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ABSTRACT Considerable efforts have been devoted toward the development of electrospun scaffolds based on poly(ε-caprolactone) (PCL) for bone tissue engineering. However, most of previous scaffolds have lacked the structural and mechanical strength to engineer bone tissue constructs with suitable biological functions. Here, we developed bioactive and relatively robust hybrid scaffolds composed of diopside nanopowder embedded PCL electrospun nanofibers. Incorporation of various concentrations of diopside nanopowder from 0 to 3 wt % within the PCL scaffolds notably improved tensile strength (eight-fold) and elastic modulus (two-fold). Moreover, the addition of diopside nanopowder significantly improved bioactivity and degradation rate compared to pure PCL scaffold which might be due to their superior hydrophilicity. We investigated the proliferation and spreading of SAOS-II cells on electrospun scaffolds. Notably, electrospun PCL-diopside scaffolds induced significantly enhanced cell proliferation and spreading. Overall, we concluded that PCL-diopside scaffold could potentially be used to develop clinically relevant constructs for bone tissue engineering. However, the extended in vivo studies are essential to evaluate the role of PCL-diopside fibrous scaffolds on the new bone growth and regeneration. Therefore, in vivo studies will be the subject of our future work. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44433. [ABSTRACT FROM AUTHOR]

The preparation and bioactivity evaluation of glass-ionomer cement (GIC) based on the composition of SiO2-Al2O3-CaO-Na2O-P2O5-F is described. Cements were characterized by XRD (X-ray powder diffraction) and BET, SEM (scanning electron micrograph), TEM, and EDAX analysis. The effects of P2O5on strengths and bioactivity of GIC were investigated. The effect of adding P2O5on the bioactivity of GIC was examined in simulated body fluid (SBF) followed by structural characterization using SEM and atomic absorption analysis. Results clearly show that the addition of P2O5to the cement structure improved bioactivity properties of the glass. Supplemental materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfur, and Silicon and the Related Elementsto view the free supplemental file. [ABSTRACT FROM PUBLISHER]

Introduction: Glass-ionomer cements (GICs) are one of the most important restorative materials in dentistry. Similarly, hydroxyapatite (HA) is of the most well known bioceramics. The aim of this study was to prepare a type of glass-ionomer cement with nano-particles of hydroxyapatite to improve GIC bioactivity and compressive strength. Materials and Methods: Natural HA particles were extracted from animal bone. The ceramic component of GIC was produced by melting and characterized. HA particles were incorporated into the cement component of GI at 1, 3, 5 and 7 weight percentages. Bioactivity and compressive strength of GIC\HA composite were evaluated in a simulated body fluid (SBF). One-way ANOVA was used for data analysis (n = 3). Results: The results of characterization tests confirmed the production of GIC using the melting technique. Amorphous and glassy structure of GIC powder and its proper chemical composition were verified by characterization tests. The results of soaking test in SBF showed increased bioactivity of GIC/HA composite. Finally, the results of compressive tests showed that incorporating HA up to 5 wt% would not decrease the compressive strength of GIC. Conclusion: GIC/HA nano-composite with 5 wt% of HA was the most appropriate sample regarding its bioactivity and mechanical properties for dental applications. Introducing this novel nano-composite can play an important role in improving the properties of glass-ionomer cements. [ABSTRACT FROM AUTHOR]

Morphine withdrawal increases locomotor sensitisation, relapse and impair regulation of serotonin system. We evaluated the effectiveness of Raha syrup on the cerebrospinal fluid (CSF) serotonin levels following locomotor sensitisation in morphine-withdrawn rats receiving the opium tincture (OT). Morphine withdrawal rats gavaged daily with OT and Raha syrup (for 30 days) and then challenged with morphine and evaluated for locomotor activity and CSF serotonin levels before morphine challenge and 2 weeks after cessation of treatment. Raha syrup attenuated locomotor activity, increased the CSF serotonin after morphine challenge, and continued 2 weeks after cessation of treatment in rats receiving OT. Whereas, rats receiving OT alone after morphine challenge exhibited a relative decrease in locomotor activity, without changing CSF serotonin. Raha syrup attenuated locomotor sensitisation in morphine-withdrawn rats receiving OT probably by increasing serotonin. Therefore, administration of Raha syrup along with OT may benefit to treatment relapse in addicts receiving OT maintenance treatment.

Background: The most important limitation of glass ionomer cements (GICs) is the weak mechanical properties. Our previous research showed that higher mechanical properties could be achieved by addition of forsterite (Mg2SiO4) nanoparticles to ceramic part of GIC. The objective of the present study was to fabricate a glass ionomer- Mg2SiO4 nanocomposite and to evaluate the effect of addition of Mg2SiO4 nanoparticles on bioactivity and fluoride release behavior of prepared nanocomposite., Materials and Methods: Forsterite nanoparticles were made by sol-gel process. X-ray diffraction (XRD) technique was used in order to phase structure characterization and determination of grain size of Mg2SiO4 nanopowder. Nanocomposite was fabricated via adding 3wt.% of Mg2SiO4 nanoparticles to ceramic part of commercial GIC (Fuji II GC). Fluoride ion release and bioactivity of nanocomposite were measured using the artificial saliva and simulated body fluid (SBF), respectively. Bioactivity of specimens was investigated by Fourier transitioned-infrared spectroscopy (FTIR), scanning electronmicroscopy (SEM), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and registration of the changes in pH of soaking solution at the soaking period. Statistical analysis was carried out by one Way analysis of variance and differences were considered significant if P < 0.05., Results: The results of XRD analysis confirmed that nanocrystalline and pure Mg2SiO4 powder was obtained. Fluoride ion release evaluation showed that the values of released fluoride ions from nanocomposite are somewhat less than Fuji II GC. SEM images, pH changes of the SBF and results of the ICP-OES and FTIR tests confirmed the bioactivity of the nanocomposite. Statistical analysis showed that the differences between the results of all groups were significant (P < 0.05)., Conclusion: Glass ionomer- Mg2SiO4 nanocomposite could be a good candidate for dentistry and orthopedic applications, through of desirable fluoride ion release and bioactivity.