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Purpose: Stem cell therapy is becoming a potent strategy to shorten the consolidation time and reduce potential complications during distraction osteogenesis (DO). However, the conventional local injection or scaffold-based delivery of bone marrow mesenchymal stem cell (BMSC) suspension deprives the cells of their endogenous extracellular matrix, which might dampen cell differentiation and tissue regeneration after implantation. Therefore, in our study, a BMSC sheet was established and was then minced into fragments and loaded onto a hydroxyapatite (HA) scaffold for grafting.Materials and Methods: The purified and characterized BMSCs were grown into a cell sheet, and bone formation and mineralization capacity, as well as the cell sheet composition, were analyzed. Afterward, the in vivo osteogenic ability of cell sheet fragments (CSFs) was evaluated in immunocompromised mouse and rabbit models of DO.Results: The BMSC sheet exhibited higher alkaline phosphatase activity than osteogenic cell suspension cultures. Alkaline phosphatase activity and mineral particles in the cell sheet increased further after osteogenic induction. Moreover, calcium and phosphorus were present only in the osteogenic cell sheet, along with the common elements carbon, oxygen, chlorine, sodium, and sulfur, as indicated by x-ray photoelectron spectroscopy analysis. In a mouse model, the CSF-HA complex was injected subcutaneously. Micro-computed tomography analysis showed that the osteogenic CSF-HA complex led to a considerably higher bone volume than the BMSC-HA or CSF-HA complex. The osteogenic CSF-HA specimens showed increased angiogenesis and deposition of type I collagen compared with the non-osteogenic CSF-HA or BMSC-HA specimens. Moreover, the osteogenic CSF-HA markedly improved bone consolidation and increased bone mass in DO rabbits.Conclusions: Collectively, the incorporation of osteogenic BMSC sheets into HA particles greatly promoted bone regeneration, which offers therapeutic alternatives for DO. [ABSTRACT FROM AUTHOR]

Anodic polarization treatment was used to investigate microbiologically influenced corrosion (MIC) behavior of 316 L -Cu stainless steel (SS) against marine Pseudomonas aeruginosa using electrochemical tests and morphology observation techniques. The results indicated that anodic polarization treatment endowed 316 L -Cu SS with a decreased corrosion current and increased pitting potential in comparison with conventional 316 L SS and 316 L -Cu SS incubated in a biotic medium. The surface morphology observations combined with XPS analysis found that 316 L -Cu SS effectively inhibited bacterial reproduction and promoted the formation of a dense protective extracellular polymeric substance (EPS)-Fe membrane, leading to less susceptibility to pitting corrosion than 316 L SS. [Display omitted] • Anodic polarization treatment (APT) on MIC behavior of stainless steel is studied. • APT regulates the attachment of Pseudomonas aeruginosa with negative charge. • APT promotes the formation of EPS-Fe membrane with protective effect. • Cu-bearing SS combined with EPS-Fe membrane can continuously inhibit MIC. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to reconstruct alveolar crest at home position using distraction osteogenesis (DO) with a personalized curvilinear distractor designed through computer-aided technology. Study design: Five adult dogs were recruited and the maxillary alveolar bone from the first incisor to the first premolar was excised. The dentoalveolar segment adjacent to the defect was osteotomized as a bone transport disk. After 8 weeks of consolidation, the dogs were humanely killed, and the regenerated bone was analyzed. Results: The DO was successful in the experimental group. The radiographs and histology both verified new bone bridging distraction gap. However, the newly formed bone was located more internally and was not in original position. Conclusions: The proposed method to reconstruct alveolar crest at home position is improper. The key point was how to maintain the distraction space and hold it at the home position. The barrier membrane technique may be used together with DO to resolve the problem. [Copyright &y& Elsevier]

Purpose: To improve the reconstructive surgical outcome of a discontinuous mandibular defect, we used reverse engineering (RE), computer-aided design (CAD), and rapid prototyping (RP) technique to fabricate customized mandibular trays to precisely restore the mandibular defects. Autogenous bone grafting was also used to restore the bony continuity for occlusion rehabilitation. Patients and Methods: Six patients who had undergone block resection of the mandible underwent reconstruction using a custom titanium tray combining autogenous iliac grafts. The custom titanium tray was made using a RE/CAD/RP technique. A virtual 3-dimensional model was obtained by spiral computed tomography scanning. The opposite side of the mandible was mirrored to cover the defect area to restore excellent facial symmetry. A bone grafting tray was designed from the mirrored image and manufactured using RP processing and casting. The mandibular defects were restored using the trays in combination of autologous iliac grafting. An implant denture was made for 1 of the 6 patients at 24 weeks postoperatively for occlusion rehabilitation. Results: The trays fabricated using this technique fit well in all 6 patients. The reconstructive procedures were easy and time saving. Satisfactory facial symmetry was restored. No severe complications occurred in the 5 patients without occlusion rehabilitation during a mean 50-month follow-up period. The reconstruction in the patient with occlusion lasted for only 1 year and failed eventually because of bone resorption and infection. Conclusions: Mandibular reconstruction was facilitated using the RE/CAD/RP technique. Satisfactory esthetic results were achieved. However, the rigidity of the cast tray could cause severe stress shielding to the grafts, which could lead to disuse atrophy. Therefore, some modification is needed for functional reconstruction. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the present study was to evaluate the efficiency of fixation with a novel (bulge core type system) rigid internal fixation system. Materials and Methods: Mandibular linear fractures were created artificially in dogs and fixed using a bulge core type system or a miniplate system in vitro. A 3-point load cell was used to contrast the fixation strength of the 2 systems in vitro. Histologic sections were used to analyze the healing of mandibular linear fractures and to contrast the efficiency of fixation of the 2 systems in vivo. Tetracycline-fluorescein staining technology was used to evaluate the bone healing speed in the mandibular fracture lines during bone healing. Results: In vitro, the 3-point load cell showed that the fixation strength of the bulge core type system was greater than that of the miniplate system (P < .05). In vivo, the histologic sections and tetracycline-fluorescein staining showed that greater and quicker bony healing occurred using the bulge core type system (P < .05) and that the efficiency of fixation of the 2 systems was similar. Conclusion: Our results have shown that the bulge core type system can provide sufficient strength for mandibular linear fracture healing. [Copyright &y& Elsevier]

Abstract: A new internal distraction device, comprising a square-bodied bow, a transport plate, a traction mechanism, and two stabilisers, was developed to allow transportation of bone around an arc. Eight adult goats were studied. A curved mandibulectomy 3cm long was made on the mandibular angle. The distractor was implanted to restore the defect. The bone was distracted at a rate of 1mm per day after a 5-day latent period. Distraction lasted 25 to 32 days. Curvilinear distraction was successful in six of the eight goats. After consolidation periods of four or eight weeks, smooth curved bone masses were restored in the distracted areas. Radiographically, there was considerable bone density in the distraction area and opaque columns streamed in the direction of distraction. Histological examination showed membranous bony regeneration in the restored bone. These results suggest that restoration of curved bone defects using the new internal transport distraction device was feasible in goats. [Copyright &y& Elsevier]

Summary: Temporomandibular joint (TMJ) ankylosis is a disease that severely affects the human health. Although it is well known that trauma is the most common cause of TMJ ankylosis, the mechanisms by which the traumatic TMJ ankylosis develops are unclear. The existing hypothesis is not convincing in explaining the genesis of traumatic TMJ ankylosis. We make a hypothesis that the distraction osteogenesis (DO) of the lateral pterygoid muscle combining with the dislocated and damaged disc is an important factor in genesis of traumatic TMJ ankylosis. If this hypothesis is verified, it will be helpful for the prevention of traumatic TMJ ankylosis and change the principle of management of sagittal fracture of mandibular condyle (SFMC). [Copyright &y& Elsevier]

Objective Osteosarcoma is an aggressive malignant neoplasm, which commonly afflicts patients of 20–30 years of age, and its morbidity has increased markedly in recent years. Certain genes and signal pathways have been identified to exert key roles in osteosarcoma progression. Here, we set out to characterize in more detail of the role of HIF-1/AKT/Cyclin D1 pathway in the progression of osteosarcoma. Methods Immunohistochemistry, western blot and qPCR were used to test the protein or mRNA levels of HIF-1 in osteosarcoma tissues or adjacent nontumor tissues. MTT, clone formation, wound healing, Transwell, in vivo tumorigenesis, flow cytometry and western blot analysis were used to determine cell proliferation, clone formation ability, migration, invasion, tumorigenesis, and cell apoptosis in MG63 and U2OS cells, respectively. Immunoprecipitation and immunofluorescence assays were performed to investigate the protein-protein interaction between HIF-1α and proteins related to signal pathways. Results HIF-1 was overexpressed in osteosarcoma tissues and cell lines, which promoted cell proliferation, clone formation, migration, invasion and inhibited cell apoptosis. Results also demonstrated that HIF-1 combined with AKT, and there might be a positive loop between the two proteins of HIF-1 and AKT, then the protein-protein interaction up-regulated the expression of Cyclin D1 in protein level, but not mRNA level, made Cyclin D1 protein more stable, triggered cell proliferation, clone formation, tumorigenesis, but inhibited cell apoptosis. Conclusions The present study showed that HIF-1 modulated Cyclin D1 expression might through shaping a positive loop with AKT proteins. Additionally, HIF-1α promoted the tumor cells growth, migration and invasion in osteosarcoma through the activation of the AKT/Cyclin D1 signal cascade. We proposed that HIF-1 could be served as a marker for distinguishing osteosarcoma and an effective therapeutic target for osteosarcoma. [ABSTRACT FROM AUTHOR]

• This paper proposed a novel automatic calibration method which can automatically deduct various baseline of Campbelling mode and obtain neutron yield in real time. • The automatic calibration method was verified with the experimental data on EAST. It is suitable for different experiment conditions, and the Relative Root Mean Square Error values of automatic calibration results were obviously lower than that of offline fixed calibration results. To satisfy the wide-range requirement for the fission chamber-based neutron flux monitoring (NFM) system on experimental advanced superconducting tokamak (EAST), the pulse-counting and Campbell modes were combined to expand the measurement range. However, to obtain the neutron yields, the results of the Campbell mode should first be converted into neutron count rates via linear calibration. During the plasma experiment, the non-neutron backgrounds vary with respect to different experimental conditions, which leads to a baseline dynamic change in the Campbell mode. In future research, NFM system need provide real-time feedback parameters regarding the operational status of the fusion device. Therefore, an automatic calibration method was developed to automatically deduct various baselines of the Campbell mode and obtain the neutron yields in real time. This method continuously updates the average value of each sub-interval (multiple sub-intervals are set in the calibration region) using a linear superposition averaging method. In addition, to optimize the dual-mode switching threshold, ensure the calibration region and define the upper limit of Campbell mode, a simulated neutron signal generator was designed and applied. The switching threshold of the dual modes was set to 400 kcps, the calibration region of the Campbell mode was selected as 50–500 kcps, and the upper limit of the equivalent count rate in the Campbell mode reached to 10 8 cps with a relative error of<4%. Finally, the automatic calibration method was tested using experimental data from the NFM system on EAST. The automatic calibration results basically overlapped with the reference results and superior to the offline fixed calibration results. Under different experimental conditions, the relative root mean square error (RRMSE) values of the automatic calibration results were lower than those of the offline fixed calibration results. Therefore, the proposed automatic calibration method is accurate and reliable, and can satisfy the real-time measurement requirements of wide-range NFM system. [ABSTRACT FROM AUTHOR]

Neuraminidase (NA) is one of the particular potential targets for novel antiviral therapy. In this work, a series of neuraminidase inhibitors with the cyclohexene scaffold were studied based upon the combination of 3D-QSAR, molecular docking, and molecular dynamics techniques. The results indicate that the built 3D-QSAR models yield reliable statistical information: the correlation coefficient (r 2 ) and cross-validation coefficient (q 2 ) of CoMFA (comparative molecular field analysis) are 0.992 and 0.819; the r 2 and q 2 of CoMSIA (comparative molecular similarity analysis) are 0.992 and 0.863, respectively. Molecular docking and MD simulations were conducted to confirm the detailed binding mode of enzyme-inhibitor system. The new NA inhibitors had been designed, synthesized, and their inhibitory activities against group-1 neuraminidase were determined. One agent displayed excellent neuraminidase inhibition, with IC 50 value of 39.6 μM against NA, while IC 50 value for oseltamivir is 61.1 μM. This compound may be further investigated for the treatment of infection by the new type influenza virus. [ABSTRACT FROM AUTHOR]

• Digestion products of shrimp-TM yielded many peptides matched T/B cell epitopes. • Digestion products of shrimp-TM in SGF profile showed a significant difference from others. • Peptides of shrimp-TM matched more T/B cell epitopes than those of fish-TM and clam-TM. • Core regions of shrimp-TM matched T/B cell epitopes are distributed along the entire chain. • A differentiating peptide of shrimp-TM (72–88) could be as a potential peptide marker. Tropomyosin (TM) is a major shellfish allergen and a minor fish allergen. Different digestion profiles affect potential allergen anaphylaxis of protein. In this study, released peptides of fish-TM, shrimp-TM, and clam-TM by in vitro digestion of simulated gastric fluid (SGF), simulated intestinal fluid (SIF), and gastrointestinal (GI) were analyzed using sequential windowed acquisition of all theoretical fragment ion mass spectra (SWATH-MS) based proteomics. Results showed that digestion products of shrimp-TM yielded a lot of peptides matched T/B cell epitopes while core regions matched epitopes were distributed along the entire chain. Pepsin or trypsin-based digestion products of shrimp-TM presented many more peptides matched T/B cell epitopes compared with those of fish-TM and clam-TM. Besides, a differentiating peptide of VEKDKALSNAEGEVAAL (72–88) overlapped T/B cell epitopes could be used as a candidate peptide marker to identify tropomyosin allergen. These findings would supply new insight into the different allergenicity of tropomyosin. [ABSTRACT FROM AUTHOR]