[Spatial and temporal distribution characteristics of extreme wind and its effect on wind erosion in Northeast China]. / ä¸œåŒ—åœ°åŒºæžç«¯å¤§é£Žæ—¶ç©ºåˆ†å¸ƒç‰¹å¾åŠå ¶å¯¹é£Žèš€é‡çš„å½±å“.

Under the background of climate change, extreme wind events occur frequently in Northeast China, and the soil erosion caused by these extreme wind events has attracted progressively more attention from scholars. We used the methods of linear analysis, Sen+Mann-Kendal trend analysis, and Kriging interpolation to analyze the spatial and temporal characteristics of extreme wind in Northeast China from 2005 to 2020, and used the RWEQ wind erosion estimation model to calculate the annual soil wind erosion of typical wind erosion sites and wind erosion under extreme wind conditions. The results showed that the extreme wind frequency in Northeast China presented a significant upward trend from 2005 to 2020, with an increase of 2.9 times·a-1. The annual average extreme wind frequency in Northeast China ranged from 1 to 49 times·a-1, and the high frequency areas were distributed in the northwest of Xilin Gol, the west of the Hulunbuir Plateau, and the northeast of Changbai Mountain. The average contribution rate of extreme wind to soil wind erosion in four typical sites (Xilinhot, New Barhu Right Banner, Nenjiang, and Tongyu) was 31%.

In situ formation of 2-thiobarbituric acid incorporated g-C3N4 for enhanced visible-light-driven photocatalytic performance.

Embedding heterocycles into the skeleton of g-C3N4 has been proved to be a simple and efficient strategy for improving light response and the separation of photo-excited charges. Herein, 2-thiobarbituric acid incorporated g-C3N4 (TBA/CN) with good photocatalytic efficiency for Rh B degradation and H2 production was successfully achieved via a facile thermal copolymerization approach. The incorporation of aromatics and S atoms into the skeleton of g-C3N4 was identified via systematic characterizations. This unique structure contributed to the narrowed band-gap, extended delocalization of lone pair electrons and changed electron transition pathway, which led to the enhanced visible light utilization, accelerated charge migration and prolonged electron lifetime, subsequently resulting in the significant boost of photocatalytic activity. The optimal TBA/CN-3 sample yielded the largest Rh B degradation rate constant k value of 0.0273 min-1 and simultaneously highest rate of H2 evolution of 0.438 mmol g-1 h-1, which were almost 3.5 and 3.8 folds as fast as that of the pristine CN, respectively. Finally, the photocatalytic mechanism was proposed for the detailed elucidation of the process of Rh B degradation coupled with H2 production.

Proanthocyanidin promotes functional recovery of spinal cord injury via inhibiting ferroptosis.

Improving the microenvironment of lesioned spinal cord to minimize the secondary injury is one important strategy to treat spinal cord injury (SCI). The ensuing hemorrhage after SCI has tight connection with ferroptosis. This study investigated the effects of proanthocyanidins (PACs) on SCI repair and the underlying mechanisms. Adult female mice were divided into four groups, including sham, SCI, PACs5 and PACs10 (i.p. 5 and 10 mg/kg PACs after SCI respectively). The impacts of SCI and PACs treatment on redox parameters (iron contents, TBARS, GSH, and GPX activities) and ferroptosis essential factors such as ACSL4, LPCAT3, Alox15B, Nrf2, HO-1, GPX4 were investigated. The results demonstrated that PACs treatment significantly decreased the levels of iron, TBARS, ACSL4, and Alox15B, while increased the levels of GSH, GPX4, Nrf2, and HO-1 in traumatic spinal cords. Above all, PACs improved the locomotive function of SCI mice. These results suggest that PACs might be potential therapeutics for SCI repair by inhibiting ferroptosis in SCI.

Estimating low eroded sediment concentrations by turbidity and spectral characteristics based on a laboratory experiment.

Automatic and real-time monitoring of sediment concentrations in eroded runoff is an effective way to accurately assess soil erosion process on slopes. It is assumed that low sediment concentrations could be inferred from turbidity and spectral characteristics, which are two simple and economical observation methods, and the soil properties would affect this kind of measurements. Four kinds of soil are used to obtain water samples with low sediment concentrations (0.1-10 mg/L), namely, black soil (BS), albic soil (AS), cinnamon soil (CS), and brown soil (BRS). The turbidity and spectral characteristics of the samples are measured to evaluate the relationships by calibration and validation between sediment concentrations and turbidity (method 1), sediment concentrations and reflectance with several transformations (method 2), and sediment concentrations and both indicators (method 3). The influences of soil properties on these relationships are also discussed. The linear relationship between sediment concentrations and turbidity is significant in each sample (method 1). Method 2 has a lower accuracy than method 1, in which the obtained characteristic bands and fitting models are different among samples, with a poor result for BS samples and acceptable results for the other samples. Overall, method 3 has the highest accuracy. The order of simulation accuracy from high to low is generally BS > AS > BRS > CS. The influences of soil properties are obvious and various. The effects of soil median diameter (d50) and specific surface area (SSA) on turbidity coefficients and characteristic spectral bands are not significant, but the soil organic matter (SOC) contents are. The results indicate that measurement of sediment concentration within low ranges by both turbidity and spectroscopic techniques has good accuracy in method 3, and different samples should be calibrated in application due to the effects of various soil properties.

LncRNA MAGI2-AS3 Upregulates Cytokine Signaling 1 by Sponging miR-155 in Non-Small Cell Lung Cancer.

Background: MAGI2-AS3 has been reported to be a tumor suppressor in breast cancer and bladder cancer. This study analyzed the role of MAGI2-AS3 in non-small cell lung cancer (NSCLC). Results: The authors found that MAGI2-AS3 and suppressor of cytokine signaling 1 (SOCS-1) were both downregulated in NSCLC. MAGI2-AS3 and SOCS-1 were significantly and positively correlated in NSCLC tumor tissues. During follow-up, low levels of MAGI2-AS3 and SOCS-1 were found to be significantly correlated with patients' poor survival. In NSCLC cells, MAGI2-AS3 overexpression mediated the upregulated, while miR-155 expression mediated the downregulated SOCS-1 overexpression. RNA binding analysis showed that MAGI2-AS3 may be a sponge of miR-155. Cell proliferation revealed decreased cell proliferation rate of NSCLC cells after MAGI2-AS3 and SOCS-1 overexpression. MiR-155 played an opposite role and reduced the effects of MAGI2-AS3 overexpression. Conclusion: Therefore, MAGI2-AS3 upregulates cytokine signaling 1 by sponging miR-155 to inhibit NSCLC cell proliferation.

Baicalein, as a Prooxidant, Triggers Mitochondrial Apoptosis in MCF-7 Human Breast Cancer Cells Through Mobilization of Intracellular Copper and Reactive Oxygen Species Generation.

BACKGROUND: Baicalein, a natural flavonoid derived from traditional Chinese herb Scutellaria baicalensis Georg (known as Huang Qin in Chinese), has been reported to exhibit notable antitumor activity in various cancer cells, including breast cancer. However, the detailed mechanisms underlying its induced apoptosis as a prooxidant in breast cancer cells are still unknown. MATERIALS AND METHODS: In this study, we investigated the effect of endogenous copper on cytotoxic activity of baicalin against human breast cancer MCF-7 cells in vitro. RESULTS: Baicalein could remarkably reduce the cell viability in both dose- and time-dependent manners in MCF-7 cells but with lower cytotoxic effects on normal breast epithelial cells, MCF-10A. Such cell death could be prevented by pretreatment with Cu (I)-specific chelator neocuproine (Neo) and reactive oxygen species (ROS) scavengers. Meanwhile, baicalein could induce MCF-7 cell morphological changes, promote apoptotic cell death and increase the apoptotic cell number. Moreover, DCHF-DA staining, flow cytometry and Western blotting analyses proved that baicalein triggered the mitochondrial-dependent apoptotic pathway, as indicated by enhancement the level of intracellular ROS, disruption of mitochondrial membrane potential (ΔΨm), downregulation of anti-apoptotic protein Bcl-2, upregulation of pro-apoptotic protein Bax, release of cytochrome C and activation of caspase-9 and caspase-3 in MCF-7 cells. The pretreatment with Neo remarkably weakened these effects of baicalein. Furthermore, we confirmed that the prooxidant action of baicalein involved the direct production of hydroxyl radicals through redox recycling of copper ions. CONCLUSION: These findings suggested that baicalein, acting as a prooxidant, could trigger apoptosis in MCF-7 cells occurs via the ROS-mediated intrinsic mitochondria-dependent pathway.

One-pot construction of Cu and O co-doped porous g-C3N4 with enhanced photocatalytic performance towards the degradation of levofloxacin.

Low visible light response and rapid recombination of photogeneration charge carriers have always been the main factors limiting the advanced application of g-C3N4 (CN). Element doping has been confirmed to be an efficient method to improve the photocatalytic performance of CN. Here, a series of Cu and O co-doped porous g-C3N4 (Cu/O-PCN) nanomaterials were successfully fabricated by a facile one-pot thermal polymerization approach for the first time. Compared to pure CN, the resulting Cu/O-PCN exhibited remarkably enhanced visible-light-driven photocatalytic activity towards levofloxacin (LEVO) degradation. The optimized sample of 0.5% Cu doped (Cu/O-PCN-3) presented the highest degradation rate constant of 0.0676 min-1, which was about 6.2 times higher than that of CN. Furthermore, a substantial decrease in the residual toxicity against E. coli was observed after photocatalytic degradation treatment. The superior photocatalytic performance of Cu/O-PCN was mainly attributed to the synergistic advantages of stronger visible light response, larger specific surface area, and the more effective separation and transfer of photogenerated charge carriers. Moreover, according to the trapping experiments, ·O2 - and h+ were the major oxygen active species in the photocatalytic degradation process. Finally, the possible enhanced photocatalytic mechanism over Cu/O-PCN was proposed.

Optimization of the extraction, preliminary characterization, and anti-inflammatory activity of crude polysaccharides from the stems of Trapa quadrispinosa.

A novel method was developed using pressurized-assisted extraction (PAE) to efficiently extract crude Trapa quadrispinosa polysaccharides (TQCPS) from plant stems, and the extraction process was optimized using response surface methodology (RSM). At a water-to-material fixed ratio of 30 mL g-1, the highest yield of 3.72 ± 0.13% was obtained under the optimum conditions of extraction time of 32 min, extraction temperature at 47 °C, and extraction pressure at 1.87 Mpa, which were in agreement with the predicted value of 3.683%. Compared with conventional hot water extraction (HWE), the PAE method remarkably enhanced the extraction yield with the further advantages of short extraction time and low extraction temperature. The preliminary characteristics of TQCPS were analyzed through UV-vis, FT-IR, and chemical composition analysis. In subsequent anti-inflammatory studies, when RAW 264.7 mouse macrophage cells were treated with TQCPS, satisfactory anti-inflammatory activity was observed, and TQCPS significantly suppressed the release of nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) and synchronously restrained the expression levels of inducible nitric oxide synthase (iNOS), TNF-α, and IL-6 mRNA induced by lipopolysaccharide (LPS) in a dose-dependent manner. These results indicate that PAE is a technology that can be used for efficient extraction of polysaccharides from medicinal plants, and TQCPS can be explored as a potential anti-inflammatory agent in medicine.

Long Non-Coding RNAs in Hepatitis B Virus-Related Hepatocellular Carcinoma: Regulation, Functions, and Underlying Mechanisms.

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer death in the world. Hepatitis B virus (HBV) and its X gene-encoded protein (HBx) play important roles in the progression of HCC. Although long non-coding RNAs (lncRNAs) cannot encode proteins, growing evidence indicates that they play essential roles in HCC progression, and contribute to cell proliferation, invasion and metastasis, autophagy, and apoptosis by targeting a large number of pivotal protein-coding genes, miRNAs, and signaling pathways. In this review, we briefly outline recent findings of differentially expressed lncRNAs in HBV-related HCC, with particular focus on several key lncRNAs, and discuss their regulation by HBV/HBx, their functions, and their underlying molecular mechanisms in the progression of HCC.

Optimization of Surfactant-Mediated, Ultrasonic-assisted Extraction of Antioxidant Polyphenols from Rattan Tea (Ampelopsis grossedentata) Using Response Surface Methodology.

BACKGROUND: Rattan tea is a medicinal plant that has been used for many years for the treatment of inflammation, fatty liver, tumor, diabetes, and hyperlipidemia. OBJECTIVE: A green and novel approach based on surfactant-mediated, ultrasonic-assisted extraction (SM-UAE) was developed for the extraction of antioxidant polyphenols from Rattan tea. A nonionic surfactant Tween-80 was selected as extraction solvent. The antioxidant activity was measured by total phenolic content (TPC) and ferric-reducing/antioxidant capacity (FRAC) assay. MATERIALS AND METHODS: Optimization of extraction parameters including concentration of solvent, ultrasonic time, and temperature were investigated by response surface methodology. The antioxidant activity was measured by TPC and FRAC assay. RESULTS: The optimal extraction conditions were determined as 6.8% (v/v) of aqueous Tween-80, ultrasonic temperature of 54°C, and ultrasonic time of 28.8 min. Under these conditions, the highest TPC value of 360.4 mg gallic acid equivalent per gram of dry weight material (GAE/g DW) was recorded. Moreover, 6.8% (v/v) of aqueous Tween-80, ultrasonic temperature of 54.5°C, and ultrasonic time of 28.4 min were determined for the highest FRAC value of 478.2 µmol of Fe2+/g of weight material (µmol Fe2+/g DW). Compared with other methods, the TPC and FRAC values of 313.5 mg GAE/g DW and 389.6 µmol Fe2+/g DW were obtained by heat reflux extraction using ethanol as solvent, respectively, and 343.2 mg GAE/g DW and 450.1 µmol Fe2+/g DW were obtained by UAE using ethanol as solvent, respectively. CONCLUSION: The application of SM-UAE markedly decreased extraction time or extraction cost and improved the extraction efficiency, compared with the other methods. SUMMARY: Surfactant-mediated ultrasonic-assisted extraction of antioxidant polyphenols from Rattan TeaResponse surface methodology used to optimize parameters and study combined effectsOptimized surfactant-mediated ultrasonic-assisted extraction process enhances the antioxidant phenolics extraction in less time. Abbreviations used: SM-UAE: Surfactant-mediated ultrasonic-assisted extraction; TPC: total phenolic content; FRAC: Ferric reducing antioxidant capacity; RSM: Response surface methodology; BBD: Box-Behnken design.

Optimization of Ultrasonic-Assisted Enzymatic Extraction Conditions for Improving Total Phenolic Content, Antioxidant and Antitumor Activities In Vitro from Trapa quadrispinosa Roxb. Residues.

Stems are the important residues of Trapa quadrispinosa Roxb., which are abundant in phenolic compounds. Ultrasonic-assisted enzymatic extraction (UAEE) is confirmed as a novel extraction technology with main advantages of enhancing extraction yield and physiological activities of the extracts from various plants. In this study, UAEE was applied to obtain the highest yield of phenolic content, strongest antioxidant, and antitumor activities and to optimize the extraction conditions using response surface methodology (RSM). The extracts from the stems of T. quadrispinosa were characterized by determination of their antioxidant activities through 2,2-azinobis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS), 1,1-Diphenyl-2-picrylhydrazxyl (DPPH) radical scavenging, total antioxidant capacity (TAC), ferric reducing antioxidant capacity (FRAC) methods and of their antitumor activity by MTT method. The selected key independent variables were cellulase concentration (X1: 1.5%-2.5%), extraction time (X2: 20-30 min) and extraction temperature (X3: 40-60 °C). The optimal extraction conditions for total phenolic content (TPC) value of the extracts were determined as 1.74% cellulase concentration, 25.5 min ultrasonic extraction time and 49.0 °C ultrasonic temperature. Under these conditions, the highest TPC value of 53.6 ± 2.2 mg Gallic acid equivalent (GAE)/g dry weight (DW) was obtained, which agreed well with the predicted value (52.596 mg GAE/g·DW. Furthermore, the extracts obtained from UAEE presented highest antioxidant activities through ABTS, DPPH, TAC and FRAC methods were of 1.54 ± 0.09 mmol Trolox equivalent (TE)/g·DW; 1.45 ± 0.07 mmol·TE/g·DW; 45.2 ± 2.2 mg·GAE/g·DW; 50.4 ± 2.6 µmol FeSO4 equivalent/g·DW and lowest IC50 values of 160.4 ± 11.6 µg/mL, 126.1 ± 10.8 µg/mL, and 178.3 ± 13.1 µg/mL against Hela, HepG-2 and U251 tumor cells, respectively. The results indicated that the UAEE was an efficient alternative to improve extraction yield and enhance the antioxidant and antitumor activities of the extracts. The phenolic extracts from the stems of T. quadrispinosa had significant antioxidant and antitumor activities, which could be used as a source of potential antioxidant and antitumor agents.

Rutin-Nickel Complex: Synthesis, Characterization, Antioxidant, DNA Binding, and DNA Cleavage Activities.

The rutin-nickel (II) complex (RN) was synthesized and characterized by elemental analysis, UV-visible spectroscopy, IR, mass spectrometry, 1H NMR, TG-DSC, SEM, and molar conductivity. The low molar conductivity value investigates the non-electrolyte nature of the complex. The elemental analysis and other physical and spectroscopic methods reveal the 1:2 stoichiometric ratio (metal/ligand) of the complex. An antioxidant study of rutin and its metal complex against DPPH radical showed that the complex has more radical scavenging activity than free rutin. The interaction of complex RN with DNA was determined using fluorescence spectra and agarose gel electrophoresis. The results showed that RN can intercalate moderately with DNA, quench a strong intercalator ethidium bromide (EB), and compete for the intercalative binding sites. The complex showed significant cleavage of pBR 322 DNA from supercoiled form (SC) to nicked circular form (NC), and these cleavage effects were dose-dependent. Moreover, the mechanism of DNA cleavage indicated that it was a hydrolytic cleavage pathway. These results revealed the potential nuclease activity of the complex to cleave DNA.

Optimization of ultrasonic-assisted extraction of antioxidant polysaccharides from the stem of Trapa quadrispinosa using response surface methodology.

Response surface methodology (RSM) was used to optimize experimental conditions for ultrasonic-assisted extraction (UAE) of antioxidant crude polysaccharides (CPS) from Trapa quadrispinosa stems. Antioxidant capacity of polysaccharides was determined by Ferric-Reducing Antioxidant Capacity (FRAC) assay with the method of 1, 10-phenanthroline. The maximum yield of polysaccharides (2.78±0.16%) was obtained under optimal extraction conditions of extraction time, 41min; ratio of water to material, 31.5mL/g; and extraction temperature, 58°C. The maximum antioxidant capacity (19.02±0.24µmol Fe2+/g) was obtained under the optimal extraction conditions of extraction time, 38min; ratio of water to material, 32mL/g; and extraction temperature, 56°C. These two values were agreed well with predicted yield (2.75%) and antioxidant capacity (18.77µmol Fe2+/g). Antioxidant activities of CPS were investigated by various assays. The results showed that CPSUAE obtained by UAE showed higher 1,1-Diphenyl-2-picrylhydrazxyl (DPPH), 2,2-azinobis(3-ethylbenzthiazoline)-6-sulfonic acid (ABTS) radical scavenging activities and stronger reducing power, total antioxidant capacity compared with CPSHWE obtained by hot water extraction (HWE).The results indicated that UAE is an advisable method for extraction of antioxidant polysaccharides from the stem of T. quadrispinosa and polysaccharides could be explored as potential antioxidant to use in medicine or functional food.

Quercetin-Iron Complex: Synthesis, Characterization, Antioxidant, DNA Binding, DNA Cleavage, and Antibacterial Activity Studies.

Quercetin-iron (II) complex was synthesized and characterized by elemental analysis, ultraviolet-visible spectrophotometry, fourier transform infrared spectroscopy, mass spectrometry, proton nuclear magnetic resonance spectroscopy, thermogravimetry and differential scanning calorimetry, scanning electron micrography and molar conductivity. The low molar conductivity value investigates the non-electrolyte nature of the complex. The elemental analysis and other physical and spectroscopic methods reveal the 1:2 stoichiometric ratio (metal:ligand) of the complex. Antioxidant study of the quercetin and its metal complex against 2, 2-di-phenyl-1-picryl hydrazyl radical showed that the complex has much more radical scavenging activity than free quercetin. The interaction of quercetin-iron (II) complex with DNA was determined using ultraviolet visible spectra, fluorescence spectra and agarose gel electrophoresis. The results showed that quercetin-iron (II) complex can intercalate moderately with DNA, quench a strong intercalator ethidium bromide and compete for the intercalative binding sites. The complex showed significant cleavage of pBR 322 DNA from supercoiled form to nicked circular form and these cleavage effects were dose-dependent. Moreover, the mechanism of DNA cleavage indicated that it was an oxidative cleavage pathway. These results revealed the potential nuclease activity of complex to cleave DNA. In addition, antibacterial activity of complex on E.coli and S. aureus was also investigated. The results showed that complex has higher antibacterial activity than ligand.

[Plant regeneration from callus of Changiums myrnioides].

OBJECTIVE: To set up the callus culture system of Changiums myrnioides and the plantlet regeneration system by the proliferation and differentiation of callus. METHOD: The segment of stems used as the explants were cultured on dedifferentiation and differentiation medium supplied with different auxin and cytokinin. RESULT: MS medium with NAA 0.5 - 1.0 mg/L + KT 0.1 mg/L was best combination for the induction of callus, MS medium with 6 - BA 1 - 2 mg/L + GA 1 - 2 mg/L was suitable for the differentiation of adventitious buds, and MS medium with IBA 0.5 - 1 mg/L was suitable for the induction of root. CONCLUSION: Callus culture may be used as a useful method to get regenerated plantlet of Changiums myrnioides under certain condition.

[Establishment of plantlet regeneration system of medicinal plant Aconitum coreanum].

OBJECTIVE: To set up the rapid propagation and plantlet regeneration system of medicinal plant Aconitum coreanum (Levi.) Rpaics. METHOD: Adventitious buds and regenerated plantlet were obtained by shoot tip culture through different media and combination of plant growth regulators. RESULT: MS medium was the optimal medium for differentiation and proliferation of shoot tip. MS medium with 6-BA 2 to approximately 5 mg/L was found to be most suitable for the induction of bud. MS with 6-BA 2 mg/L + GA3 1 to approximately 5 mg/L or adenine 1 to approximately 5 mg/L was best combination for the growth and proliferation of adventitious buds, and MS with IBA 0.5 to approximately 1 mg/L for the induction of root. CONCLUSION: Tip culture may be used as a useful method to get regenerated plantlet of Aconitum coreanum under certain conditions.