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While many studies have examined the role of biochar in carbon (C) accrual in short-term scale, few have explored the decadal scale influences of biochar on non-biochar C, e.g., native soil organic C (SOC) and added substrate. To address this knowledge gap, soils were collected from decade-old biochar field trials located in the United Kingdom (Cambisol) and China (Fluvisol), with each site having had three application rates (25–30, 50–60 and 75–100 Mg ha−1) of biochar plus an unamended Control, applied once in 2009. We assessed physicochemical and microbial properties associated with sucrose (representing the rhizodeposits) mineralization and the priming effect (PE) on native SOC. Here, we showed both soils amended with biochar at the middle application rate (50 Mg ha−1 biochar in Cambisol and 60 Mg ha−1 biochar in Fluvisol) resulted in greater substrate mineralization. The enhanced accessibility and availability of sucrose to microorganisms, particularly fast-growing bacterial genera like Arenimonas, Spingomonas, and Paenibacillus (r-strategists belonging to the Proteobacteria and Firmicutes phyla, respectively), can be attributed to the improved physicochemical properties of the soil, including pH, porosity, and pore connectivity, as revealed by synchrotron-based micro-CT. Random forest analysis also confirmed the contribution of the microbial diversity and physical properties such as porosity on sucrose mineralization. Biochar at the middle application rate, however, resulted in the lowest PE (0.3 and 0.4 mg of CO2-C g soil−1 in Cambisol and Fluvisol, respectively) after 53 days of incubation. This result might be associated with the fact that the biochar promoted large aggregates formation, which enclosed native SOC in soil macro-aggregates (2–0.25 mm). Our study revealed a diverging pattern between substrate mineralization and SOC priming linked to the biochar application rate. This suggests distinct mechanisms, biophysical and physicochemical, driving the mineralization of non-biochar carbon in a field where biochar was applied a decade before. Highlights: The application of biochar at a moderate rate (50–60 Mg ha−1) resulted in increased labile C mineralization and decreased priming of native SOC. Biochar amendments led to the reconfiguration of physicochemical properties, including pH, porosity, and the formation of aggregates. Modified microbial community structure towards more r-strategists caused greater sucrose mineralization. Biochar incorporation rate governed the C dynamics via (biophysical vs physicochemical mechanisms) in long-term biochar amended fields. [ABSTRACT FROM AUTHOR]

Background/Aims: Alcohol consumption has been shown to cause neuroinflammation and increase a variety of immune-related signaling processes. Microglia are a crucial part of alcohol-induced neuroinflammation and undergo apoptosis. Even though the importance of these inflammatory processes in the effects of alcohol-related neurodegeneration have been established, the mechanism of alcohol-induced microglia apoptosis is unknown. In prior research, we discovered that alcohol increases expression of salt-inducible kinase 1 (SIK1) in rodent brain tissue. In this study, we sought to determine what role SIK1 expression plays in alcohol-induced neuroinflammation as well as whether and by what mechanism it regulates microglia apoptosis. Methods: Adult C57BL/6 mice were divided into four groups and for 3 weeks treated with either 0%, 5%, 10%, or 15% alcohol during 3 hour periods. The mice were sacrificed and their brains excised for analysis. Additionally, primary microglia were isolated from neonatal mice. SIK1 expression in alcohol-treated brain tissue and microglia was analyzed via RT-PCR and western blotting. TUNEL staining, caspase-3, and caspase-9 activity assays were performed to evaluate microglial apoptosis. Cell fluorescence staining and NF-κB luciferase activity assays were used to evaluate the effects of SIK1 expression on the NF-κB signaling pathway. Results:SIK1 expression was increased in the brains of mice that consumed alcohol, and this effect was seen in mouse primary microglia. SIK1 knockdown in microglia increased alcohol-induced apoptosis in these cells. Furthermore, SIK1 reduced NF-κB signaling pathway factors, and SIK1 knockdown in microglia promoted alcohol-induced NF-κB activity. TUNEL staining, caspase-3, and caspase-9 activity assays consistently revealed that alcohol-induced microglial apoptosis was inhibited by depletion of p65. Finally, we determined that NF-κB signaling is required for alcohol-induced, SIK1-mediated apoptosis in microglia. Conclusion: This study establishes for the first time not only that SIK1 is crucial to regulating alcohol-induced microglial apoptosis, but also that the NF-κB signaling pathway is required for its activity. Overall, our results help elucidate mechanisms of alcohol-induced neuroinflammation. [ABSTRACT FROM AUTHOR]

It was reported that γ-irradiation had a controversial therapeutic effect on glioma cells. We aimed to investigate the cytotoxic effect on the glioma cells induced by γ-irradiation and explore the treatment to rescue the phenotype alteration of remaining cells. We used transwell assay to detect the glioma cell invasion and migration capacity. Cell proliferation and apoptosis were tested by the CCK-8 assay and flow cytometry respectively. Western Blot was used to detect the activity of Hedgehog signaling pathway and Epithelial-to-Mesenchymal Transition (EMT) status. γ-irradiation showed cytotoxic effect on LN229 cellsin vitro, whereas this contribution was limited in U251 cells. However, it could significantly stimulated EMT process in both LN229 and U251. Curcumin (CCM) could rescue EMT process induced by γ-irradiation via the suppression of Gli1 and the upregulation of Sufu. The location and expression of EMT markers were also verified by Immunofluorescence. Immunohistochemistry assay was used on intracranial glioma tissues of nude mice. The capacities of cell migration and invasion were suppressed with combined therapy. This research showed Curcumin could rescue the EMT process induced by γ-irradiation via inhibiting the Hedgehog signaling pathway and potentiate the cell cytotoxic effectin vivoandin vitro. [ABSTRACT FROM PUBLISHER]

Background: In recent years, miRNAs have been suggested to play key roles in the formation and development of human glioma. The aim of this study is to investigate the effect and mechanism of miR-184 expression on the malignant behavior of human glioma cells. Methods: The relative quantity of miR-184 was determined in human glioma cell lines, and the expression of hypoxia-inducible factor-1 alpha (HIF-1α) was explored using western blotting. The effects of miR-184 inhibition on cell viability and apoptosis were explored, and the miR-184 target gene was determined using a luciferase assay and western blotting. Flow cytometry and Hoechst staining were used to evaluate cell growth and apoptosis. Matrigel invasion and scratch assays were performed to measure the ability of cell invasion and migration. Results: miR-184 and HIF-1α protein levels were significantly upregulated in human glioma cells. Downregulation of miR-184 inhibited cell viability and increased the HEB cell apoptotic rate. Luciferase and western blot assays verified that FIH-1 was the target gene of miR-184 and negatively controlled the protein level of HIF-1α. Inhibition of HIF-1α by siRNA facilitated the apoptosis of HEB cells and suppressed A172 cell invasion and migration. Conclusion: miR-184 upregulation enhanced the malignant phenotype of human glioma cancer cells by reducing FIH-1 protein expression. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Soil compaction has become a global concern that reduces soil quality and may jeopardize agricultural sustainability. The objective of this study is to evaluate if the freezing–thawing process can alleviate the negative effects of soil compaction during overwinter time in Northeast China. The field experiment was a split plot design including two surface treatments (bare and mulch) and three compaction levels (low, moderate, and high compactions with initial bulk densities of 1.2, 1.4 and 1.6 g cm−3). Results showed that compared with initial values in the fall, freezing–thawing events increased soil porosity (by 4.28% to 25.68%) and the ratio of large-size pores (by 44.5% to 387.6%) after thawing in the spring. The greatest changes were observed in the high compaction treatment, and mulch-enhanced soil structural transformation. Additionally, the ratio of large-size aggregates (>1 mm) was increased and the fraction of small-size aggregates (<1 mm) was decreased. These changes in soil structural characteristics were attributed mainly to the modification of ice-filled pores space during the overwinter period. We concluded that the freezing–thawing process was an effective natural force for ameliorating soil compaction in Northeast China. [ABSTRACT FROM AUTHOR]

Maize eyespot, caused by Kabatiella zeae , has become a major yield-limiting factor in maize planting areas in northeast China. Limited information is available on pathotypes, virulence, and the genetic diversity of the K. zeae population. We analyzed virulence and genetic diversity of 103 K. zeae isolates collected from six provinces in China with differential hosts and the amplified fragment length polymorphism (AFLP) technique, respectively. To evaluate the virulence, 103 isolates were inoculated on nine differential hosts (maize inbred lines)-E28, Shen137, Qi319, B73, Danhuang34, Zi330, Mo17, Huangzaosi, and CN165-and grouped into 23 pathotypes and three virulence groups according to the coded triplet nomenclature system on differential hosts. AFLP analysis resolved the set of isolates into four genetic diversity clusters (DICE similarity values of 76%). Genetic variation of K. zeae among and between pathotypes revealed that the pathogen population had a high genotypic diversity. The correlation between pathotypes, virulence, and genetic diversity grouping was low. A correlation between AFLP groups and geographic locations was detected.

The role of NADPH oxidases (NOXs) in pathogenesis and development in the Curvularia leaf spot agent Curvularia lunata remains poorly understood. In this study, we identified C . lunata ClNOX2, which localized to the plasma membrane and was responsible for reactive oxygen species (ROS) generation. Scavenging the ROS production inhibited the conidial germination and appressorial formation. The ClNOX2 and ClBRN1 deletion mutants were defective in 1,8-dihydroxynaphthalene (DHN) melanin accumulation, appressorial formation, and cellulase synthesis and exhibited lower virulence. However, disruption of the ClNOX2 and ClBRN1 genes facilitated hyphal growth, enhanced stress adaptation to cell-wall-disrupting agents, and promoted developmental processes such as conidiation, conidial germination, and pseudothecium and ascus formation. Interestingly, loss of ClM1 , the cell wall integrity (CWI) mitogen-activated protein kinase gene in C . lunata , led to morphology and pathogenicity phenotypes similar to ClNOX2 and ClBRN1 deletion mutants such as abnormal conidia, fewer appressoria, less melanin, increased hyphal growth, and enhanced tolerance to Congo red (CR). These results indicated that the ClNOX2 gene plays an important role in C. lunata development and virulence via regulating intracellular DHN melanin biosynthesis. Quantitative reverse-transcription PCR revealed that the ClNOX2 -related ROS signaling pathway and ClM1 -mediated CWI signaling pathway are cross-linked in regulating DHN melanin biosynthesis. Our findings provide new insights into how ClNOX2 participates in pathogenesis and development in hemibiotrophic plant fungal pathogens.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.