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1.
J Hazard Mater ; 423(Pt B): 127164, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34534803

RESUMO

Non-ferrous metal(loid)s in region with karst characteristic are highly diffusible, especially by runoff or atmospheric deposition. However, microbiota in response to the diffusing metal(loid)s is still to be understood. In this study, we focused on microbiota across metal(loid)s diffusion pathways around a non-ferrous smelting assembly. The microbial distribution and metal(loid)s-microbial interactions were analysed by 16S rRNA amplicon and multivariate statistical analysis. Although runoff and atmospheric deposition showed similar metal(loid)s diffusion contribution, different microbial compositions were revealed. The microbiota along the runoff transect (region3) was similar to those within the atmospheric deposition transect (region4), which significantly differed from those closer to the smelting assembly (region1 and region2; R2 = 0.3866, p = 0.001). Random forest model indicated the negative impacts of bioavailable metal(loid)s on microbial diversity. Proteobacteria was predominant in region1 while Actinobacteriota dominated in the other regions. Twenty abundant genera were identified in metal(loid)s rich area, such as sulfur metabolizer Sulfurifustis and metal resistant Acinetobacter. Interactions between the geochemical parameters and the dominant taxa indicated that the main drivers were Al, Sb, As and their bioavailable fractions and sulfate. This study provides understandings of microbiota patterns towards different metal(loid)s diffusion pathways around non-ferrous smelting assembly with karst characteristic.


Assuntos
Metaloides , Metais Pesados , Microbiota , Poluentes do Solo , Bactérias/genética , China , Monitoramento Ambiental , Metaloides/análise , Metais/análise , Metais Pesados/análise , RNA Ribossômico 16S/genética , Poluentes do Solo/análise
2.
Chemosphere ; 287(Pt 1): 131970, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34450370

RESUMO

In this study, a polydopamine (PDA) modified attapulgite (ATP) supported nano sized zero-valent iron (nZVI) composite (PDA/ATP-nZVI) was rapidly synthesized under acidic conditions, and employed to alleviate Cr(VI) toxicity from an aqueous solution. Kinetic studies revealed that Cr(VI) adsorption process followed the pseudo-second order model, suggesting chemisorption was the dominant adsorption mechanism. Liu isotherm adsorption model was able to better describe the Cr(VI) adsorption isotherm with the maximum adsorption capacity of 134.05 mg/g. The thermodynamic study demonstrated that the adsorption process occurred spontaneously, accompanied by the increase in entropy and endothermic reaction. Low concentrations of coexisting ions had negligible effects on the removal of Cr(VI), while high concentrations of interfering ions were able to facilitate the removal of Cr(VI). Reactive species test revealed that Fe2+ played a key role in Cr(VI) reduction by PDA/ATP-nZVI. PDA enhanced the elimination of Cr(VI) via donation of electrons to Cr(VI) and acceleration of Fe3+ transformation to Fe2+. Furthermore, PDA was able to effectively inhibit the leaching of iron species and generation of ferric hydroxide sludge. Mechanistic study revealed that 72% of Cr(VI) elimination was attributed to reduction/precipitation, while 28% of Cr(VI) elimination was due to the surface adsorption.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Cromo , Indóis , Cinética , Compostos de Magnésio , Polímeros , Compostos de Silício , Poluentes Químicos da Água/análise
3.
Chemosphere ; 282: 130992, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34087556

RESUMO

Mining and smelting activities have introduced severe potentially toxic metals (PTMs) contamination into surrounding soil settings. Influences of PTMs on microbial diversity have been widely studied. However, variations of microbial communities, network structures and community functions in different levels of PTMs contaminated soils adjacent to mining and smelting aera are still poorly investigated. In this study, microbial communities of soils around different levels of PTMs contamination were comprehensively studied by 16S rRNA gene amplicons high-throughput sequencing. Microbial interactions and module functions were also exploited to ascertain the discrepancies of PTMs concentration levels on microbial ecological functions. Results indicated that the microbial community composition was significantly distinct attributed to the phylum Protebacteria (p = 0.002) dominating in soil with high level PTMs contents but Actinobacteria (p = 0.002) in low level of PTMs-contaminated soil. Microbial α diversity was not significantly influenced by different levels of PTMs contaminations. Microorganisms proactively responded to PTMs content levels by means of strengthening network complexities and modularities among microbe-microbe interactions. The functions of main network modules were predicted associating membrane transport, amino acid metabolism, energy metabolism and carbohydrate metabolism. The PTMs detoxification and anti-oxidation were significantly strengthened at the high level of PTMs contamination. The present study demonstrated that modification of microbial community by the adaptive adjustment of microbial compositions and strengthening their network complexity and modularity.


Assuntos
Metais Pesados , Microbiota , Poluentes do Solo , Metais Pesados/análise , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
4.
Chemosphere ; 275: 130080, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33667764

RESUMO

For the first time, high energy VUV photons and generation of O3 by (V)UV lamps were applied together for removal of active pharmaceutical ingredients (APIs) from biologically treated wastewater (BTWW) in pilot-scale. The core of the pilot container unit was a photoreactor assembly consisting of six photoreactors, each containing a low-pressure Hg lamp (UV dose of 1.2 J/cm2 and 6.6 J/cm2 at 185 nm and 254 nm, respectively). BTWW was irradiated (4.75 min residence time) by (V)UV light in presence of in situ photochemically generated O3 from coolant air of the lamps. Experiments were conducted at the site of two wastewater treatment plants. Out of seven target APIs (namely carbamazepine, ciprofloxacin, clarithromycin, diclofenac, metoprolol, sitagliptin, and sulfamethoxazole), 80-100% removal was accomplished for five and 40-80% for two compounds. Two degradation products of carbamazepine were detected. Degradation products of other target compounds were not found. The applied O3 dose was 30-45 µg O3/mg dissolved organic carbon. Inactivation of up to log-4.8, log-4.5 and log-3.8 could be achieved for total coliform, Escherichia coli and Enterococcus faecalis, respectively. SOS Chromotest indicated no genotoxicity nor acute toxicity. Generation of neither NH4+, NO2- nor NO3- was observed during post-treatment. Electric energy per order values were calculated for the first time for (V)UV/O3 treatment in BTWW with a median value of 1.5 kWh/m3. This technology can be proposed for post-treatment of BTWWs of small settlements or livestock farms to degrade micropollutants before water discharge or for production of irrigation water. Further studies are essential in pilot-scale for other applications.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Oxirredução , Tecnologia , Raios Ultravioleta , Águas Residuárias , Poluentes Químicos da Água/análise
5.
Environ Pollut ; 273: 115667, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33497944

RESUMO

Mine tailings sites are considered as a continuous source of discharged metal(loid)s and residual organic flotation reagents. They are extremely toxic environments representing unique ecological niches for microbial communities. Mine tailings as a source of multi-resistance genes have been poorly investigated. Metagenomic analysis for four active nonferrous metal(loid) tailings sites with different environmental parameters was conducted. The abundance of Thiobacillus, able to tolerate acidity and showing iron- and sulfur/sulfide oxidation capacities, was significantly different (p < 0.05) between acid and neutral tailings sites. Correlation analyses showed that Zn, Pb, TP, Cd, and Cu were the main drivers influencing the bacterial compositions. Multi-metal resistance genes (MRGs) and antibiotic resistance genes (ARGs), such as baca and copA, were found to be co-selected by high concentrations of metal(loid)s tailings. The main contributors to different distributions of MRGs were Thiobacillus and Nocardioides genus, while genera with low abundance (<0.1%) were the main contributors for ARGs. Functional metabolic pathways related to Fe-S metabolism, polycyclic aromatic hydrocarbons (PAHs) degradation and acid stress were largely from Altererythrobacter, Lysobacter, and Thiobacillus, respectively. Such information provides new insights on active tailings with highly toxic contaminants. Short-term metal(loid) exposure of microorganism in active nonferrous metal(loid) tailings contribute to the co-occurrence of ARGs and MRGs, and aggravation of tailings acidification. Our results recommend that the management of microorganisms involved in acid tolerance and metal/antibiotic resistance is of key importance for in-suit treatment of the continuous discharge of tailings with multiple metal(loid) contaminants into impoundments.

6.
Indoor Air ; 30(1): 76-87, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593610

RESUMO

The aim of this study was to identify determinants of aldehyde and volatile organic compound (VOC) indoor air concentrations in a sample of more than 140 office rooms, in the framework of the European OFFICAIR research project. A large field campaign was performed, which included (a) the air sampling of aldehydes and VOCs in 37 newly built or recently retrofitted office buildings across 8 European countries in summer and winter and (b) the collection of information on building and offices' characteristics using checklists. Linear mixed models for repeated measurements were applied to identify the main factors affecting the measured concentrations of selected indoor air pollutants (IAPs). Several associations between aldehydes and VOCs concentrations and buildings' structural characteristic or occupants' activity patterns were identified. The aldehyde and VOC determinants in office buildings include building and furnishing materials, indoor climate characteristics (room temperature and relative humidity), the use of consumer products (eg, cleaning and personal care products, office equipment), as well as the presence of outdoor sources in the proximity of the buildings (ie, vehicular traffic). Results also showed that determinants of indoor air concentrations varied considerably among different type of pollutants.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Local de Trabalho/estatística & dados numéricos , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Aldeídos/análise , Europa (Continente) , Modelos Lineares , Compostos Orgânicos Voláteis/análise
7.
Ecotoxicol Environ Saf ; 186: 109773, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31614300

RESUMO

Understanding the mechanism(s) of microbial resistance to antimony (Sb) is critical in the bioremediation of Sb polluted environments. Here a novel bacterium (Acinetobacter sp. JH7) isolated from mine tailings decreased the Microtox toxicity of a Sb(III)-containing medium. DNA sequencing and physiological testing were employed for the identification and characterization of strain JH7. Following a batch experiment, Fourier transform infrared spectroscopy (FTIR) and antimony speciation analyses determined the adsorption and oxidation of antimony. Analyses of Sb(III) distribution revealed that extracellular polymeric substances and cell walls inhibited Sb(III) entry into JH7 cells. FTIR studies indicated that key functional groups including -OH, C-N, and C-O likely participated in Sb(III) biosorption. Isothermal and kinetic studies revealed that Sb(III) sorption to viable JH7 cells fitted the Langmuir model (R2 = 0.99) and could be described by pseudo-second order kinetics (R2 = 0.99). Furthermore, the increase of anti-oxidative enzymatic activity of JH7 enhanced the intracellular detoxification of Sb(III), which would indirectly contribute to the Sb(III) resistance ability of strain JH7. Our results indicate that biosorption and ROS oxidation of Sb(III) were likely responsible for the decreased toxicity of Sb. The greater understanding how Acinetobacter sp. JH7 lowers the environmental Sb(III) toxicity could provide a basis for future research and subsequent development of technologies for the remediation of Sb contaminated sites.


Assuntos
Acinetobacter/efeitos dos fármacos , Antimônio/análise , Farmacorresistência Bacteriana , Poluentes Ambientais/análise , Mineração , Acinetobacter/isolamento & purificação , Adsorção , Antimônio/toxicidade , Biodegradação Ambiental , China , Poluentes Ambientais/toxicidade , Cinética , Oxirredução
8.
Environ Pollut ; 255(Pt 2): 113165, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546074

RESUMO

Nonferrous mine tailings have caused serious problems of co-contamination with metal(loid)s. It is still a global challenge to cost-effectively manage and mitigate the effect of the mining wastes. We conducted an in-situ bio-treatment of non-ferrous metal(loid) tailings using a microbial consortium of sulfate reducing bacteria (SRB). During the bio-treatment, the transformation of metal(loid)s (such as Cu, Fe, Mn, Pb, Sb, and Zn) into oxidizable and residual fractions in the subsurface tended to be higher than that observed in the surface. As well the mineral compositions changed becoming more complex, indicating that the sulfur reducing process of bio-treatment shaped the bio-transformation of metal(loid)s. The added SRB genera, especially Desulfotomaculum genus, colonized the tailings suggesting the coalescence of SRB consortia with indigenous communities of tailings. Such observation provides new insights for understanding the functional microbial community coalescence applied to bio-treatment. PICRUSt analysis revealed presence of genes involved in sulfate reduction, both assimilatory and dissimilatory. The potential for the utilization of both inorganic and organic sulfur compounds as S source, as well as the presence of sulfite oxidation genes indicated that SRB play an important role in the transformation of metal(loid)s. We advocate that the management of microorganisms involved in S-cycle is of paramount importance for the in situ bio-treatment of tailings, which provide new insights for the implementation of bio-treatments for mitigating the effect of tailings.


Assuntos
Biodegradação Ambiental , Metais/metabolismo , Bactérias/genética , Metais/análise , Consórcios Microbianos , Microbiota , Minerais , Mineração , Oxirredução
9.
Chemosphere ; 226: 659-667, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30959450

RESUMO

The combined contamination of nonferrous metal(loid) mining and smelting areas is a global issue, in need of urgent management. To our knowledge, this is the first report of microbial activities by microcalorimetry in specific nonferrous metal(loid) tailings with oligonutrition and high contents of toxic metal(loid)s. Dynamics of bacterial diversity were also characterized. Here we show that tailings had low microbial activities (Pmax = 64.1-331 µW g-1), which were accelerated by the presence of dipotassium phosphate (Pmax = 346-856 µW g-1), as measured by microcalorimetry. Frequent detection of S- and metal-resistant related genera and differences of Thiobacillus and Acidithiobacillus abundances indicated that the tailings were in an early stage of acidification. It has been further confirmed by the presence of a weak acid environment and secondary sulfur associated minerals, such as Sb2S3, FeAsS, FeS2, and CuFeS2. During the acidification process, phosphate, metal(loid)s, and microbial activity were correlated to the bacterial communities. It is suggested that the bacterial communities have metabolic capacities with a high potential for the use in management processes of multi-contaminated nonferrous metalliferous tailings.


Assuntos
Metais/química , Minerais/química , Mineração/métodos
10.
J Trace Elem Med Biol ; 47: 79-88, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29544811

RESUMO

In the present study, several Cu chelators [2,2'-biquinoline, 8-hydroxiquinoline (oxine), ammonium pyrrolidinedithiocarbamate (APDTC), Dp44mT, dithizone, neocuproine] were used to study Cu uptake, depletion and localization in different cancer cell lines. To better understand the concentration dependent fluctuations in the Cu intracellular metal content and Cu-dependent in vitro antiproliferative data, the conditional stability constants of the Cu complex species of the investigated ligands were calculated. Each investigated chelator increased the intracellular Cu content on HT-29 cells causing Cu accumulation depending on the amount of the free Cu(II). Copper accumulation was 159 times higher for Dp44mT compared to the control. Investigating a number of other transition metals, intracellular accumulation of Cd was observed only for two chelators. Intracellular Zn content slightly decreased (cca. 10%) for MCF-7 cells, while a dramatic decrease was observed on MDA-MB-231 ones (cca. 50%). A similar decrease was observed for HCT-116, while Zn depletion for HT-29 corresponded to cca. 20%. The IC50 values were registered for the investigated four cell lines at increasing external Cu(II) concentration, namely, MDA-MB-231 cells had the lowest IC50 values for Dp44mT ranging between 7 and 35 nM. Thus, Zn depletion could be associated with lower IC50 values. Copper depletion was observed for all ligands being less pronounced for Dp44mT and neocuproine. Copper localization and its colocalization with Zn were determined by µ-XRF imaging. Loose correlation (0.57) was observed for the MCF-7 cells independently of the applied chelator. Similarly, a weak correlation (0.47) was observed for HT-29 cells treated with Cu(II) and oxine. Colocalization of Cu and Zn in the nucleus of HT-29 cells was observed for Dp44mT (correlation coefficient of 0.85).


Assuntos
Quelantes/farmacologia , Cobre/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cobre/farmacocinética , Cobre/toxicidade , Ditizona/farmacologia , Humanos , Metais/farmacocinética , Oxiquinolina/farmacologia , Fenantrolinas/farmacologia , Tiossemicarbazonas/farmacologia , Zinco/metabolismo , Zinco/farmacocinética
11.
Environ Sci Pollut Res Int ; 25(3): 2021-2034, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27761869

RESUMO

The bulk analysis of single feathers of 263 feathers belonging to 238 individuals of a migratory passerine (collared flycatcher, Ficedula albicollis, originating from a breeding population in the Pilis-Visegrád Mountains in Hungary) by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS) for determination of elements after proper dissolution allowed the quantitative determination of 38 elements. Calcium, Mg, Mn, Fe, and Zn were found to have a quantitative determination frequency larger than 80 % and a concentration greater than 100 µg/g. Among ecotoxicologically relevant elements, Ni, Cd, Hg, and Pb could be determined in more than 55 % of the tail feather samples. The concentration of Hg with a quantification limit of 0.006 µg/g and Pb with that of 0.015 µg/g was higher than 1 and 10 µg/g, respectively, in more than 80 % of the investigated samples, but generally lower than levels that could cause adverse behavioral effects. The principal component analyses of elemental concentration data followed by the application of general linear models revealed that, for male collared flycatchers, the concentration of Sn, Pb, Ni, Sr, Mg, Zn, Ba, and Sc differed significantly in the wing and tail feathers collected from the same individuals. With females, only the Ca and Sc concentration showed a significant difference between wing and tail feathers. Moreover, the concentration of rare earth elements, V, Fe, Sr, Mg, Mn, Zn, Pb, and Ba in tail feathers allowed differentiation between sexes while the concentration of Se, Bi, and Sc between yearling and adult male individuals. At the same time, Sc differentiated age categories in females. Distribution of major elements along the rachis of feathers could be monitored by laser ablation ICP-SF-MS after normalization of the intensities to either 13C or 34S signals.


Assuntos
Plumas/química , Aves Canoras/metabolismo , Fatores Etários , Animais , Feminino , Hungria , Masculino , Muda , Análise de Componente Principal , Fatores Sexuais , Oligoelementos/análise
12.
Sci Total Environ ; 579: 169-178, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27866741

RESUMO

The European project OFFICAIR aimed to broaden the existing knowledge regarding indoor air quality (IAQ) in modern office buildings, i.e., recently built or refurbished buildings. Thirty-seven office buildings participated in the summer campaign (2012), and thirty-five participated in the winter campaign (2012-2013). Four rooms were investigated per building. The target pollutants were twelve volatile organic compounds, seven aldehydes, ozone, nitrogen dioxide and particulate matter with aerodynamic diameter <2.5µm (PM2.5). Compared to other studies in office buildings, the benzene, toluene, ethylbenzene, and xylene concentrations were lower in OFFICAIR buildings, while the α-pinene and d-limonene concentrations were higher, and the aldehyde, nitrogen dioxide and PM2.5 concentrations were of the same order of magnitude. When comparing summer and winter, significantly higher concentrations were measured in summer for formaldehyde and ozone, and in winter for benzene, α-pinene, d-limonene, and nitrogen dioxide. The terpene and 2-ethylhexanol concentrations showed heterogeneity within buildings regardless of the season. Considering the average of the summer and winter concentrations, the acetaldehyde and hexanal concentrations tended to increase by 4-5% on average with every floor level increase, and the nitrogen dioxide concentration tended to decrease by 3% on average with every floor level increase. A preliminary evaluation of IAQ in terms of potential irritative and respiratory health effects was performed. The 5-day median and maximum indoor air concentrations of formaldehyde and ozone did not exceed their respective WHO air quality guidelines, and those of acrolein, α-pinene, and d-limonene were lower than their estimated thresholds for irritative and respiratory effects. PM2.5 indoor concentrations were higher than the 24-h and annual WHO ambient air quality guidelines.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Europa (Continente) , Material Particulado/análise , Compostos Orgânicos Voláteis/análise
13.
Artigo em Inglês | MEDLINE | ID: mdl-27120608

RESUMO

Indoor environmental conditions (thermal, noise, light, and indoor air quality) may affect workers' comfort, and consequently their health and well-being, as well as their productivity. This study aimed to assess the relations between perceived indoor environment and occupants' comfort, and to examine the modifying effects of both personal and building characteristics. Within the framework of the European project OFFICAIR, a questionnaire survey was administered to 7441 workers in 167 "modern" office buildings in eight European countries (Finland, France, Greece, Hungary, Italy, The Netherlands, Portugal, and Spain). Occupants assessed indoor environmental quality (IEQ) using both crude IEQ items (satisfaction with thermal comfort, noise, light, and indoor air quality), and detailed items related to indoor environmental parameters (e.g., too hot/cold temperature, humid/dry air, noise inside/outside, natural/artificial light, odor) of their office environment. Ordinal logistic regression analyses were performed to assess the relations between perceived IEQ and occupants' comfort. The highest association with occupants' overall comfort was found for "noise", followed by "air quality", "light" and "thermal" satisfaction. Analysis of detailed parameters revealed that "noise inside the buildings" was highly associated with occupants' overall comfort. "Layout of the offices" was the next parameter highly associated with overall comfort. The relations between IEQ and comfort differed by personal characteristics (gender, age, and the Effort Reward Imbalance index), and building characteristics (office type and building's location). Workplace design should take into account both occupant and the building characteristics in order to provide healthier and more comfortable conditions to their occupants.


Assuntos
Ambiente Controlado , Local de Trabalho/psicologia , Adulto , Poluição do Ar em Ambientes Fechados , Eficiência , Emoções , Meio Ambiente , Etnicidade , Europa (Continente) , Feminino , Finlândia , França , Grécia , Humanos , Hungria , Itália , Masculino , Pessoa de Meia-Idade , Países Baixos , Percepção , Satisfação Pessoal , Portugal , Espanha , Inquéritos e Questionários , Local de Trabalho/estatística & dados numéricos
14.
J Biol Inorg Chem ; 21(2): 241-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26759251

RESUMO

Fast- and slow-proliferating human adenocarcinoma colorectal cells, HT-29 and HCA-7, respectively, overloaded with transferrin (Tf), Fe(III) citrate, Fe(III) chloride and Fe(II) sulfate were studied by synchrotron radiation total-reflection X-ray spectrometry (TXRF), TXRF-X-ray absorption near edge structure (TXRF-XANES), and micro-X-ray fluorescence imaging to obtain information on the intracellular storage of overloaded iron (Fe). The determined TfR1 mRNA expression for the investigated cells correlated with their proliferation rate. In all cases, the Fe XANES of cells overloaded with inorganic Fe was found to be similar to that of deliquescent Fe(III) sulfate characterized by a distorted octahedral geometry. A fitting model using a linear combination of the XANES of Tf and deliquescent Fe(III) sulfate allowed to explain the near edge structure recorded for HT-29 cells indicating that cellular overload with inorganic Fe results in a non-ferritin-like fast Fe storage. Hierarchical cluster analysis of XANES spectra recorded for Fe overloaded HT-29 and HCA-7 cells was able to distinguish between Fe treatments performed with different Fe species with a 95% hit rate, indicating clear differences in the Fe storage system. Micro-X-ray fluorescence imaging of Fe overloaded HT-29 cells revealed that Fe is primarily located in the cytosol of the cells. By characterizing the cellular Fe uptake, Fe/S content ratios were calculated based on the X-ray fluorescence signals of the analytes. These Fe/S ratios were dramatically lower for HCA-7 treated with organic Fe(III) treatments suggesting dissimilarities from the Tf-like Fe uptake.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Colo/metabolismo , Sobrecarga de Ferro/metabolismo , Síncrotrons , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Humanos
15.
Anal Chim Acta ; 819: 108-15, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24636418

RESUMO

A high performance liquid chromatography (HPLC) tandem mass spectrometric (MS/MS) method has been developed for the simultaneous determination of fifteen glucose, or acetate derived metabolites isolated from tumor cells. Glycolytic and tricarboxylic acid (TCA) cycle metabolites as well as acidic amino acids were separated on a HPLC porous graphitic carbon (PGC) column and simultaneously determined by means of triple quadrupole MS/MS using multiple reaction monitoring (MRM). Target compounds were eluted within 10 min with 8% v/v formic acid as an electronic modifier added to a 4:1 v/v methanol water mobile phase. The calibration is linear in the 1-100 µM concentration range for each analyte. The limit of detection ranges between 0.39 and 2.78 µM for the analytes concerned. To test the PGC-HPLC-MS/MS method in metabolomic studies, ZR-75.1 human mammary adenocarcinoma cells were labeled with U-(13)C glucose or 1-(13)C acetate. Applying the MRM mode, the incorporation of (13)C into metabolites, isolated from the tumor cells, and derived from glucose or acetate, could be properly identified.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias da Mama/metabolismo , Carbono/química , Metabolismo Energético , Adenocarcinoma/patologia , Neoplasias da Mama/patologia , Cromatografia Líquida , Humanos , Tamanho da Partícula , Porosidade , Espectrometria de Massas por Ionização por Electrospray , Propriedades de Superfície , Células Tumorais Cultivadas
16.
J Inorg Biochem ; 130: 52-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24176919

RESUMO

Di-2-pyridylketone-4,4,-dimethyl-3-thiosemicarbazone (Dp44mT) is a potential candidate in chelation therapy as an iron chelator. This study showed that a combined treatment with 2µM easily available Fe(II), Cu(II) and Zn(II) each and 5µM Dp44mT on eight different cancer cell lines resulted in a 10-40-fold increase in the intracellular Cu content compared to control samples. The uptake of Cu and Cu-dependent cytotoxicity strictly depend on the Cu concentration of the culture medium. Even as low concentration of Dp44mT as 0.1µM can transport high amounts of copper inside the cells. The Cu accumulation and toxicity through Dp44mT can hardly be influenced by Fe. Copper uptake and toxicity triggered by 2µM extracellular Cu(II) and 5µM Dp44mT could not be influenced by Fe(II) extracellular concentrations even 50-times higher than that of Cu(II). A 50-times higher Co(II) extracellular concentration hindered the Cu(II) uptake almost completely and a 10-times higher Co(II) concentration already decreased the Dp44mT-mediated Cu toxicity. Conditional complex stability constant determinations for Dp44mT with Cu(II), Co(II), Fe(II), Ni(II) and Zn(II) revealed that the metal-to-ligand ratio is 1:1 in [Cu(II)Dp44mT] complex, while for Co(II), Fe(II) and Ni(II) is 1:2. The highest stability constant was obtained for Cu(II) (lg ß=7.08±0.05) and Co(II) (lg ß2=12.47±0.07). According to our results, Dp44mT in combination with Cu is highly toxic in vitro. Therefore, the use of Dp44mT as an iron chelator is limited if biologically available Cu is also present even at low concentrations.


Assuntos
Quelantes/química , Quelantes/toxicidade , Tiossemicarbazonas/química , Tiossemicarbazonas/toxicidade , Linhagem Celular Tumoral , Cobalto/química , Cobalto/metabolismo , Cobre/metabolismo , Cobre/farmacocinética , Relação Dose-Resposta a Droga , Células HT29/efeitos dos fármacos , Células HT29/metabolismo , Humanos , Ferro/metabolismo , Quelantes de Ferro/química , Quelantes de Ferro/toxicidade , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Prótons , Tiossemicarbazonas/metabolismo , Tiossemicarbazonas/farmacocinética , Zinco/química , Zinco/metabolismo
17.
J Pharm Biomed Anal ; 90: 58-63, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24333705

RESUMO

Liquid chromatography quadrupole time-of-flight spectrometry (LC-Q-TOF-MS), equipped with electrospray ionization (ESI), was developed for the determination of the main metabolites of dipyrone - 4-aminoantipyrine (4-AA), 4-acetylaminoantipyrine (4-AAA), 4-formylaminoantipyrine (4-FAA) and 4-methylaminoantipyrine (4-MAA) in communal wastewater after reversed-phase solid phase extraction (SPE) in the low to several µg/l concentration range. Samples originated from conventional wastewater treatment plant (WWTP) using activated sewage sludge as well as from a pilot-scale WWTP operating in mixed mode (activated sewage sludge and cascade biofilms reactors with biofilms growing on fix beds and roots of greenhouse plants). Results of the present study confirmed the outcomes of our previous report according to which, 4-FAA was the most persistent metabolite, while 4-AAA and 4-MAA could be determined in the highest and lowest concentration, respectively. Moreover, the study of intraday variation of the concentration of these metabolites revealed that the concentration of 4-AA, 4-AAA and 4-FAA registered a 46%-75% increase in the samples collected at noon compared to those collected at 6 AM. Chlorination did not affect considerably the removal efficiency (about 15%) of these metabolites in samples collected for 3 months consecutively before and after disinfection. Both wastewater treatment techniques efficiently removed 4-AAA (between 80 and 96%). However, in the summer season, the removal efficiency of conventional WWTP using open-air aerated tanks is lower by 30%, (on average) than in the cold season. The concentration of the investigated metabolites showed increased concentrations in the winter season confirming the intake habits of the population from this popular analgesic and antipyretic drug.


Assuntos
Cromatografia Líquida/métodos , Dipirona/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Águas Residuárias/análise , Analgésicos/análise , Analgésicos/metabolismo , Biofilmes , Reatores Biológicos , Dipirona/metabolismo , Projetos Piloto , Estações do Ano , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
18.
Food Chem Toxicol ; 62: 601-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24075917

RESUMO

As part of a survey conducted by the Central Agricultural Office of Hungary, 67 food samples including beverages were taken from 57 food industrial and catering companies, 75% of them being small and medium-sized enterprises (SMEs). Moreover, 40% of the SMEs were micro entities. Water used for food processing was simultaneously sampled. The arsenic (As) content of solid food stuff was determined by hydride generation atomic absorption spectrometry after dry ashing. Food stuff with high water content and water samples were analyzed by inductively coupled plasma mass spectrometry. The As concentration exceeded 10 µg/L in 74% of the water samples taken from SMEs. The As concentrations of samples with high water content and water used were linearly correlated. Estimated As intake from combined exposure to drinking water and food of the population was on average 40% of the daily lower limit of WHO on the benchmark dose for a 0.5% increased incidence of lung cancer (BMDL0.5) for As. Five settlements had higher As intake than the BMDL0.5. Three of these settlements are situated in Csongrád county and the distance between them is less than 55 km. The maximum As intake might be 3.8 µg/kg body weight.


Assuntos
Arsênio/análise , Contaminação de Alimentos/análise , Manipulação de Alimentos , Poluentes Químicos da Água/análise , Animais , Pão/análise , Ovos/análise , Humanos , Hungria , Neoplasias Pulmonares/epidemiologia , Espectrometria de Massas/métodos , Leite/química , Nível de Efeito Adverso não Observado , Abastecimento de Água/análise
19.
Food Chem ; 141(2): 1301-5, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23790917

RESUMO

Kinetics of pre-column derivatization with 9-xanthydrol for the determination of ethyl carbamate (EC) in wine by a previous high performance liquid chromatographic method with fluorescence detection was studied and further developed. The life-time of the derivatized product and its excitation/absorption spectra were systematically investigated. Using low acidity (pH=2.5 set by phosphate buffers) only 3% of 9-xanthyl ethyl carbamate (XEC) decomposes in ∼48h, allowing a prolonged storage time of the derivatized EC conferring more accurate determination for large sample batches. Detection limit of this method is 3µgL(-1), while its average recovery is 98.5±4.9%. Calibration is linear up to 400µgL(-1). The EC content in 33 Hungarian wine samples ranges from 4.9 to 39.9µgL(-1) (average: 17.7µgL(-1), median: 16.7µgL(-1)), while only three of them was slightly over 30µgL(-1) EC, it being the maximum allowed concentration in countries already having legislation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Uretana/análise , Vinho/análise , Limite de Detecção
20.
Sci Total Environ ; 458-460: 451-8, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23688967

RESUMO

Carbonated and non-carbonated mineral water samples bottled in 0.5-L, 1.5-L and 2.0-L polyethylene terephthalate (PET) containers belonging to three different water brands commercialized in Hungary were studied in order to determine their phthalate content by gas chromatography-mass spectrometry. Among the six investigated phthalates, diisobutyl phthalate, di-n-butyl-phthalate, benzyl-butyl phthalate and di(2-ethyl-hexyl) phthalate (DEHP) were determined in non-carbonated samples as follows: <3.0 ng L(-1)-0.2 µg L(-1), <6.6 ng L(-1)-0.8 µg L(-1), <6.0 ng L(-1)-0.1 µg L(-1) and <16.0 ng L(-1)-1.7 µg L(-1), respectively. Any of the above-mentioned phthalate esters could be detected in carbonated mineral water samples. DEHP was the most abundant phthalate in the investigated samples. It could be detected after 44 days of storage at 22 °C and its leaching was the most pronounced when samples were stored over 1200 days. Mineral water purchased in PET bottles of 0.5L had the highest phthalate concentrations compared to those obtained for waters of the identical brand bottled in 1.5-L or 2.0-L PET containers due to the higher surface/volume ratio. No clear trend could be established for phthalate leaching when water samples were kept at higher temperatures (max. 60 °C) showing improper storage conditions. Phthalate determination by pyrolysis-gas chromatography/mass spectrometric measurements in the plastic material as well as in the aqueous phase proved the importance of the quality of PET raw material used for the production of the pre-form (virgin vs. polymer containing recycled PET).


Assuntos
Água Carbonatada/análise , Água Potável/química , Águas Minerais/análise , Ácidos Ftálicos/análise , Polietilenotereftalatos/química , Dibutilftalato/análogos & derivados , Dietilexilftalato , Cromatografia Gasosa-Espectrometria de Massas , Hungria , Temperatura
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