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The slag field of the Guyang Tunnel of Zhangjiajie-Jishou-Huaihua Railway had spontaneous combustion in the early stage after accumulation. In order to study the mechanism of spontaneous combustion and thoroughly rectify the slag field, to eliminate the adverse effects of spontaneous combustion of slag field on the surrounding environment, the spontaneous combustion tendency and mineral composition of the slag samples, as well as the formation mechanism of spontaneous combustion in the slag field were analyzed by on-site investigation, experimental testing and theoretical analysis, and the final remediation plan was determined. The data showed that the spontaneous combustion grade of the slag field was Class II, the sulfur Sp. ad of iron sulfide was 1.70% to 3.88%, the air-dry base fixed carbon FCad was 5. 4% to 9.61%, and the amount of the samples lose on ignition was 10.04% - 10. 62%. The pyrite released a lot of heat through surface oxygen absorption and oxidation, and the heat accumulation led to a continuous increase in temperature, spontaneous combustion occurrred in the slag field after reaching the ignition temperature Ts. According to the research results, the general idea of the permanent treatment plan for the slag yard was to level and close, with oxygen and water isolation. After leveling, the surface of the slag yard was spread with 0.3 m thick quicklime, then covered with a layer of 1.5 m thick clay, and the uppermost layer was covered with 0.5 m planting soil. [ABSTRACT FROM AUTHOR]

Objective: To analyze the early effectiveness of unilateral biportal endoscopic discectomy (UBED) combined with annulus fibrosus suture in the treatment of lumbar disc herniation (LDH)., Methods: The clinical data of 19 patients with LDH treated with UBED and annulus fibrosus suture between October 2020 and October 2021 were retrospectively analyzed. There were 12 males and 7 females with an average age of 39.1 years (range, 26-59 years). The operative segment was L 4, 5 in 13 cases, and L 5 , S 1 in 6 cases. The mean disease duration was 6.7 months (range, 3-15 months). Preoperative neurological examination showed that muscle strength, sensation, and tendon reflex weakened or disappeared in varying degrees. Single annulus fibrosus suture (14 cases) or anchor assisted annulus fibrosus suture (5 cases) was selected according to the location of annulus fibrosus tears. Visual analogue scale (VAS) score was used to assess the low back and leg pain before operation and at 3 days, 3 months, and 6 months after operation. Oswestry disability index (ODI) was used to evaluate the function recovery of lumbar spine before operation and at 3 days, 3 months, and 6 months after operation. At 3 days and 3 months after operation, MRI was used to examine the removal of nucleus pulposus and decompression of nerve root. MacNab criteria was used to evaluate the effectiveness at 6 months after operation and the recovery of nerve root function was recorded., Results: All operations were successfully completed with a mean operation time of 52.7 minutes (range, 40-75 minutes). There was no complication such as nerve injury, spinal cord hypertension syndrome, or dural sac tear during operation, and no complication such as infection, aggravation of nerve damage, or cerebrospinal fluid leakage after operation. All the patients were followed up 6-10 months (mean, 8.2 months). Postoperative MRI showed that the herniated disc was completely removed and nerve roots were fully decompressed. During the follow-up, there was no recurrence of disc herniation. The VAS scores of low back pain and leg pain and ODI at each time point after operation significantly improved when compared with those before operation, and those at 6 months after operation further improved than those at 3 days and 3 months after operation, all showing significant differences ( P <0.05). At 6 months after operation, MacNab standard was used to evaluate the effectiveness, and the results were excellent in 14 cases, good in 4 cases, and fair in 1 case, with an excellent and good rate of 94.7%. Neurological examination showed that the sensation and muscle strength of the affected nerve root innervated area recovered significantly when compared with those before operation ( P <0.05); the recovery of tendon reflex was not obvious, showing no significant difference when compared with that before operation ( P >0.05)., Conclusion: UBED combined with annulus fibrosus suture is a safe and effective technique for LDH and early effectiveness is satisfactory.

Objective: To explore the effects of blocking two sites of TGF-β/Smads signaling on the formation of scar-related proteins in human skin fibroblasts., Methods: Two lentivirus vectors encoding soluble TGF-β receptor II (sTβRII) and mutant Smad 4-Smad 4ΔM4 were respectively transfected into human skin fibroblast cell line human foreskin fibroblast 1 (HFF-1) cells with the optimum multiplicity of infection (MOI) of 50. The protein expressions of sTβRII and Smad 4ΔM4 of the two types of transfected cells were determined by Western blotting so as to compare with those of the untransfected cells. The HFF-1 cells were divided into 6 groups as named below according to the random number table, with 6 dishes in each group, 1×10(4) cells per dish. Co-transfection group, transfected with the two previous lentivirus vectors, mixed with the ratio of 1:1 and MOI of 50, and then stimulated with 5 ng/mL TGF-β1 for 72 h; sTβRII group, transfected with lenti-sTβRII with MOI of 50, with the other treatment as above; Smad 4ΔM4 group, transfected with lenti-Smad 4ΔM4 with MOI of 50, with the other treatment as above; negative virus group, transfected with empty lentivirus vector, with the other treatment as above; positive control group, stimulated with 5 ng/mL TGF-β1 for 72 h; and blank control group, conventionally cultured without any other treatment. After stimulation, Western blotting and real-time fluorescent quantitative RT-PCR were respectively used to determine the protein and mRNA expressions of fibronectin in cells of each group. ELISA and Sircol collagen assay were respectively used to determine the protein expressions of connective tissue growth factor (CTGF) and total collagen in the cell culture supernate of each group. Data were processed with one-way analysis of variance and SNK-(q test)., Results: (1) HFF-1 cells transfected with lenti-sTβRII and HFF-1 cells transfected with lenti-Smad 4ΔM4 respectively expressed higher levels of sTβRII protein and Smad 4ΔM4 protein compared with those of untransfected cells, confirming that HFF-1 cells transfected with the two lentivirus vectors can efficiently express the target proteins. (2) There were statistically significant differences in the protein and mRNA expressions of fibronectin in cells of the 6 groups (with F values respectively 53.536 and 24.365, P values below 0.001). The protein and mRNA expressions of fibronectin in cells of positive control group (respectively 1.60 ± 0.18 and 1.99 ± 0.40) were similar with those of negative virus group (respectively 1.60 ± 0.15 and 1.94 ± 0.28, with q values respectively 0.091 and 0.419, P values above 0.05), and they were significantly higher than those of the rest 4 groups (with q values from 5.245 to 18.228, P values below 0.05). The protein and mRNA expressions of fibronectin in cells of co-transfection group (respectively 0.60 ± 0.05 and 0.70 ± 0.11) were significantly lower than those of sTβRII group (respectively 0.89 ± 0.13 and 1.24 ± 0.17) and Smad 4ΔM4 group (respectively 0.91 ± 0.14 and 1.28 ± 0.19, with q values from 3.964 to 4.294, P values below 0.05). (3) There were statistically significant differences in the protein expressions of CTGF and total collagen in the cell culture supernate of the 6 groups (with F values respectively 107.680 and 38.347, P values below 0.001). The protein expressions of CTGF and total collagen in the cell culture supernate of positive control group were similar with those of negative virus group (with q values respectively 1.106 and 0.491, P values above 0.05), and they were significantly higher than those of the rest 4 groups (with q values from 6.414 to 26.420, P values below 0.05). The protein expressions of CTGF and total collagen in the cell culture supernate of co-transfection group were significantly lower than those of sTβRII group and Smad 4ΔM4 group (with q values from 3.424 to 7.143, P values below 0.05)., Conclusions: In human skin fibroblasts, blockage of two sites of TGF-β/Smad signaling can reduce the expression of scar related proteins which are up-regulated by TGF-β1 to a greater extent than that of blocking one single site.

Objective: To investigate the effect of nuclear factor I-C (NFI-C) on platelet-derived growth factor (PDGF)-induced up-regulation of TGF-β receptor II (TβRII) in dermal fibroblasts., Methods: A lentiviral vector containing NFI-C sequence (Lenti-GFP-NFI-C) was transfected into a human foreskin fibroblast cell line (HFF-1). Cultured HFF-1 cells, cells transfected with Lenti-GFP-NFI-C, and cells transfected with a negative virus were stimulated with PDGF-BB, and Western blotting and RT-qPCR were used to detect the expression levels of TβRII in the treated cells., Results: PDGF treatment significantly increased the expression level of TβRII in HFF-1 cells (P<0.05). The cells transfected with Lenti-GFP-NFI-C expressed a significantly lower level of TβRII than non-transfected cells in response to PDGF stimulation (P<0.05), but the negative virus showed no such inhibitory effect (P>0.05). No significant difference was found in the expression level of TβRII protein between cells transfected with Lenti-GFP-NFI-C-transfection before PDGF stimulation and the blank control cells., Conclusion: NFI-C can inhibit PDGF-induced up-regulation of TβRII and thus reduce the sensitivity of the dermal fibroblasts to TGF-β.