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A linear one-dimensional dissipative model is proposed and applied in obtaining numerical simulation results for coupled double quantum dot cells, for single-electron transport dynamics on each cell. Field coupling between cells is modeled simply from a matrix of mutual capacitances. Bistability with only one excess electron on each cell, in a pair of coupled double-dot cells, is demonstrated. Behavior prediction and performance evaluation, for applications such as computational system implementation, are made possible. It is understood from the simulations that balanced dissipation rates are essential for the implementation of optimized single-electron devices, with short settling times. [ABSTRACT FROM AUTHOR]

The present study aimed to identify students' perceptions of endodontic treatment at a Brazilian university through a survey, which analysed student profiles and their difficulties in 2016. One hundred and two students who had experienced endodontic, laboratory or clinical procedures answered a survey based on their experiences, regarding their perceptions, experience and self‐confidence levels. Results demonstrated that there was no significant difficulty among students regarding anaesthesia, rubber dam use, chamber access, working length determination, instrumentation, root filling and temporary restoration procedures during endodontic treatment. However, problems were observed regarding radiographic examination (mainly in separating root canals) and the choice of intracanal medication. The present study also raised a question regarding dental education: how can endodontic education be improved by addressing students' perceived difficulties? Evaluating the major student difficulties during root canal therapy can help the improvement of teaching strategies during preclinical and clinical teaching. [ABSTRACT FROM AUTHOR]

Dental pulp is a specialized tissue able to respond to infectious processes. Nevertheless, infection progress and root canal colonization trigger an immune-inflammatory response in tooth-surrounding tissues, leading to apical periodontitis and bone tissue destruction, further contributing to tooth loss. In order to shed some light on the effects of IL-4 on periradicular pathology development modulation, microtomographic, histological and proteomic analyses were performed using 60 mice, 30 wild type and 30 IL-4 - / - . For that, 5 animals were used for microtomographic and histological analysis, and another 5 for proteomic analysis for 0, 7 and 21 days with/without pulp exposure. The periapical lesions were established in WT and IL-4 - / - mice without statistical differences in their volume, and the value of p < 0.05 was adopted as significant in microtomographic and histological analyses. Regarding histological analysis, IL-4 - / - mice show aggravation of pulp inflammation compared to WT. By using proteomic analysis, we have identified 32 proteins with increased abundance and 218 proteins with decreased abundance in WT animals after 21 days of pulp exposure, compared to IL-4 - / - animals. However, IL-4 - / - mice demonstrated faster development of apical periodontitis. These animals developed a compensatory mechanism to overcome IL-4 absence, putatively based on the identification of upregulated proteins related to immune system signaling pathways. Significance: IL-4 might play a protective role in diseases involving bone destruction and its activity may contribute to host protection, mainly due to its antiosteoclastogenic action., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Diabetes mellitus (DM) is a metabolic disorder that results in the impairment of the metabolism of carbohydrates, proteins and lipids. It can give rise to various complications, mainly caused by chronic exposure of cells to high glucose concentrations, including changes in the immune response processes. The aim of this study was to verify the chemokine and cytokines production profile in the presence of different glucose concentrations and infection/inflammatory stimuli. To this end, cell viability and the production of chemokines, cytokines and nitric oxide (NO) were analyzed in RAW 264.7 cell culture. Results demonstrated that there was no change in cell viability after 6, 24 and 72 h. Different stimuli were unable to modify the monocyte chemoattractant protein (MCP)-1 and tumor necrosis factor (TNF)-α production. Groups stimulated with lipopolysaccharides (LPS) and LPS and recombinant interferon (rIFN)-γ down-regulated interleukin (IL)-1α, IL-10 and IL-12 and up-regulated IL-6 production. NO production maintained a pattern of increase, according to the increase in glucose concentrations, reaching its peak at 72 h. In summary, the results demonstrated that high glucose concentrations alone may be sufficient to alter the in vitro mediators' production of RAW 264.7 cells., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Bone resorption is an important factor in bone homeostasis and imbalance can cause several diseases. In osteoimmunology, IL-4 has been described as an important factor in promoting M2 macrophage profile. In order to shed some light on the effect of IL-4 on osteoclast precursors in the presence of RANKL, cytokines and nitric oxide (NO) production and the proteomic profile were analyzed. The presence of IL-4 in in vitro osteoclastogenesis provides production of TNF-α, IL-1α, IL-1β, IL-10 and IL-12 at basal cell levels. Regarding NO production, IL-4 was sufficient to increase the basal NO levels. Proteomic analyses identified 877 global proteins. IL-4 in in vitro RANKL-mediated osteoclastogenesis leads to the expression of 118 proteins. The presence of rIL-4 in in vitro rRANKL-mediated-osteoclastogenesis downregulated this process. However, the proteomics findings in the osteoclastogenesis demonstrated a much greater effect on osteoclast precursor cells than on RANKL-differentiated osteoclasts. These results suggest that the main effect of IL-4 in pre-osteoclast cells leads to a M2 macrophage activation, and this probably contributed to a reduction in osteoclastogenesis when both stimuli were used. This study noticed that IL-4 plays an important regulatory role in bone homeostasis due to its suppressive potential of precursor osteoclast cells., (Copyright © 2015 Elsevier B.V. All rights reserved.)