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Objective To observe the expression changes of lymphatic vessel endothelial receptor-1（LYVE1)+ macrophages in the synovial tissues of patients with rheumatoid arthritis （RA） and their inhibitory effects on migration, invasion, and fibroblast-to-myofibroblast transformation （FMT). Methods Immunofluorescence staining was used to qualita‐ tively and quantitatively detect LYVE1 and CD68 in synovial tissues of 45 RA patients and 45 osteoarthritis （OA） pa‐ tients. Human monocytic leukemia THP-1 cells in the logarithmic growth phase were treated with LYVE1 overexpression lentivirus in the culture medium, and LYVE1-expressing THP-1 cells were obtained after 48 h of cultivation. These cells were induced with 100 ng/mL phorbol 12-myristate 13-acetate （PMA） for 48 h to obtain LYVE1+ macrophages. Another portion of THP-1 cells were induced by only 100 ng/mL PMA for 48 h to obtain LYVE1- macrophages. Human rheumatoid arthritis fibroblasts MH7A in the logarithmic growth phase were divided into theLYVE1+ macrophage group and LYVE1- macrophage group, which were added withLYVE1+ macrophages and LYVE1- macrophages, separately. In addition, the cells containing only medium were set as the blank control group. Scratch experiment was performed to observe the migration ability of cells in each group. MH7A cells were divided into groups A, B, and C, which were added withLYVE1+ macrophages, LYVE1- macrophages, and only culture medium, respectively. Transwell invasion experiment was conducted to observe the invasion ability of cells in each group. MH7A cells were divided into the group one, group two, and the blank control group, which were added withLYVE1+ macrophages, LYVE1- macrophages, and only culture medium, respectively. Real-time quantitative PCR was used to detect the mRNA expression of FMT-related genes （COL1A1, fibronectin, α-SMA） in MH7A cells after 48 h of culture. Results The expression locations of LYVE1 and CD68 in the synovial tissues of RA and OA patients overlapped. The relative expression levels of LYVE1 in the synovial tissues of RA and OA patients were 0. 319±0. 033 and 1. 000±0. 159, respectively, with statistically significant difference between these two groups （both P<0. 05). Compared with the LYVE1- macrophage group and the blank control group, theLYVE1+ macro‐ phage group had lower cell scratch healing at 24 and 48 h of cultivation （all P<0. 05). Compared with groups B and C, the number of transmembrane cells in the group A was smaller at 24 h of cultivation （P<0. 05). Compared with groups two and the blank control group, the relative expression levels of COL1A1 mRNA, fibronectin mRNA, and α-SMA mRNA in the group one were lower at 48 h of cultivation （all P<0. 05). ConclusionLYVE1+ macrophages are underexpressed in the synovial tissues of RA patients, andLYVE1+ macrophages can inhibit the migration, invasion, and FMT. [ABSTRACT FROM AUTHOR]

BACKGROUND: Studies have shown that a certain dose of interleukin-4 intervention can yield the appropriate ratio of M1/M2 macrophage profile to generate a microenvironment conducive to bone healing and promoting bone regeneration. OBJECTIVE: To investigate the effect of interleukin-4 on NLRP3 inflammasome activation and osteoclast differentiation during bone tissue regeneration guided by bone replacement materials. METHODS: Forty-eight 6-8-week-old male SD rats were selected to establish a 5-mm diameter cranial bone defect model on the left and implanted with BioOss bone replacement material at the same time, and the periosteum was sutured. Rat models were randomly divided into control and experimental groups (n=24) at postoperative 3 days. Interleukin-4 and PBS were injected locally into the cranial bone defect area for the experimental and control groups, once a day, for 5 consecutive days. SD rats were executed at 1 and 2 weeks after surgery and skull samples were taken. Immunohistochemical staining was performed to detect the expression of cleaved caspase-1 and interleukin-1β protein. Immunofluorescence staining was performed to observe the expression of inducible nitric oxide synthase (M1 surface marker) and cleaved caspase-1 (NLRP3 indicator). Real-time fluorescence quantitative PCR was performed to detect the expression of related inflammatory factors caspase-1, interleukin-1β and osteoclast factor histone K gene. The differentiation and number of osteoclasts were observed by anti-tartrate acid phosphatase staining. At 6 and 12 weeks after surgery, micro-CT and hematoxylin-eosin staining were performed to observe the osteogenesis of the skull. RESULTS AND CONCLUSION: Immunofluorescence staining showed that the number of inducible nitric oxide synthase and cleaved caspase-1 doublestained cells in the experimental group was significantly lower than that in the control group at 1 and 2 weeks (P < 0.05). Immunohistochemical staining showed that the expression of cleaved caspase-1 and interleukin-1β in the experimental group was significantly lower than that in the control group at 1 week (P < 0.05). RT-qPCR suggested that the expression of caspase-1 mRNA in the experimental group was lower than that in the control group at 1 week (P < 0.05). The expression intensity of interleukin-1β and osteoclast factor histone K mRNA was significantly lower in the experimental group than that in the control group at postoperative 1 and 2 weeks (P < 0.05). Anti-tartrate acid phosphatase staining showed that the number of osteoclasts was significantly lower in the experimental group at 1 and 2 weeks than that in the control group (P < 0.05). Micro-CT results showed that the bone volume fraction and bone mineral density in the bone defect area were significantly higher in the experimental group than those in the control group at 6 and 12 weeks after injection (P < 0.05). Hematoxylin-eosin staining showed that 12 weeks after injection, multiple ossification centers were formed in the center of the defect in the experimental group, with scattered mature bone cells and lacunae, and a large number of osteoblasts around the material arranged into a single layer to participate in the formation of bone matrix. The results suggest that interleukin-4 may be involved in downregulating NLRP3 inflammasome expression, inhibiting the activation of caspase-1 and thus reducing the secretion of interleukin-1β, reducing the inflammatory state of the local microenvironment, as well as inhibiting osteoclast differentiation and playing a role in promoting new bone production during bone tissue regeneration guided by bone replacement materials. [ABSTRACT FROM AUTHOR]

[Objective] The research aims to reveal the influence of wind action on water erosion in the wind-water composite erosion area of the Loess Plateau, provide an effective method support for the identification of erosion material sources with different sediment particle sizes, and a theoretical reference for the identification of erosion sediment sources in the wind-water composite erosion area. [Methods] The wind erosion products were simulated by sand covering. Based on the indoor simulation experiment, the development characteristics of slope erosion after sand covering were studied, and in order to effectively distinguish the sources of erosion materials at different times, the sediment particle size was used as a fingerprint factor to identify the contribution of erosion sediment sources. [Results] Three fingerprint factors of different sediment particle size groups (particle size range: 26.303～34.674 μm, 104.713～138.038 μm, 138.038～181.970 μm) were identified as the best fingerprint factors by testing. Based on the best fingerprint factors, the average sediment contribution rates of the sand-covered layer and the loess layer were 48.2% and 51.8%, 24.8% and 75.2 %, 6.8% and 93.2%, respectively, and the MAF was greater than 0. 8 in the three stages of simulated rainfall experiments in the same soil bin. The contribution rate of sediment in the sand-covered layer was in the order: the first stage test ＞ the second stage test ＞ the third stage test, and the calculation results were consistent with the DEM. [Conclusion] Different sediment particle size groups in sediment source area and erosion sediment can be used as fingerprint factors to identify sediment sources, and the composite fingerprint method has good applicability. [ABSTRACT FROM AUTHOR]

Goal-conflict analysis of divergences in requirement engineering aims to identify, assess, and resolve divergences. The divergence is caused, because the mismatch between domain attributes and objectives makes the system unable to satisfy all objectives at the same time under boundary conditions. Boundary conditions describe disagreements in the form of linear temporal logic. Due to the lack of interpretability of arbitrary boundary conditions and the extensive manual evaluation and design required to evaluate and repair divergences, the current definition of boundary conditions is not conducive to efficient and automated evaluation and repair of divergences. Therefore, in this paper, an explainable boundary condition, called lasso boundary condition, is proposed. Lasso boundary condition intuitively describes the situation where the system diverges due to some specific preconditions. Then, a lasso boundary condition identification algorithm (LBC identifier, LBCI) based on gradual weakening is designed. LBCI gradually satisfies the boundary conditions by weakening the linear temporal logic formula. The effectiveness of lasso boundary condition and LBCI are evaluated on a baseline data set. The experimental results show that the lasso boundary condition can enhance the interpretability of the divergences and the guiding role in repairing the divergences. [ABSTRACT FROM AUTHOR]

BACKGROUND: A high fracture of the mandibular condyle is often accompanied by cartilage damage. At the same time, the muscle attached to the condyle is avulsed and becomes a free bone mass. How to speed up the concurrent healing of cartilage during bone healing has always been a clinical difficulty and challenge. OBJECTIVE: To investigate the effect of parathyroid hormone on the healing of condylar cartilage in rabbits with high condylar fracture after free reduction. METHODS: An experimental model of free reduction and fixation of condylar fracture was established in 48 New Zealand big-eared rabbits, which were randomly divided into experimental group and control group (n=20 per group). The experimental group was injected with parathyroid hormone (20 μg/kg) subcutaneously every other day, and the control group was injected with 1 mL of normal saline. The animals were sacrificed at 1, 2, 3, and 4 weeks postoperatively. The mandible condyle was histologically observed. Immunohistochemistry staining and PCR were used to detect the expression of Sox9 and matrix metalloproteinase 13 in the condylar cartilage. The study protocol was approved by the Animal Experimental Ethics Committee of Guizhou Medical University (approval No. 1700456). RESULTS AND CONCLUSION: The results of safranine O-fast green staining and hematoxylin-eosin staining indicated that there were more chondrocytes and cartilage matrix deposition in the experimental group than the control group. In the immunohistochemistry, the average absorbance of Sox9 in the experimental group was significantly higher than that in the control group within 1-3 postoperative weeks (P < 0.05). The average absorbance of matrix metalloproteinase 13 in the experimental group was lower than that in the control group within 1-3 postoperative weeks (P < 0.05). The expression of Sox9 mRNA in the experimental group was significantly higher than that in the control group within 1-3 postoperative weeks, P < 0.05). The expression of matrix metalloproteinase 13 mRNA in the experimental group was significantly lower than that in the control group within 1-3 postoperative weeks (P < 0.05). These findings indicate that intermittent subcutaneous injection of parathyroid hormone can up-regulate the expression of Sox9, inhibit the expression of matrix metalloproteinase 13, promote the transformation of mesenchymal stem cells to cartilage, and accelerate the repair of cartilage damage. [ABSTRACT FROM AUTHOR]