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Objective To explore the role and molecular mechanism of Lnc-BM in the occurrence and development of gastric cancer (GC). Methods GC tissues and paired adjacent normal tissues of 36 GC patients were collected, and the expression of Lnc-BM was detected by RT-qPCR. Colony formation and CCK-8 assays were used to investigate the proliferation of GC cells. The migration and invasion properties of GC cells were investigated via Transwell assay. RNA pull-down assay was applied to confirm the interaction between FASTK and Lnc-BM. Western blot assay was used to detect FASTK protein level in Lnc-BM overexpressing or knockdown cells. Mitochondrial respiratory capacity and the related proteins expression levels were detected by Seahorse and Western blot assays, respectively. Lnc-BM stably overexpressing GC cells were constructed and then injected subcutaneously into nude mice. The tumor growth was observed. Results Lnc-BM was highly expressed in GC tissues compared with their paired adjacent normal tissues. Lnc-BM overexpression significantly promoted GC cells proliferation migration and invasion, while Lnc-BM knockdown inhibited GC cells proliferation, migration and invasion (P < 0.05). RNA pull-down experiment demonstrated that Lnc-BM can directly bind to FASTK. Western blot results indicated that overexpression of Lnc-BM increased the protein levels of FASTK, while knockdown of Lnc-BM inhibited the expression of FASTK (P < 0.05). Compared to the control group, overexpression of Lnc-BM increased the levels of mitochondria associated proteins, such as MT-ND6 and TOM20 (P < 0.05). Seahorse results indicated that overexpression of Lnc-BM enhanced mitochondrial respiratory capacity (P < 0.05). Knocking down FASTK in Lnc-BM stably overexpressing cells can reverse the increase in mitochondrial respiratory capacity caused by Lnc-BM overexpression (P < 0.05). In vivo, the results of subcutaneously implanted tumor model in nude mouse showed that Lnc-BM overexpression promoted the tumor growth (P < 0.05). Conclusion Lnc-BM promotes GC progression by regulating mitochondrial respiratory function through the FASTK/MT-ND6 axis.

Oligodendrocyte precursor cells (OPCs) undergo an extensive and coordinated migration in the developing CNS, using the pre-formed scaffold of developed blood vessels as their physical substrate for migration. While OPC association with vasculature is critical for dispersal, equally important for permitting differentiation and proper myelination of target axons is their appropriate and timely detachment, but regulation of this process remains unclear. Here we demonstrate a correlation between the developmental formation of astrocytic endfeet on vessels and the termination of OPC perivascular migration. Ex vivo and in vivo live imaging shows that astrocyte endfeet physically displace OPCs from vasculature, and genetic abrogation of endfoot formation hinders both OPC detachment from vessels and subsequent differentiation. Astrocyte-derived semaphorins 3a and 6a act to repel OPCs from blood vessels at the cessation of their perivascular migration and, in so doing, permit subsequent OPC differentiation by insulating them from a maturation inhibitory endothelial niche.

The occurrence of gastric cancer is closely related to environmental, genetic, and epigenetic factors. Currently, RNA modification is a research frontier and hotspot in the field of epigenetics. With the advancements in analytical chemistry and high-throughput sequencing technologies, new technologies and methods of exploring RNA modification are constantly being presented. Numerous studies have confirmed the involvement of RNA modifications in the occurrence and development of various diseases. Recent studies have shown that RNA modifications such as m6A, m5C, and ac4C regulate the malignant progression of various tumors, including gastric cancer, liver cancer, colorectal cancer, and leukemia. This article systematically reviews the research status and mechanism of different RNA modifications in the occurrence and development of gastric cancer, as well as discusses its potential value in the diagnosis and treatment of gastric cancer.

A large amount of NOx will be produced during the combustion process of waste energetic materials (EMs), which is extremely harmful to human health and ecological environment, and has become an urgent problem for all countries to solve. In this paper, the NOx emission characteristics of four typical types of waste EMs (double-base propellant, TNT, triple-base propellant and RDX) under different temperature and atmosphere conditions were studied by tube furnace experiment. The results showed that under the condition of nitrogen environment, with the increase of temperature, the combustion reaction of waste EMs was accelerated, NOx emission and nitrogen conversion rate decreased. Under the same experimental conditions, the nitrogen content of waste EMs was not proportional to nitrogen conversion. With the increase of oxygen content, NOx emissions and nitrogen conversion rate increased, which was not conducive to the control of NOx emissions. Therefore, the waste EMs burned in 1000 ℃ and nitrogen environment, the emission of NOx was the lowest. The results of this study provide reliable data support for the realization of green and clean burning of waste EMs.

M2‐polarized tumor‐associated macrophages (M2 TAMs) promote cancer progression. Exosomes mediate cellular communication in the tumor microenvironment (TME). However, the roles of exosomes from M2 TAMs in gastric cancer progression are unclear. Herein, it is reported that M2 TAMs‐derived exosomes induced aerobic glycolysis in gastric cancer cells and enhanced their proliferation, metastasis, and chemoresistance in a glycolysis‐dependent manner. It is identified that MALAT1 (metastasis‐associated lung adenocarcinoma transcript 1) is enriched in M2 TAM exosomes and confirmed that MALAT1 transfer from M2 TAMs to gastric cancer cells via exosomes mediates this effect. Mechanistically, MALAT1 interacted with the δ‐catenin protein and suppressed its ubiquitination and degradation by β‐TRCP. In addition, MALAT1 upregulated HIF‐1α expression by acting as a sponge for miR‐217‐5p. The activation of β‐catenin and HIF‐1α signaling pathways by M2 TAM exosomes collectively led to enhanced aerobic glycolysis in gastric cancer cells. Finally, a dual‐targeted inhibition of MALAT1 in both gastric cancer cells and macrophages by exosome‐mediated delivery of siRNA remarkably suppressed gastric cancer growth and improved chemosensitivity in mouse tumor models. Taken together, these results suggest that M2 TAMs‐derived exosomes promote gastric cancer progression via MALAT1‐mediated regulation of glycolysis. The findings offer a potential target for gastric cancer therapy. [ABSTRACT FROM AUTHOR]

Hirschsprung disease (HSCR) is a congenital disorder caused by the defective function of the embryonic enteric neural crest. The impaired migration of embryonic enteric neural crest plays an important role in the pathogenesis of this disease. Recent studies showed that the ARP2/3 complex and RAC isoforms had effects on actin cytoskeleton remodelling, which contributes to migration. Moreover, some regulatory relationships were identified between ARP2/3 complex and RAC isoforms. Although microRNAs (miRNAs) have been known to modulate target gene expression on the post-transcriptional level, little is known about the regulation among miRNAs, ARP2/3 complex and RAC isoforms. Here, we report that down-regulation of ARP2 and ARP3, two main subunits of ARP2/3 complex, suppressed migration and proliferation in 293T and SH-SY5Y cell lines via the inhibition of RAC1 and RAC2. Meanwhile, as the target genes, ARP2 and ARP3 are reduced by increased miR-24-1* and let-7a*, respectively, in 70 HSCR samples as compared with 74 normal controls. Co-immunoprecipitation showed that aberrant reduction in ARP2 and ARP3 could weaken the function of ARP2/3 complex. Our study demonstrates that the miR-24-1*/let-7a*-ARP2/3 complex-RAC isoforms pathway may represent a novel pathogenic mechanism for HSCR.

The quasi‐two‐dimensional Ruddlesden–Popper material, Sr3Sn2O7 with hybrid improper ferroelectricity, has gained significant scientific interest owing to its unique ferroelectric phase transition mechanism. However, its electrical behaviors near the phase transition temperature necessitate further investigation. In this study, high‐quality Sr3Sn2O7 ceramic was successfully prepared, and its temperature‐dependent electrical properties were systematically studied. The phase transition from ferroelectric to paraelectric of Sr3Sn2O7 ceramic near 160°C was evidenced by the varying electrical properties dependence of temperature. It is found that the space‐charge‐limited bulk conduction with deep traps is identified as dominant conduction mechanism for Sr3Sn2O7 ceramic that has high resistivity. An abnormal increasing trend of coercive field with temperature was observed and is discussed with trap‐filling process and octahedral rotation distortion. Interestingly, Sr3Sn2O7 ceramic exhibits negative piezoelectric effect and negative electrostriction responded to biased electric field, which is dramatically influenced by ferroelectric polarization. Overall, this study serves as a reference for exploring the electrical properties of other hybrid improper ferroelectrics, particularly near their Curie temperature. [ABSTRACT FROM AUTHOR]

The use efficiency of fertilizer N decreased gradually during the grain production in black soil region in northeast China. Through a ten-year long experiment on wheat, corn and soybean, the evaluation on soil capacity of keeping and supplying N under three different soil management patterns using 15N have been conducted. The results showed there was no significant difference between the three management patterns in wheat removal of soil N, while the removal of fertilizer differed significantly; the residual rate of fertilizer was 12.84%,15.28% and17.51% respectively in pattern Ⅰ, pattern Ⅱ and pattern Ⅲ, and the loss rates of fertilizer in the three patterns were 57.93%, 49.49% and 42.07% respectively. Under the patternⅠmanagement, soil N removal by corn was less. There were no significant differences on the soil N removal between pattern Ⅱand pattern Ⅲ. The loss ratios were 54.19%, 46.61% and 39.94% in patternⅠ, Ⅱ and Ⅲ respectively. The order of utilizing N efficiency of soybean was pattern Ⅲ>pattern Ⅱ>pattern Ⅰ. The use efficiency of fertilizer N of wheat, corn and soybean were 29.93%, 32.01 and 26.85% respectively under the fertilization and rotation conditions (patternⅠ), 35.23%, 37.22% and 31.25% respectively under the management of fertilizer plus organic manure (Pattern Ⅱ) and 40.42%, 41.98% and 39.55% respectively under the management of intercrop of corn and sweet clover in which the sweet clover were returned to the field (Pattern Ⅲ).