF-2006-311- D0098); MOCIE (Ministry of Commerce, Industry and Energy), Korea, under the integrated Circuit Design Education Center Multi Project Wafer Program

Cellulose-calcium silicate (CCS) nanocomposites were fabricated through an environment-friendly process from waste wood, glass, and clam shells. Effect of heat-treatment on synthesis of CCS nanocomposites was investigated in terms of the precursor ratio and firing temperature. The optimization of cellulose, silicon, and calcium ratio resulted in the low temperature synthesis and also reducing input energy and the production of toxic by-products. The synthesized CCS nanocomposites were examined for its versatility, especially regarding its ability to replace plastics. The resulting biodegradable material has the potential for use in a variety of applications, including reducing CO2 emissions.

The fields of toxicology and chemical risk assessment seek to reduce, and eventually replace, the use of animals for the prediction of toxicity in humans. In this context, physiologically based kinetic (PBK) modelling based on in vitro and in silico kinetic data has the potential to a play significant role in reducing animal testing, by providing a methodology capable of incorporating in vitro human data to facilitate the development of in vitro to in vivo extrapolation of hazard information. In the present article, we discuss the challenges in: 1) applying PBK modelling to support regulatory decision making under the toxicology and risk-assessment paradigm shift towards animal replacement; 2) constructing PBK models without in vivo animal kinetic data, while relying solely on in vitro or in silico methods for model parameterization; and 3) assessing the validity and credibility of PBK models built largely using non-animal data. The strengths, uncertainties, and limitations of PBK models developed using in vitro or in silico data are discussed in an effort to establish a higher degree of confidence in the application of such models in a regulatory context. The article summarises the outcome of an expert workshop hosted by the European Commission Joint Research Centre (EC-JRC) – European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), on "Physiologically-Based Kinetic modelling in risk assessment – reaching a whole new level in regulatory decision-making" held in Ispra, Italy, in November 2016, along with results from an international survey conducted in 2017 and recently reported activities occurring within the PBK modelling field. The discussions presented herein highlight the potential applications of next generation (NG)-PBK modelling, based on new data streams. © 2018 The Authors

The fields of toxicology and chemical risk assessment seek to reduce, and eventually replace, the use of animals for the prediction of toxicity in humans. In this context, physiologically based kinetic (PBK) modelling based on in vitro and in silico kinetic data has the potential to a play significant role in reducing animal testing, by providing a methodology capable of incorporating in vitro human data to facilitate the development of in vitro to in vivo extrapolation of hazard information. In the present article, we discuss the challenges in: 1) applying PBK modelling to support regulatory decision making under the toxicology and risk-assessment paradigm shift towards animal replacement; 2) constructing PBK models without in vivo animal kinetic data, while relying solely on in vitro or in silico methods for model parameterization; and 3) assessing the validity and credibility of PBK models built largely using non-animal data. The strengths, uncertainties, and limitations of PBK models developed using in vitro or in silico data are discussed in an effort to establish a higher degree of confidence in the application of such models in a regulatory context. The article summarises the outcome of an expert workshop hosted by the European Commission Joint Research Centre (EC-JRC) – European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM), on "Physiologically-Based Kinetic modelling in risk assessment – reaching a whole new level in regulatory decision-making" held in Ispra, Italy, in November 2016, along with results from an international survey conducted in 2017 and recently reported activities occurring within the PBK modelling field. The discussions presented herein highlight the potential applications of next generation (NG)-PBK modelling, based on new data streams.