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The biochemical functions of the Cbfa1 core-binding factor were characterized in fetal mice with mutated Cbfa1 genes. The mutated mice died after birth due to a complete lack of bone formation that was induced by the disruption of the Cbfa1 gene. Histological analysis of the skeleton of the mice indicated the presence of low levels of osteopontin and osteolacin. Furthermore, maturational arrest occured during the early stage of osteoblast differentiation in the mutated mice embryos.

The aim of this study was to compare the volumetric changes and the new bone microarchitecture in human maxillary sinuses augmented with bioactive glass (Biogran) alone, bioactive glass combined with autogenous bone graft (1:1), or autogenous bone graft alone. Twelve maxillary sinuses were grafted with bioactive glass (group 1), nine with bioactive glass mixed with autogenous bone graft 1:1 (group 2), and 12 with autogenous bone graft (group 3). Patients underwent cone beam computed tomography 15 days after the procedure to determine the initial volume of the graft (T1) and again 6 months later (T2). Biopsies were obtained at the time of dental implant placement and were subjected to micro-computed tomography. The volumetric change was 44.2% in group 1, 37.9% in group 2, and 45.7% in group 3 ( P > 0.05). The trabecular microarchitecture results showed that the materials used in groups 1 and 2 were good bone substitutes. However, the addition of 50% bioactive glass to autogenous bone graft improved the microarchitecture of the graft. Furthermore, the results for volumetric changes indicated that bioactive glass, its association with autogenous bone graft in a 1:1 ratio, and autogenous bone graft alone have similar resorption. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the use of beta-tricalcium phosphate (β-TCP) (chronOS) with autogenous bone grafts alone in maxillary sinus elevation surgery. The test samples were β-TCP alone, β-TCP mixed with autogenous bone grafts (1:1), and autogenous bone grafts alone. Twelve maxillary sinuses were grafted with β-TCP (group 1), nine with β-TCP + autogenous bone graft (group 2), and 12 with autogenous bone graft (group 3). After 6 months, biopsies were obtained concurrent to the placement of dental implants; these were subjected to histomorphometric analysis and immunohistochemical analysis for runt-related transcription factor 2 (RUNX2) and vascular endothelial growth factor (VEGF). The average bone formation in group 1 was 46.3 ± 11.6% in the pristine bone region, 47.6 ± 9.9% in the intermediate region, and 44.8 ± 22.1% in the apical region; in group 2, values were 35.0 ± 15.8%, 32.5 ± 13.7%, and 32.8 ± 16.0%, respectively; in group 3, values were 43.1 ± 16.0%, 31.0 ± 13.0%, and 46.1 ± 16.3%, respectively. Immunostaining of samples in group 2 showed high cellular activity and immature bone; this differed from groups 1 and 3, in which mature bone was demonstrated. Thus, this study showed that β-TCP presents the same behaviour as autogenous bone graft, which makes it a good bone substitute. [ABSTRACT FROM AUTHOR]

This systematic review evaluated the efficacy of the morning fasting serum C-terminal telopeptide (CTX) test in predicting the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ). A comprehensive search of studies published up to March 2016, and listed in the PubMed/MEDLINE, Web of Science, and Cochrane Library databases, was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. This review has been registered in the PROSPERO international prospective register of systematic reviews (CRD42016036717). The search identified 542 publications; eight studies were finally deemed eligible for inclusion according to the study criteria. These studies included a total 1442 patients (mean age 66.7 years). The most prescribed drug was alendronate, with osteoporosis being the most frequent indication for the prescription of bisphosphonates. Tooth extraction was the most common trigger for BRONJ. Of all patients evaluated after bisphosphonate treatment, only 24 (1.7%) developed BRONJ. All eight of the selected studies found that CTX levels were not predictive of the development of BRONJ. In conclusion, this systematic review indicates that the CTX test has no predictive value in determining the risk of osteonecrosis in patients taking bisphosphonates. [ABSTRACT FROM AUTHOR]

The purpose of this systematic review was to perform a comparative analysis of the use or not of graft material in maxillary sinus lift surgery. Relevant studies published in the last 10 years were identified through a search of the PubMed/MEDLINE, ScienceDirect, and Cochrane Library databases and were assessed against the study inclusion and exclusion criteria. The initial search resulted in 1037 articles. After applying the inclusion and exclusion criteria, 16 articles remained. Four hundred and thirty-six patients were followed up over a postoperative period ranging from 6 months to 11 years. In total, 868 implants were installed in 397 maxillary sinuses. The implant survival rate was 96.00% for surgeries performed without graft material and 99.60% for those in which biomaterial was used, within a follow-up period of 48 to 60 months. In conclusion, maxillary sinus lift surgery, with or without graft material, is a safe procedure with a low complication rate and predictable results. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate bone healing at the bone–implant interface in rats with induced osteoporosis. The rats underwent a bilateral ovariectomy (OVX) and were fed a low calcium and phosphate diet. The OVX rats were divided into three groups: one was treated with raloxifene (OVX-RAL), one with alendronate (OVX-ALE), and one received no medication (OVX-NT). The control group rats (SHAM-DN) underwent sham surgery and were fed a normal diet. Each animal received one implant in each tibia: a machined surface implant in the right tibia and an implant with surface etching in the left tibia. All animals were euthanized after 42 days. Analysis of variance (ANOVA) and Tukey post hoc tests were applied to the biomechanics (reverse torque) and bone–implant contact (BIC) data ( P < 0.05). The RAL and ALE groups showed improved peri-implant bone healing. However, the ALE group showed no significant difference from the OVX-NT group. Surface treatment promoted higher corticalization at the bone–implant interface, but showed the same characteristics of mature bone and bone neoformation in concentric laminations as the machined implant. There were no statistically significant differences in reverse torque ( P = 0.861) or BIC ( P = 0.745) between the OVX-RAL and SHAM-DN groups. Therefore, the use of raloxifene resulted in good biomechanical, BIC, and histological findings in the treatment of induced osteoporosis in rats. [ABSTRACT FROM AUTHOR]

Abstract: Partial failure of a bridge may or may not lead to further damage or even to the collapse of the entire bridge. The difference arises from the redundancy of the bridge, and this issue attracts many researchers and engineers in recent years. Herein the post-member-failure analysis method of a steel truss bridge is studied. For the investigation of redundancy, simple analysis is preferred since a number of analyses are required in general. However, the present study reveals that static analysis yields quite different result from that due to dynamic analysis. A post-member-failure analysis method is then proposed. Example problem confirms the effectiveness of the proposed method while it requires computational time only as much as the static analysis does. [Copyright &y& Elsevier]

Abstract: A model for interphase precipitation with the ledge mechanism, based on a eutectoid reaction, has been developed and combined with the finite interface solute drag model and a numerical solution of the diffusion equations inside the migrating phase interface. In the model, niobium flows in two directions, i.e. perpendicular to the direction of the ledge migration by eutectoid-like reaction and simultaneously parallel to the direction of the ledge migration inside the ledge interface. The difference between ledge transformation and typical phase transformation is compared using this model and the effects of row spacing, temperature and segregation energy are discussed. The calculation results using the model are compared with experimental results and the critical driving force for interphase precipitation is evaluated. The estimations of the niobium carbide precipitation using this model are in good agreement with experimental results. [Copyright &y& Elsevier]

Abstract: The interphase precipitation in niobium steel has been investigated. In the present work, the austenite/ferrite transformation speed should be fast due to hot deformations, and interphase precipitation can be observed after 10s isothermal holding in the temperature range 923–1023K. The dominant interphase precipitation is planar and is not oriented on the {110}α plane suggested by the ledge mechanism but on other planes. [Copyright &y& Elsevier]

Interactions of calcium and phosphate ions with extracellular matrix (ECM) proteins are critical in the development of mineralized tissues such as tooth and bone. Recently, DNA has been used as a building block for materials that can mimic structural features of ECM due to DNA's base-pairing specificity, ease of functionalization and predictable self-assembly into nanoengineered structures. Here we describe the synthesis of DNA nanostructures functionalized with mineral-promoting peptides derived from ECM proteins present during mineralized tissue development, and their use as scaffolds that template the growth of hydroxyapatite in vitro and in vivo. Mineral promoting peptide sequences were conjugated to single stranded DNA using a one-step thiol-ene click chemistry reaction. The peptide-DNA conjugates were purified by anion exchange chromatography and their purity was characterized by gel electrophoresis and anion exchange chromatography. Peptide-DNA conjugates were designed to be complementary to single stranded regions of self-assembled 2D and 3D DNA nanostructures, thus placing the mineralizing peptides at specific locations within DNA scaffolds. Peptide-DNA hybrid nanostructures were then exposed to mineralizing conditions (solutions containing calcium and phosphate ions). Mineral formation was characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM) and Fourier Transform Infrared (FTIR) spectroscopy. Nanostructure degradation in vitro in 10% fetal bovine serum (FBS) was characterized by gel electrophoresis. Cytotoxicity was assessed in vitro using osteoblasts, and in vivo in a rat model. Peptide-DNA conjugates were synthesized with 30-60% yield; these were incorporated into DNA nanostructures through DNA sequence complementarity. Peptide-DNA nanostructures promoted site-specific mineralization. The type of mineral obtained was dependent on time, DNA nanostructure shape and on the amount of calcium and phosphate ions present in solution. Nanostructure degradation occurred between 3-14 days in 10% FBS, and these were not cytotoxic in vitro and in vivo. DNA nanostructures can be functionalized with mineral promoting peptides and they act as a platform to investigate guided mineralization. Peptide-DNA nanostructures control the growth of highly organized nanocrystalline hydroxyapatite, while maintaining cell viability. DNA nanostructures have the potential to develop into biomaterials used for mineralized tissue regeneration. [ABSTRACT FROM AUTHOR]

Characterization of the dynamic mechanical behavior of brain tissue is essential for understanding and simulating the mechanisms of traumatic brain injury (TBI). Changes in mechanical properties may also reflect changes in the brain due to aging or disease. In this study, we used magnetic resonance elastography (MRE) to measure the viscoelastic properties of ferret brain tissue in vivo. Three- dimensional (3D) displacement fields were acquired during wave propagation in the brain induced by harmonic excitation of the skull at 400 Hz, 600 Hz and 800 Hz. Shear waves with wavelengths in the order of millimeters were clearly visible in the displacement field, in strain fields, and in the curl of displacement field (which contains no contributions from longitudinal waves). Viscoelastic parameters (storage and loss moduli) governing dynamic shear deformation were estimated in gray and white matter for these excitation frequencies. To characterize the reproducibility of measurements, two ferrets were studied on three different dates each. Estimated viscoelastic properties of white matter in the ferret brain were generally similar to those of gray matter and consistent between animals and scan dates. In both tissue types G' increased from approximately 3 kPa at 400 Hz to 7 kPa at 800 Hz and G" increased from approximately 1 kPa at 400 Hz to 2 kPa at 800 Hz. These measurements of shear wave propagation in the ferret brain can be used to both parameterize and validate finite element models of brain biomechanics. [ABSTRACT FROM AUTHOR]

Abstract: Perfluorooctane sulfonate (PFOS) is the latest chemical categorized as persistent organic pollutants (POPs). PFOS appears in the environmental water and tap water in ngL−1 level. The process of adsorption has been identified as an effective technique to eliminate PFOS in water. Three non-ion-exchange polymers (DowV493, DowL493 and AmbXAD4), two ion-exchange polymers (DowMarathonA and AmbIRA400) and one granular activated carbon (GAC) (Filtersorb400) were tested with regard to their sorption kinetics and isotherms at low PFOS concentrations (100–1000ngL−1 equilibrium concentrations). The sorption capacities at 1μgL−1 equilibrium concentration decreased in the following order: Ion-exchange polymers>non-ion-exchange polymers>GAC, but at further low equilibrium concentration (100ngL−1) non-ion-exchange polymers showed higher adsorption capacity than other adsorbents. In the case of sorption kinetics, GAC and ion-exchange polymers reached the equilibrium concentration within 4h and AmbXAD4 within 10h. DowV493 and DowL493 took more than 80h to reach equilibrium concentration. AmbIRA400 was identified as the best filter material to eliminate PFOS at equilibrium concentration>1000ngL−1. Considering both adsorption isotherms and adsorption kinetics, AmbXAD4 and DowMarathonA were recommended to eliminate PFOS at ngL−1 equilibrium concentration. [Copyright &y& Elsevier]