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1.
J Hazard Mater ; 428: 128261, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35033912

RESUMO

To understand the adsorption mechanisms of Cd2+ by oxidant-modified biochar (OMB) derived from Platanus orientalis Linn (POL) leaves, batch adsorption experiments and characterization were carried out. The results showed that, KMnO4-modified biochar (MBC) could more effectively remove Cd2+ from aqueous solution than H2O-, H2O2-, and K2Cr2O7-modified biochar (WBC, HBC and PBC, respectively). The highest removal efficiency was 98.57%, which was achieved by the addition of 2 g L-1 MBC at pH 6.0. According to the Langmuir fitting parameters, the maximum adsorption capacity for MBC was 52.5 mg g-1 at 30 â„ƒ, which was twice as high as that for original biochar. MBC had the largest specific surface area with many particles distributed on the surface before and after adsorption, which were confirmed to be MnOx by XPS analysis. The complexation with MnOx was the main mechanism. Besides, O-containing groups complexation, precipitation, cation-π intraction, and ion exchange also participated in the adsorption. However, WBC, HBC and PBC did not achieve ideal removal effects, and their stability was inferior. This could be attributed to the weakening of ion exchange and precipitation. This study not only demonstrates the potential of MBC, but also provides insight into strategies for the utilization of waste resources.

2.
J Hazard Mater ; 428: 128254, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35051772

RESUMO

In this study, three-dimensional reduced graphene oxide aerogel (rGOA)-supported nanozero-valent iron (rGOA-nZVI) was successfully synthesized via tailored design and applied to activate persulfate (PS) to degrade three organophosphorus pesticides (OPPs; phorate, terbufos and parathion) in water and a historically contaminated soil. The results showed that loading nZVI nanoparticles on rGOA could prevent the aggregation of nZVI. rGOA-nZVI presented a better catalytic performance for PS activation to degrade the three OPPs than bare nZVI and rGOA, with degradation efficiencies of greater than 99.5% within 5 min. pH had negligible effects on the PS activated by rGOA-nZVI (rGOA-nZVI/PS). EPR measurements and radical quenching experiments showed that ·SO4- and ·OH were the main radicals responsible for OPP removal in the rGOA-nZVI/PS system. Furthermore, nine intermediates were identified, and the oxidation and scission of C-S-C, P-S/O and PS were the dominant degradation pathways of the three OPPs in aqueous solutions treated with rGOA-nZVI/PS. Additionally, rGOA-nZVI/PS achieved degradation efficiencies of 95.1% for phorate, 79.9% for terbufos and 89.1% for parathion in the contaminated soil, and the detected intermediates could be further degraded except triethylphosphate. Overall, this study provides practical knowledge for OPP removal by rGOA-nZVI/PS in wastewater and actual contaminated soil.

3.
Environ Pollut ; 296: 118723, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34952181

RESUMO

The present study investigated that the potential of soil or foliar applied 15 mg/L zinc oxide quantum dots (ZnO QD, 11.7 nm) to enhance pumpkin (Cucurbita moschata Duch.) growth and biomass in comparison with the equivalent concentrations of other sizes of ZnO particles, ZnO nanoparticles (ZnO NPs, 43.3 nm) and ZnO bulk particles (ZnO BPs, 496.7 nm). In addition, ZnSO4 was used to set a Zn2+ ionic control. For foliar exposure, ZnO QD increased dry mass by 56% relative to the controls and values were 17.3% greater than that of the ZnO NPs particles. The cumulative water loss in the ZnO QD treatment was 10% greater than with ZnO NPs, suggesting that QD could better enhance pumpkin growth. For the root exposure, biomass and accumulative water loss equivalent across all Zn treatments. No adverse effects in terms of pigment (chlorophyll and anthocyanin) contents were evident across all Zn types regardless exposure routes. Foliar exposure to ZnO QD caused 40% increases in shoot Zn content as compared to the control; the highest Zn content was evident in the Zn2+ ionic treatment, although this did not lead to growth enhancement. In addition, the shoot and root content of other macro- and micro-nutrients were largely equivalent across all the treatments. The contents of other nutritional compounds, including amino acids, total protein and sugar, were also significantly increased by foliar exposure of ZnO QD. The total protein in the ZnO QD was 53% higher than the ZnO particle treatments in the root exposure group. Taken together, our findings suggest that ZnO QDs have significant potential as a novel and sustainable nano-enabled agrichemical and strategies should be developed to optimize benefit conferred to amended crops.


Assuntos
Cucurbita , Nanopartículas , Pontos Quânticos , Óxido de Zinco , Zinco , Óxido de Zinco/toxicidade
4.
J Hazard Mater ; 421: 126750, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34339988

RESUMO

The biological mechanisms underlying the associations between atmospheric ozone exposure and adverse cardiometabolic outcomes are yet to be identified. Imbalanced autonomic nervous system (ANS) as well as activations of the sympatho-adrenomedullary (SAM) and hypothalamic-pituitary-adrenal (HPA) axes are among possible early biological responses triggered by ozone, and may eventually lead to cardiometabolic abnormalities. To determine whether acute ozone exposure causes ANS imbalance and increases the secretion of neuroendocrine stress hormones, we conducted a randomized, double-blind, crossover trial, under controlled 2-hour exposure to either ozone (200 ppb) or clean air with intermittent exercise among 22 healthy young adults. Here we found that, compared to clean air exposure, acute ozone exposure significantly decreased the high-frequency band of heart rate variability, even after adjusting for heart rate and pre-exposure to ambient air pollutants and meteorological factors. Ozone exposure also significantly increased the serum levels of stress hormones, including corticotrophin-releasing factor, adrenocorticotropic hormone, adrenaline, and noradrenaline. Metabolomics analysis showed that acute ozone exposure led to alterations in stress hormones, systemic inflammation, oxidative stress, and energy metabolism. Our results suggest that acute ozone exposure may trigger ANS imbalance and activate the HPA and SAM axes, offering potential biological explanations for the adverse cardiometabolic effects following acute ozone exposure.


Assuntos
Poluentes Atmosféricos , Ozônio , Estudos Cross-Over , Frequência Cardíaca , Hormônios , Humanos , Ozônio/toxicidade , Adulto Jovem
5.
J Hazard Mater ; 426: 128083, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34923382

RESUMO

A novel eco-friendly material (CS-U@PS) for persulfate slow-release to effectively degrade organic pollutants (methyl orange and pyrene) was synthesized using chitosan and urea as the encapsulated framework materials via an emulsion cross-linking method for the first time. The obtained CS-U@PS exhibits spherical shapes with a uniform size of approximately 2-3 µm according to the particle-size distribution and SEM image results. The slow-release mechanism was proposed through a kinetics model study and the Ritger-Peppas model fit well (r2 = 0.9699) to indicate that the slow-release process is non-Fickian diffusion. The influences of urea and PS dosages and oxidative conditions on methyl orange degradation were studied, and all the results suggested that urea played an important role in PS slow-release and can also catalyze the activation of PS by iron to further produce radicals and improve the removal efficiency of pollutants. A pyrene removal rate of 90.53% was achieved in aqueous solutions and an above 80% removal rate was obtained in weakly acidic or neutral soil environments by CS-U@PS activated by Fe2+ with citric acid as the chelating agent. Therefore, the fabricated slow-release oxidation materials exhibit application potential for the remediation of organic polluted groundwater and soil.

6.
J Hazard Mater ; 424(Pt A): 127225, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34600381

RESUMO

Biochar has been widely used in advanced oxidation processes (AOPs) for the decomposition of organic contaminants. However, the role of intrinsic metals in hyperaccumulator biomass in the physico-chemical properties and performance of peroxodisulfate (PDS) activation by biochar is still unclear. This work employed hyperaccumulator biomass containing Fe, Mn and Zn, respectively. Result showed that as the pyrolysis temperature of the biochar increased, Fe was gradually reduced to iron oxide and Fe0, and Zn was reduced and volatilized; however, Mn remained in biochar in the form of MnS and CaMnO3 with high valence states. These thermochemical behaviors of intrinsic metals also facilitated graphitized structure growth and pore development (for Zn) and persistent free radicals (PFRs) generation (for Mn and Zn) in biochar, and these processes were crucial for imidacloprid degradation in biochar/PDS systems. Moreover, Fe/Zn@PB9/PDS showed better imidacloprid degradation performance, while Mn species in Mn@PB were catalytically inert. In addition, the radical pathway depending on·SO4- and·OH was the dominant pathway for imidacloprid degradation in the Fe@PB9/PDS systems, while the·O2--mediated 1O2 pathway and 1O2-based nonradical pathway contributed more in the Zn@PB9/PDS systems. These results reveal the role of intrinsic metals in biochar-based catalysts and provide a reference for the preparation of green and efficient hyperaccumulator-derived biochar catalysts for AOPs.


Assuntos
Carvão Vegetal , Metais , Pirólise , Zinco
7.
Chemosphere ; : 133436, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34968513

RESUMO

Advanced reduction by strong reducing hydrated electrons is a promising approach to degrade per- and polyfluoroalkyl substances (PFAS). This research aimed to investigate the effectiveness of UV/Iodide system for 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA, F-53B) degradation in aqueous solutions. Results from this work demonstrated that UV irradiation with an addition of 0.3 mM KI resulted in 55.99% degradation of F-53B within 15 min and almost 100% within 2 h. The defluorination efficiency of F-53B in the UV/Iodide system was 2.6 times higher than that in the sole UV system after 2 h of irradiation. The degradation efficiency of F-53B was not significantly affected by air purging. The defluorination efficiency with air bubbling, however, was 14.57% lower than that with nitrogen purging. The photodegradation of F-53B in the UV/Iodide system could be well described by a pseudo-first-order kinetic model. Degradation rate constant of F-53B correlated positively with the initial concentration. At 20 µg/L, the pseudo-first-order rate constant was 5.641 × 10-2 min-1 and the half-life was 12.29 min. Higher initial concentration also required less energy input to achieve the same degradation efficiency. The detection and identification of degradation intermediates implied that destruction of F-53B started from dechlorination and followed by continuously "flaking off" CF2 units.

8.
PM R ; 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34553496

RESUMO

BACKGROUND: The iliocapsularis muscle is a structure of the anterior hip, which may play a key role in stabilizing the hip joint, but to our knowledge no studies exist describing ultrasound (US) and shear-wave characteristics of this muscle. OBJECTIVES: To investigate the anatomic dimensions and elasticity of the iliocapsularis muscle in patients with pincer-type femoroacetabular impingement (FAI) and normal hips using gray-scale US and shear-wave elastography (SWE). DESIGN: Case-control study. SETTING: Sports medicine and ultrasound department within a tertiary hospital. PARTICIPANTS: Thirty-three patients (33 hips) with pincer-type FAI and 37 healthy volunteers (37 hips). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: US parameters (anteroposterior diameter, transverse diameter and circumference) of the iliocapsularis muscle in patients with pincer-type FAI and volunteers. Shear-wave velocity and Young's modulus of the iliocapsularis muscle in patients with pincer-type FAI and volunteers in both neutral and external rotation positions. RESULTS: Significant differences were not observed in the anatomic dimensions of the iliocapsularis muscle between patients with pincer-type FAI and volunteers. The iliocapsularis muscle in patients with pincer-type FAI had significantly lower shear-wave velocity and Young's modulus than the volunteers (p < .05). The cutoff value of the maximum velocity in the external rotation position was 3.35 m/s, which separated pincer-type FAI patients from volunteers and revealed the highest accuracy with sensitivity, specificity, and accuracy of 78.8%, 48.6%, and 64.3%, respectively. CONCLUSION: The anatomic dimensions of the iliocapsularis muscle in pincer-type FAI patients and volunteers were similar; however, iliocapsularis stiffness in patients with pincer-type FAI was significantly lower than that of the volunteers. SWE can demonstrate altered muscle stiffness of the iliocapsularis muscle in pincer-type FAI patients, which might be used to help make clinical decisions.

9.
Chem Asian J ; 16(21): 3419-3426, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34476907

RESUMO

The detection of changes in the reactive oxygen species (ROS)/reactive sulfur species (RSS) couple is important for studying the cellular redox state. Herein, we developed a 1,8-naphthalimide-based fluorescence probe (NI) for the reversible detection of bisulfite (HSO3 - ) and hydrogen peroxide (H2 O2 ) in vitro and in vivo. NI has been designed with a reactive ethylene unit which specifically reacts with HSO3 - by a Michael addition reaction mechanism, resulting in the quenching of yellow fluorescence at 580 nm and the appearing of green fluorescence at 510 nm upon excitation at 500 nm and 430 nm, respectively. The addition product (NI-HSO3 ) could be specifically oxidized to form the original C=C bond of NI, recovering the fluorescence emission and color. The detection limits of NI for HSO3 - and NI-HSO3 for H2 O2 were calculated to be 2.05 µM and 4.23 µM, respectively. The reversible fluorescence response of NI towards HSO3 - /H2 O2 couple can be repeated for at least five times. NI is reliable at a broad pH range (pH 3.0-11.5) and features outstanding selectivity, which enabled its practical applications in biological and food samples. Monitoring the reversible and dynamic inter-conversion between HSO3 - and H2 O2 in vitro and in vivo has been verified by fluorescence imaging in live HeLa cells, adult zebrafish and nude mice. Moreover, NI has been successfully applied to detect of HSO3 - levels in food samples.

10.
World J Surg Oncol ; 19(1): 230, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362391

RESUMO

BACKGROUND: Accumulating evidence indicates that miRNAs are involved in multiple cellular functions and participate in various cancer development and progression, including breast cancer. METHODS: We aimed to investigate the role of miR-381-3p in breast cancer. The expression level of miR-381-3p and EMT transcription factors was examined by quantitative real-time PCR (qRT-PCR). The effects of miR-381-3p on breast cancer proliferation and invasion were determined by Cell Counting Kit-8 (CCK-8), colony formation, and transwell assays. The regulation of miR-381-3p on its targets was determined by dual-luciferase analysis, qRT-PCR, and western blot. RESULTS: We found that the expression of miR-381-3p was significantly decreased in breast cancer tissues and cell lines. Overexpression of miR-381-3p inhibited breast cancer proliferation and invasion, whereas knockdown of miR-381-3p promoted cell proliferation and invasion in MDA-MB-231 and SKBR3 cells. Mechanistically, overexpression of miR-381-3p inhibited breast cancer epithelial-mesenchymal transition (EMT). Both Sox4 and Twist1 were confirmed as targets of miR-381-3p. Moreover, transforming growth factor-ß (TGF-ß) could reverse the effects of miR-381-3p on breast cancer progression. CONCLUSIONS: Our observation suggests that miR-381-3p inhibits breast cancer progression and EMT by regulating the TGF-ß signaling via targeting Sox4 and Twist1.


Assuntos
Neoplasias da Mama , Transição Epitelial-Mesenquimal , MicroRNAs , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Proteínas Nucleares , Prognóstico , Fatores de Transcrição SOXC , Proteína 1 Relacionada a Twist
11.
Oncol Rep ; 46(1)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33982790

RESUMO

MicroRNAs are important for the regulation of multiple cellular functions and are involved in the initiation and progression of various types of cancer, including breast cancer. Although microRNA (miR)­454­3p is reported to function as an oncogene in several types of human cancer, the role of miR­454­5p in breast cancer remains unknown. The present study demonstrated that miR­454­5p was upregulated in breast cancer and was associated with a poor prognosis in patients with breast cancer. Overexpression of miR­454­5p promoted breast cancer cell viability, migration and invasion in vitro, whereas silencing of miR­454­5p inhibited breast cancer proliferation, migration and invasion in vitro and suppressed tumor growth in vivo. Mechanistically, forkhead box J2 (FoxJ2) was shown to be a target of miR­454­5p and transactivated E­cadherin expression. Moreover, silencing of miR­454­5p reversed the epithelial­mesenchymal transition phenotype through upregulation of the FoxJ2/E­cadherin axis. Collectively, the present findings suggested that miR­454­5p may serve as a novel therapeutic target and prognostic predictor for patients with breast cancer.


Assuntos
Antígenos CD/genética , Neoplasias da Mama/patologia , Caderinas/genética , Fatores de Transcrição Forkhead/genética , MicroRNAs/genética , Regulação para Cima , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Progressão da Doença , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Camundongos , Transplante de Neoplasias , Prognóstico
12.
Chemosphere ; 281: 130760, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33992847

RESUMO

Sulfidation treatment is an effective method of improving the catalytic performance of zero-valent iron (ZVI). Here, we prepared sulfidated, micro-sized ZVI (S-mZVI) using ball milling technology to activate persulfate (PS) with the goal of oxidizing organophosphorus pesticides (OPPs) in aqueous solution and aged OPP-contaminated soil columns. Energy dispersive spectroscopy (EDS), X-ray powder diffraction (XRD) and X-ray photoelectron spectrometry (XPS) analyses uncovered the formation of Fe2O3, FeOOH, FeS and FeS2 in the S-mZVI prepared by ball milling with different proportions of elemental S powder to make micro-sized ZVI particles. The presence of sulfur can regulate the morphology of S-mZVI with a dispersed and spherical shape, and it can improve the activation performance of PS. In aqueous solution, 11.2 mg of S-mZVI activated 2.5 mM PS (S-mZVI-PS) with an S/Fe molar ratio of 0.100, and it was the best at activating PS, leading to oxidation-rate constants of 0.030 s-1 for 10 mg/L phorate and 0.026 s-1 for 10 mg/L terbufos, which were much greater than those of the other S-mZVI and mZVI. The results of the soil column experiment showed that the PS, which had a low consumption for the total dosage, achieved higher degradation percentages among the three OPPs in the S-mZVI-PS treatment than those in the mZVI-PS treatment over 120 h, with the best performance achieved by oxidizing 69.7% phorate, 48.0% terbufos and 60.6% aminoparathion. The effluent concentrations of the three OPPs in the S-mZVI-PS treatment were significantly lower than those in the mZVI-PS treatment, while dissolved total iron and Fe(II) displayed the opposite results. These results indicate that S-mZVI prepared by ball milling can effectively activate PS and be applied to remediate OPP-contaminated soil.


Assuntos
Praguicidas , Poluentes Químicos da Água , Ferro , Oxirredução , Solo
13.
Chemosphere ; 281: 130780, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33992850

RESUMO

Heavy metals and organic pollutants could pose long-term threats to the ecosystem and human health, so it is urgent for us to find a friendly and efficient material to remove pollutants in environment. Since tourmaline is widely distributed in natural environment and has many excellent physical and chemical properties including radiating far infrared energy, permanently releasing negative ions, producing an electrostatic field, releasing rare microelements, and stimulating the growth and metabolism of microorganisms and plants, tourmaline had been conducted to alleviate environmental pollution. This review summarizes the application of tourmaline in aqueous solutions and soil polluted by heavy metals and organic pollutants, the factors that affect the removal of pollutants by tourmaline and the removal mechanisms. In addition, to ensure the safe use of tourmaline, this review also elaborates the environment risks of tourmaline through its toxicity indexes to soil and plant.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Ecossistema , Poluição Ambiental , Humanos , Metais Pesados/análise , Silicatos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
14.
Materials (Basel) ; 14(8)2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33920304

RESUMO

W-20 wt.% Cu pseudo-alloys were produced via powder injection molding (PIM) with powders prepared thermochemically. Bonding treatment and ball milling (BTBM) were used, and the effects of BTBM on the characteristics of the powders, rheological properties of the feedstock, shrinkage and properties of the sintered samples were studied. The morphology of the powder changed from extremely agglomerated small particles to pebble-shaped smooth large particles which were composed of several small particles combined tightly. The tap density increased from 3.25 g/cm3 to 7.22 g/cm3, and the specific surface area decreased from 0.86 m2/g to 0.45 m2/g. The critical powder loading of the feedstock increased from 45 vol.% to 56 vol.% due to the change in powder characteristics, thereby improving densification and dimension precision. For the PIM samples sintered at 1290 °C for 120 min in a hydrogen gas, the oversizing factor decreased from 1.297 to 1.216, and the dimension fluctuation ratio decreased from ±0.61% to ±0.33%. At the same time, the relative density increased from 97.8% to 98.6%, the thermal conductivity increased from 218 W/(m·K) to 233 W/(m·K), and the average coefficients of thermal expansion were roughly similar, within the range of 8.43-8.52 × 10-6/K.

15.
Sci Total Environ ; 772: 145554, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33770853

RESUMO

To understand the effect mechanisms of iron plaque and fatty acids on the migration of PBDEs from soil to rice (Oryza sativa), pot experiments were conducted in the soil spiked with decabromodiphenyl ether (BDE-209) under the conditions of tourmaline and nano-goethite Fenton-like treatments. The results showed that iron mineral Fenton-like oxidation could effectively remove BDE-209 from rhizosphere soil, the highest removal rate obtained 89.29% with the addition of 0.4 mmol/L H2O2 and 8 g nano-goethite (G + 3H group). Iron mineral Fenton-like oxidation could produce iron plaque (IP) on rice roots and accumulate a part of contaminants on the surface of IP, further weakening BDE-209 uptake in the plants. Additionally, the occurrence of fatty acid variation induced by BDE-209 stress, iron mineral Fenton-like oxidation at high concentrations of H2O2 with 0.4 mmol/L affected the distribution of fatty acids in plant tissues, especially for C18:0 fatty acid. While the IP on rice roots prevented the BDE-209 into plant, it was also closely related to the distribution of fatty acids in rice, altering BDE-209 accumulation in the rice. To safely use the iron mineral Fenton-like oxidation in the agricultural soil remediation, the safety of plant cells treated by mineral Fenton-like oxidation was evaluated using the transmission electron microscopy (TEM) and enzyme activity determination, which indicated that iron mineral Fenton-like oxidation would destroy the inner structures of plant cells, especially for G + 3H group.


Assuntos
Oryza , Poluentes do Solo , Ácidos Graxos , Éteres Difenil Halogenados/análise , Peróxido de Hidrogênio , Ferro/análise , Minerais , Raízes de Plantas/química , Solo , Poluentes do Solo/análise
16.
Chemosphere ; 277: 130259, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33773320

RESUMO

In the present study, two magnetic multi-walled carbon nanotubes (MMWCNTs) with different ratios of Fe2+/Fe3+ were prepared, and the effects of different fractions of dissolved humic acid (DHA) on the adsorption of phenanthrene by multi-walled carbon nanotubes (MWCNTs) and MMWCNTs from the aqueous solution were investigated. The adsorption kinetics of DHA1 and DHA4 were best fitted with pseudo-second order model. The adsorption of DHAs on MMWCNTs was weaker than that on MWCNTs, and DHA1 was easier to adsorb to MWCNTs and MMWCNTs than DHA4. The phenanthrene adsorption capacities by 1:2:1MMWCNTs and 4:2:1MMWCNTs with higher polar groups and magnetic gradient were less than that of MWCNTs. The pH value had no obvious effect on the adsorption of phenanthrene to MWCNTs loaded with different iron. Additionally, the DHAs could form soluble complexes of DHAs-Fe (II) in solution to reduce the phenanthrene adsorption on MMWCNTs, DHA1 inhibit more obviously phenanthrene adsorbed onto MWCNTs and MMWCNTs than DHA4. As for MMWCNTs, the main mechanisms of phenanthrene adsorbed onto it included new adsorption sites formed by π-π interaction and magnetic gradient. In this study, MMWCNTs after adsorbed DHAs had a weaker inhibitory effect on phenanthrene adsorption than MWCNTs, implying that when phenanthrene is adsorbed by DHAs-coated MMWCNTs, the bioavailability and mobility of phenanthrene will be reduced, and it is easy to be removed by the magnet for further processing.


Assuntos
Nanotubos de Carbono , Fenantrenos , Adsorção , Substâncias Húmicas/análise , Fenômenos Magnéticos , Solo
17.
Ecotoxicol Environ Saf ; 208: 111726, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396057

RESUMO

BACKGROUND: It remains unclear which size of particles has the strongest effects on heart rate variability (HRV). OBJECTIVE: To explore the association between HRV parameters and daily variations of size-fractionated particle number concentrations (PNCs). METHODS: We conducted a longitudinal repeated-measure study among 78 participants with a 24-h continuous ambulatory Holter electrocardiographic recorder in Shanghai, China, from January 2015 to June 2019. Linear mixed-effects models were employed to evaluate the changes of HRV parameters associated with PNCs of 7 size ranges from 0.01 to 10 µm after controlling for environmental and individual confounders. RESULTS: On the concurrent day, decreased HRV parameters were associated with increased PNCs of 0.01-0.3 µm, and smaller particles showed greater effects. For an interquartile range increase in ultrafine particles (UFP, those < 0.1 µm, 2453 particles/cm3), the declines in very-low-frequency power, low-frequency power, high-frequency power, standard deviation of normal R-R intervals, root mean square of the successive differences between R-R intervals and percentage of adjacent normal R-R intervals with a difference ≥ 50 ms were 5.06% [95% confidence interval (CI): 2.09%, 7.94%], 7.65% (95%CI: 2.73%, 12.32%), 9.49% (95%CI: 4.64%, 14.09%), 5.10% (95%CI: 2.21%, 7.91%), 8.09% (95%CI: 4.39%, 11.65%) and 24.98% (95%CI: 14.70%, 34.02%), respectively. These results were robust to the adjustment of criteria air pollutants, temperature at different lags, and the status of heart medication. CONCLUSIONS: Particles less than 0.3 µm (especially UFP) may dominate the acute effects of particulate air pollution on cardiac autonomic dysfunction.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Material Particulado/análise , Poluição do Ar/análise , China , Feminino , Cardiopatias , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Temperatura
18.
ESC Heart Fail ; 8(1): 447-460, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33236535

RESUMO

AIMS: Previous reports indicated that the Slit2-Robo signalling pathway is involved in embryonic heart development and fibrosis in other solid organs, but its function in adult cardiac fibrosis has not been investigated. Here, we investigate the role of the Slit2-Robo1 signalling pathway in cardiac fibrosis. METHODS AND RESULTS: The right atrial tissue samples were obtained from patients with valvular heart disease complicated by atrial fibrillation during heart valve surgery and from healthy heart donors. The fibrotic animal model is created by performing transverse aortic constriction (TAC) surgery. The Robo1, Slit2, TGF-ß1, and collagen I expression levels in human and animal samples were evaluated by immunohistochemistry and western blot analysis. Echocardiography measured the changes in heart size and cardiac functions of animals. Angiotensin II (Ang II), Slit2-siRNA, TGF-ß1-siRNA, recombinant Slit2, and recombinant TGF-ß1 were transfected to cardiac fibroblasts (CFs) respectively to observe their effects on collagen I expression level. The right atrial appendage of patients with valvular heart disease complicated by atrial fibrillation found significantly up-regulated Slit2, Robo1, TGF-ß1, and collagen I expression levels. TAC surgery leads to heart enlargement, cardiac fibrosis, and up-regulation of Slit2, Robo1, TGF-ß1, and collagen I expression levels in animal model. Robo1 antagonist R5 and TGF-ß1 antagonist SB431542 suppressed cardiac fibrosis in TAC mice. Treatment with 100 nM Ang II in CFs caused significantly increased Slit2, Robo1, Smad2/3, TGF-ß1, collagen I, PI3K, and Akt expression levels. Transfecting Slit2-siRNA and TGF-ß1-siRNA, respectively, into rat CFs significantly down-regulated Smad2/3 and collagen I expression, inhibiting the effects of Ang II. Recombinant Slit2 activated the TGF-ß1/Smad signalling pathway in CFs and up-regulated Periostin, Robo1, and collagen I expression. CONCLUSIONS: The Slit2-Robo1 signalling pathway interfered with the TGF-ß1/Smad pathway and promoted cardiac fibrosis. Blockade of Slit2-Robo1 might be a new treatment for cardiac fibrosis.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/genética , Miocárdio/patologia , Proteínas do Tecido Nervoso/genética , Receptores Imunológicos , Transdução de Sinais , Fator de Crescimento Transformador beta1 , Animais , Fibrose , Humanos , Camundongos , Ratos , Receptores Imunológicos/genética
19.
Chemosphere ; 267: 129213, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33338715

RESUMO

In this study, waste pomelo peels (PP) mixed with iron salts was treated successively with hydrothermal and pyrolyzing carbonization processes to obtain Fe(0) containing biochar composites (Fe@PP-Hy-Py) and the catalytic degradation of p-nitrophenol (PNP) using these Fe@PP-Hy-Py composites was studied. The results showed that the hydrothermal pre-treatment of the mixture of iron salts and pomelo peels was favorable for the incorporation of iron precursor within biomass network, which enabled copolymerization during the following pyrolysis. Through the pyrolysis process, the iron precursor was reduced in situ to amorphous Fe(0) dopped into the carbonaceous matrix, which conversely decreased the defect and disorder degree of pseudo-graphitic carbons and catalyzed the formation of environmental persistent free radicals (EPFRs). Degradation tests showed that the composites obtained at 600 °C with the theoretical Fe mass loading of 10% exhibited the greatest PNP degradation efficiency. Over 90% of 10 mg/L PNP was removed in 2 min under both N2 and air conditions with 1.0 g/L of catalyst level. The degradation kinetics of PNP were all well fitted by the pseudo-first-order kinetics model with kobs of Fe@PP-Hy-Py600 being 0.953 min-1. HPLC-QTOF/MS analysis demonstrated that both oxidation and reduction of PNP occurred as indicated by the detection of 4-aminophenol and ring opening compounds. The Fe(0) on the Fe@PP-Hy-Py was responsible for the reduction of PNP, while oxidation was induced by EPFRs. This study highlights the feasibility of synthesizing active heterogeneous Fe(0)-biochar composites by hydrothermal-pyrolysis route and the associated mechanisms of pollutant degradation.


Assuntos
Poluentes Químicos da Água , Carvão Vegetal , Nitrofenóis , Poluentes Químicos da Água/análise
20.
Environ Res ; 194: 110655, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33358871

RESUMO

BACKGROUND: The impacts of temperature variability on cardiac autonomic function remain unclear. OBJECTIVE: To explore the short-term associations between daily temperature variability and parameters of heart rate variability (HRV). METHODS: This is a repeated-measure study among 78 eligible participants in Shanghai, China. We defined temperature variability as diurnal temperature range (DTR), the standard-deviation of temperature (SDT) and temperature variability (TV). We evaluated 3 frequency-domain HRV parameters (VLF, LF and HF) and 4 time-domain parameters (SDNN, SDANN, rMSSD and pNN50). We used linear mixed-effect models to analyze the data after controlling for environmental and individual confounders. RESULTS: Temperature variability was significantly associated with decreased HRV, especially on the concurrent day. The exposure-response relationships were almost inversely linear for most parameters. Every one interquartile range (IQR) increase of DTR was associated with a decrease of 3.92% for VLF, 6.99% for LF, 5.88% for HF, 3.94% for rMSSD and 1.30% for pNN50. Each IQR increase of SDT was associated with a decline of 6.48% for LF, 5.91% for HF, 4.26% for rMSSD and 1.87% for pNN50. Every IQR increase of SDT was associated with a decrease of 4.39% for VLF, 7.67% for LF, 6.52% for HF, 3.22% for SDNN, 2.98% for SDANN, 4.05% for rMSSD, and 1.41% for pNN50. The decrements in HRV associated with temperature variability were more prominent in females. CONCLUSION: Temperature variability on the concurrent day could significantly decrease cardiac autonomic function, especially in females.


Assuntos
Sistema Nervoso Autônomo , Coração , China , Feminino , Frequência Cardíaca , Humanos , Temperatura
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