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In order to effectively prevent the spontaneous combustion of residual coal in goaf, taking the 10,101 fully mechanized top coal caving face of Baozigou coal mine as research object, the multi-field coupling numerical model of nitrogen injection in goaf is established. The FLUENT software is used to study the variation law of spontaneous combustion zone in goaf under dynamic mining of working face with different nitrogen injection parameters, determining the range of spontaneous combustion zone in stable stage. The fitting curve between nitrogen injection parameters and width of spontaneous combustion zone in goaf is obtained. Results show that with the increase of nitrogen injection depth from 10 to 60 m, the width of spontaneous combustion zone in goaf begins to decrease gradually, yet the width of spontaneous combustion zone tends to expand after more than 40 m. When the nitrogen injection location is 40 m, the spontaneous combustion zone width decreases from 49 to 22 m as the nitrogen injection volume increases from 500 to 1000 m3/h. Nitrogen injection continuously reduces the area of high temperature zone and temperature extreme value. When the nitrogen injection parameter is set to (40 m–1000 m3/h), temperature extreme value decreases by 308.85 K compared with that without nitrogen injection. When the nitrogen injection parameter is (40 m–690 m3/h), it can meet the inert cooling requirements of goaf. The width of spontaneous combustion zone is 31 m and the temperature extreme value is 309.95 K at the moment. Finally, engineering application of the fire prevention technology combining shot-off loss wind and nitrogen injection is used to test effect of spontaneous combustion prevention and verify accuracy of nitrogen injection simulation. CO concentration at the measuring point 1, 3 and 5 are reduced to 0 × 10−3‰, 2 × 10−3‰ and 1.2 × 10−3‰, and temperature are reduced to 295.15 K, 296.15 K and 295.65 K respectively. It shows that the spontaneous combustion of residual coal in goaf has been successfully controlled. [ABSTRACT FROM AUTHOR]

In order to effectively prevent the spontaneous combustion of residual coal in goaf, taking the 10,101 fully mechanized top coal caving face of Baozigou coal mine as research object, the multi-field coupling numerical model of nitrogen injection in goaf is established. The FLUENT software is used to study the variation law of spontaneous combustion zone in goaf under dynamic mining of working face with different nitrogen injection parameters, determining the range of spontaneous combustion zone in stable stage. The fitting curve between nitrogen injection parameters and width of spontaneous combustion zone in goaf is obtained. Results show that with the increase of nitrogen injection depth from 10 to 60 m, the width of spontaneous combustion zone in goaf begins to decrease gradually, yet the width of spontaneous combustion zone tends to expand after more than 40 m. When the nitrogen injection location is 40 m, the spontaneous combustion zone width decreases from 49 to 22 m as the nitrogen injection volume increases from 500 to 1000 m3/h. Nitrogen injection continuously reduces the area of high temperature zone and temperature extreme value. When the nitrogen injection parameter is set to (40 m–1000 m3/h), temperature extreme value decreases by 308.85 K compared with that without nitrogen injection. When the nitrogen injection parameter is (40 m–690 m3/h), it can meet the inert cooling requirements of goaf. The width of spontaneous combustion zone is 31 m and the temperature extreme value is 309.95 K at the moment. Finally, engineering application of the fire prevention technology combining shot-off loss wind and nitrogen injection is used to test effect of spontaneous combustion prevention and verify accuracy of nitrogen injection simulation. CO concentration at the measuring point 1, 3 and 5 are reduced to 0 × 10−3‰, 2 × 10−3‰ and 1.2 × 10−3‰, and temperature are reduced to 295.15 K, 296.15 K and 295.65 K respectively. It shows that the spontaneous combustion of residual coal in goaf has been successfully controlled. [ABSTRACT FROM AUTHOR]

Ferroptosis is a form of regulated cell death characterized by oxidative injury-induced lipid peroxidation. However, the detailed protein post-translational modification regulatory mechanism of ferroptosis remains largely unknown. Here, we report that E1A binding protein P300 (EP300) acetyltransferase promotes ferroptosis in human pancreatic ductal adenocarcinoma (PDAC) cells via the acetylation of heat shock protein family A (Hsp70) member 5 (HSPA5), also known as GRP78 or BIP) on the site of K353. Acetylated HSPA5 loses its ability to inhibit lipid peroxidation and subsequent ferroptotic cell death. Genetic or pharmacological inhibition of EP300-mediated HSPA5 acetylation on K353 increases PDAC cell resistance to ferroptosis. Moreover, histone deacetylase 6 (HDAC6) limits HSPA5 acetylation and subsequent ferroptosis. Collectively, these findings not only identify regulatory pathways for HSPA5 acetylation during ferroptosis, but also highlight promising strategies to increase ferroptosis sensitivity in PDAC cells. [ABSTRACT FROM AUTHOR]

Alkaliptosis is a recently discovered type of pH-dependent cell death used for tumor therapy. However, its underlying molecular mechanisms and regulatory networks are largely unknown. Here, we report that the acetate-activating enzyme acetyl-CoA short-chain synthase family member 2 (ACSS2) is a positive regulator of alkaliptosis in human pancreatic ductal adenocarcinoma (PDAC) cells. Using qPCR and western blot analysis, we found that the mRNA and protein expression of ACSS2 was upregulated in human PDAC cell lines (PANC1 and MiaPaCa2) in response to the classic alkaliptosis activator JTC801. Consequently, the knockdown of ACSS2 by shRNAs inhibited JTC801-induced cell death in PDAC cells, and was accompanied by an increase in cell clone formation and a decrease in intracellular pH. Mechanically, ACSS2-mediated acetyl-coenzyme A production and subsequent histone acetylation contributed to NF-κB–dependent CA9 downregulation, and this effect was enhanced by the histone deacetylase inhibitor trichostatin A. These findings may provide new insights for understanding the metabolic basis of alkaliptosis and establish a potential strategy for PDAC treatment. [ABSTRACT FROM AUTHOR]

Cognitive impairment is one of the most common problem saffecting older adults. In this study, we investigated whether Tai Chi Chuan and Baduanjin practice can modulate mental control functionand the resting state functional connectivity (rsFC) of the cognitive control network in older adults. Participants in the two exercise groups practiced either Tai Chi Chuan or Baduanjin for 12 weeks, and those in the control group received basic health education. Memory tests and fMRI scans were conducted at baseline and at the end of the study. Seed-based (bilateral dorsolateral prefrontal cortex, DLPFC) rsFC analysis was performed. We found that compared to the controls, 1) both Tai Chi Chuan and Baduanjin groups demonstrated significant improvements in mental control function; 2) the Tai Chi Chuan group showed a significant decrease in rsFC between the DLPFC and the left superior frontal gyrus (SFG) and anterior cingulate cortex; and 3) the Baduanjin group showed a significant decrease in rsFC between the DLPFC and the left putamen and insula. Mental control improvement was negatively associated with rsFC DLPFC-putamen changes across all subjects. These findings demonstrate the potential of Tai Chi Chuan and Baduanjin exercises in preventing cognitive decline. [ABSTRACT FROM AUTHOR]

Gastric carcinoma (GC) is the second leading cause of cancer-related mortality worldwide. The efficacy of standard chemotherapy for GC, such as cisplatin (CDDP), is dissatisfactory partly due to the toxic/side-effects. Sulforaphane (SFN), which exhibits effective anti-cancer functions, is a phytochemical converted from cruciferous plants. Our present study aimed to identify whether SFN could enhance the anti-cancer effects of low-dose CDDP and to determine the underlying mechanisms. Herein, co-exposure of SFN and CDDP significantly inhibited the viabilities of gastric cancer cells. For the molecular mechanisms, CDDP alone increased the cancer stem cell (CSC)-like properties in gastric cancer cells via activating the interleukin-6 (IL-6)/IL-6 receptor (IL-6R)/signal transducer and activator of transcription 3 (STAT3) signaling. However, SFN could activate the microRNA-124 (miR-124), which directly targets the 3′-untranslated regions (UTR) of the IL-6R and STAT3. Moreover, knockdown of miR-124 eliminated the effects of SFN on CSC-like properties in GC cells, and in turn enhanced the anti-cancer effects of low-dose CDDP. These findings not only suggested a mechanism whereby SFN enhanced the anti-cancer functions of CDDP, but also helped to regard SFN as a potential chemotherapeutic factor in gastric cancer. [ABSTRACT FROM AUTHOR]