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1.
Asia Pac J Clin Nutr ; 33(1): 83-93, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494690

RESUMO

BACKGROUND AND OBJECTIVES: To explore the risk factors for non-alcoholic fatty liver disease (NAFLD) and to establish a non-invasive tool for the screening of NAFLD in an older adult population. METHODS AND STUDY DESIGN: A total of 131,161 participants were included in this cross-sectional study. Participants were randomly divided into training and validation sets (7:3). The least absolute shrinkage and selection operator method was used to screen risk factors. Multivariate logistic regression was employed to develop a nomogram, which was made available online. Receiver operating characteristic curve analysis, calibration plots, and decision curve analysis were used to validate the discrimination, calibration, and clinical practicability of the nomogram. Sex and age subgroup analyses were conducted to further validate the reliability of the model. RESULTS: Nine variables were identified for inclusion in the nomogram (age, sex, waist circumference, body mass index, exercise frequency, systolic blood pressure, fasting plasma glucose, alanine aminotransferase, and low-density lipoprotein cholesterol). The area under the receiver operating characteristic curve values were 0.793 and 0.790 for the training set and the validation set, respectively. The calibration plots and decision curve analyses showed good calibration and clinical utility. Subgroup analyses demonstrated consistent discriminatory ability in different sex and age subgroups. CONCLUSIONS: This study established and validated a new nomogram model for evaluating the risk of NAFLD among older adults. The nomogram had good discriminatory performance and is a non-invasive and convenient tool for the screening of NAFLD in older adults.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Idoso , Humanos , China/epidemiologia , Estudos Transversais , Nomogramas , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Reprodutibilidade dos Testes , Fatores de Risco
2.
ACS Appl Mater Interfaces ; 15(16): 20141-20150, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37058551

RESUMO

Metals and their compounds effectively suppress the polysulfide shuttle effect on the cathodes of a lithium-sulfur (Li-S) battery by chemisorbing polysulfides and catalyzing their conversion. However, S fixation on currently available cathode materials is below the requirements of large-scale practical application of this battery type. In this study, perylenequinone was utilized to improve polysulfide chemisorption and conversion on cobalt (Co)-containing Li-S battery cathodes. According to IGMH analysis, the binding energies of DPD and carbon materials as well as polysulfide adsorption were significantly enhanced in the presence of Co. According to in situ Fourier transform infrared spectroscopy, the hydroxyl and carbonyl groups in perylenequinone are able to form O-Li bonds with Li2Sn, facilitating chemisorption and catalytic conversion of polysulfides on metallic Co. The newly prepared cathode material demonstrated superior rate and cycling performances in the Li-S battery. It exhibited an initial discharge capacity of 780 mAh g-1 at 1 C and a minimum capacity decay rate of only 0.041% over 800 cycles. Even with a high S loading, the cathode material maintained an impressive capacity retention rate of 73% after 120 cycles at 0.2 C.

3.
Fish Physiol Biochem ; 48(4): 1039-1055, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35831485

RESUMO

Although diquat is a widely used water-soluble herbicide in the world, its sublethal adverse effects to fish have not been well characterised. In this study, histopathological examination and biochemical assays were applied to assess hepatotoxicity and combined with gas chromatography-mass spectrometry (GC-MS)-based metabolomics analysis to reveal overall metabolic mechanisms in the liver of zebrafish (Danio rerio) after diquat exposure at concentrations of 0.34 and 1.69 mg·L-1 for 21 days. Results indicated that 1.69 mg·L-1 diquat exposure caused cellular vacuolisation and degeneration with nuclear abnormality and led to the disturbance of antioxidative system and dysfunction in the liver. No evident pathological injury was detected, and changes in liver biochemistry were not obvious in the fish exposed to 0.34 mg·L-1 diquat. Multivariate statistical analysis revealed differences between profiles obtained by GC-MS spectrometry from control and two treatment groups. A total of 17 and 22 metabolites belonging to different classes were identified following exposure to 0.34 and 1.69 mg·L-1 diquat, respectively. The metabolic changes in the liver of zebrafish are mainly manifested as inhibition of energy metabolism, disorders of amino acid metabolism and reduction of antioxidant capacity caused by 1.69 mg·L-1 diquat exposure. The energy metabolism of zebrafish exposed to 0.34 mg·L-1 diquat was more inclined to rely on anaerobic glycolysis than that of normal zebrafish, and interference effects on lipid metabolism were observed. The metabolomics approach provided an innovative perspective to explore possible hepatic damages on fish induced by diquat as a basis for further research.


Assuntos
Herbicidas , Poluentes Químicos da Água , Animais , Diquat/metabolismo , Diquat/toxicidade , Embrião não Mamífero/metabolismo , Herbicidas/toxicidade , Fígado/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo
4.
Environ Technol ; 43(16): 2516-2529, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33512309

RESUMO

Heavy metal immobilization using biochar (BC) is different from the usual soil incubation due to the low molecular weight organic acids (LMWOAs) in the rhizosphere and is an issue worth evaluating. Therefore, the impacts of rice husk BC (5%), tartaric acid, and oxalic acid, coupled with combinations of BC and tartaric acid/oxalic acid on the transformation of cadmium (Cd), lead (Pb), and zinc (Zn) among their geochemical forms, including their bioavailability in a metal-contaminated soil, were investigated in an incubation experiment. The application of BC, low concentration of tartaric acid (2 mmol kg-1 soil) (TA2), and the combined BC plus a low level of tartaric acid (BC-TA2) markedly reduced the acid-soluble and available (CaCl2-extractable) Cd, Pb, and Zn compared to control (CK) in which BC-TA2 was found to be the most effective treatment. The trends were reversed in the case of the high concentrations of tartaric acid (>5-20 mmol kg-1 soil), all levels of oxalic acid (2-20 mmol kg-1 soil), and the combined BC plus high levels of tartaric acid/oxalic acid treatments. The BC-TA2 transformed the highest amounts of acid-soluble and reducible Cd, Pb, and Zn to the oxidizable and residual fractions with incubation time. The results suggested that the low concentration of tartaric acid enhanced Cd, Pb, and Zn immobilization, while the higher level of tartaric acid and all concentrations of oxalic acid increased their mobilization. In conclusion, BC-TA2 could immobilize the most heavy metals and serve as an amendment for metals' immobilization/redistribution in contaminated soils.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Ácidos/metabolismo , Cádmio/química , Carvão Vegetal/química , Chumbo/metabolismo , Metais Pesados/análise , Peso Molecular , Compostos Orgânicos/metabolismo , Oryza/química , Oxalatos/metabolismo , Solo/química , Poluentes do Solo/química , Zinco/química
5.
Sci Total Environ ; 730: 139119, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32402973

RESUMO

Biochars are widely used in the remediation of soil heavy metals, but there has been no clear understanding to the effects of novel co-pyrolysis biochars derived from biomass and orthophosphate on soil heavy metals. In this study, co-pyrolysis biochars derived from rape straw and orthophosphate (Ca (H2PO4)2·H2O/KH2PO4) were prepared and used to explore their effects on the speciations and ecological risks of Pb, Cd, and Cu in contaminated agricultural soil. The results showed that the addition of these co-pyrolysis biochars significantly decreased TCLP extracted concentrations (decreased by 5.9-81.7%) and ecological risks of heavy metals (Pb, Cd, and Cu) by transforming the metals from available speciation to stable speciation in soils. Co-pyrolysis biochar derived from rape straw and KH2PO4 showed the highest immobilization capacities, and the immobilization capacities of biochars for three metals were in the order of Pb > Cu > Cd. Co-pyrolysis biochars could precipitate and complex with heavy metals directly by the phosphate and -OH on their surface, and also could promote immobilization of heavy metals indirectly by increasing soil pH value and available P content. During incubation, the content of carboxyl groups on biochars increased significantly, which was beneficial to the further complexation of heavy metals. In summary, the application of co-pyrolysis biochar derived from rape straw and orthophosphate (especially for KH2PO4) could effectively reduce ecological risks of Pb, Cd, and Cu in contaminated soil.


Assuntos
Poluentes do Solo/análise , Cádmio , Carvão Vegetal , Cobre , Chumbo , Metais Pesados , Fosfatos , Pirólise , Solo
6.
Plant Physiol ; 183(1): 123-136, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32139476

RESUMO

The lignin biosynthetic pathway is highly conserved in angiosperms, yet pathway manipulations give rise to a variety of taxon-specific outcomes. Knockout of lignin-associated 4-coumarate:CoA ligases (4CLs) in herbaceous species mainly reduces guaiacyl (G) lignin and enhances cell wall saccharification. Here we show that CRISPR-knockout of 4CL1 in poplar (Populus tremula × alba) preferentially reduced syringyl (S) lignin, with negligible effects on biomass recalcitrance. Concordant with reduced S-lignin was downregulation of ferulate 5-hydroxylases (F5Hs). Lignification was largely sustained by 4CL5, a low-affinity paralog of 4CL1 typically with only minor xylem expression or activity. Levels of caffeate, the preferred substrate of 4CL5, increased in line with significant upregulation of caffeoyl shikimate esterase1 Upregulation of caffeoyl-CoA O-methyltransferase1 and downregulation of F5Hs are consistent with preferential funneling of 4CL5 products toward G-lignin biosynthesis at the expense of S-lignin. Thus, transcriptional and metabolic adaptations to 4CL1-knockout appear to have enabled 4CL5 catalysis at a level sufficient to sustain lignification. Finally, genes involved in sulfur assimilation, the glutathione-ascorbate cycle, and various antioxidant systems were upregulated in the mutants, suggesting cascading responses to perturbed thioesterification in lignin biosynthesis.


Assuntos
Lignina/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo , Xilema/metabolismo , Carboxiliases/genética , Carboxiliases/metabolismo , Catálise , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/genética , Xilema/genética
7.
Chemosphere ; 244: 125418, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31812043

RESUMO

Although rice straw (RS), biochar (BI) and calcite (CC) have proved to be effective immobilizing agents in acidic contaminated soil, we lack up-to-date scientific data regarding nickel (Ni) fractionation in soil and removal capacity in water. Therefore, an incubation study was undertaken to investigate the efficacy of RS, BI and CC with three application rates (0, 1 and 2%) of RS, BI and CC on the immobilization of Ni in polluted soil. Various extraction techniques were carried out: sequential extraction procedure, the European Community Bureau of Reference (BCR), extraction with CaCl2, and the toxicity characteristics leaching procedure (TCLP) techniques. Additionally, Ni sorption behavior was determined using the Langmuir and Freundlich isotherms. Results showed that adding all amendments into Ni contaminated acidic soil, enhanced soil pH, reduced the exchangeable fraction of Ni by 48%-55%, 59%-71% and 58%-66.3%, when RS, BI and CC were applied at 1% and 2% rates, respectively. According to the Langmuir adsorption isotherm results, the maximum sorption capacity was recorded using 2747 mg kg-1 in 2% CC amended soil. However, biochar exhibited the maximum Ni sorption capacity (13348 mg kg-1), due to its porous structure, larger surface area, and having more functional groups. Furthermore, the results of FTIR, SEM and zeta potential techniques confirmed that the immobilization and biochar's capacity to remove Ni were more effective when compared to other immobilizing agents.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Níquel/química , Poluentes do Solo/química , Adsorção , Carbonato de Cálcio , Fracionamento Químico , Poluição Ambiental , Oryza/química , Solo/química , Poluentes do Solo/análise , Água
8.
Sci Total Environ ; 699: 134262, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31677473

RESUMO

Chemical oxidation is an effective method to improve the ability of biochars for metals removal, but there are too few studies on screening of high-efficiency oxidants and quantitative analysis of sorption mechanisms. In this study, rape straw biochars (BC) were oxidized with HNO3, H2O2, and KMnO4, and noted as BC-HNO3, BC-H2O2, and BC-Mn, respectively. The Pb removal capacities and quantitative sorption mechanisms of biochars were explored through batch sorption experiments. Compared with that of BC (175 mmol kg-1), the maximum Pb sorption capacities of BC-HNO3 and BC-H2O2 increased to 526 and 917 mmol kg-1, in which contribution of surface complexation accounted for 55.1% and 39.0%, respectively. Due to the large surface area and abundant newly formed MnO2, BC-Mn showed the maximum Pb sorption capacity of 1343 mmol kg-1, and its high removal efficiency appeared even at low pH value (pH = 2) and high initial Pb concentration (1.0 mol L-1). The contribution of cation exchange accounted for 97.4% of the Pb sorption by BC-Mn. These results suggested BC-Mn had great potential for Pb removal from aqueous solution, and the quantitative analyses of sorption mechanisms revealed the contribution of each mechanism and provided a basis for evaluating application prospects of biochars.


Assuntos
Carvão Vegetal/química , Chumbo/química , Modelos Químicos , Brassica rapa , Oxirredução
9.
J Hazard Mater ; 371: 191-197, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30851672

RESUMO

When used separately, biochar and orthophosphate are good materials to remove Pb from water, but few studies have been done on Pb removal by biochar-orthophosphate composite. Here biochar-orthophosphate composites were prepared by co-pyrolyzing rape straw with orthophosphate (Ca(H2PO4)2·H2O / KH2PO4) at ratio of 5:1 (W:W), noted as WBC-Ca and WBC-K, respectively, so as to explore the Pb removal capacities and mechanisms of co-pyrolysis biochars. The sorption isotherms of Pb were well fitted with Langmuir model and the maximum sorption capacities of Pb by original biochar, WBC-Ca, and WBC-K were 184.1, 566.3 and 1559 mmol kg-1, respectively. The results of FTIR, XRD, and XPS analyses showed that phosphorus in biochar played an important role to remove Pb by forming lead-precipitates. However, the species of lead-precipitates in three types of Pb-loaded biochars were Pb5(PO4)3Cl, Pb2P2O7, and Pbn/2(PO3)n, individually, and that was because speciation of phosphorus had undergone significant thermochemical transformation during pyrolysis process. Orthophosphate in WBC-Ca was mainly transformed to pyrophosphate, while orthophosphate in WBC-K was transformed to both metaphosphate and pyrophosphate. The present results warrant the promising application of co-pyrolysis biochar derived from rape straw and orthophosphate in removal of Pb from wastewater.


Assuntos
Brassica rapa/metabolismo , Carvão Vegetal , Chumbo/isolamento & purificação , Fosfatos/metabolismo , Pirólise
10.
Ecotoxicol Environ Saf ; 174: 401-407, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30851537

RESUMO

The contamination of soil by copper (Cu) and lead (Pb) is a serious concern because of its high health risk via the food chain. Oxalic acid-activated phosphate rock (APR) and bone meal (BM) were applied to Cu and Pb co-contaminated soil to investigate their efficacy in the immobilization of Cu and Pb. APR and BM were applied into the contaminated soil (158.8 mg/kg total Pb and 573.2 mg/kg Cu) at four levels of dosages (0.1%, 0.5%, 2%, and 4%) and incubated for one year. The results demonstrated that the acid exchangeable Pb fraction in the soil treated with APR and BM decreased compared to the control, while there was no noticeable change in the acid-exchangeable Cu fraction in the soil treated with either APR or BM. Meanwhile, the application of BM and APR increased the fraction of residual Cu and Pb in the polluted soils. Moreover, the addition of either APR or BM at the dose of 4% decreased the concentrations of CaCl2-extractable Cu and Pb in the amended soil, and the percentages of that reduction in the APR amended soils were 56% and 91% and in BM amended soils were 67% and 64%, respectively. The immobilization of Cu and Pb by APR and BM might be induced by the increased soil pH and soluble P contents in the amended soils. In general, BM is more effective than APR on the immobilization of Cu in polluted soil, while APR had greater efficiency than BM on the immobilization of Pb when the levels of amendments were above 2%.


Assuntos
Metais Pesados/análise , Minerais/química , Mineração , Ácido Oxálico/química , Fosfatos/química , Poluentes do Solo/análise , Solo/química , Produtos Biológicos/química , China , Cobre/análise , Chumbo/análise , Modelos Teóricos
11.
ChemSusChem ; 11(13): 2045-2050, 2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29719142

RESUMO

Lignin, the planet's most abundant renewable source of aromatic compounds, is difficult to degrade efficiently to welldefined aromatics. We developed a microwave-assisted catalytic Swern oxidation system using an easily prepared catalyst, MoO2 Cl2 (DMSO)2 , and DMSO as the solvent and oxidant. It demonstrated high efficiency in transforming lignin model compounds containing the units and functional groups found in native lignins. The aromatic ring substituents strongly influenced the selectivity of ß-ether phenolic dimer cleavage to generate sinapaldehyde and coniferaldehyde, monomers not usually produced by oxidative methods. Time-course studies on two key intermediates provided insight into the reaction pathway. Owing to the broad scope of this oxidation system and the insight gleaned with regard to its mechanism, this strategy could be adapted and applied in a general sense to the production of useful aromatic chemicals from phenolics and lignin.

12.
Huan Jing Ke Xue ; 38(1): 361-367, 2017 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965067

RESUMO

A compound contaminated soil sampled from Lingxiang City,Hunan Province,was used to investigate the effects of biochar (BC) and montmorillonite (MM) addition on heavy metals fractions.The addition amounts of BC and MM were 1%,2%,5%,respectively,and the mixture treatment was 1% BC+1% MM.BCR (European Community Bureau of Reference) sequential extraction method was used to assess the fractions of heavy metals in soil after incubation.The results indicated that adding BC alone significantly reduced the available contents of Pb,Cu and Cd.Among montmorillonite treatments,MM5% treatment decreased the weak acid extractable content of Cu,Pb,Zn,Cd by 27.6%,19.2%,25.6%,19.2%,respectively.BC+MM treatment worked well,decreased the weak acid extractable content of Cu,Pb,Zn,Cd by 15.8%,15.9%,13.1%,12.0%,and increased the residual content by 39.0%,110.1%,9.6%,62.5%,significantly reducing the mobility of the four elements.For the stabilization effect,MM treatment worked better than BC treatment,and a combination of two amendments worked the best.


Assuntos
Bentonita , Carvão Vegetal , Metais Pesados/análise , Poluentes do Solo/análise , China , Cidades , Solo
13.
J Agric Food Chem ; 64(41): 7782-7788, 2016 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-27690421

RESUMO

Linking lignin model compounds to carrier proteins is required either to raise antibodies to them or to structurally screen antibodies raised against lignins or models. This paper describes a flexible method to link phenolic compounds of interest to cationic bovine serum albumin (cBSA) without interfering with their important structural features. With the guaiacylglycerol-ß-guaiacyl ether dimer, for example, the linking was accomplished in 89% yield with the number of dimers per carrier protein being as high as 50; NMR experiments on a 15N- and 13C-labeled conjugation product indicated that 13 dimers were added to the native lysine residues and the remainder (∼37) to the amine moieties on the ethylenediamine linkers added to BSA; ∼32% of the available primary amine groups on cBSA were therefore conjugated to the hapten. This loading is suitable for attempting to raise new antibodies to plant lignins and for screening.

14.
Environ Sci Pollut Res Int ; 23(22): 23271-23280, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27638790

RESUMO

The efficiency of five different single leaching reagents (tartaric acid (TA), citric acid (CA), CaCl2, FeCl3, EDTA) and two different composite leaching reagents (CA + FeCl3, CA + EDTA) on removing Cu, Pb, Zn, and Cd from contaminated paddy soil in Hunan Province (in China) was studied. The results indicated that the efficiencies of CA, FeCl3, and EDTA on extracting Cu, Pb, Cd, and Zn from soil were greater than that of TA and CaCl2, and their extraction efficiencies were EDTA ≥ FeCl3 > CA. The efficiencies of CA + FeCl3 on extracting Cu, Pb, Cd, and Zn were higher than that of single CA or FeCl3. The 25 mmol L-1 CA + 20 mmol L-1 FeCl3 was a promising composite leaching reagent for paddy soil, and it could remove Cu (57.6 %), Pb (59.3 %), Cd (84.8 %), and Zn (28.0 %), respectively. With the same amount of leaching reagent, the efficiency of continuous leaching by several times was higher than that by once. In addition, the easily reducible and oxidizable fractions of heavy metals showed significant decrease during the process of leaching.


Assuntos
Metais Pesados/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Solo/química , Ácido Cítrico/química , Poluição Ambiental
15.
J Org Chem ; 75(9): 3144-6, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20384382

RESUMO

The cationic ruthenium catalyst Ru(3)(CO)(12)/NH(4)PF(6) was found to be highly effective for the intermolecular coupling reaction of pyrroles and terminal alkynes to give gem-selective alpha-vinylpyrroles. The carbon isotope effect on the alpha-pyrrole carbon and the Hammett correlation from a series of para-substituted N-arylpyrroles (rho = -0.90) indicate a rate-limiting C-C bond formation step of the coupling reaction.


Assuntos
Alcinos/química , Compostos Organometálicos/química , Pirróis/síntese química , Rutênio/química , Catálise , Estrutura Molecular , Estereoisomerismo
16.
Organometallics ; 28(22): 6585-6592, 2009 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-20161379

RESUMO

The ruthenium-hydride complex (PCy(3))(2)(CO)RuHCl was found to be a highly effective catalyst for the alkyne-to-carboxylic acid coupling reaction to give synthetically useful enol ester products. Strong solvent effect was observed for the ruthenium catalyst in modulating the activity and selectivity; the coupling reaction in CH(2)Cl(2) led to the regioselective formation of gem-enol ester products, while the stereoselective formation of (Z)-enol esters was obtained in THF. The coupling reaction was found to be strongly inhibited by PCy(3). The coupling reaction of both PhCO(2)H/PhC identical withCD and PhCO(2)D/PhC identical withCH led to the extensive deuterium incorporation on the vinyl positions of the enol ester products. An opposite Hammett value was observed when the correlation of a series of para-substituted p-X-C(6)H(4)CO(2)H (X = OMe, CH(3), H, CF(3), CN) with phenylacetylene was examined in CDCl(3) (rho = +0.30) and THF (rho = -0.68). Catalytically relevant Ru-carboxylate and -vinylidene-carboxylate complexes, (PCy(3))(2)(CO)(Cl)Ru(kappa(2)-O(2)CC(6)H(4)-p-OMe) and (PCy(3))(2)(CO)(Cl)RuC(=CHPh)O(2)CC(6)H(4)-p-OMe, were isolated, and the structure of both complexes was completely established by X-ray crystallography. A detailed mechanism of the coupling reaction involving a rate-limiting C-O bond formation step was proposed on the basis of these kinetic and structural studies. The regioselective formation of the gem-enol ester products in CH(2)Cl(2) was rationalized by a direct migratory insertion of the terminal alkyne via a Ru-carboxylate species, whereas the stereoselective formation of (Z)-enol ester products in THF was explained by invoking a Ru-vinylidene species.

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