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The aim of this paper was to obtain low toxicity and high efficiency anti-tumor Chinese medicine through screening the combination ratios of Momordicae Semen and Epimedii Folium, and to explore the anti-tumor mechanism of the combination of two drugs by observing their effect on apoptosis-related proteins in cancer cells. Methyl thiazolyl tetrazolium(MTT) assay was used to observe the effect of drug combination on the proliferation of tumor cells from different tissue sources. The effects of the combination of the two drugs on tumor cells were analyzed by Compusyn software. Plate cloning assay was used to observe the effect of combination of these two drugs on the proliferation of A549 cells in vitro. The expression of reactive oxygen species(ROS) and apoptotic proteins p53, Bcl-2 and Bax were compared by using ROS kit and Western blot. Lewis lung cancer model was used to observe the anti-tumor effect of drugs in vivo. The results showed that the anti-tumor effect of their ethanol extract was more significant than that of water extract, and the anti-proliferation effect was strongest when the ratio was 1â¶1(P<0.05). Compusyn analysis showed that the combination of the two drugs had synergistic effect. Further studies showed that after combined use, the number of clonogen formation in A549 cells was significantly reduced(P<0.01); ROS production was increased; the expression of apoptosis-related protein p53 was up-regulated, and the ratio of Bcl-2/Bax was decreased. In vivo animal study showed that the tumor inhibition rate was 53.06%(P<0.05) in the high dose group. As compared with the single use of the two drugs, the combination of the two drugs had more significant anti-proliferative effect on tumors, and the optimum ratio was 1â¶1. The combination of the two drugs at a ratio of 1â¶1 inhibited the proliferation of various tumor cells, and had no significant effect on normal liver cells LO2 when compared with other ratios. Therefore, it can be preliminarily inferred that the combination of the two drugs may have the effect of synergism and detoxification. Further studies showed that the combination of the two drugs can significantly inhibit the proliferation of A549 cells, and its mechanism may be related to the activation of endogenous apoptotic pathway. In vivo experiments also showed that the tumor inhibition rate increased with the increase of drug concentration.
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Antineoplásicos Fitogênicos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Epimedium/química , Neoplasias Pulmonares/tratamento farmacológico , Momordica/química , Células A549 , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Experimentais/tratamento farmacológico , Folhas de Planta/químicaRESUMO
Biochar is rich in both organic carbon and inorganic components. Extensive work has attributed the high sorption ability of biochar to the pore structure and surface chemical property related to its organic carbon fraction. In this study, three biochars derived from dairy manure (DM-biochar), sewage sludge (SS-biochar), and rice husk (RH-biochar), respectively, were evaluated for their SO2 sorption behavior and the underlying mechanisms, especially the role of inherent inorganic constituents. The sorption capacities of SO2 by the three biochars were 8.87-15.9 mg g-1. With the moisture content increasing from 0% to 50%, the sorption capacities increased by up to about 3 times, mainly due to the formation of alkaline water membrane on the biochar surface which could promote the sorption and transformation of acidic SO2. DM- and SS-biochar containing larger mineral constituents showed higher sorption capacity for SO2 than RH-biochar containing less mineral components. CaCO3 and Ca3(PO4)2 in DM-biochar induced sorbed SO2 transformation into K2Ca(SO4)2·H2O and CaSO4·2H2O, while the sorbed SO2 was converted to Fe2(SO4)3·H2SO4·2H2O, CaSO4·2H2O, and Ca3(SO3)2SO4·12H2O in SS-biochar. For RH-biochar, K3H(SO4)2 might exist in the exhausted samples. Overall, the chemical transformation of SO2 induced by biochar inherent mineral components occupied 44.6%-85.5% of the total SO2 sorption. The results obtained from this study demonstrated that biochar as a unique carbonaceous material could distinctly be a promising sorbent for acidic SO2 removal in which the inorganic components played an important role in the SO2 sorption and transformation.
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Biomassa , Carvão Vegetal/química , Adsorção , Carbono , Esterco , Esgotos/químicaRESUMO
Accurate acoustic source localization at a low sampling rate (less than 10 kHz) is still a challenging problem for small portable systems, especially for a multitasking micro-embedded system. A modification of the generalized cross-correlation (GCC) method with the up-sampling (US) theory is proposed and defined as the US-GCC method, which can improve the accuracy of the time delay of arrival (TDOA) and source location at a low sampling rate. In this work, through the US operation, an input signal with a certain sampling rate can be converted into another signal with a higher frequency. Furthermore, the optimal interpolation factor for the US operation is derived according to localization computation time and the standard deviation (SD) of target location estimations. On the one hand, simulation results show that absolute errors of the source locations based on the US-GCC method with an interpolation factor of 15 are approximately from 1/15- to 1/12-times those based on the GCC method, when the initial same sampling rates of both methods are 8 kHz. On the other hand, a simple and small portable passive acoustic source localization platform composed of a five-element cross microphone array has been designed and set up in this paper. The experiments on the established platform, which accurately locates a three-dimensional (3D) near-field target at a low sampling rate demonstrate that the proposed method is workable.
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The aim of this study was to explore the efficacy and safety of TGFß1 siRNA lipid nanoparticles (LNPs) modified with different PEG derivatives (PEG5000 cholesterol, abbreviated as CE; tocopherol polyethylene glycol 1000 succinate, abbreviated as TPGS) in the treatment of paclitaxel-resistant non-small-cell lung cancer. Three kinds of TGFß1 siRNA LNPs were prepared via microfluidics technology, using different PEG derivatives and dosages (CE1.5, CE2.5, TPGS2.5) as variables. Their particle size, zeta potential, contents, and encapsulation efficiencies were determined. The inhibition of TGFß1 mRNA and protein expression and the effects of the three kinds of LNPs on the proliferation of paclitaxel-resistant non-small-cell lung cancer cells (A549/T cell) were characterized. The distributions of the three siRNA LNPs in nude mice bearing A549/T tumors, especially at the tumor site, were observed using in vivo mouse imaging technology, and their corresponding efficacies were evaluated. The average particle size of the three kinds of TGFß1 siRNA LNPs was about 70-80 nm, and they were capable of charge flipping. All three siRNA LNPs could effectively inhibit the expression of TGFß1 mRNA and protein in A549/T cells and inhibit the proliferation of A549/T cells in vitro. The results of in vivo mice imaging showed that the three kinds of siRNA LNPs, when labeled with cypate, retain strong fluorescence in the tumor at 24 h. The pharmacodynamic results, such as for relative tumor volumes and tumor inhibition rates, reveal that TGFß1 siRNA LNPs modified with CE1.5, CE2.5, or TPGS2.5 can be used to effectively treat paclitaxel-resistant lung adenocarcinoma. The histopathological results showed that the three kinds of LNPs have a certain toxicity but are relatively safe compared to common forms of chemotherapy such as cabazitaxel. TGFß1 siRNA LNPs modified with CE1.5, CE2.5, and TPGS2.5 can inhibit TGFß1 mRNA and protein expression in A549/T cells in vitro and can accumulate and play a role in the tumor tissue of nude mice, features that can be exploited for treating paclitaxel-resistant lung adenocarcinoma.
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Plastic crystals as barocaloric materials exhibit the large entropy change rivalling freon, however, the limited pressure-sensitivity and large hysteresis of phase transition hinder the colossal barocaloric effect accomplished reversibly at low pressure. Here we report reversible colossal barocaloric effect at low pressure in two-dimensional van-der-Waals alkylammonium halides. Via introducing long carbon chains in ammonium halide plastic crystals, two-dimensional structure forms in (CH3-(CH2)n-1)2NH2X (X: halogen element) with weak interlayer van-der-Waals force, which dictates interlayer expansion as large as 13% and consequently volume change as much as 12% during phase transition. Such anisotropic expansion provides sufficient space for carbon chains to undergo dramatic conformation disordering, which induces colossal entropy change with large pressure-sensitivity and small hysteresis. The record reversible colossal barocaloric effect with entropy change ΔSr ~ 400 J kg-1 K-1 at 0.08 GPa and adiabatic temperature change ΔTr ~ 11 K at 0.1 GPa highlights the design of novel barocaloric materials by engineering the dimensionality of plastic crystals.
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Nuclear factor (NF)-κB plays a pivotal role in the regulation of inflammatory response in macrophages. Berberine (BBR), which is an active constituent isolated from Coptis rhizome, possesses a prominent anti-inflammatory activity. Here we show that BBR changes the global acetylation landscape in LPS-induced protein acetylation of macrophages and reduces the acetylation of NF-κB subunit p65 at site Lys310(p65Lys310), leading to the inhibition of NF-κB translocation and transcriptional activity to suppress the expressions of inflammatory factors. BBR resists the inflammatory response in acute LPS-stimulated mice through downregulation of p65Lys310 acetylation in peritoneal macrophages. In obese mice, BBR alleviates the metabolic disorder and inflammation with the reduced acetylation of p65Lys310 in white adipose tissue. Furthermore, we demonstrate that BBR acts as a regulator of p65Lys310 by inhibiting the expression of p300 in macrophages. Our findings elucidate a new molecular mechanism for the anti-inflammatory effect of BBR via the p300/p65Lys310 axis.
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Berberina , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Berberina/farmacologia , Berberina/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Acetilação , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Anti-Inflamatórios/farmacologiaRESUMO
The flows of people and material attributed to international tourism exert a major impact on the global environment. Tourism carbon emissions is the main indicator in this context. However, previous studies focused on estimating the emissions of destinations, ignoring the embodied emissions in tourists' origins and other areas. This study provides a comprehensive framework of a tourism telecoupling system. Taking China's international tourism as an example, we estimate the carbon emissions of its tourism telecoupling system based on the Tourism Satellite Account and input-output model. We find that (1) the proposal of a tourism telecoupling system provides a new perspective for analyzing the carbon emissions of a tourism system. The sending system (origins) and indirect spillover system (resource suppliers) have been ignored in previous studies. (2) In the telecoupling system of China's international tourism, the emission reduction effect of the sending system is significant. (3) The direct spillover system (transit) and indirect spillover system's spatial transfer effects of environment responsibility are remarkable. (4) There is a large carbon trade implied in international tourism. This study makes us pay attention to the carbon emissions of tourists' origins and the implied carbon trading in tourism flows.
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Carbono , Turismo , Dióxido de Carbono , HumanosRESUMO
Skeletal muscle is a principal tissue involved in energy expenditure and glucose metabolism. Although the results of our and other studies show that spexin could decrease food intake and obesity, the specific metabolic effect of spexin on glucose metabolism of skeletal muscle is still unclear. The aim of this study is to investigate whether spexin might mitigate obesity-induced insulin resistance in skeletal muscles and to explore its underlying mechanisms. The high fat diet-fed mice were treated with 50 µg/kg/d spexin for 21 consecutive days, and the differentiated myotubes of L6 were treated with spexin (200, 400, 800 nM) in the absence or presence of M871 (800 nM) for 12 h respectively. Besides, the galanin type 2 (GAL2) receptor knockdown myotubes were treated with 800 nM spexin for 12 h in this study. The present findings showed that spexin reversed hyperglycemia and glucose intolerance as well as insulin intolerance and insulin resistance in the mice fed with high fat diet. Furthermore, spexin markedly augmented the peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) expression and deacetylation, and further triggered glucose transporter 4 (GLUT4) expression and trafficking in myotubes through p38 mitogen-activated protein kinase (P38MAPK) and protein kinase B (AKT) activation. More importantly, the elevation of glucose consumption related genes by spexin were abolished by GAL2 receptor antagonist or silencing of GAL2 receptor in myotubes. In conclusion, our findings provide a novel insight that spexin can protect against insulin resistance and increase glucose consumption in skeletal muscles mainly through activation of GAL2/GLUT4 signal pathway. Spexin might therefore be a novel therapeutic target for hyperglycemia and insulin resistance in clinic.
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Resistência à InsulinaRESUMO
Aims/Introduction: Renal function impairment related to type 2 diabetes (T2DM) presents serious threat to public health. Previous studies suggest that vascular endothelial growth factor-B (VEGF-B) might contribute to renal injury. Therefore, this study investigated the association of serum VEGF-B level with the risk of renal function impairment in T2DM patients. Materials and Methods: Serum VEGF-B levels were measured in 213 patients with type 2 diabetes and 31 healthy participants. Participants with type 2 diabetes were further divided into a group of 112 participants with eGFR<90 mL/min/1.73m2 and 101 participants with eGFR≥ 90 mL/min/1.73m2. Clinical data were collected, and a binary logistic regression model was employed to test the association between potential predictors and eGFR. Results: Serum VEGF-B levels evaluated in type 2 diabetes patients compared with healthy controls. In patients with type 2 diabetes, serum VEGF-B level was positively correlated with triglyceride, serum creatinine and cystatin C while negatively correlated with HDL-C and eGFR. Binary logistic regression showed that serum VEGF-B level was an independent risk factor of eGFR<90 mL/min/1.73m2. Conclusions: Serum VEGF-B level is associated with renal function impairment in patients with type 2 diabetes and may be a potential drug target for diabetic kidney disease.
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Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Insuficiência Renal , Fator B de Crescimento do Endotélio Vascular , Nefropatias Diabéticas/etiologia , Taxa de Filtração Glomerular , Humanos , Rim/fisiologia , Fator B de Crescimento do Endotélio Vascular/sangueRESUMO
It was reported that spexin as an adipocyte-secreted protein could regulate obesity and insulin resistance. However, the specific metabolic contribution of spexin to fatty liver remains incompletely understood. Herein, we investigated the effects of spexin on hepatosteatosis and explored the underlying molecular mechanisms. HFD-fed mice were injected with spexin and/or GALR2 antagonist M871, while PA-induced HepG2 cells were treated with spexin in the absence or presence of M871 for 12 h, respectively. Gene expression in liver tissues and hepatocytes was assessed by qRT-PCR and western blotting, respectively. The results showed that body weight, visceral fat content, liver lipid droplet formation, hepatic intracellular triglyceride, and serum triglyceride were reduced in spexin-treated mice. Furthermore, spexin increased the expression of hepatic CPT1A, PPARα, SIRT1, KLF9, PGC-1α and PEPCK in vivo and in vitro. Additionally, spexin treatment improved glucose tolerance and insulin sensitivity in mice fed the HFD. Interestingly, these spexin-mediated beneficial effects were abolished by the GALR2 antagonist M871 in mice fed HFD and PA-induced HepG2 cells, suggesting that spexin mitigated HFD-induced hepatic steatosis by activating the GALR2, thereby increasing CPT1A, PPARα, SIRT1, KLF9, PGC-1α and PEPCK expression. Taken together, these data suggest that spexin ameliorates NAFLD by improving lipolysis and fatty acid oxidation via activation of GALR2 signaling.
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Resistência à Insulina , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Hormônios Peptídicos/farmacologia , Ração Animal , Animais , Dieta Hiperlipídica , Resistência à Insulina/fisiologia , Fígado/metabolismo , Cirrose Hepática/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Receptor Tipo 2 de Galanina/metabolismo , Sirtuína 1/metabolismo , Triglicerídeos/metabolismoRESUMO
Background: Ginsenoside Rb1 (GRb1) is capable of regulating lipid and glucose metabolism through its action on adipocytes. However, the beneficial role of GRb1-induced up-regulation of adiponectin in liver steatosis remains unelucidated. Thus, we tested whether GRb1 ameliorates liver steatosis and insulin resistance by promoting the expression of adiponectin. Methods: 3T3-L1 adipocytes and hepatocytes were used to investigate GRb1's action on adiponectin expression and triglyceride (TG) accumulation. Wild type (WT) mice and adiponectin knockout (KO) mice fed high fat diet were treated with GRb1 for 2 weeks. Hepatic fat accumulation and function as well as insulin sensitivity was measured. The activation of AMPK was also detected in the liver and hepatocytes. Results: GRb1 reversed the reduction of adiponectin secretion in adipocytes. The conditioned medium (CM) from adipocytes treated with GRb1 reduced TG accumulation in hepatocytes, which was partly attenuated by the adiponectin antibody. In the KO mice, the GRb1-induced significant decrease of TG content, ALT and AST was blocked by the deletion of adiponectin. The elevations of GRb1-induced insulin sensitivity indicated by OGTT, ITT and HOMA-IR were also weakened in the KO mice. The CM treatment significantly enhanced the phosphorylation of AMPK in hepatocytes, but not GRb1 treatment. Likewise, the phosphorylation of AMPK in liver of the WT mice was increased by GRb1, but not in the KO mice. Conclusions: The up-regulation of adiponectin by GRb1 contributes to the amelioration of liver steatosis and insulin resistance, which further elucidates a new mechanism underlying the beneficial effects of GRb1 on obesity.
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Salvianolic acid B (Sal B) has strong antioxidant and anti-fibrosis effects, which are related to the transforming growth factor ß/Smad signaling pathway. However, how Sal B affects this antioxidant pathway and the phosphorylation (p-) of Smad2 at both the COOH-terminal (pSmad2C) and linker region (pSmad2L) are unknown. The aims of the present study were to investigate the underlying mechanisms of Sal B on acute and chronic liver injury induced by CCl4 and H2O2, and its effects on p-Smad2C/L. In in vivo experiments, acute and chronic liver injury models were induced by CCl4, and the oxidative damage cell model was established in vitro with H2O2. Liver histopathology was assessed using hematoxylin and eosin and Van Gieson's staining. Moreover, serum biochemical indicators were analyzed using specific assay kits. Furthermore, the present study evaluated the oxidant/antioxidant status in acute and chronic liver injury models by oxidative stress parameters such as malondialdehyde, glutathione and superoxide dismutase. In addition, western blot analysis was performed to analyze the protein expression levels of pSmad2C, pSmad2L, nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). It was found that Sal B improved liver histology, decreased the levels of aminotransferase and attenuated oxidative stress in acute and chronic liver injury models. Additionally, the protein expression levels of pSmad2C and pSmad2L were decreased, but Nrf2 and HO-1 expression levels were increased both in vivo and in vitro. Collectively, the present results suggested that Sal B may protect against acute and chronic liver injury via inhibition of Smad2C/L phosphorylation, and the Nrf2/HO-1 signaling pathway may play an important role in this process.
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Microbial degradation is an elimination method for removal of organic contaminants from soil and water. However, the main factor limiting its practical application is high bacterial sensitivity to environmental factors such as pH, toxicity, and mass transfer. In this study, biochar was produced pyrolytically from peanut shells at 350 °C, 550 °C, and 750 °C (referred to as BC350, BC550, and BC750, respectively) and their promotion on phenol biodegradation in wastewater by the bacterium Pseudomonas citronellolis was investigated. Higher initial phenol concentration (>400 mg L-1) showed obvious inhibition on biodegradation with the removal efficiencies being less than 46%, and even the bacterium failed to survive at the phenol concentrations of higher than 1000 mg L-1. With biochar incorporated, the removal efficiencies of phenol increased from below 46% to up to 99% at the initial concentrations of 400-1200 mg L-1. Immobilization of strains in biochar by calcium alginate further increased the microbial tolerance to high concentrations of phenol (i.e., 63% removal at 1200 mg L-1). Scanning electron microscopy demonstrated that biochar acted as shelter to support the bacterium to struggle with extreme conditions. The initial adsorption of phenol by biochar alleviated the initial toxicity of phenol to bacterium and the subsequent gradual desorption controlled the bioavailability of phenol. In this regard, BC350 showed a comparable sorption capacity with BC550 and BC750, while a higher desorption potential than them, thus balanced better the toxicity and bioavailability of phenol to microbes. Alkalinity of BC550 and BC750 played important roles in rescuing the microbes from being damaged by pH shock via neutralizing the fast generation of acidic intermediates. The extractable organic substances in BC350 could be consumed by bacterium as substrates, which was confirmed by incubating the strains in water-extractable solution. Results of this study indicate that incorporation of microbes with biochar could promote the biodegradation of high concentration organic wastewater.
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Fenol , Águas Residuárias , Adsorção , Biodegradação Ambiental , Carvão Vegetal , Concentração de Íons de Hidrogênio , Fenóis , PseudomonasRESUMO
BACKGROUND: To evaluate RV-PA coupling in post operative TOF patients with ventricular dilatation underwent for PVR and investigate the correlation between ventricular functions measuring Ea/Emax ratio using cardio magnetic resonance and the effect of surgical type at primary repair of TOF on coupling. METHOD: RV-PA coupling was measured noninvasively by Ea/Emax ratio from CMRI and ECHO. From CMRI results the patients were divided in two groups, RV-PA coupling and RV-PA uncoupling. Ea/Emax ≤1 was considered for coupling patients and Ea/Emax > 1 for uncoupling patients. RESULTS: Ninety patients were uncoupled (Ea/Emax: 1.55 ± 0.46) and 45 were coupled (Ea/Emax: 0.81 ± 0.15). Out of 75 TAP repaired patients 60 were uncoupled RV-PV. In addition, higher pro-BNP is an important factor for uncoupled RV-PV (P = 0.001). CMR evaluation for right ventricular function between uncoupling and coupling were RVEDVi (196.65 ± 63.57 vs. 154.28 ± 50.07, P = 0.001), RVESVi (121.19 ± 51.47 vs. 83.94 ± 20.43, P = 0.001), RVSVi (67.19 ± 19.87 vs. 106.31 ± 33.44, P = 0.001), and RVEF (40.90 ± 8.73 vs. 54.63 ± 4.76, P = 0.001). The increased RVEDVi, RVESVi and RVSVi and decreased RVEF have significant correlation with Ea/Emax. Ea/Emax was also found positively correlated with RVEDVi (P = < 0.05, r = 0.35), RVESVi (P = < 0.001, r = 0.41) and negatively correlated with RVSVi (P = < 0.05, r = 0.22) and RVEF (P = < 0.05, r = 0.78). CONCLUSIONS: Unfavorable RV-PA coupling is present in post operative TOF patients and it is affected by several factors. Our results explain a new concept of RV-PA interactions as a contributing mechanism for the observed decline in RV function.
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Implante de Prótese de Valva Cardíaca , Artéria Pulmonar/cirurgia , Valva Pulmonar/cirurgia , Tetralogia de Fallot/cirurgia , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Direita , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Período Pós-Operatório , Insuficiência da Valva Pulmonar/cirurgia , Estudos Retrospectivos , Adulto JovemRESUMO
Biochar as a porous carbon material could be used for improving soil physical and chemical properties, while insufficient attention has been paid to potential risks induced by infiltration of heavy metals in the runoff water flowing through biochar-amended soil. Four different soil-biochar matrices with same volumes were constructed including soil alone (M1), biochar alone (M2), soil-biochar layering (M3) and soil-biochar mixing (M4). Leaching experiments were conducted with Pb, Cu, and Zn contaminated runoff water. Results showed that biochar amendment greatly improved the water permeation, and the infiltration rates in M2, M3, and M4 were 2.85-23.0â¯mmâ¯min-1, being much higher than those in M1 (1.33-4.05â¯mmâ¯min-1), though the rates decreased as the leaching volumes increased. However, biochar induced more Pb, Cu, and Zn infiltrated through soil-biochar matrix. After 350-L leaching, M1 retained about 95% Pb, 90% Cu, and 36% Zn, while M2 only retained 4.80% Pb, 17.4% Cu, and 4.01% Zn; about 30% Pb, 80% Cu, and 15% Zn were retained in M3 and M4. Notably, Zn was trapped first and then re-leached into the filtrate, which resulted in a much higher effluent Zn than the influent Zn at the later stage. However, the unit weight of biochar showed a higher capacity for retaining heavy metals compared to per unit of soil. Under the dynamic water flow, all benefits and disadvantages induced by biochar were weakened with its physical disintegration. Biochar as soil amendment can enhance plant growth via ameliorating soil structure, while it would pose risks to environment because of large penetration of heavy metals. If biochar was compacted to form a denser physical structure, perhaps more heavy metals could be retained.
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Carvão Vegetal , Metais Pesados/química , Poluentes do Solo/química , Solo/química , Água SubterrâneaRESUMO
MicroRNAs 21 and 145 exhibit inverse expression in Hepatocellular carcinoma (HCC), but how they relate to Smad3 C-terminal and Link region phosphorylation (pSmad3C and pSmad3L) downstream of TGF-ß/MAPK signaling, remains inconclusive. Our results suggest microRNA-145 targets Smad3 in HepG2 cells. Decreased tumor volume and increased apoptosis were produced in both microRNA-21 antagomir and microRNA-145 agomir groups compared to controls. Inhibition of TßRI and MAPK (ERK, JNK, and p38) activation respectively produced decreased microRNA-21 but increased microRNA-145 expression. Correspondingly, the expression level of pSmad3C obviously increased while pSmad3L decreased in microRNA-145 agomir-group and the expression of pSmad3C/3L were not markedly changed but pERK, pJNK, pp38 decreased in microRNA-21 antagomir-group compared to controls. On the other hand, microRNA-145 and 21 increased respectively in xenografts of HepG2 cells transfected with Smad3 EPSM and 3S-A plasmid, and this correlated with the overexpression of pSmad3C and pSmad3L respectively compared to control. To conclude, microRNA-21 promotes tumor progression in a MAPK-dependent manner while microRNA-145 suppresses it via domain-specific phosphorylation of Smad3 in HCC. Meanwhile, increased pSmad3C/3L lead to the up-regulation of microRNA-145/21 respectively. The interaction between pSmad3C/3L and microRNA-145/21 regulates HCC progression and the switch of pSmad3C/3L may serve as an important target for HCC therapy.
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Biochar is a porous carbonaceous material with high alkalinity and rich minerals, making it possible for CO2 capture. In this study, biochars derived from pig manure, sewage sludge, and wheat straw were evaluated for their CO2 sorption behavior. All three biochars showed high sorption abilities for CO2, with the maximum capacities reaching 18.2-34.4 mg g(-1) at 25 °C. Elevating sorption temperature and moisture content promoted the transition of CO2 uptake from physical to chemical process. Mineral components such as Mg, Ca, Fe, K, etc. in biochar induced the chemical sorption of CO2 via the mineralogical reactions which occupied 17.7%-50.9% of the total sorption. FeOOH in sewage sludge biochar was transformed by sorbed CO2 into Fe(OH)2CO3, while the sorbed CO2 in pig manure biochar was precipitated as K2Ca(CO3)2 and CaMg(CO3)2, which resulted in a dominant increase of insoluble inorganic carbon in both biochars. For wheat straw biochar, sorbed CO2 induced CaCO3 transformed into soluble Ca(HCO3)2, which led to a dominant increase of soluble inorganic carbons. The results obtained from this study demonstrated that biochar as a unique carbonaceous material could distinctly be a promising sorbent for CO2 capture in which chemical sorption induced by mineralogical reactions played an important role.
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Dióxido de Carbono/química , Carvão Vegetal/química , Minerais/química , Adsorção , Animais , Umidade , Concentração de Íons de Hidrogênio , Esterco/análise , Esgotos/análise , Silagem/análise , Sus scrofa , Temperatura , TriticumRESUMO
There is often over 50% carbon loss during the thermal conversion of biomass into biochar, leading to it controversy for the biochar formation as a carbon sequestration strategy. Sometimes the biochar also seems not to be stable enough due to physical, chemical, and biological reactions in soils. In this study, three phosphorus-bearing materials, H3PO4, phosphate rock tailing (PRT), and triple superphosphate (TSP), were used as additives to wheat straw with a ratio of 1: 0.4-0.8 for biochar production at 500°C, aiming to alleviate carbon loss during pyrolysis and to increase biochar-C stabilization. All these additives remarkably increased the biochar yield from 31.7% (unmodified biochar) to 46.9%-56.9% (modified biochars). Carbon loss during pyrolysis was reduced from 51.7% to 35.5%-47.7%. Thermogravimetric analysis curves showed that the additives had no effect on thermal stability of biochar but did enhance its oxidative stability. Microbial mineralization was obviously reduced in the modified biochar, especially in the TSP-BC, in which the total CO2 emission during 60-d incubation was reduced by 67.8%, compared to the unmodified biochar. Enhancement of carbon retention and biochar stability was probably due to the formation of meta-phosphate or C-O-PO3, which could either form a physical layer to hinder the contact of C with O2 and bacteria, or occupy the active sites of the C band. Our results indicate that pre-treating biomass with phosphors-bearing materials is effective for reducing carbon loss during pyrolysis and for increasing biochar stabilization, which provides a novel method by which biochar can be designed to improve the carbon sequestration capacity.