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1.
Alzheimers Res Ther ; 16(1): 22, 2024 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-38281031

RESUMO

BACKGROUND: Alzheimer's disease (AD) is one of the most burdening diseases of the century with no disease-modifying treatment at this time. Nonhuman primates (NHPs) share genetic, anatomical, and physiological similarities with humans, making them ideal model animals for investigating the pathogenesis of AD and potential therapies. However, the use of NHPs in AD research has been hindered by the paucity of AD monkey models due to their long generation time, ethical considerations, and technical challenges in genetically modifying monkeys. METHODS: Here, we developed an AD-like NHP model by overexpressing human tau in the bilateral hippocampi of adult rhesus macaque monkeys. We evaluated the pathological features of these monkeys with immunostaining, Nissl staining, cerebrospinal fluid (CSF) analysis, magnetic resonance imaging (MRI), positron emission tomography (PET), and behavioural tests. RESULTS: We demonstrated that after hippocampal overexpression of tau protein, these monkeys displayed multiple pathological features of AD, including 3-repeat (3R)/4-repeat (4R) tau accumulation, tau hyperphosphorylation, tau propagation, neuronal loss, hippocampal atrophy, neuroinflammation, Aß clearance deficits, blood vessel damage, and cognitive decline. More interestingly, the accumulation of both 3R and 4R tau is specific to NHPs but not found in adult rodents. CONCLUSIONS: This work establishes a tau-induced AD-like NHP model with many key pathological and behavioural features of AD. In addition, our model may potentially become one of the AD NHP models adopted by researchers worldwide since it can be generated within 2 ~ 3 months through a single injection of AAVs into the monkey brains. Hence, our model NHPs may facilitate mechanistic studies and therapeutic treatments for AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Animais , Doença de Alzheimer/genética , Proteínas tau/metabolismo , Macaca mulatta/metabolismo , Disfunção Cognitiva/patologia , Hipocampo/patologia , Peptídeos beta-Amiloides/metabolismo
2.
Adv Mater ; 36(6): e2307855, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37897435

RESUMO

Perovskite solar cells (PSCs) are promising candidates for next-generation photovoltaics owing to their unparalleled power conversion efficiencies (PCEs). Currently, approaches to further improve device efficiencies tend to focus on the passivation of interfacial defects. Although various strategies have been developed to mitigate these defects, many involve complex and time-consuming post-treatment processes, thereby hindering their widespread adoption in commercial applications. In this work, a concise but efficient in situ dual-interface passivation strategy is developed wherein 1-butyl-3-methylimidazolium methanesulfonate (MS) is employed as a precursor additive. During perovskite crystallization, MS can either be enriched downward through precipitation with SnO2 , or can be aggregated upward through lattice extrusion. These self-assembled MS species play a significant role in passivating the defect interfaces, thereby reducing nonradiative recombination losses, and promoting more efficient charge extraction. As a result, a PCE >25% (certified PCE of 24.84%) is achieved with substantially improved long-term storage and photothermal stabilities. This strategy provides valuable insights into interfacial passivation and holds promise for the industrialization of PSCs.

3.
Talanta ; 269: 125380, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37995639

RESUMO

In this study, we designed and prepared a trastuzumab-coupled drug delivery system with pH response characteristics using mesoporous zeolitic imidazolate framework-8 (ZIF-8) as the carrier, Trastuzumab@ZIF-8@DOX. As results, the targeted drug delivery system (TDDS) ultimately showed high drug loading and good biocompatibility. The cumulative curve of drug release indicated that the early leakage levels were low under neutral pH conditions. However, under acidic pH conditions, there was an effective enhancement in drug release, indicating the presence of an explicit pH-triggered drug release mechanism. The results indicate that the prepared nanoparticles have the potential to serve as drug delivery systems, as they can release the loaded drug in a controlled manner. The results of cellular uptake tests showed that the uptake of the nanoparticles was greatly enhanced by the internalization mediated by the HER2 antibody. This finding indicates that the prepared nanoparticles can selectively target cancer cells that overexpress HER2. When the doxorubicin dose was 5 µg/ml, the survival rate of SK-BR-3 cells (cancer cells) was 47.75 %, and the survival rate of HaCaT cells (healthy cells) was 75.25 % when co-cultured with both cells. The therapeutic efficacy of Trastuzumab@ZIF-8@DOX was assessed on BALB/c nude mice to validate its potential as an effective drug delivery system for tumor inhibition in vivo. In conclusion, these findings demonstrate the specificity-targeted and pH-responsive nature of this smart drug delivery system, highlighting its promising prospects for efficient and controllable cancer treatment applications.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Animais , Camundongos , Camundongos Nus , Sistemas de Liberação de Medicamentos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Trastuzumab/farmacologia , Portadores de Fármacos , Concentração de Íons de Hidrogênio
4.
Chemosphere ; 338: 139388, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37423409

RESUMO

Zero-valent iron (ZVI) and modified ZVI have been investigated extensively for groundwater remediation. However, ZVI based powder was difficult to be applied directly as permeable reactive barrier (PRB) materials due to their low water permeability and usage rate. In this study, sulfide iron-copper bimetal was prepared by ball milling, which is environment-friendly without second contamination. The optimal preparation parameters of sulfide iron-copper bimetal for Cr(VI) removal were determined (Cu/Fe ratio (w/w), 0.018; FeS/Fe ratio (w/w), 0.1213; ball milling speed, 450 rpm; ball milling time, 5 h). A composite permeable material was prepared by sintering a mixture of sulfide iron-copper bimetal, sludge, and kaolin. The parameters for composite permeable material preparation including sludge content and particle size, and sintering time were optimized, which were 60%, 60-75 mesh, and 4 h, respectively. The optimal composite permeable material was characterized by SEM-EDS, XRD, and FTIR. The results demonstrated preparation parameters can affect the hydraulic conductivity and hardness of composite permeable material. High sludge content, small particles size, and moderate sintering time resulted in high permeability of composite permeable material and were beneficial for Cr(VI) removal. The dominant Cr(VI) removal mechanism was reduction, and the reaction followed pseudo-first order kinetics. Conversely, low sludge content and large particle size, and long sintering time lead to low permeability of composite permeable material. Chromate removal was mainly by chemisorption following pseudo-second order kinetics. The hydraulic conductivity and hardness of the optimal composite permeable material achieved 1.732 cm/s and 50, respectively. The results of column experiments indicated that its Cr(VI) removal capacity was 0.54 mg/g, 0.39 mg/g and 0.29 mg/g at pH 5, 7 and 9, respectively. The ratio of Cr(VI) to Cr(III) on composite permeable material surface was similar under acidic and alkaline conditions. This study will provide an effective reactive material of PRB for field application.


Assuntos
Ferro , Poluentes Químicos da Água , Ferro/química , Cobre , Cinética , Esgotos , Poluentes Químicos da Água/análise , Cromo/química , Sulfetos
5.
Sci Total Environ ; 892: 164743, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37302601

RESUMO

In this study, Cr(VI)-contaminated soil mixed with COPR by using ferrous sulfate (FeSO4), enzyme residue (ER), and their combination under aerobic or anaerobic condition were investigated. The concentration of Cr(VI) decreased from 1498.05 to 104.63 mg kg-1 after the simultaneous addition of FeSO4 (30 %, w/w as FeSO4·7H2O) and ER (30 %, w/w) at 45 d under the anaerobic condition with a reduction efficiency of 93.02 %, which is higher than that by single FeSO4 (72.39 %) or ER (75.47 %) under the anaerobic condition. XRD, XPS, FTIR, and fluorescence spectroscopy were conducted to characterize soil and ER composition. Metagenomic analysis was performed to reveal the reduction mechanisms of FeSO4 and ER. The anaerobic condition with lower Eh was beneficial for Cr(VI) reduction than aerobic condition, and Eh was the main driver for the evolution of Cr(VI) reduction-related microorganisms. Moreover, the addition of ER enriched the organic matter and microbials in the soil. During the decomposition of organic matter under the anaerobic condition, organic acids were generated, leading to a decrease in pH and promoting the release of Cr(VI) from minerals. They also served as electron donors in Cr(VI) reduction. Additionally, the addition of excess FeSO4 stimulated the growth of iron-reducing bacteria and sulfate-reducing bacteria, facilitating to Cr(VI) reduction. Metagenomic analysis showed that Acinetobacter, related to the nemA and nfsA genes, was the dominant Cr(VI) reduction genus. Thus, the combination of FeSO4 and ER is a promising method for the remediation of Cr(VI)-contaminated soils mixed with COPR.


Assuntos
Compostos Ferrosos , Poluentes do Solo , Compostos Ferrosos/química , Cromo/análise , Resíduos Industriais/análise , Solo , Poluentes do Solo/análise
6.
Adv Mater ; 35(26): e2301127, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37119501

RESUMO

The electrochemical reduction of carbon dioxide into multi-carbon products (C2+ ) using renewably generated electricity provides a promising pathway for energy and environmental sustainability. Various oxide-derived copper (OD-Cu) catalysts have been showcased, but still require high overpotential to drive C2+ production owing to sluggish carbon-carbon bond formation and low CO intermediate (*CO) coverage. Here, the dilemma is circumvented by elaborately devising the OD-Cu morphology. First, computational studies propose a hollow and hierarchical OD-Cu microstructure that can generate a core-shell microenvironment to inhibit CO evolution and accelerate *CO dimerization via intermediate confinement and electric field enhancement, thereby boosting C2+ generation. Experimentally, the designed nanoarchitectures are synthesized through a heteroseed-induced approach followed by electrochemical activation. In situ spectroscopic studies further elaborate correlation between *CO dimerization and designed architectures. Remarkably, the hierarchical OD-Cu manifests morphology-dependent selectivity of CO2 reduction, giving a C2+ Faradaic efficiency of 75.6% at a considerably positive potential of -0.55 V versus reversible hydrogen electrode.

7.
Anal Methods ; 15(10): 1286-1296, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36804584

RESUMO

In most of the near-infrared studies, near-infrared spectra (NIRS) were often mathematically treated. However, these algorithms selected a large number of variables and latent variables, and they caused the over-fitting phenomenon, which became very common. The large number of variables made it impossible to extract the "chemical information" directly from the NIRS. To build robust and interpretable mathematical models, the non-dominated sorting genetic-II-competitive adaptive reweighted sampling (NSGAII-CARS) algorithm was proposed to determine influential functional groups for quantitative analysis. In this research, data on a primary mixture of two amino acids (AAs), namely NH2(CH2)3COOH and HOOC(NH2)CH(CH2)2COOH, was used to illustrate the algorithm. The principle of the algorithm was first to find out the different characteristic spectral regions of two amino acids by extreme points according to Non-dominated Sorting Genetic-II (NSGAII). Second, based on the absolute value of the regression coefficient, we found out [ν(CH2) + 2δ(CH2)] and [2ν(CH2)], where the wavenumber ranged from 6165 to 5683 cm-1, were the influential functional groups for quantitative analysis. Finally, the CARS (competitive adaptive reweighted sampling) algorithm was combined with NSGAII to find the specific fingerprint points for the determination of two AAs. Compared with the previous results, the NSGAII-CARS algorithm not only pointed out the influential quantitative functional groups but also used only 6 points for HOOC(NH2)CH(CH2)2COOH and 18 points for NH2(CH2)3COOH to achieve the full-spectrum quantitative effect. The results proposed a general algorithm for the quantitative analysis of NIRS obtained in the binary or ternary mixed systems. The MATLAB codes of the NSGAII-CARS algorithm are available on the website: https://github.com/Mark1988NK/NSGAII-CARS-Algorithm.git.

8.
Environ Sci Pollut Res Int ; 30(15): 45259-45273, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36705826

RESUMO

Porous sludge biochar (PSDBC) and zero-valent iron (ZVI) supported on porous sludge biochar composite (ZVI@PSDBC) were synthesized using municipal sludge through pyrolysis under N2 atmosphere, which manifested upgraded performance in persulfate (PS) activation for 2,4-dichlorophenol (2,4-DCP) degradation. The 2,4-DCP (50 mg/L) could be almost completely removed within 20 min under relatively low PS dosage (0.5 mmol/L) in both PSDBC/PS and ZVI@PSDBC/PS systems, and the mineralization rate could respectively approach 73.7% and 91.6% in 60 min. Combined with a scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) characterization and electron spin-resonance (ESR) detection, electrochemical analysis, the radical and non-radical pathways in the catalytic systems were discussed. Graphitized structure and superior conductivity made PSDBC and ZVI@PSDBC not only act as electron donors in PS activation to create radicals (mainly SO4·- and ·OH), but also as "mediators" to facilitate the direct electron transfer from 2,4-DCP to the catalysts-PS complexes. The C=O groups of PSDBC and ZVI@PSDBC aided in the production of 1O2. Meanwhile, zero-valent iron nanoparticles promoted the formation of radicals as the reactive sites of PS, resulting in the most effective 2,4-DCP degradation in the ZVI@PSDBC/PS system. The stability and practicability of sludge biochar materials had been demonstrated in reusability and actual wastewater experiments. The findings provided a promising way for the reuse of municipal sludge and effective PS activation in wastewater treatment.


Assuntos
Esgotos , Poluentes Químicos da Água , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Ferro/química , Carvão Vegetal/química , Oxirredução
9.
Artigo em Inglês | MEDLINE | ID: mdl-35955077

RESUMO

The alkali digestion pretreatment method in the United States Environmental Protection Agency (USEPA) Method 3060A could underestimate the content of Cr(VI) in Cr-contaminated soils, especially for soils mixed with chromite ore processing residue (COPR), which leads to a misjudgment of the Cr(VI) level in soils after remediation, causing secondary pollution to the environment. In this study, a new pretreatment method to analyze Cr(VI) concentration in contaminated soils was established. The impacts of soil quality, particle size, alkali digestion time and the rounds of alkali digestion on Cr(VI) detection in contaminated soils was explored and the alkali digestion method was optimized. Compared with USEPA Method 3060A, the alkaline digestion time was prolonged to 6 h and multiple alkali digestion was employed until the amount of Cr(VI) in the last extraction was less than 10% of the total amount of Cr(VI). Because Cr(VI) in COPR is usually embedded in the mineral phase structure, the hydration products were dissolved and Cr(VI) was released gradually during the alkaline digestion process. The amount of Cr(VI) detected showed high correlation coefficients with the percentage of F1 (mild acid-soluble fraction), F2 (reducible fraction) and F4 (residual fraction). The Cr(VI) contents detected by the new alkaline digestion method and USEPA Method 3060A showed significant differences for soil samples mixed with COPR due to their high percentage of residual fraction. This new pretreatment method could quantify more than 90% of Cr(VI) in Cr-contaminated soils, especially those mixed with COPR, which proved to be a promising method for Cr(VI) analysis in soils, before and after remediation.


Assuntos
Resíduos Industriais , Poluentes do Solo , Álcalis/análise , Álcalis/metabolismo , Cromo/análise , Resíduos Industriais/análise , Solo/química , Poluentes do Solo/análise
10.
J Hazard Mater ; 421: 126810, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34365231

RESUMO

The pollution of perfluorooctanoic acid (PFOA) in water bodies has been a serious threat to environment and human health. Ordered mesoporous carbons (OMCs) with different oxygen contents were prepared and first used for adsorbing PFOA from aqueous solutions. The OMC-900 with a lower oxygen content has a higher PFOA adsorption capacity than the oxygen-rich OMC-700. OMCs require a much shorter time to reach the adsorption equilibrium comparing with other adsorbents reported in literature. The mesopores play an important role in this rapid adsorption kinetics. The pseudo-second-order model better fitted the kinetic data. The multilayers adsorption was proposed for the adsorption of PFOA onto OMCs since the Freundlich isotherm model fits the experimental data well. The micelle or hemi-micelle structures may be formed during the adsorption. Various background salts showed a positive effect on PFOA adsorption due to the salting-out and divalent bridge effects. The humic acid can lead to a discernible reduction in PFOA adsorption by competing for adsorption sites on OMCs. The hydrophobic interaction and electrostatic interaction adsorption mechanisms were proposed and verified by the adsorption data. The high adsorption capacity and fast adsorption kinetics of the OMC make it a potential adsorbent for PFOA removal in engineering applications.


Assuntos
Carbono , Fluorocarbonos , Adsorção , Caprilatos , Humanos , Cinética , Oxigênio
11.
Environ Pollut ; 289: 117841, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34325094

RESUMO

It is possible for heavy metals in soils to be adsorbed by crop roots and then accumulated in crops, which eventually causes great health risk when the crops are ingested by humans. Thus, it is valuable to understand the enrichment model of heavy metals in crops. Diffusive gradients in thin-films (DGT) technique, as an in-situ passive sampling method, can be used to evaluate the bioavailable heavy metals contents in soils. In this study, data of the bioavailable cadmium (Cd) in soils determined by DGT and Cd contents uptake in rice and maize grains in Tianjin, Zhejiang and Guangxi provinces of China were collected from previous references in Web of Science. By comparing bioconcentration factors, it was found that the heavy metal concentrations accumulated in rice and maize followed a general order roots > stems or leaves > grains. An accurate and robust model for the prediction of Cd content in maize and rice grains was established based on bioconcentration factor (BCF) and the bioavailable Cd content determined by DGT method, with R2 0.986 and root mean square error (RMSE) 0.128. This result suggests that the DGT method can be good tool for predicting heavy metals uptake in crops.


Assuntos
Oryza , Poluentes do Solo , Bioacumulação , Disponibilidade Biológica , Cádmio/análise , China , Humanos , Solo , Poluentes do Solo/análise , Zea mays
12.
Environ Sci Pollut Res Int ; 28(41): 57970-57982, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34100212

RESUMO

Beijing, as the capital of China, still has soil pollution problems that cannot be ignored. However, there are few studies on the overall ecological risks of heavy metals in farmland soils in Beijing. This study selected 432 soils and crops heavy metal content data of eight districts in Beijing from academic papers and academic journal papers. In this study, the improved Hakanson method, improved analytic hierarchy process (AHP), and integrated quality impact index (IICQ) comprehensively were used to evaluate the impact of Pb, As, and Cd pollution on the farmland soil environment, and the applicable conditions of these methods were discussed. The results by improved Hakanson method showed that both Pb and As were at the normal ecological risk level, while Cd was the largest contributor to potential ecological risk which accounted for 72.54% of the total risk and is mainly at a moderate ecological risk level. The analysis by improved AHP showed that the average comprehensive index of soil heavy metal pollution in the study area was 0.2317, which was at a light pollution level. The IICQ of soil and agricultural products were between 0 and 1 demonstrating that the soil was clean. In summary, the pollution of heavy metals Pb, As, and Cd in the study area is at a relatively low level, and there is no significant risk to the surrounding environment and human health. IICQ method is suitable for the evaluation of soil heavy metal composition and individual impact and can be more accurately used for the overall ecological evaluation of soil-crop-human health system.


Assuntos
Metais Pesados , Poluentes do Solo , Pequim , China , Monitoramento Ambiental , Fazendas , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
13.
ACS Appl Mater Interfaces ; 13(12): 14028-14036, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33730480

RESUMO

Aß1-42-conjugated magnetic nanoparticles, Aß1-42@MNP, were prepared by covalently coupling Aß1-42 to hyperbranched polyethyleneimine (PEI)-modified magnetic nanoparticles via N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC). Aß1-42's high binding capacity to glycosyl groups facilitates Aß1-42@MNP composite to be a promising selective adsorbent for glycoproteins in egg whites. In our study, under conditions of pH 4.0, the adsorption efficiency of Aß1-42@MNP composite for ovalbumin (100 µg mL-1) was 98.4% and its maximum adsorption capacity was 344.8 mg g -1; under the condition of pH 4.0 and 200 mmol L-1 NaCl, its adsorption efficiencies for ovalbumin and ovotransferrin were 96.9% and 60.0%, respectively. According to these primary data, in practice, ovalbumin was removed from egg white by Aß1-42@MNP composite at pH 4.0 (step I), and then after adding NaCl until the final salt concentration reached 200 mmol L-1 (pretreated egg white), we utilized the same adsorbent to further isolate/purify glycoproteins (step II). SDS-PAGE results showed that Aß1-42@MNP composite could largely remove ovalbumin in step I and could isolate/purify the remaining ovalbumin and ovotransferrin in step II. LC-MS/MS analysis results showed that the removal of ovalbumin reduced its percentage in egg white samples from 32.93% to 11.05% in step I and the remaining ovalbumin and ovotransferrin were enriched in step II, where the final percentage reached 11.6% and 12.6%, respectively. In summary, 81 protein species were identified after two-step extraction with Aß1-42@MNP on egg white, while only 46 protein species were identified directly from raw egg white without any pretreatment. This work well illustrates the excellent adsorption performance of Aß1-42@MNP composite to glycoproteins and its potential in the application of proteomic studies on low-abundance proteins in egg white.


Assuntos
Peptídeos beta-Amiloides/química , Proteínas do Ovo/isolamento & purificação , Glicoproteínas/isolamento & purificação , Proteínas Imobilizadas/química , Nanopartículas de Magnetita/química , Fragmentos de Peptídeos/química , Animais , Bovinos , Fracionamento Químico , Galinhas , Clara de Ovo/química , Nanopartículas de Magnetita/ultraestrutura , Modelos Moleculares
14.
Environ Toxicol Chem ; 40(6): 1559-1569, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33651400

RESUMO

Sodium alginate-polyglutamic acid was used to develop a new diffusive gradient in thin films (SA-PGA-DGT) device, which was proven to be suitable for the investigation of labile Cd in soil. The adsorption capacity of Cd was calculated to be approximately 16.8 µg/cm2 , which was hardly affected by factors including pH (5-9), ionic strength (0.1-100 mM), and the presence of other metals (Pb, Cu, Ni, and Cr). The SA-PGA gel has dense and uneven pores with large specific surface area, which ensures the adsorption of Cd by functional groups of the gel. A kinetics study indicated that the adsorption rate of Cd by the binding gel can be described as a pseudo-second-order reaction. Deployment of the SA-PGA-DGT in the soils of Tang Gu (located in Binhai New District, Tianjin, China) showed a strong positive linear correlation between Cd measured by the device and exchangeable Cd measured by the Tessier method (R = 0.73, p < 0.01). Cadmium determined by the SA-PGA-DGT device was less affected by soil properties. This new SA-PGA-DGT has obvious advantages over other methods in respect of the labile Cd analysis in soil. The innovative novel device expands the variety of existing DGT technologies and can be utilized to monitor the level of labile Cd in soil effectively. Environ Toxicol Chem 2021;40:1559-1569. © 2021 SETAC.


Assuntos
Cádmio , Poluentes do Solo , Alginatos , Cádmio/análise , Monitoramento Ambiental/métodos , Ácido Poliglutâmico , Solo/química , Poluentes do Solo/análise
15.
J Hazard Mater ; 411: 124837, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33450634

RESUMO

Tianjin, as an important maize production region in China, has a long history of sewage irrigation resulting in the soil cadmium (Cd) contamination. In this study, single extractions of CaCl2 and HNO3, BCR sequential extraction and the diffusive gradients in thin films technique (DGT) were used to measure the bioavailable Cd content in soils. The Cd content in soil samples all exceeded the background values, with 14.3% and 33.3% of sites in the Baodi District (BDD) and Jinghai District (JHD) exceeding the risk control values, respectively. The average content of Cd in maize samples is lower than the pollution control values, which may be related to the higher pH (8.53) and organic matter (OM) content (15.01 g kg-1) in soils. Bioavailable Cd measured by DGT correlated well with Cd in maize grains (R2 =0.92). The DGT and DIFS model predicted the metals release from the agricultural lands, the total concentration of Cd in soil was relatively low, but the labile Cd in the soils has adequate metal release capability. This study shows that DGT is efficient in predicting Cd accumulation in grains from contaminated soils.


Assuntos
Cádmio , Poluentes do Solo , Disponibilidade Biológica , Cádmio/análise , China , Monitoramento Ambiental , Solo , Poluentes do Solo/análise , Zea mays
16.
Nat Prod Res ; 35(9): 1518-1524, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31448638

RESUMO

The investigation of chemical constituents from the leaves and seeds of Vitex negundo var. heterophylla resulted in the isolation of one new phenolic glycoside, vitexnegheteroin M (1), together with eleven known compounds (2-12). Their structures were elucidated through extensive spectroscopic analyses including 1D, 2D NMR, HR-ESI-MS, and by comparison with the literature. Among them, compound 3 was obtained from the Vitex genus for the first time, and compounds 4-8, and 10-12 were isolated from this plant for the first time. Their anti-inflammatory activities were investigated by measuring nitric oxide (NO) production in lipopolysaccharide (LPS)-induced murine microglial BV-2 cells. As the obtained results, compound 9 showed the strongest inhibitory activity against LPS-stimulated NO production in BV-2 cells with IC50 value ranging from 8.65 ± 0.67 µM.


Assuntos
Glicosídeos/isolamento & purificação , Fenóis/isolamento & purificação , Vitex/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Linhagem Celular , Glicosídeos/análise , Glicosídeos/química , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/efeitos dos fármacos , Óxido Nítrico/biossíntese , Fenóis/análise , Fenóis/química , Folhas de Planta/química , Espectroscopia de Prótons por Ressonância Magnética , Sementes/química
17.
Water Res ; 185: 116290, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32818733

RESUMO

Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) were investigated from effluent of two hospital and two municipal wastewater treatment plants (WWTPs) before and after disinfection. The results of network analysis showed that 8 genera were identified to be the main potential hosts of ARGs, including Mycobacterium, Ferruginibacter, Thermomonas, Morganella, Enterococcus, Bacteroides, Myroides and Romboutsia. The removal of ARGs and their possible bacterialhosts were synchronous and consistent by chlorine or ultraviolet (UV) disinfection in WWTPs. The mechanisms of ARB and ARGs removal, and conjugation transfer of RP4 plasmids by UV, chlorine and synergistic UV/chlorine disinfection was revealed. Compared to UV alone, ARB inactivation was improved 1.4 log and photoreactivation was overcomeeffectively by UV/chlorine combination (8 mJ/cm2, chlorine 2 mg/L). However, ARGs degradation was more difficult than ARB inactivation. Until UV dosage enhanced to 320 mJ/cm2, ARGs achieved 0.58-1.60 log removal. Meanwhile, when 2 mg/L of chlorine was combined with UV combination, ARGs removal enhanced 1-1.5 log. The synergistic effect of adding low-dose chlorine (1-2 mg/L) during UV radiation effectively improved ARB and ARGs removal simultaneously. The same synergistic effect also occurred in the horizontal gene transfer (HGT). Non-lethal dose chlorine (0.5 mg/L) increased the conjugation transfer frequency,which confirmed that the mRNA expression levels of type IV secretion system (T4SS) proteins vir4D, vir5B and vir10B were significantly enhanced. The risk of RP4 plasmid conjugation transfer was significantly reduced with UV/chlorine (UV ≥ 4 mJ/cm2, chlorine ≥ 1 mg/L). These findings may serve as valuable implications for assessing and controlling the risk of ARGs transfer and propagation in the environment.


Assuntos
Bactérias , Cloro , Antibacterianos/farmacologia , Bactérias/genética , Desinfecção , Farmacorresistência Bacteriana , Resistência Microbiana a Medicamentos , Genes Bacterianos , Águas Residuárias
18.
Sci Total Environ ; 738: 139802, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32535279

RESUMO

Artificial recharge to groundwater with reclaimed water is considered a promising method to alleviate groundwater depletion and over-exploitation. However, the occurrence of fluoroquinolone antibiotics (FQs) was ubiquitous in wastewater, surface water, groundwater and even drinking water threating human health and ecology. In this study, the occurrence of six selected FQs in reclaimed water effluent and their removal by tertiary treatment units were investigated. The overall removal efficiencies in average of the tertiary treatment processes in Beijing and Changzhou were ranging from 21.2% to 55.2%. Activated carbon exhibited better performance for FQs removal than ozone and biological treatment such as membrane bioreactor, anaerobic-anoxic-oxic and biofilter. The results of two pilot study showed that the impact of reclaimed water to groundwater quality in terms of FQs concentration by direct injection in GBD was stronger than surface spreading in Changzhou, which might be due to the recharge strategy and the physical and chemical characteristics of sediment and aquifer soil. The hazard quotient (HQ) values of ofloxacin (OFL) in reclaimed water was up to 12.54, indicating the extreme eco-toxicological risk, while enrofloxacin (ENR) exhibited medium risk. After recharge with reclaimed water, the HQ values of OFL and ENR in groundwater ranged from low to medium ecological risk to the environment. Thus, the FQs in reclaimed water need to be paid more attention during their reuse for groundwater recharge, especially by direct injection. It is suggested that FQs should be considered in the priority substances lists in standards and guidelines of reclaimed water reuse for groundwater recharge to ensure the safety of groundwater.


Assuntos
Água Subterrânea , Poluentes Químicos da Água/análise , Antibacterianos/análise , Pequim , Fluoroquinolonas/análise , Humanos , Projetos Piloto , Medição de Risco , Águas Residuárias , Água
19.
Mol Nutr Food Res ; 64(10): e1900706, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32239630

RESUMO

SCOPE: Maca (Lepidium meyenii), a well-known plant from the Andean highlands of Peru, has been used widely as a nutritional supplement to increase sexual function and fecundity. However, the identity of its active ingredients and how they function remain unknown. METHODS AND RESULTS: Chemical substances in maca are identified by UPLC-Q-TOF, and the active ingredients are screened through HotMap coupled with an artificial neural network. Lepidiline A (LA), an imidazole alkaloid, is identified as the key active compound. LA affects the balance of endogenous sex hormones in mice and improves fecundity in Drosophila. Using a molecular LA probe, 17ß-hydroxysteroid dehydrogenase type 1 (HSD17B1) is revealed to be the potential target of LA using a fishing-rod strategy. It is demonstrated with experimental data that LA targets HSD17B1 to enhance the enzyme's activity and increases its bioconversion efficiency of actively formed sex hormones including estrogen to 17ß-estradiol and 4-androsten-3,7-dione to testosterone, which ultimately improves reproductive activity. CONCLUSION: LA improves the balance of endogenous sex hormones and increases fecundity by targeting HSD17B1. This underlying mechanism of action provides a useful insight into the application of maca in the regulation of dietary nutrition and healthy fertility.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Estradiol Desidrogenases/metabolismo , Fertilidade/efeitos dos fármacos , Hormônios Esteroides Gonadais/metabolismo , Lepidium/química , Alcaloides/análise , Alcaloides/química , Animais , Células CHO , Cricetulus , Drosophila melanogaster/fisiologia , Feminino , Masculino , Camundongos
20.
ACS Appl Mater Interfaces ; 11(21): 19096-19103, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31075199

RESUMO

We demonstrate a sustainable and cost-effective route to fabricate high-sulfur-loading cathode materials with the cooperative interfaces of "sulfiphilic" and "lithiophilic" sites from the removal industry of the pollutant H2S gas. The MgO-impregnated and nitrogen-doped mesoporous carbon composite desulfurizers (NMC/MgO), acting as effective catalysts and large storehouses, could catalytically oxidize H2S into elemental S with high catalytic selectivity and sulfur capacity. The obtained byproduct NMC/MgO/S-CO composites possess high sulfur loading (73.8 wt %) and significant structure advantages for practical application in Li-S batteries. First, the uniform distribution of S in the NMC/MgO frameworks via the in situ catalytic oxidation approach could offer large interface area for charge transport and Li+ reaction. Then, the cooperative effects of the "sulfiphilic" MgO nanoparticles and the "lithiophilic" nitrogen dopants in the NMC/MgO could effectively suppress the polysulfide shuttling. Under the further assistance of physical confinement of the mesoporous NMC/MgO, the NMC/MgO/S-CO composites present excellent electrochemical performances with a high reversible capacity of 772 mAh g-1 and a Coulombic efficiency of 93.6% at the 100th cycle at 0.2 C. These encouraging results not only develop a sustainable way to turn waste into wealth but also provide a promising strategy to product high-sulfur-loading cathode materials with uniform distribution of S through the in situ catalytic strategy for high-performance Li-S batteries.

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