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1.
Heliyon ; 10(10): e30829, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38770281

RESUMEN

Klebsiella pneumoniae is an opportunistic pathogen causing severe infections. The circadian rhythm is the internal rhythm mechanism of an organism and plays an important role in coping with changes in the 24-h circadian rhythm. Disruption of the circadian rhythm can lead to immune, behavioral, mental, and other related disorders. Whether K. pneumoniae can disrupt the circadian rhythm after infection remains unclear. Here, we examined the effects of K. pneumoniae NTUH-K2044 infection on biological rhythm and inflammation in zebrafish using behavioral assays, quantitative real-time reverse transcription PCR, neutrophil and macrophage transgenic fish, and drug treatment. The results showed that K. pneumoniae infection decreased the motor activity of zebrafish and reduced the circadian rhythm amplitude, phase, and period. The expression of core circadian rhythm-associated genes increased under light-dark conditions, whereas they were downregulated under continuous darkness. Analysis of Klebsiella pneumoniae-mediated inflammation using Tg(mpx:EGFP) and Tg(mpeg:EGFP) transgenic zebrafish, expressing fluorescent neutrophils and macrophages, respectively, showed increased induction of inflammatory cells, upregulated expression of inflammatory factor genes, and stronger inflammatory responses under light-dark conditions. These effects were reversed by the anti-inflammatory drug G6PDi-1, and the expression of clock genes following K. pneumoniae treatment was disrupted. We determined the relationship among K. pneumoniae, inflammation, and the circadian rhythm, providing a theoretical reference for studying circadian rhythm disorders caused by inflammation.

2.
Water Res ; 257: 121656, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38677110

RESUMEN

Schwertmannite (Sch) is considered as an effective remover of Chromium (Cr) due to its strong affinity for toxic Cr species. Since the instability of Sch, the environmental fate of Cr deserves attention during the transformation of Sch into a more stable crystalline phase. The ubiquitous manganese(II) (Mn(II)) probably affects the transformation of Sch and thus the environmental fate of Cr. Therefore, this study investigated the impact of Mn(II) on the transformation of Cr-absorbed Sch (Cr-Sch) and the associated behavior of SO42- and Cr. We revealed that the transformation products of Cr-Sch at pH 3.0 and 7.0 were goethite and Sch, respectively. The presence of Mn(II) weakened the crystallinity of the transformation products, and the trend was positively correlated with the concentration of Mn(II). However, Mn(II) changed the transformation products of Cr-Sch from hematite to goethite at pH 10.0. Mn(II) replaced Fe(III) in the mineral structures or formed Mn-O complexes with surface hydroxyl groups (-OH), thereby affecting the transformation pathways of Sch. The presence of Mn(II) enhanced the immobilization of Cr on minerals at pH 3.0 and 7.0. Sch is likely to provide an channel for electron transfer between Mn(II) and Cr(VI), which promotes the reduction of Cr(VI). Meanwhile, Mn(Ⅱ) induced more -OH production on the surface of secondary minerals, which played an important role in increasing the Cr fixation. In addition, part of the Mn(Ⅱ) was oxidized to Mn(Ⅲ)/Mn(Ⅳ) at pH 3.0 and pH 7.0. This study helps to predict the role of Mn(II) in the transformations of Cr-Sch in environments and design remediation strategies for Cr contamination.


Asunto(s)
Cromo , Compuestos de Hierro , Manganeso , Minerales , Cromo/química , Manganeso/química , Minerales/química , Compuestos de Hierro/química , Transición de Fase , Concentración de Iones de Hidrógeno , Compuestos Férricos/química
3.
J Environ Manage ; 358: 120883, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38631167

RESUMEN

Applying organic fertilizer is the main way to enhance soil fertility through the interfacial reaction between mineral and dissolved organic matter (DOM). However, the interfacial reaction between minerals and DOM may influence antimony(V) (Sb(V)) mobility in agricultural soils around antimony mines. In our study the ferrihydrite (Fh) was chosen as a representative mineral, to reveal the effect of its interaction with chicken manure organic fertilizer (CM-DOM) with Fh on Sb(V) migration. In this study, we investigated different organic matter molecular weights and C/Fe molar ratios. Our findings indicated that the addition of CM-DOM decreased the adsorption of Sb(V) by Fh and promoted the re-release of Sb(V) adsorbed on Fh. This effect was enhanced by increasing the C/Fe molar ratio. Fh mainly affects its interaction with Sb(V) through electrostatic gravitational interaction and ligand exchange, but the presence of CM-DOM weakens the electrostatic interaction between Fh and Sb(V) as well as competes with Sb(V) for the hydroxyl reactive site on Fh surface. In addition, the smaller molecular weight fraction (<10 kDa) of CM-DOM has higher aromaticity and hydrophobicity, which potentially leads to more intense competition with Sb(V) for the reaction sites on Fh. Therefore, the application of organic fertilizer may promote Sb(V) migration, posing significant risks to soil ecosystems and human health, which should be a concern in field soil cultivation.


Asunto(s)
Antimonio , Pollos , Estiércol , Antimonio/química , Adsorción , Animales , Compuestos Férricos/química , Peso Molecular , Suelo/química , Contaminantes del Suelo/química , Fertilizantes
4.
J Environ Manage ; 355: 120506, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38447514

RESUMEN

Plenty of heavy metals (HMs) that are adsorbed on clay minerals (such as kaolinite), in addition to low molecular-weight organic acids (such as oxalic acid (OA)) with high activities, are widespread in the natural environment. In the present study, the effects of OA on the environmental behaviors of Pb2+/Cd2+ adsorbed by kaolinite have been investigated. The effectiveness and mechanisms of calcium silicate (CS) and magnesium silicate (MS) in reducing the environmental risks of the HMs have also been studied. The results showed that the releases of Pb2+/Cd2+ increased with an increasing concentration of OA. When different dosages of CS/MS were added to the aging system, a redistribution of HMs took place and the free form of Pb2+/Cd2+ decreased to very low levels. Also, the unextractable Pb2+/Cd2+ increased to high levels. Furthermore, a series of characterizations showed that the released HMs were re-captured by the CS/MS. In addition, the CS immobilized the OA in the solution during the aging process, which also facilitated an immobilization of the carbon element in the environment. In general, the present study has contributed to a further understanding of the transport behaviors of the HMs in natural environments, and of the interactions between CS (or MS), the environmental media, and the heavy metal contaminants. In addition, this study has also provided an eco-friendly strategy for an effective remediation of heavy metal pollution.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Caolín , Cadmio , Plomo , Metales Pesados/análisis , Contaminación Ambiental , Contaminantes del Suelo/análisis , Suelo
5.
Sci Total Environ ; 901: 165928, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-37527713

RESUMEN

Nanoplastics (NPs) usually coexist with impurity-bearing ferrihydrite (ImFh), and their interaction is related to their environmental fate. In this study, the aggregation between ImFh (impurities: Al, Mn and Si) and polystyrene nanoplastics (PSNPs), as well as the sedimentation of ImFh-PSNP complex particles in the aqueous phase were investigated systematically with particle concentrations of 100 mg/L ImFh and 10 mg/L PSNPs. Our results revealed that the PSNP suspension was dispersive and stable under various pH values and low ion strength. After coexisting with ImFh, PSNPs aggregated with the positively charged ImFh to form ImFh-PSNP complex particles, which destroyed the stability of PSNPs. The increase in pH and Na+ concentration could inhibit their aggregation, but high Na+ concentration (>20 mM) caused the homoaggregation of PSNPs. The aggregation capacity of PSNPs with ImFh was in the order of Al-bearing Fh > Fh > Mn-bearing Fh > Si-bearing Fh. Zeta potential and Derjaguin-Landau-Verwey-Overbeek (DLVO) calculations indicated that Al-bearing Fh showed higher positive potential than pure Fh, which caused stronger electrostatic interactions with PSNPs. However, Mn and Si in ImFh decreased the positive potential and inhibited the electrostatic interaction with PSNPs, and the effect of Si was greater than that of Mn. The aggregation between ImFh and PSNPs inhibited the sedimentation of their complex particles, and the higher aggregation capacity appeared to have a greater inhibition degree. Due to the "electrostatic patches" effect of PSNPs, the energy barrier of the ImFh-PSNPs particles was higher than that of the ImFh particles. Our findings clarified the influence of impurities on the interaction between ImFh and PSNPs and provided insight regarding their fate in the environment.

6.
J Environ Manage ; 345: 118581, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37451030

RESUMEN

Here, tobermorite was prepared by a solvothermal technology using calcite and quartz with a mixed solvent of ethanol and water. Factors including reaction temperature, time and KOH content were studied to optimize the preparation procedure. To study the relationship between ethanol content-material structural characteristics-adsorption capacity, a series of materials were prepared in different mixed solvent proportions of ethanol and water, and their structural characteristics and adsorption capacity were compared. We found that the adsorption capacity of different samples for Pb2+ and Cd2+ was positively correlated with negatively correlated with the surface area and negatively correlated with the crystallinity of materials. Then, the material prepared by 30% ethanol solution (30-T) with the best adsorption performance was used for further research; the results were fitted by kinetic and thermodynamic models, and adsorbed materials were analyzed by various characterizations, suggesting that the adsorption process was ascribed to comprehensive pathways including ion exchange, chemical precipitation, and surface-complexation. Then, the 30-T was further used to remediate heavy metals contaminated soil, and the remediation effect was examined by the DTPA-extractable method and the European Community Bureau of Reference (BCR) sequential extraction method. The DTPA-extractable results showed that tobermorite observably reduced the bioavailability of Pb and Cd, and the BCR results suggested that the acid-soluble and reducible fractions of Pb and Cd were transformed to the oxidizable and residual fractions after remediation. In summary, tobermorite has great potential in the remediation of heavy metal polluted-aquatic environment/system and soil.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cadmio , Solventes , Agua , Suelo/química , Plomo , Contaminantes del Suelo/química , Metales Pesados/química , Ácido Pentético , Etanol
7.
Chemosphere ; 321: 138123, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36781002

RESUMEN

The water polluted by lead(Pb(II)) and cadmium(Cd(II)) seriously endangers ecological safety and needs to be solved urgently. Because of the relatively low adsorption rate of pure hydroxyapatite for heavy metals, a series of manganese-doped hydroxyapatites (MnHAPs) were prepared by using manganese, a common impurity in hydroxyapatite, as a doping element to improve the adsorption performance. The structural and functional groups of the materials with different Mn/(Ca +Mn) molar ratios (0%, 5%, 10%, 20%, and 30%) were investigated by scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), X-Ray diffraction (XRD), Raman spectrometer and Fourier transform infrared spectroscopy (FTIR) characterization. The presence of manganese influenced the formation and growth of hydroxyapatite crystals, resulting in lattice distortion and a large number of lattice defects in materials. Among them, manganese-doped hydroxyapatite with a Mn/(Ca +Mn) molar ratio of 10% (MnHAP-10) could most effectively remove Pb(II) and Cd(II), with the adsorption capacity of 1806.09 mg g-1 for Pb(II) at pH = 5 and 176.88 mg g-1 for Cd(II) at pH = 5.5. Then the adsorption behavior and mechanism were further researched systemically. It was concluded that the immobilization of Pb(II) by MnHAP-10 was mainly through dissolution precipitation and ion exchange, while Cd(II) was adsorbed by ion exchange and electrostatic interaction. In conclusion, MnHAP-10 has the potential to be applied as an effective adsorbent for the removal of Pb(II) and Cd(II) pollution.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Cadmio/análisis , Manganeso , Durapatita/química , Plomo , Adsorción , Contaminantes Químicos del Agua/análisis , Cinética , Concentración de Iones de Hidrógeno
8.
Environ Technol ; 44(19): 2924-2945, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35225746

RESUMEN

Lead and cadmium are toxic to human, animal, and plant health; they enhance oxidative stress indirectly while simultaneously acting through other toxicodynamic mechanisms. In this study, pristine vermiculite (VER) was functionalized with butylamine (BUT) and a novel organoclay (BUT-VER) adsorbent material was produced for simultaneous removal of Pb(II) and Cd(II) in aquatic medium. The adsorbents were characterized by spectroscopic, microscopic, spectrometric, and potentiometric techniques. The adsorption affecting parameters, including pH, time, initial concentration, temperature, and co-existing cations were investigated and optimized. The kinetic data results were in better agreement with pseudo-second-order (PSO) model (R2 > 0.992). Multiple isotherm models were used to study the adsorption system and results showed that adsorption was monolayer. The BUT-VER showed an improvement in adsorption capacity in a single system (Pb(II): from 134.2 to 160.6 mg g-1) and (Cd(II): from 51.1 to 58.9 mg g-1) while in binary system (Pb(II): from 107.3 to 114.5 mg g-1) and (Cd(II): from 33.7 to 39.7 mg g-1), respectively. Furthermore, BUT-VER was tested in real river water and removed efficiency of >99% was achieved in just 1 h. The dominant mechanisms were electrostatic attraction and complexation. BUT-VER was regenerated for five consecutive cycles and showed >90% removal efficiency. These findings suggest that the proposed inexpensive adsorbent has the potential for practical applications of toxic metals removal from water.


Asunto(s)
Cadmio , Contaminantes Químicos del Agua , Humanos , Cadmio/química , Butilaminas , Plomo/análisis , Adsorción , Ríos , Agua/química , Iones/química , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno
9.
J Hazard Mater ; 435: 128964, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35490632

RESUMEN

The ubiquitous Al2O3 is anticipated to interact with nanoplastics, affecting their fate and transport in aquatic environments. In this study, the heteroaggregation and deposition behaviors of polystyrene nanoplastics (PSNPs) on Al2O3 were systematically investigated under different conditions (ionic strength, pH, and natural organic matter). The results showed that significant heteroaggregation occurred between PSNPs and Al2O3 particles under acidic and neutral conditions. When the NaCl concentration was increased from 50 to 500 mM, the heteroaggregation ratio gradually increased. However, poly (acrylic acid) (PAA) inhibited the heteroaggregation of PSNPs-Al2O3 due to steric repulsion. The deposition of PSNPs on Al2O3 surfaces was inhibited as the NaCl concentration or pH values increased. Due to charge reversal and steric repulsion, humic acid (HA) and fulvic acid (FA) prevented the deposition of PSNPs onto Al2O3 surfaces, and the former was more effective in reducing the deposition rate. The interaction mechanism between PSNPs and Al2O3 was revealed by using various characterization techniques and density function theory (DFT) calculation. The results demonstrated that in addition to the dominant electrostatic interaction, there were also weak hydrogen bonds and van der Waals interactions. Our research is of great significance for predicting the migration and fate of PSNPs in aquatic environments.


Asunto(s)
Microplásticos , Cloruro de Sodio , Sustancias Húmicas , Concentración Osmolar , Poliestirenos/química
10.
Sci Total Environ ; 777: 146123, 2021 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-33684763

RESUMEN

The aluminum dross (AD), which causes numerous problems of its management and disposal to environment is a useful resource to extract alumina. This study explains a novel process to extract highly pure alumina (Al2O3) from AD at a high extraction rate without producing the residues and exhaust gases. An experimental set up was designed to perform the grinding of AD for the decomposition of aluminum nitride (AlN) and the removal of salts. Thereby, the desalted dross was used to detect the optimum alkaline (NaOH) calcination parameters and leaching conditions, as well as the dissolution kinetics of alumina and silica. The leaching residues were used to produce Ettringite mineral with calcium-based compounds (including CaO and CaSO4) to avoid the problems of solid waste disposal from the leaching process. Moreover, to purify the alumina, slightly soluble CaSO4 was added in leaching solution to precipitate silicate and the optimum additive/solution ratio (g/mL) was determined. The aluminum hydroxide (Al(OH)3), precipitated after the carbonization was calcinated at 900.0 °C for 2 h to produce γ-alumina. The morphological and mineralogical characterizations of AD, γ-Al2O3 and the synthesized Ettringite mineral were studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and X-ray fluorescence (XRF). It was observed that activation temperature of 1000.0 °C, Na2O/Al2O3 molar ratio of 1.4, leaching temperature of 60.0 °C, leaching time of 40.0 min, and the leaching liquid/solid ratio (mL/g) of 25/1 were the optimal parameter conditions to extract alumina with the extraction rate at 86.7% and purity of more than 98%. The results of leaching kinetics' study showed that the dissolution of alumina and silica were both controlled by layer diffusion process with the apparent activation energy of 11.4010 kJ·mol-1 and 2.0556 kJ·mol-1, respectively.

11.
Water Res ; 168: 115182, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31634706

RESUMEN

Low-molecular-weight organic acids (LMWOAs) are ubiquitous in the aquatic environment and consequently may affect the heavy metal transport in aquifer systems. In this study, the influences of LMWOAs on the transport of Cd2+ under different pH conditions in saturated porous media were evaluated. For this, three LMWOAs such as acetic acid, tartaric acid, and citric acid were employed. A two-site nonequilibrium transport model was applied to simulate the transport data. Under acidic conditions (pH 5.0), the results indicated that LMWOAs inhibited the transport of Cd2+ even at the low concentrations of organic acids (i.e., 0.05 and 0.1 mM). The inhibition effects might be attributed to the complexation role of the sand surface-bound organic acids and also electrostatic interaction. Meanwhile, the inhibition effects of LMWOAs on Cd2+ transport in the following order of citric acid > tartaric acid > acetic acid, which was also in agreement with the decreasing complex stability constants between Cd2+ and LMWOAs. This order may be dependent on their molecular structures (i.e., amount and type of functional groups) and complexing strength. Interestingly, when the LMWOA concentrations 0.5 mM, tartaric acid and citric acid still inhibited Cd2+ transport, while acetic acid slightly enhanced the Cd2+ mobility due to its weaker complexing strength. However, under neutral conditions (pH 7.0), LMWOAs generally enhanced the transport of Cd2+. The transport-enhancement of LMWOAs was ascribed to the formation of stable aqueous non-adsorbing Cd-organic acid complexes. In addition, citric acid could obviously inhibit the transport of Cd2+ under competitive transport conditions (i.e., with competing cations), which is mainly due to different complex affinities of citric acid to Pb2+ and Cd2+. These findings demonstrate that LMWOAs may inhibit or facilitate Cd2+ transport under different environmental conditions. Thus, environmental assessment concerning the transport of heavy metals should consider the roles of organic acids.


Asunto(s)
Contaminantes del Suelo , Cadmio , Peso Molecular , Porosidad , Suelo
12.
Environ Sci Process Impacts ; 21(7): 1153-1163, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31157350

RESUMEN

Tetracycline is one of the most commonly used antibiotics in the world. Eventually, large amounts of this contaminant will enter into the subsurface environment, where a variety of ions exist. In this study, the effects of divalent metal cations (Mg2+, Ca2+, Pb2+ and Cu2+) and inorganic anions (Cl-, NO3-, SO42- and H2PO4-) on the transport of tetracycline in saturated porous media were investigated. Both batch and column experiments were conducted to determine the interactions between tetracycline and sand. Batch sorption experimental results showed that the presence of divalent metal cations could increase the sorption of tetracycline onto sand due to the cation-bridging mechanism. When Na+ was the counterion in the background solution, anions caused a significant decrease in tetracycline sorption owing to the occupation of some adsorption sites by anions and the decrease of electrostatic attraction. Column experiments indicated that the inhibition effects of divalent cations followed the order of Cu2+ > Pb2+ > Ca2+ ≈ Mg2+; the regular pattern might be related to their different complexing strengths. The presence of inorganic anions enhanced the mobility of tetracycline following the order of H2PO4- > SO42- > NO3- > Cl-. Transport-enhancement effects of anions were ascribed to competition between inorganic anions and tetracycline for deposition sites on sand surfaces. However, when Ca2+ was the counterion, the differences in the breakthrough curve of tetracycline among three inorganic anions (i.e., SO42-, NO3- and Cl-) were very small. In this case, the transport-inhibiting effects of anions could be counterbalanced by the transport-enhancement effects of the cation-bridging effect. Also, the two-site nonequilibrium transport model was applied to analyze the transport data. Findings from this study improve our understanding of the transport of tetracycline in saturated aquifer materials.


Asunto(s)
Aniones/química , Cationes Bivalentes/química , Modelos Teóricos , Dióxido de Silicio/química , Tetraciclina/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Porosidad , Tetraciclina/química , Contaminantes Químicos del Agua/química
13.
Sci Total Environ ; 666: 94-102, 2019 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-30798247

RESUMEN

The impact of low-molecular weight organic acids (LMWOAs) on the transport of graphene oxide (GO) nanoparticles in saturated quartz sand was investigated. The different LMWOAs such as acetic acid, glycolic acid, malonic acid, and tartaric acid were used in experiments. The effects of LMWOAs on the transport of GO were markedly dependent upon organic acid species. In general, the transport enhancement effects followed the order of tartaric acid > malonic acid > glycolic acid > acetic acid, the regular pattern might be related to amount and type of functional groups of LMWOAs. Additionally, the different enhanced ability of LMWOAs was determined by their molecular weight. In the presence of Na+, the main deposition mechanism was ascribed to steric hindrance and competition between LMWOA and GO for deposition sites on grain surfaces under acidic conditions (i.e., pH 4.0 and 5.0). Batch adsorption experiments indicated the extents of competitive adsorption between LMWOAs and GO on quartz sand. In addition, the DLVO theory was not applicable to describe the transport of GO in the presence of LMWOAs at pH 5.0. Nevertheless, electrostatic and steric repulsion, existing between GO and sand grains, were the most important deposition mechanisms under the neutral condition (i.e., pH 7.0). When Ca2+ was the main cation in the background solution, the transport enhancement effects followed quite similar order to those of Na+, mainly due to different complexing strength of organic acids.

14.
Environ Sci Process Impacts ; 21(3): 506-513, 2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30681085

RESUMEN

With the increase in production and wide application of graphene oxide (GO), colloidal GO particles are expectantly released into soil and groundwater, where a large number of mineral particles exist. In addition, the porewater chemistry (e.g. organic acid, valence of cation) is a neglected but important aspect to comprehensively investigate the fate of GO. The interactions of GO with three ubiquitous clay minerals (i.e., montmorillonite, kaolinite and diatomite) have been systematically investigated through batch experiments across different solution chemistry conditions. In general, the affinity towards GO is in the order of montmorillonite > kaolinite > diatomite under the same experimental conditions. This observation can be explained by the characteristics of different clay minerals, such as surface charge and surface area. The results indicated that increasing the ionic strength or decreasing the pH enhanced the attachment of GO nanoparticles onto clay minerals as a result of electrostatic interactions. With the increase in concentration of Ca2+, more GO particles were attached onto clay mineral particles. This is caused by complexation between the surface oxygen functional groups of both GO nanoparticles and clay minerals. The presence of 0.1 mM tartaric acid significantly inhibited the attachment of GO onto clay minerals. This is possibly linked to the increased negative charges of the organic acids and the competition between organic acids and GO. The interaction energies were also calculated by applying the classical DLVO theory. The results of this study have helped to understand the behavior and fate of GO in subsurface formations.


Asunto(s)
Bentonita/química , Arcilla/química , Tierra de Diatomeas/química , Grafito/química , Caolín/química , Nanopartículas/química , Adsorción , Silicatos de Aluminio/química , Modelos Teóricos , Concentración Osmolar , Suelo/química , Solubilidad
15.
J Environ Manage ; 231: 391-396, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30368148

RESUMEN

A low-cost mercapto-modified coal gangue (CG-SH) was fabricated by modification of coal gangue (CG) with (3-mercaptopropyl) trimethoxysilane. The structure and composition for as-prepared CG-SH were characterized by using X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray fluorescence (XRF). Results indicated that larger amounts of mercapto-groups (-SH) was successfully introduced onto CG, which followed by acted as active sites for the removal of heavy metal cations, such as Pb(II), Cd(II) and Hg(II). The factors that affected the adsorption equilibrium as well as the removal efficiency, i.e., contact time, initial concentration, pH and temperature, were investigated in detail. The adsorption isotherms for Pb(II), Cd(II) and Hg(II) were well fitted with Langmuir model. The maximum adsorption capacity of CG-SH for Pb(II), Cd(II) and Hg(II) were calculated to be 332.8, 110.4 and 179.2 mg g-1, respectively. The adsorption for Pb(II), Cd(II) and Hg(II) on CG-SH could be well described by pseudo-second-order kinetic model. And thermodynamic analysis suggests that the adsorption process for Pb(II) is exothermal, while that for Cd(II) and Hg(II) are endothermal. The results suggest CG-SH have great potential to be used as efficient absorbent for the removal of heavy metal cations from water.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Adsorción , Cadmio , Carbón Mineral , Concentración de Iones de Hidrógeno , Cinética , Plomo
16.
Infect Dis (Lond) ; 48(3): 222-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26542751

RESUMEN

OBJECTIVE: The role of the cytokine, macrophage migration inhibition factor (MIF) was assessed in tuberculosis. This case-control study investigated whether commonly occurring functional MIF polymorphisms are associated with active tuberculosis as well as with serum levels of MIF, IFN-γ and TNF-α. METHODS: Two MIF promoter polymorphisms, a functional -794 CATT5-8 microsatellite repeat (rs5844572) and a -173G/C single-nucleotide polymorphism (rs755622), were analysed by PCR and PCR-RFLP, respectively, in 47 patients and 50 healthy subjects. The mRNA level of MIF was performed by real-time PCR (RT-PCR), and MIF, IFN-γ and TNF-α serum levels were determined by ELISA. RESULTS: A significant increase of MIF mRNA expression and MIF protein level were found in patients compared to healthy controls. Meanwhile, the increase of IFN-γ and TNF-α serum levels were confirmed. According to the profile of genetic model, a significant association was found of genotypes carrying the -794 CATT 7 or 8 and -173 C risk alleles with susceptibility to active tuberculosis and with a significant increase of MIF, IFN-γ and TNF-α. CONCLUSIONS: These data suggested a distinct genetic and immunopathogenic basis for tuberculosis at the MIF locus. Serum MIF, IFN-γ and TNF-α profiles distinguish tuberculosis from the more inflammatory phenotype and may play a role in pathogenesis and as biomarkers of active tuberculosis.


Asunto(s)
Interferón gamma/sangre , Oxidorreductasas Intramoleculares/genética , Factores Inhibidores de la Migración de Macrófagos/genética , Tuberculosis Pulmonar/genética , Adulto , Estudios de Casos y Controles , China , Femenino , Humanos , Oxidorreductasas Intramoleculares/sangre , Factores Inhibidores de la Migración de Macrófagos/sangre , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Tuberculosis Pulmonar/sangre , Factor de Necrosis Tumoral alfa/sangre
17.
Clinics (Sao Paulo) ; 70(7): 524-30, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26222823

RESUMEN

Recently, a series of studies explored the correlation between the neutrophil to lymphocyte ratio and the prognosis of lung cancer. However, the current opinion regarding the prognostic role of the neutrophil to lymphocyte ratio in lung cancer is inconsistent. We performed a meta-analysis of published articles to investigate the prognostic value of the neutrophil to lymphocyte ratio in lung cancer. The hazard ratio (HR) and its 95% confidence interval (CI) were calculated. An elevated neutrophil to lymphocyte ratio predicted worse overall survival, with a pooled HR of 1.243 (95%CI: 1.106-1.397; P(heterogeneity)=0.001) from multivariate studies and 1.867 (95%CI: 1.487-2.344; P(heterogeneity)=0.047) from univariate studies. Subgroup analysis showed that a high neutrophil to lymphocyte ratio yielded worse overall survival in non-small cell lung cancer (NSCLC) (HR=1.192, 95%CI: 1.061-1.399; P(heterogeneity)=0.003) as well as small cell lung cancer (SCLC) (HR=1.550, 95% CI: 1.156-2.077; P(heterogeneity)=0.625) in multivariate studies. The synthesized evidence from this meta-analysis of published articles demonstrated that an elevated neutrophil to lymphocyte ratio was a predictor of poor overall survival in patients with lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Linfocitos/patología , Neutrófilos/patología , Carcinoma Pulmonar de Células Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Humanos , Neoplasias Pulmonares/mortalidad , Recuento de Linfocitos , Pronóstico , Carcinoma Pulmonar de Células Pequeñas/mortalidad
18.
Clinics ; 70(7): 524-530, 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-752390

RESUMEN

Recently, a series of studies explored the correlation between the neutrophil to lymphocyte ratio and the prognosis of lung cancer. However, the current opinion regarding the prognostic role of the neutrophil to lymphocyte ratio in lung cancer is inconsistent. We performed a meta-analysis of published articles to investigate the prognostic value of the neutrophil to lymphocyte ratio in lung cancer. The hazard ratio (HR) and its 95% confidence interval (CI) were calculated. An elevated neutrophil to lymphocyte ratio predicted worse overall survival, with a pooled HR of 1.243 (95%CI: 1.106-1.397; Pheterogeneity=0.001) from multivariate studies and 1.867 (95%CI: 1.487-2.344; Pheterogeneity=0.047) from univariate studies. Subgroup analysis showed that a high neutrophil to lymphocyte ratio yielded worse overall survival in non-small cell lung cancer (NSCLC) (HR=1.192, 95%CI: 1.061-1.399; Pheterogeneity=0.003) as well as small cell lung cancer (SCLC) (HR=1.550, 95% CI: 1.156-2.077; Pheterogeneity=0.625) in multivariate studies. The synthesized evidence from this meta-analysis of published articles demonstrated that an elevated neutrophil to lymphocyte ratio was a predictor of poor overall survival in patients with lung cancer. .


Asunto(s)
Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Linfocitos/patología , Neutrófilos/patología , Carcinoma Pulmonar de Células Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Recuento de Linfocitos , Neoplasias Pulmonares/mortalidad , Pronóstico , Carcinoma Pulmonar de Células Pequeñas/mortalidad
19.
Wei Sheng Wu Xue Bao ; 51(4): 458-67, 2011 Apr.
Artículo en Chino | MEDLINE | ID: mdl-21796979

RESUMEN

OBJECTIVE: To investigate co-existence of resistance genes (beta-lactamases, BLs, and aminoglycoside-modifying enzymes, AMEs) and their association with the genetic marker genes of Class I, II, III integrons carried by multiresistant Escherichia coli isolates. METHODS: We used VITEK-GNS to determine the susceptibility of 136 isolates to 14 antibiotics, disc agar diffusion test to confirm ESBL-producing isolates, PCR to analyze BLs, AMEs and integrons genes, conjugation and plasmids extraction to locate the methylase genes. RESULTS: We found that 70.59% of the isolates produced ESBLs. They showed stronger resistance against 9 antibiotics than isolates without ESBLs in 14 antibiotics. PCR amplification showed that the positive rate of BLs, AMEs and qacEdelta1-sul1 was 96.32% , 100% and 94.12%, respectively, but Class II, III integrons genes were negative. Only one strain was oprD2 gene negative. 90.44% of the isolates were both positive for BLs and qacEdelta1-sul1 genes, and 94.12% for AMEs and qacEdelta1-sul1 genes, but there was no statistical significance. 90.44% of the isolates were all positive for the 3 genes. 12 strains carried 16S rRNA methylase genes including armA (2.21%), rmtB (7.35%) while rmtA, rmtC, rmtD were negative. The conjugation assay and plasmids mapping results showed that the methylase genes were located on the 23 kb plasmid, and the efficiency of transformation was 83.3%. CONCLUSIONS: The results suggested that there was a tight correlation between the 3 genes (BLs, AMEs and qacEdelta1-sul1) and the incidences of multi-resistance of Escherichia coli, but there was no correlation of the incidence of multi-resistance with Class II, III integrons. 16S rRNA methylase genes harboured plasmids of -23 kb which transformed other isolates within the same strains efficiently.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Integrones , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
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