Macrophage M1 polarization mediated via the IL-6/STAT3 pathway contributes to apical periodontitis induced by Porphyromonas gingivalis

Objective: To investigate the involvement of IL-6/STAT3 signaling pathway activation in macrophage polarization and bone destruction related to apical periodontitis (AP) stimulated by Porphyromonas gingivalis. Methodology: Macrophage polarization, IL-6/STAT3 expression, and the presence of P. gingivalis were detected in human AP tissues via RT-qPCR, western blotting, and immunohistochemistry staining. Murine bone marrow derived macrophages were isolated and cultured with P. gingivalis W83 in vitro, and levels of macrophage IL-6 expression, STAT3 phosphorylation, and macrophage polarization with or without the selective STAT3 phosphorylation inhibitor Stattic (5 μM) were detected via ELISA, western blotting, RT-qPCR, and flow cytometry, respectively. P. gingivalis-induced murine AP models were constructed, and bone destruction and macrophage polarization in the apical region were evaluated. Transwell co-culture systems were used to investigate the effects of macrophages infected with P. gingivalis on osteogenesis and osteoclastogenesis. Results: P. gingivalis was detected in human AP tissues that highly expressed IL-6/STAT3, and the M1 subtype of macrophages was more abundant in these tissues. P. gingivalis infection induced IL-6 expression, STAT3 phosphorylation, and M1 polarization of macrophages, while 5 μM of Stattic partially abolished these activation effects. Systemic STAT3 blockade via oral administration of Stattic at a dose of 25 mg kg-1 alleviated murine periapical bone resorption and apical infiltration of M1 macrophages induced by P. gingivalis infection in vivo. Furthermore, macrophages infected with P. gingivalis promoted bone destruction via secretion of IL-6, TNF-α, and RANKL, which hinder pre-osteoblast expression of Runx2 and accelerate pre-osteoclast expression of NFAT2. Conclusions:The activation of IL-6/STAT3 signaling pathway is involved in mediating macrophages M1 polarization in the P. gingivalis induced apical inflammatory context and may also be intimately involved in the bone loss caused by P. gingivalis infection, directing the M1 macrophage infiltration during the progression of AP.&nbsp

The Airlines’ Recent Experience Under the Railway Labor Act

Silky-feather has been selected and fixed in some breeds due to its unique appearance. This phenotype is caused by a single recessive gene (hookless, h). Here we map the silky-feather locus to chromosome 3 by linkage analysis and subsequently fine-map it to an 18.9 kb interval using the identical by descent (IBD) method. Further analysis reveals that a C to G transversion located upstream of the prenyl (decaprenyl) diphosphate synthase, subunit 2 (PDSS2) gene is causing silky-feather. All silky-feather birds are homozygous for the G allele. The silky-feather mutation significantly decreases the expression of PDSS2 during feather development in vivo. Consistent with the regulatory effect, the C to G transversion is shown to remarkably reduce PDSS2 promoter activity in vitro. We report a new example of feather structure variation associated with a spontaneous mutation and provide new insight into the PDSS2 function

Deep Learning Based Steel Pipe Weld Defect Detection

Steel pipes are widely used in high-risk and high-pressure scenarios such as oil, chemical, natural gas, shale gas, etc. If there is some defect in steel pipes, it will lead to serious adverse consequences. Applying object detection in the field of deep learning to pipe weld defect detection and identification can effectively improve inspection efficiency and promote the development of industrial automation. Most predecessors used traditional computer vision methods applied to detect defects of steel pipe weld seams. However, traditional computer vision methods rely on prior knowledge and can only detect defects with a single feature, so it is difficult to complete the task of multi-defect classification, while deep learning is end-to-end. In this paper, the state-of-the-art single-stage object detection algorithm YOLOv5 is proposed to be applied to the field of steel pipe weld defect detection and compared with the two-stage representative object detection algorithm Faster R-CNN. The experimental results show that applying YOLOv5 to steel pipe weld defect detection can greatly improve the accuracy, complete the multi-classification task, and meet the criteria of real-time detection

The remaining dentin thickness investigation of the attempt to remove broken instrument from mesiobuccal canals of maxillary first molars with virtual simulation technique

Background: To investigate differences in the estimated minimum remaining dentin thickness (RDT) between periapical radiographs using the paralleling and parallax technique, after simulated removal of broken instrument from the mesiobuccal (MB) canal of maxillary first molar in virtual simulation model. The 3D measurement was taken as the standard for comparison. Methods: Thirty-six maxillary first molars were scanned by micro-CT and reconstructed as 3-dimensional (3D) model. A virtual fragment of an instrument was created within the MB canal in software. Removal of the broken instrument was simulated in both the 3D and 2D dataset. Then, the models of all specimens were submitted to 2D and 3D measurements for the lowest (RDT) value in each. Differences in the values between the paralleling and parallax radiographic technique and the 3D-RDT value were analyzed with two-way Analysis of Variance. The Intra-class Correlation Coefficient (ICC) was used to assess consistency of the RDT measurements between the two periapical radiographic and techniques and 3D analysis. Results: There was significant difference between RDT value obtained from the paralleling technique and 3D-RDT. There were no differences between RDT obtained from parallax (angled) technique and 3D-RDT. The ICC of RDT values between paralleling technique and 3D measurement were lower than 0.75. ICC between angled radiographs and 3D technique was close to 0.75. The optimal horizontal angle for the parallax technique was about 21°. Conclusions: The virtual simulation technique can provide valuable insight into the benefit/risk analysis before removal of a broken instrument. Parallel radiographs overestimate the actual remain dentin thickness in mesiobuccal canals of maxillary first molars, whereas the parallel technique would give a closer estimate to the actual thickness at a projection angle of about 21°.Dentistry, Faculty ofOral Biological and Medical Sciences (OBMS), Department ofOther UBCNon UBCReviewedFacult

Shaping outcome of ProTaper NEXT for root canal preparation in mandibular incisors: a micro-CT study

Abstract Background Relatively high incidence of single canals with oval or round shape were observed in human mandibular incisors. In order to investigate the influence of the root canal morphology on root canal preparation, the shaping outcome of ProTaper NEXT in oval and round canals of mandibular incisors were evaluated by using micro-computed tomography (micro-CT) analysis. Methods This experiment was approved by the School Medical Ethics Committee. The sample size calculation was conducted using G*Power software. Intact mandibular incisors with a single canal were selected. Oval canals (2  0.05). In the coronal two thirds of the canal, the post-operative structure model index (SMI), form factor and roundness were significantly increased, while the AR was significantly decreased in both groups (P < 0.05). In addition, in the coronal two thirds, significantly more UCW and higher UCWΔ% was observed in oval canal group (P < 0.05). Furthermore, UCW correlated very strongly to canal major diameter (0.924) and initial volume (0.938), and strongly to canal form factor (− 0.724), minor diameter (0.799) and canal area (0.882). Proximal dentin wall was associated with significantly thinner pre-operative dentin thickness and higher amount of dentin removal after root canal preparation in both oval and round canal groups. Conclusions (1) Both types of canals were more conical after root canal preparation, but oval root canals tend to leave more UCW area than round canals in the coronal two thirds of mandibular incisors, which contributes to the challenge for endodontic infection control. (2) Root canal preparation usually results in excessive dentin removal in the proximal dentin wall comparing with buccal and lingual walls in both types of canals of mandibular incisors

Nondestructive in situ monitoring of pea seeds germination using optical coherence tomography.

Seed germination and uniform plant stand in the field are the most critical crop growth stages determining the final yield. Pea (Pisum sativum L.) seeds production is often hampered due to the seed dormancy caused by the hard seed coat. Such effect is mainly attributed to poor or uneven germination and unsynchronised seedling emergence. Understanding the time course of water intake and several critical germination indicators can reveal many features of seed germination such as rate and uniformity. This paper used optical coherence tomography (OCT), a noninvasive and cross-sectional imaging technique, to monitor the inner structural changes throughout the germination process. A sequence of cross-sectional OCT images of pea (P. sativum L.) seeds, together with additional microscopic optical images, was recorded continuously and in situ for over 40 h. OCT and microscopic images revealed the changes in the internal structure and the external shape of the pea seeds during germination, respectively. It was found that the cross-sectional OCT images helped to identify the critical indicators distinguishing the different phases of germination pea seeds. Therefore, the presented OCT approach offers a fast and nondestructive way to precisely measure the structural indicators in different germination phases

Changes of SOC content in China's Shendong coal mining area during 1990–2020 investigated using remote sensing techniques

Coal mining, an important human activity, disturbs soil organic carbon (SOC) accumulation and decomposition, eventually affecting terrestrial carbon cycling and the sustainability of human society. However, changes of SOC content and their relation with influential factors in coal mining areas remained unclear. In the study, predictive models of SOC content were developed based on field sampling and Landsat images for different land-use types (grassland, forest, farmland, and bare land) of the largest coal mining area in China (i.e., Shendong). The established models were employed to estimate SOC content across the Shendong mining area during 1990–2020, followed by an investigation into the impacts of climate change and human disturbance on SOC content by a Geo-detector. Results showed that the models produced satisfactory results (R$^2$ > 0.69, p < 0.05), demonstrating that SOC content over a large coal mining area can be effectively assessed using remote sensing techniques. Results revealed that average SOC content in the study area rose from 5.67 gC·kg$^{−1}$ in 1990 to 9.23 gC·kg$^{−1}$ in 2010 and then declined to 5.31 gC·Kg$^{−1}$ in 2020. This could be attributed to the interaction between the disturbance of soil caused by coal mining and the improvement of eco-environment by land reclamation. Spatially, the SOC content of farmland was the highest, followed by grassland, and that of bare land was the lowest. SOC accumulation was inhibited by coal mining activities, with the effect of high-intensity mining being lower than that of moderate- and low-intensity mining activities. Land use was found to be the strongest individual influencing factor for SOC content changes, while the interaction between vegetation coverage and precipitation exerted the most significant influence on the variability of SOC content. Furthermore, the influence of mining intensity combined with precipitation was 10 times higher than that of mining intensity alone

Development of a pressure coring system for the investigation of deep underground exploration

To provide a more accurate evaluation of the scale of deep underground resources, a new pressure coring system was carefully developed and its strength and safety of the engineering were verified by theoretical analyses and numerical simulation. The designed pressure coring system can obtain cores with length of 3 m and diameter of 50 mm at 70 MPa. The results of the ball-drop operation experiment demonstrate that differential motion assembly can effectively cut a safety pin by applying a tensile force of 4852 N, and it can lift the core tube through the center pole to complete a series of mechanical actions to seal the pressure. Additionally, by maintaining pressures at 70 MPa for 30 min, the pressure sealing capacity of the system was proven. Furthermore, a core sample with a diameter of 50 mm was obtained through a core drilling experiment and the coring performance of the pressure coring system was verified. This study can not only enrich the existing onshore coring technology but also provide a theoretical guide and design criteria for the development of similar pressure coring systems to meet the demand for deeper underground exploration