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1.
J Hazard Mater ; 382: 121071, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472466

RESUMO

Effects of biotic aging on the characteristics of biochar and its water-soluble organic products were determined through a one-year laboratory incubation study. Biochar had a positive influence on microbial population size. Without microbial addition, biochars showed little change, except for an obvious increase in oxygen content from 3.2% to 6.3% after one year. By contrast, the carbon (C) content of the biologically-aged biochars continually decreased throughout the incubation at two humidity levels, suggesting that microbes consumed biochar C or encouraged organic matter solubilization. Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated that all aged biochar surfaces showed increases in oxygen-containing functional groups and TG-DTG analysis showed that biologically-aged biochars were less stable than the corresponding abiotically-aged one. The release of dissolved organic matters from biologically-aged biochar logarithmically increasing with time, corresponded with of the pattern of microbe production, suggesting microbial involvement in solubilizing biochar. Combined three-dimensional excitation-emission matrix (3DEEM) and parallel factor (PARAFAC) analyses revealed that fulvic and humic acid-like components were the main water-soluble products of biologically-aged biochar, and these became increasingly rich in O-containing functional groups, i.e. humified, over time. These results highlight the importance of microbes in chemically transforming biochar and the dissolved products of biochar during aging.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31673917

RESUMO

Chromium (Cr) is a common environmental contaminant due to industrial processes and anthropogenic activities such as mining of chrome ore, electroplating, timber treatment, leather tanning, fertilizer and pesticide, etc. Cr exists mainly in both hexavalent [Cr(VI)] and trivalent [Cr(III)] form, being Cr(VI) with non-degradability and potential to be hidden, thereby affecting surrounding environment and being toxic to human health. Therefore, researches on remediation of Cr pollution in the environment have received much attention. Biochar is a low-cost adsorbent, which has been identified as a suitable material for Cr(VI) immobilization and removal from soil and wastewater. This review incorporates existing literature to provide a detailed examination into the (1) Cr chemistry, the source and current status of Cr pollution, and Cr toxicity and health; (2) feedstock and characterization of biochar; (3) processes and mechanisms of immobilization and removal of Cr by biochar, including oxidation-reduction, electrostatic interactions, complexation, ion exchange, and precipitation; (4) applications of biochar for Cr(VI) remediation and the modification of biochar to improve its performance; (5) factors affecting removal efficiency of Cr(VI) with respect to its physico-chemical conditions, including pH, temperature, initial concentration, reaction time, biochar characteristics, and coexisting contaminants. Finally, we identify current issues, challenges, and put forward recommendations as well as proposed directions for future research. This review provides a thorough understanding of using biochar as an emerging biomaterial adsorbent in Cr(VI)-contaminated soils and wastewater.

3.
Proc Natl Acad Sci U S A ; 116(48): 23947-23953, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31712425

RESUMO

The Arctic has warmed significantly since the early 1980s and much of this warming can be attributed to the surface albedo feedback. In this study, satellite observations reveal a 1.25 to 1.51% per decade absolute reduction in the Arctic mean surface albedo in spring and summer during 1982 to 2014. Results from a global model and reanalysis data are used to unravel the causes of this albedo reduction. We find that reductions of terrestrial snow cover, snow cover fraction over sea ice, and sea ice extent appear to contribute equally to the Arctic albedo decline. We show that the decrease in snow cover fraction is primarily driven by the increase in surface air temperature, followed by declining snowfall. Although the total precipitation has increased as the Arctic warms, Arctic snowfall is reduced substantially in all analyzed data sets. Light-absorbing soot in snow has been decreasing in past decades over the Arctic, indicating that soot heating has not been the driver of changes in the Arctic snow cover, ice cover, and surface albedo since the 1980s.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31713412

RESUMO

Metal-organic frameworks (MOFs) are powerful toolkits to directly correlate structure-function relationships due to their well-defined structures. In this work, 5,15-di(3,4,5-trihydroxyphenyl)porphyrin (DTPP) and 5,10,15,20-tetra(3,4,5-trihydroxyphenyl)porphyrin (TTPP) are reacted with zirconium ions to afford two MOFs (Zr-DTPP and Zr-TTPP) with acid and base tolerance in the pH range of 1.0-14.0. Powder X-ray diffraction investigation combined with Rietveld refinement reveals the J-aggregated porphyrin building blocks confined by benzene-1,2,3-trisolate-zirconium chains in the newly prepared Zr-DTPP. Electron spin-resonance, singlet-oxygen determination, and sulfides oxidation experiments demonstrate a much better singlet-oxygen evolution of J-aggregated Zr-DTPP than that of unaggregated Zr-TTPP reported previously, in good contrast to the weaker photocatalytic capability disclosed for DTPP than that for TTPP in solution, consummating the theory of photosensitizer J-aggregation in boosting heterogeneous photoinduced singlet-oxygen generation.

5.
Sci Total Environ ; 701: 134919, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31726408

RESUMO

Multiple spectroscopic technologies and chemometric analyses were combined to explore the compositional characteristics and Cu binding performance of biochar-derived dissolved organic matter (DOM). The DOM samples were extracted from biochars produced from lignocellulose-rich rapeseed cake (RSC) by pyrolysis at 300, 500, and 700 °C (i.e., RSC300, RSC500, RSC700). Fourier transform infrared spectroscopy (FTIR) and carbon K-edge near-edge X-ray absorption fine structure spectroscopy (NEXAFS) analyses were combined to elucidate the molecular-level C species in the DOM. With the increasing pyrolysis temperature, DOM aromaticity increased, whereas the proportion of metal complexing sites (e.g., carboxyl and phenolic groups) decreased. Fluorescence excitation-emission matrix (EEM) spectroscopy with parallel factor analysis (PARAFAC) indicated that biochar DOM, irrespective of pyrolysis temperature, was mostly composed of three types of humic-like components (C1-C3), and a small amount of a protein-like component (C4). As charring temperature increased, DOM concentrations decreased substantially, but the humic-like C3 with abundant aromatic structures became predominant. Fluorescence quenching experiment and two-dimensional correlation spectroscopy (2D-COS) analysis suggested that the preferential Cu(II) binding fractions of the DOM were the humic-like substances. Moreover, the quenching curve fitting results for individual components indicated that despite the Cu(II) binding affinity was slightly enhanced as the pyrolysis temperature increased, the binding capacities of the four components decreased. In general, the DOM components from RSC biochar exhibited limited Cu(II) binding capacities (2.18-17.7 µmol L-1). Results from this study improved understanding of the mechanisms by which biochar DOM interacts with Cu, and provided tools for fast screening of biochars to reduce their environmental risks.

6.
Cancer Lett ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31765737

RESUMO

Most cancers are caused by somatic mutations. Some common mutations in the same cancer type can form a "signature" to specifically predict the prognosis or to distinguish it from other cancers. In this study, 710 somatic cell mutations were identified in 142 cases, including digestive, lung and urogenital cancers, and the digestive cancers were further divided into liver, stomach, intestinal, esophageal and cardia cancer. The above mutations were located in 166 genes. In addition, a group of high-frequency mutation genes with specific characteristics were screened to form predictive signatures for each cancer. Verification using TCGA suggested that the signatures could predict the stages, progression-free survival, and overall survival of digestive, intestinal, and liver cancers (P<0.05). The validation cases further confirmed the predictive role of digestive and liver cancers signatures in diagnosis and prognosis. Overall, this study established predictive signatures for different cancer systems and their subtypes. These findings enable a better understanding in cancer genome, and contribute to the personalized diagnosis and treatment.

7.
Sci Total Environ ; 702: 134878, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31726350

RESUMO

Sorption of organic contaminants by biochar greatly affects their bioavailability and fate in soils. Nevertheless, very little information is available regarding the effects of biochar on sorption and desorption of organic contaminants in different soil particle-size fractions. In this study, di-n-butyl phthalate (DBP), a prevalent organic contaminant in agricultural soils, was taken as a model contaminant. The effects of biochar on DBP sorption and desorption in six particle-size fractions (i.e., coarse sand, fine sand, coarse silt, fine silt, clay, and humic acid fractions) of paddy soil were investigated using batch sorption-desorption experiments. A straw-derived biochar with high specific surface area (116 m2/g) and high content of organic matter (OM) rich in aromatic carbon (67%) was prepared. Addition of this biochar (1% and 5%) significantly promoted the sorption and retention of DBP in all the paddy soil particle-size fractions at environmentally relevant DBP concentrations (2-12 mg/L) with 1.2-132-fold increase of the Kd values. With increasing addition rates of biochar, DBP retention by the biochar enhanced. The biochar's effectiveness was remarkably influenced by the physicochemical properties of the soil particle-size fractions, especially, the OM contents and pore size showed the most striking effects. A parameter (rkd) reflecting the biochar's effectiveness showed negative and positive correlations with OM contents and pore size of the soil particle-size fractions, respectively. Accordingly, strong effect of the biochar was found in the soil fractions with low OM contents and high pore size. The findings of this study gave insight into the effects and influencing factors of biochar on sorption and desorption of organic contaminants in soils at scale of various particle-size factions.

8.
Environ Pollut ; : 113541, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31761593

RESUMO

Deposition of light-absorbing particles on glacier surfaces poses a series of adverse impacts on the cryospheric environment, climate and human health. Broad attention of the scientific community has been paid on insoluble light-absorbing impurities (ILAIs) in snow and ice on glaciers over the Tibetan Plateau (TP). However, systematic investigation of ILAIs in snowpack of glaciers on the TP is scarce. In this study, the properties and darkening effect of ILAIs in snowpack on glaciers are extensively investigated in the southeast of TP. Results show that ILAIs concentrations in multiple types of snow and ice samples were significantly different. Snowpit depths varied substantially from one profile to another during May and June 2016. The average concentrations of ILAIs in snowpits increase as snow melting progresses. Black carbon (BC) and dust cause snow albedo reduction more in snow with larger grain size Re. Based on a radiative transfer model calculation, the average albedo reduction induced by BC in the snowpack was 0.141 ± 0.02, and associated daily maximum radiative forcing (RF) was 72.97 ± 12.7 W m-2. BC is a controlling light-absorbing factor in snowpack and causes substantial albedo reduction and thus the associated daily maximum RF. The maximum reduction of snow cover duration was 4.56 ± 0.71 days caused by BC and dust in snowpack in southeastern TP. The average mass absorption cross-section (MAC) of BC from multiple snowpits was 3.26 ± 0.46 m2 g-1, which represents a typical value of MAC in snow on glaciers, but it is type-dependent of snow/ice samples. Tropospheric aerosols vertically extended up to 8 km over the TP and its surrounding areas, which indicates the transport of aerosols from remote sources through elevated pathways. A large amount of carbon stored in the brittle glaciers can be potentially released with meltwater runoff under a warming climate. This study provides a new insight for investigating carbonaceous and light-absorbing particles in glacierization areas.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31718976

RESUMO

A novel fluorescent biosensor based on dabcyl [(E)-4-((4-(dimethylamino) phenyl) diazenyl)benzoic acid] -modified anti-Mb aptamer (D-AMA) and 6-FAM(6-carboxyfluorescein) -modified complementary short chain (F-CSC)for the specific and sensitive detection of Mb levels is presented in this study. In PBS buffer solution, D-AMA bound to F-CSC, and then dabcyl quenched the fluorescence of 6-FAM. After adding Mb into the system, D-AMA bound to Mb and separated from F-CSC. The fluorescence of 6-FAM was restored after it separated from dabcyl. The assay exhibited high specificity and sensitivity toward Mb, with a low limit of detection of 0.07 ng/mL (S/N = 3) and linear relationships of 0.1-5 ng/mL. It was further applied to detect Mb levels in spiked human blood sera samples.

10.
J Hazard Mater ; 384: 121265, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31581012

RESUMO

Long-term studies on the environmental effects following biochar additions to soils, while plentiful, are predominantly focused on the soil fertility, whereas few are on the soil organo-mineral complexes. This study examines the changes of organo-mineral complexes in an acidic paddy soil and a saline-alkali soil which were remediated using biochar for approximately 8 years and 3 years, respectively. The results showed that loosely combined humus increased by 30.1% and 25.1% with the application of 40 t ha-1 biochar in the acidic paddy soil and the saline-alkali soil, respectively. Meanwhile, an increase of cement (Fe-oxides) was the contributor to the rise of the complexes content. Complex iron in the saline-alkali soil were 30% higher than in the acidic paddy soil with the application of 40 t ha-1 biochar. Fourier Transform Infrared Spectroscopy showed oxygen-containing functional groups on the surface of the biochar separated from the remediated field. X-ray diffraction analysis indicated that both complexation and sedimentation were involved in heavy metal immobilization. It was found that biochar amendment mitigated the effect of acid rain leaching and reduced vertical migration of the Fe/Al-bound complex, which can prevent soil from podzolization and thus improve its fertility.

11.
Dalton Trans ; 48(42): 15970-15976, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31595278

RESUMO

The potential of metal ß-diketonate complexes for the catalysis of the chemical fixation of CO2 into cyclic carbonates at 1 atm CO2 and near room temperature was demonstrated. Their potential for the capture and simultaneous conversion of CO2 in a dilute CO2 stream was also determined. The catalysts were easily synthesized and commercially available. Therefore, this CO2 transformation was less energy- and material-consuming, which made this reaction closer to true "green" chemistry.

12.
Circ J ; 83(12): 2537-2546, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31645525

RESUMO

BACKGROUND: Given that cathepsin S (CatS) gained attention due to its enzymatic and non-enzymatic functions in signaling, the role of CatS in ischemia-induced angiogenesis of aged mice was explored.Methods and Results:To study the role of CatS in the decline in aging-related vascular regeneration capacity, a hindlimb ischemia model was applied to aged wild-type (CatS+/+) and CatS-deficient (CatS-/-) mice. CatS-/-mice exhibited impaired blood flow recovery and capillary formation and increased levels of p-insulin receptor substrate-1, Wnt5a, and SC35 proteins and decreased levels of phospho-endothelial nitric oxide synthase (p-eNOS), p-mTOR, p-Akt, p-ERK1/2, p-glycogen synthase kinase-3α/ß, and galatin-3 proteins, as well as decreased macrophage infiltration and matrix metalloproteinase-2/-9 activities in the ischemic muscles. In vitro, CatS knockdown altered the levels of these targeted essential molecules for angiogenesis. Together, the results suggested that CatS-/-leads to defective endothelial cell functions and that CatS-/-is associated with decreased circulating endothelial progenitor cell (EPC)-like CD31+/c-Kit+cells. This notion was reinforced by the study finding that pharmacological CatS inhibition led to a declined angiogenic capacity accompanied by increased Wnt5a and SC35 levels and decreased eNOS/Akt-ERK1/2 signaling in response to ischemia. CONCLUSIONS: These findings demonstrated that the impairment of ischemia-induced neovascularization in aged CatS-/-mice is due, at least in part, to the attenuation of endothelial cell/EPC functions and/or mobilization associated with Wnt5a/SC35 activation in advanced age.

13.
Chem Biol Interact ; 314: 108842, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31586451

RESUMO

BACKGROUND AND AIMS: Chronic psychosocial stress is a risk factor for cardiovascular disease. In view of the important role of dipeptidyl peptidase-4 (DPP-4) in human pathophysiology, we studied the role of DPP-4 in stress-related vascular aging in mice, focusing on oxidative stress and the inflammatory response. METHODS AND RESULTS: Male mice were randomly divided into a non-stress group and an immobilization stress group treated for 2 weeks. Chronic stress accelerates aortic senescence and increases plasma DPP-4 levels. Stress increased the levels of gp91phox, p22phox, p47phox, p67phox, p53, p27, p21, p16INK4A, vascular cell adhesion molecule-1, intracellular adhesion molecule-1, monocyte chemoattractant protein-1, matrix metalloproteinase-2 (MMP-2), MMP-9, cathepsin S (Cat S), and Cat K mRNAs and/or protein in the aorta of the stressed mice and decreased their levels of endothelial nitric oxide synthase and SirTuin1 (SirT1). DPP-4 inhibitors can improve stress-induced targeting molecules and morphological changes. In vitro, the inhibition of DPP-4 also alleviated the changes in the oxidative and inflammatory molecules in response to hydrogen peroxide in human umbilical vein endothelial cells. CONCLUSIONS: DPP-4 inhibition can improve vascular aging in stressed mice, possibly by improving oxidative stress production and vascular inflammation. Our results suggest that DPP-4 may become a new therapeutic target for chronic stress-related vascular aging in metabolic cardiovascular diseases.


Assuntos
Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Aorta/metabolismo , Aorta/patologia , Dipeptidil Peptidase 4/sangue , Dipeptidil Peptidase 4/química , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Peróxido de Hidrogênio/metabolismo , Inflamação/patologia , Inflamação/prevenção & controle , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Pirimidinas/farmacologia , Sirtuína 1/metabolismo , Estresse Fisiológico
14.
Chemosphere ; 241: 125004, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31590025

RESUMO

A simple foaming method was applied to fabricate urea formaldehyde (UF) microspheres with cross-linked porous structures for environmental remediation of heavy metals. The specific surface area and average pore radius of the resultant foamed UF microspheres were 11-29 m2/g and 11-25 nm, respectively, which increased with the increasing molar ratio of formaldehyde to urea. All the foamed UF microspheres showed good removal of heavy metals ions (Pb(II), Cu(II), and Cd(II)) in both single- and mixed-metal solutions. Further investigations of Pb(II) adsorption on a selected UF microspheres showed fast kinetics and relatively high adsorption capacity (21.5 mg/g), which can be attributed to the mesoporous structure and abundance of oxygen surface functional groups of the microspheres. Both experimental and model results showed that chelation or complexation interactions between Pb(II) and the surface functional groups were responsible to the strong adsorption of the heavy metal ions on the microspheres. Hydrochloric acid (0.05 M) successfully desorbed Pb(II) from the post-adsorption microspheres for multiple times and the regenerated microspheres showed high Pb(II) removal rates (>96%) in five adsorption-desorption cycles. With many promising advantages, foamed UF microspheres show great potential as a wastewater treatment agent for heavy metal removal.

15.
Chemosphere ; 241: 124888, 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31606574

RESUMO

Effective soil phosphorus (P) management requires higher level of knowledge concerning its sorption-desorption, fractionation, and release, as well as its interactions with soil amendments including biochar (BC). The purpose of this research was to investigate the influence of two different BCs, derived from almond and walnut shell, on P sorption-desorption and its redistribution among the geochemical fractions in two different soils. The BCs were applied to the soils in four doses (0, 2.5, 5, and 10% w/w) and the mixtures were incubated for one month. Phosphorus sorption increased due to the addition of BCs. Phosphorus sorption data fitted well the Freundlich isotherm and were simulated by the PHREEQC software. Biochar addition increased total P and the added P was mainly distributed in the exchangeable, Fe/Al-P and the residual fractions. Also, BC addition resulted in an increase in the water-soluble-, mobile-, and Olsen-P, making P more available for plant uptake. The kinetics data were well described by the simple Elovich, pseudo-second-order, and intra-particle diffusion equations. Walnut BC-added soils had higher P sorption capacity than those added with the almond BC. The results suggest that BC binds soil P and releases it gradually back into solution, making it thus available to plants; this renders the studied BCs promising materials for protecting P from being lost out of soil. Future research must be conducted over longer-term experiments that would study P dynamics in BC-added soils under real field conditions.

16.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3358-3364, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602895

RESUMO

To evaluate the effect of Tripterygium Glycosides Tablets extract in the treatment of rheumatoid arthritis( RA). Clinical trials of treating rheumatoid arthritis with Tripterygium Glycosides Tablets published by Meta-analysis were retrieved from EMbase,PubMed,Clinical Trials,Web of Science,Cochrane Library,CNKI,Wanfang,VIP,CBM and Chi CTR,and comprehensively analyzed. A total of 3 studies were enrolled,the modified Sharp score( m TSS),tender join joint erosions( JE) and joint space narrowing( JSN) of Tripterygium Glycosides Tablets group were significant superior to those of control group,including positive drugs methotrexate( MTX) and salazopyridine( SSZ)( P<0. 01). Tripterygium Glycosides Tablets had an effect in treating RA. Due to the small sample size,this study shall be verified with high-quality,large-sample-size double-blinded RCTs.


Assuntos
Antirreumáticos/farmacologia , Artrite Reumatoide/tratamento farmacológico , Glicosídeos/farmacologia , Tripterygium/química , Humanos , Comprimidos
17.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3415-3422, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602903

RESUMO

Growing clinical evidence shows that a partial rheumatoid arthritis( RA) patient treated with Tripterygium Glycosides Tablets( TGT) may fail to achieve clinical improvement. It is of great clinical significance to predict the therapeutic effect of TGT in RA. Therefore,the aim of the current study was to identify potential biomarkers for TGT treatment in RA. Affymetrix EG1.0 arrays were applied to detect gene expression in peripheral blood mononuclear cells obtained from 6 RA patients( 3 responders and 3 non-responders) treated with TGT. By integrating differential expression data analysis and biomolecular network analysis,360 mRNAs( 185 up-regulated and 175 down-regulated) and 24 miRNAs( 7 up-regulated and 17 down-regulated) which were differentially expressed between TGT responder and non-responder groups were identified. A total of 206 candidate target genes for the differentially expressed miRNAs were obtained based on miRanada and Target Scan databases,and then the miRNA target gene coexpression network and miRNA-mediated gene signal transduction network were constructed. Following the network analyses,three candidate miRNAs biomarkers( hsa-miR-4720-5 p,hsa-miR-374 b-5 p,hsa-miR-185-3 p) were identified as candidate biomarkers predicting individual response to TGT. Partialleast-squares( PLS) was applied to construct a model for predicting response to TGT based on the expression levels of the candidate gene biomarkers in RA patients. The five-fold cross-validation showed that the prediction accuracy( ACC) of this PLS-based model efficacy was 100.00%,100.00%,100.00%,66.67% and 66.67% respectively,and all the area under the receiver operating characteristic curve( AUC) were 1.00,indicating the highly predictive efficiency of this PLS-based model. In conclusion,the integrating transcription data mining and biomolecular network investigation show that hsa-mir-4720-5 p,hsa-mir-374 b-5 p and hsa-mir-185-3 p may be candidate biomarkers predicting individual response to TGT. In addition,the PLS model based on the expression levels of these candidate biomarkers may be helpful for the clinical screen of RA patients,which potentially benefit individualized therapy of RA in a daily clinical setting.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Glicosídeos/uso terapêutico , MicroRNAs/genética , Tripterygium/química , Biomarcadores , Mineração de Dados , Humanos , Leucócitos Mononucleares , Comprimidos
18.
Bioorg Chem ; : 103346, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31645277

RESUMO

Many natural or synthetic chalcones have potential anti-tumor activity. Here, we synthesized two series of chalcone analogues containing a thieno[2,3-d]pyrimidin-2-yl group and evaluated for their cytotoxic activity towards cultured human lung cancer A549 and colorectal HCT-116 cells. Among them, compound 8d was the most cytotoxic against HCT-116 cells, with an IC50 value of 2.65 µM. Analyses of the phenotypic changes induced by this compound found a dose-dependent accumulation of HCT-116 cells in sub-G1 phase, indicating that compound 8d might induce apoptosis. Furthermore, we found that 8d triggered mitochondrial membrane potential depolarization, promoted reactive oxygen species formation in HCT-116 cells, and increased the percentage of early and late apoptotic cells. Finally, immunoblotting indicated that 8d increased PARP-1 and caspases 3, 7 and 9 cleavage. These data suggest that compound 8d induces apoptosis via the mitochondrial death pathway.

19.
Nanoscale ; 11(37): 17340-17349, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31517377

RESUMO

The performance of thermoelectric (TE) materials is strongly influenced by multi-scale defects. Some defects can improve the TE performance but some are unfavorable. Therefore, the multi-scale defects need to be integrated rationally to enhance the TE properties. Here, the defects including atomic-scale point defects, high-density grain boundaries and nano-precipitates were integrated into CuFeS2, an n-type and Earth-abundant TE material. Primitively, a Cd dopant with high scattering factor was introduced to form point defects in Cu1-xCdxFeS2 (x = 0-0.1) according to the calculated scattering parameters. Furthermore, the processes of quenching, annealing, high-energy ball milling (QAH) and sintering were carried out to integrate the multi-scale defects into Cu1-xCdxFeS2. The results suggested that point defects and antisite defects were achieved and the unfavorable Cd'Fe defects were suppressed effectively, leading to a higher electrical conductivity. Moreover, the CdS nano-precipitates played a vital role in carrier filtering to increase the Seebeck coefficient. Meanwhile, the high-density grain boundaries suppressed the lattice thermal conductivity. As a result, a peak ZT value of 0.39 at 723 K was obtained in Cu0.92Cd0.08FeS2, which is the highest value reported so far in the CuFeS2 family.

20.
Int J Phytoremediation ; : 1-8, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31523977

RESUMO

This study investigated the influence of chemical remediation agents (Bc, M, HA, and Bc + HA) on the growth of the halophyte Lycium ruthenicum and the mechanism of restoration of soil salinization using joint halophyte and chemical remediation in arid fields. The results showed that aboveground organ biomass of L. ruthenicum increased significantly with the chemical remediation agents analyze but the effects on the root system were different. Among the root traits, dry weight of the taproot of L. ruthenicum increased significantly (p < 0.05) by 60.57% with HA; however, the lateral roots were inhibited. With the addition of biochar, the content of sodium ions in roots increased significantly. Further analysis showed that endogenous manganese (Mn) promoted K+ absorption concentration increase from 22.09 to 38.28 g/kg. Moreover, Joint L. ruthenicum and chemical remediation with Bc, HA, M and Bc + HA reduced Na+ to 5854.76, 9396.19, 6530.95 and 11164.29 g/(kg DW⋅m2·a), respectively. Tests revealed that for L. ruthenicum, the aboveground biomass and root morphological plasticity, as well as the synergistic effect of K+ on Na+ transport capacity influenced by endogenous Mn in leaves, were the primary causes of the efficient improvement of saline-alkali land.

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