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Abstract To solve the problem of severe rock pressure near coal mining face tunnels, a high‐pressure abrasive water jet slotting and roof breaking pressure relief technology is proposed. First, the laneway deformation mechanism and the process of hard rock slotting using high‐pressure abrasive water jets under long‐distance cantilever conditions are analyzed, and the crack initiation conditions of roof strata are obtained. Second, slotting tests under different slotting pressures, nozzle diameters, abrasive particle sizes and slotting times were carried out, and the slotting parameters of a high‐pressure abrasive water jet on a typical roof rock were obtained. Finally, industrial application was carried out in the 81,403 working face of Huayang No.1 Mine. After the hydraulic roof slotting measures were implemented in the test area, the maximum axial force of the anchor cable was reduced to 67 kN, which was 35.5% lower than that of the comparison. The average stress of the coal seam was 15 MPa, which was approximately 25% lower than that of the comparison. The deformation of the tunnel in the experimental area was significantly controlled, with an average movement of 30.0% toward the roof and floor of the tunnel and an average movement of 23.2% toward the two sides of the tunnel. Compared with the movement in the comparison section, the movement toward the roof and floor of the laneway was 42.3% lower, and the movement toward the two sides was 38.2% lower. The industrial application results show that high‐pressure abrasive water jet roof slotting and pressure relief technology can cut off the stress transmission path between the roof rock on both sides, effectively improve the stress state of the surrounding rock of the laneway, reduce the deformation of the roof, floor and two sides of the working face in the later stage of the mining laneway.

This study aims to investigate the effectiveness of combining serum lectin galactoside-binding soluble 3 binding protein (LGALS3BP) with growth differentiation factor 15 (GDF-15) for predicting outcomes in sepsis patients in an intensive care unit (ICU) setting. Methods: The study involved 208 sepsis patients from the ICU of our hospital. These patients were categorized based on their 28-day survival outcomes into two groups: 166 in the survival group and 42 in the mortality group. The serum levels of LGALS3BP and GDF-15 were measured using the ELISA technique. Pearson and Spearman methods were utilized for correlation analysis. Factors affecting mortality in ICU sepsis patients were evaluated through multivariate logistic regression analysis. The efficacy of these biomarkers in prognosis prediction was assessed using receiver operating characteristic (ROC) curve analysis. Results: The proportion of septic shock, APACHE II score, SOFA score, and serum LGALS3BP and GDF-15 levels in ICU sepsis patients in the death group were obviously higher than those in the survival group (P< 0.05). The severity of ICU sepsis patients, APACHE II score, and SOFA score were obviously positively correlated with serum LGALS3BP and GDF-15 levels (P< 0.05). LGALS3BP (OR: 95% CI=2.745:1.583~4.761) and GDF-15 (OR: 95% CI=2.639:1.423~4.893) were independent risk factors for death in ICU sepsis patients (P< 0.05). The AUC of serum LGALS3BP and GDF-15 levels alone in predicting death in ICU sepsis patients was 0.859 and 0.854, obviously lower than the AUC of the combination, 0.943 (Z=2.704, 2.287, P< 0.05). The AUC for predicting mortality in ICU sepsis patients using the APACHE II and SOFA scores were 0.832 and 0.842, respectively. The differences in comparison to the AUCs of LGALS3BP and GDF-15 were not statistically significant (P > 0.05). Conclusion: Serum levels of LGALS3BP and GDF-15 can both be used as predictive indicators for death in ICU sepsis patients, and their combined predictive efficacy is better. [ABSTRACT FROM AUTHOR]

After spinal cord injury (SCI), phagocytes endocytose myelin debris to form foam cells, exacerbating the inflammatory response. It has been previously shown that macrophages become foam cells through the phagocytosis of myelin debris via receptor-dependent mechanisms after SCI. Blocking receptor-mediated endocytosis did not completely prevent foam cell formation, so we investigated receptor-independent endocytosis. Here, we revealed that foam cells formed after myelin debris internalization were predominantly macrophages rather than microglia. Receptor-independent macropinocytosis has an important position in foamy macrophage formation through engagement of myelin debris endocytosis after SCI. Mechanistic studies showed that cholesterol crystallization following macropinocytosis-mediated foamy macrophage formation promoted the reactive oxygen species (ROS) production and the NOD-like receptor protein 3 (NLRP3) inflammasome activation, increasing the secretion of interleukin-1β (IL-1β). Inhibition of macropinocytosis might reverse this effect, resulting in enhanced axonal regeneration and reduced neural apoptosis, thereby improving outcomes after SCI. Overall, our study revealed a previously unrecognized role for macropinocytosis in foamy macrophages formation after SCI, and confer a promising therapeutic strategy for SCI through focus on macropinocytosis., Competing Interests: Declaration of competing interest The author declares no conflicts of interest., (Copyright © 2024. Published by Elsevier B.V.)

Objective: To fabricate an injectable composite bone substitute with hyaluronic acid (HA) and calcium sulfate and to evaluate the biocompatibility and effect of the composite on cell proliferation, osteogenic differentiation in vitro and osteogenic capability in vivo ., Methods: Calcium sulfate powder was mixed with HA solution, cross-linked HA solution, and phosphate buffer solution (PBS) in a ratio of 2∶1 ( W / V ) to get composites of CA+HA, CA+HAC, and CA. The standard extracts from above 3 materials were prepared according to ISO10993-5, and were used to culture mouse MC3T3-E1 cells. The composite biocompatibility and cell proliferation in different concentrations of extract were tested with cell counting kit-8 (CCK-8). The cells were cultured with standard medium as a control. The optimal concentration was selected for osteogenic differentiation test, and ELISA Kit was used to determine the alkaline phosphatase (ALP), collagen type I (COL-I), and osteocalcin (OCN). The femoral condylar bone defect was made on New Zealand white rabbits and repaired with CA+HA, CA+HAC, and CA. Micro-CT was done to evaluate new bone formation with bone volume/tissue volume (BV/TV) ratio at 6 and 12 weeks. HE staining was used to observe bone formation., Results: CA+HA and CA+HAC were better in injectability and stability in PBS than CA. The biocompatibility test showed that absorbance ( A ) value of CA group was significantly lower than that of control group ( P <0.05) at 6, 12, and 24 hours after culture, but no significant difference was found in A values between CA+HA group or CA+HAC group and control group ( P >0.05). The proliferation test showed 25% and 50% extract of all 3 materials had significantly higher A value than control group ( P <0.05). For 75% and 100% extract, only CA+HA group had significantly higher A value than control group ( P <0.05). And 50% extract was selected for osteogenic differentiation test. At 14 and 21 days, ALP, COL-I and OCN concentrations of CA+HA group and CA+HAC group were significantly higher than those of CA group and control group ( P <0.05). Micro-CT results showed higher BV/TV in CA+HA group and CA+HAC group than CA group at 6 and 12 weeks ( P <0.05), but no significant difference was found between CA+HA group and CA+HAC group ( P >0.05). HE staining revealed that a little bone tissue was seen in CA+HA group and CA+HAC group, but there was no bone formation in CA group at 6 weeks; more streak bone tissue in CA+HA group and CA+HAC group than CA group at 12 weeks., Conclusion: Composites prepared with calcium sulfate and HA or with cross-linked HA are stable, injectable, and biocompatible. The materials have excellent effect on proliferation and differentiation of mouse MC3T3-E1 cells. They also show good osteogenic capability in vivo . So it is a potential bone substitutes for bone defective diseases.