Aim
The aim of this study was to investigate the effects of a self‐assembling peptide (SAP) nanofibre hydrogel on healing of surgical periodontal defects in rats.
Materials and Methods
In vitro ...interactions between rat periodontal ligament (PDL) cells and SAP hydrogel (2.5% RADA16) were assessed by cell proliferation assays. In vivo, maxillary first molars of 45 Wistar rats were extracted and after healing, bilateral periodontal defects were surgically created mesially in second molars. Defects were treated with RADA16, Matrigel, or left unfilled. After 2 and 4 weeks, defect healing was evaluated by microcomputed tomography, histological and immunohistochemical analyses.
Results
Periodontal ligament cells grown on RADA16 showed an gradual increase in proliferation up to 72 h. At 4 weeks post surgery, the bone volume fraction and trabecular thickness of defect areas in the RADA16 group were significantly greater than those in other groups. Histologically, enhanced new bone formation was observed in the RADA16 group. At 4 weeks, PDL‐like collagen bundles ran oblique to the root surface in the RADA16 group. Expression levels of PCNA‐positive cells, vascular endothelial growth factor and osteopontin in the RADA16 group were significantly greater than those in other groups.
Conclusions
Within the limitations of the study, application of the SAP hydrogel promoted healing of surgical periodontal defects by enhancing cell recruitment and possibly angiogenesis.
We have previously reported that repeated treatment of human periodontal ligament cells and murine pre-osteoblast MC3T3-E1 cells with transforming growth factor-beta 1 (TGF-β1) inhibited their ...osteoblastic differentiation because of decreased insulin-like growth factor-1 (IGF-1) secretion. We also found that IGF-1/PI3K signaling plays an important role in osteoblast differentiation induced by TGF-β1 treatment; however, the downstream signaling controlling this remains unknown. The aim of this current study is to investigate whether Akt activation is required for osteoblast differentiation.
MC3T3-E1 cells were cultured in osteoblast differentiation medium (OBM) with or without 0.1 ng/mL TGF-β1. OBM containing TGF-β1 was changed every 12 h to provide repeated TGF-β1 administration. MC3T3-E1 cells were infected with retroviral vectors expressing constitutively active (CA) or dominant-negative (DN)-Akt. Alkaline phosphatase (ALP) activity and osteoblastic marker mRNA levels were substantially decreased by repeated TGF-β1 treatment compared with a single TGF-β1 treatment. However, expression of CA-Akt restored ALP activity following TGF-β1 treatment. Surprisingly, ALP activity increased following multiple TGF-β1 treatments as the number of administrations of TGF-β1 increased. Activation of Akt significantly enhanced expression of osteocalcin, but TGF-β1 treatment inhibited this. Mineralization of MC3T3-E1 cells was markedly enhanced by CA-Akt expression under all medium conditions. Exogenous IGF-1 restored the down-regulation of osteoblast-related gene expression by repeated TGF-β1 administration. However, in cells expressing DN-Akt, these levels remained inhibited regardless of IGF-1 treatment. These findings indicate that Akt activation is required for the early phase of osteoblast differentiation of MC3T3-E1 cells induced by TGF-β1. However, Akt activation is insufficient to reverse the inhibitory effects of TGF-β1 in the late stages of osteoblast differentiation.
TGF-β1 could be an inducer or an inhibitor of osteoblastic differentiation of MC3T3-E1 cells depending on the state of Akt phosphorylation. Our results indicate that Akt is the molecular switch for TGF-β1-induced osteoblastic differentiation of MC3T3-E1 cells.
Scandium is being explored as an alloying element for aluminium alloys, which are gaining importance as high-performance lightweight structural alloys in the transportation industry. Sc-rich ScAlN ...thin films show strong piezoelectricity and can be fabricated on a hard substrate for use as wideband surface acoustic wave filters in next-generation wireless mobile communication systems. However, the use of ScAlN thin films in microelectromechanical system devices is limited by the high cost of metallic Sc, which is due to the difficulty in smelting of this material. Here, we propose a novel microwave irradiation process for producing Al-Sc alloys, with Mg ions as a reducing agent. Although scandium oxide is thermodynamically stable, intermetallic Al
Sc is obtained in high yield (69.8%) via a low-temperature (660 °C) reduction reaction under microwave irradiation. Optical spectroscopy results and thermodynamic considerations suggest a non-thermal equilibrium reaction with the univalent magnesium ions excited by microwave irradiation.
Objective High adherence to medications and accurate handling of inhaler devices are important for asthma management. However, few reports to date have simultaneously evaluated adherence and handling ...errors. We therefore investigated the adherence to inhaled corticosteroid (ICS) and inhaler handling errors in the same patients in cooperation with pharmacists. Methods Data were derived from a survey of physicians and pharmacists treating asthma patients who visited participating hospitals and pharmacies from July 2012 to January 2013. The patients were evaluated for asthma control using the Asthma Control Test (ACT) and for inhaler handling errors using checklists. ICS adherence was evaluated based on pharmaceutical records. Results Adherence among participants (n=290) was 33.3% (mean), and the percentage of inhaler handling errors was 20.0% (mean). Total inhalation times in the high-adherence group were fewer than those in the low-adherence group. In a comparison by device, adherence to pressurized metered dose inhalers was significantly lower than that to Diskus® inhalers, presumably attributable to the total number of inhalations per day. Adherence, handling errors, and total number of inhalations per day were significantly different between the asthma-controlled group and the uncontrolled group. A multivariate analysis showed that adherence and handling errors were independent factors contributing to asthma control. Conclusion Our data indicated that both adherence to ICS and device handling errors contributed to asthma control in this population.
Magnesium (Mg) is a lightweight metal with applications in transportation and sustainable battery technologies, but its current production through ore reduction using the conventional Pidgeon process ...emits large amounts of CO
and particulate matter (PM2.5). In this work, a novel Pidgeon process driven by microwaves has been developed to produce Mg metal with less energy consumption and no direct CO
emission. An antenna structure consisting of dolomite as the Mg source and a ferrosilicon antenna as the reducing material was used to confine microwave energy emitted from a magnetron installed in a microwave oven to produce a practical amount of pure Mg metal. This microwave Pidgeon process with an antenna configuration made it possible to produce Mg with an energy consumption of 58.6 GJ/t, corresponding to a 68.6% reduction when compared to the conventional method.
Objective Whether or not depression affects the control or severity of asthma is unclear. We performed a cluster analysis of asthma patients with depressive symptoms to clarify their characteristics. ...Methods Multiple medical institutions in Niigata Prefecture, Japan, were surveyed in 2014. We recorded the age, disease duration, body mass index (BMI), medications, and surveyed asthma control status and severity, as well as depressive symptoms and adherence to treatment using questionnaires. A hierarchical cluster analysis was performed on the group of patients assessed as having depression. Results Of 2,273 patients, 128 were assessed as being positive for depressive symptoms DS(+). Thirty-three were excluded because of missing data, and the remaining 95 DS+ patients were classified into 3 clusters (A, B, and C). The patients in cluster A (n=19) were elderly, had severe, poorly controlled asthma, and demonstrated possible adherence barriers; those in cluster B (n=26) were elderly with a low BMI and had no significant adherence barriers but had severe, poorly controlled asthma; and those in cluster C (n=50) were younger, with a high BMI, no significant adherence barriers, well-controlled asthma, and few were severely affected. The scores for depressive symptoms were not significantly different between clusters. Conclusion About half of the patients in the DS+ group had severe, poorly controlled asthma, and these clusters were able to be distinguished by their Adherence Starts with Knowledge (ASK)-12 score, which reflects adherence barriers. The control status and severity of asthma may also be related to the age, disease duration, and BMI in the DS+ group.
Aluminum and aluminum alloys are light materials with some of the preferences such as lightweight, high specific strength, good elasticity, and good workability that play an important role in today's ...modern and industrial world. The economic loss and environmental and safety problems are also the most concerning aspects of these materials. As a result, numerous studies are performed by the researchers to improve the overall environment throughout the materials world. That is why, in this study, the surface morphology and corrosion behavior of pure aluminum and its alloys, such as 7S10 and 7003H, were investigated in aqueous sulfuric acid medium through immersion process at different temperatures. Open‐circuit potential and potentiodynamic polarization techniques were used to evaluate the resistance to corrosion of pure aluminum and its alloys 7S10 and 7003H. The current density increased with increasing temperature in the case of the alloys, and pure aluminum showed the highest corrosion resistance properties. The surface roughness measurement was performed using atomic force microscope to find out the amount of roughness of the used materials before and after the immersion process. Surface roughness was higher on the alloys than in pure Al, which indicates that less corrosion was formed in pure Al than in the alloys. The surface morphology analysis was also carried out using scanning electron microscopic data. The results revealed that the alloy 7003H undergoes more corrosion than pure aluminum and 7S10 in sulfuric acid medium, which clearly indicates that pure aluminum has higher corrosion resistance than the alloys 7S10 and 7003H. The corrosion rate of the test materials decreased with increasing immersion time.
The surface morphology and corrosion behavior of pure aluminum and its alloys such as 7S10 and 7003H were investigated in aqueous sulfuric acid at different temperatures with the help of open circuit potential and potentiodynamic polarizations. The microscopic images, atomic force microscope images, and scanning electron microscopic data were also analyzed.
Sublingual immunotherapy (SLIT) has received attention as a method for allergen immunotherapy. However, the mechanism of SLIT has not yet been fully investigated. Therefore, we evaluated the effects ...of SLIT in a murine asthma model, sensitized by intranasal administration of house dust mite (HDM) extracts.
Female BALB/c mice were intranasally exposed to HDM for either 3 or 5 weeks (5 consecutive days per week). Mice were administered either low-dose (0.5 mg/day) or high-dose (5 mg/day) sublingual HDM extracts for 2 weeks, followed by an additional week of intranasal exposure. Airway hyperresponsiveness (AHR), bronchoalveolar lavage fluid (BALF) cell count, cytokine levels in the BALF and lymph node cell culture supernatants, and allergen-specific antibodies were measured. Lung histology was also investigated.
In mice sensitized for 5 weeks, high-dose SLIT ameliorated AHR, airway eosinophilia and goblet cell metaplasia. In mice sensitized for 3 weeks, even low dose SLIT ameliorated AHR and airway eosinophilia. Th2 cytokine levels in culture supernatants of submandibular lymph node cells in high-dose SLIT mice decreased, whereas IL-10 levels increased. Total IgA in BALF increased in mice sensitized for 3 or 5 weeks, and high-dose SLIT also increased allergen-specific IgG2a in mice sensitized for 5 weeks.
These data suggest that earlier induction of SLIT in HDM-sensitized mice provides superior suppression of AHR and goblet cell metaplasia. The modulation of allergen specific IgG2a and local IgA might play a role in the amelioration of AHR and airway inflammation.
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