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1.
Water Sci Technol ; 82(5): 998-1008, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33031076

RESUMO

The feasibility of an advanced oxidation process based upon sodium persulfate (SPS) activated simultaneously by heat (50 °C) and nanoscale zero-valent iron (nZVI) on benzene removal was investigated. The experimental results strongly showed the synergistic effect of thermal and nZVI activation to SPS and benzene removal was enhanced with the increase of SPS/nZVI/benzene molar ratio. Specifically, 94% of benzene could be removed in 1 hr at 50 °C at the SPS/nZVI/benzene molar ratio of 10/5/1. The radical scavenger tests and electron paramagnetic resonance (EPR) analysis confirmed that SO4•- was the predominant species contributing to benzene degradation. Further, the effects of the solution matrix on benzene elimination were investigated. The results indicated that benzene destruction in the thermally activated SPS/nZVI system performed better under acidic conditions, and the high concentration of both Cl- and HCO3- had adverse effects on benzene elimination. The test for the performance of benzene degradation in the actual groundwater demonstrated that benzene could be degraded entirely at SPS/nZVI/benzene molar ratio of 40/40/1 at 50 °C, indicating that the synergistic catalysis of thermal and nZVI activation to SPS is exploitable and the thermally activated SPS/nZVI system can be applicable to the remediation of benzene contaminated groundwater.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Benzeno , Ferro , Oxirredução , Poluentes Químicos da Água/análise
2.
J Environ Qual ; 49(3): 654-662, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016401

RESUMO

Continuous-flow iron and bio-iron columns were used to evaluate the effects of seepage velocity and concentration on Cr(VI) removal from groundwater. Solid-phase analysis showed that microorganisms accelerated iron corrosion by excreting extracellular polymeric substances and generated highly reactive minerals containing Fe(II), which gave the bio-iron column a longer life span and enhanced capacity for Cr(VI) removal via enhanced adsorption and reduction by reactive minerals. The bio-iron column showed much higher Cr(VI) removal capacity than the iron column with increasing Cr(VI) loading, which was obtained by increasing the seepage velocity or influent Cr(VI) concentration from 95 to 1138 m yr-1 and from 5 to 40 mg L-1 , respectively. When the Cr(VI) loading varied in a range of 0 to 10 mg L-1 h-1 , the bio-iron column had a 60% longer longevity and one- to sixfold higher Cr(VI) elimination capacity than the iron column. This result indicated that, under fluctuating hydraulic conditions [e.g., seepage velocity and Cr(VI) concentration], the presence of microorganisms can significantly boost Cr(VI) removal using Fe0 -based permeable reactive barriers.


Assuntos
Água Subterrânea , Poluentes Químicos da Água/análise , Adsorção , Cromo , Ferro
3.
J Environ Qual ; 49(2): 358-367, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016432

RESUMO

In this work, the use of a coupled process, alkyl glycoside (APG) enhanced soil desorption followed by the zero-valent iron-ethylenediaminetetraacetic acid (EDTA)-air (ZEA) Fenton-like system, was investigated for the remediation of a simulated hexachlorobenzene (HCB)-contaminated diatomite soil and a real HCB-contaminated soil. Three surfactants with different concentrations were studied to obtain the suitable soil desorption agent. Compared with APG0810 and Triton x-100, APG0814 showed a better solubilization effect due to its lower critical micelle concentration. With addition of 3000 mg L-1 APG0814, 35% of HCB was removed from contaminated diatomite soil, and a small amount of residual APG in diatomite soil was found to be beneficial for the soil dispersion. After treatment with the ZEA system, the removal efficiency of HCB in the diatomite soil desorption solution reached 76% in 2 h; we observed that a small amount of APG retained in the desorption solution accelerated the HCB removal. A real HCB-contaminated soil was used to verify the remediation effects. This study demonstrates that our approach is a feasible alternative for remediating soil contaminated with hydrophobic organic compounds.


Assuntos
Recuperação e Remediação Ambiental , Poluentes do Solo/análise , Ácido Edético , Glicosídeos , Hexaclorobenzeno , Ferro , Solo
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1464-1467, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067938

RESUMO

OBJECTIVE: To investigate the prognostic significance of CUEDC1 in patients with acute myeloid leukemia (non-M3). METHODS: 52 cases newly diagnosed AML (non-M3) were selected and enrolled in AML non-M3 group, at the same time, 10 cases of iron doficiency anemia were selected and enrolled in control group. The bone marrow mononuclear cells(BMMC) were isolated from bone marrow of patients, the expression level of CUEDC1 in BMMC was detected by RT-PCR, the expression level of CUEDC1 mRNA in BMMC of AML-subtype patients was compared. The AML patients were divided into low and high expression groups according to the expression level of CUEDC1 mRNA, and the complete remission rate after the first chemothrapy course was compared, and the relative expression level of CUEDC1 mRNA between the remission and the non-remission group were compared. RESULTS: CUEDC1 was expressed in BMMC of 52 newly diagnosed patients with AML (non-M3) of all subtypes, which was higher than that in control group (P<0.05), and the expression level of CUEDC1 mRNA in M5 patients was the highest (P<0.05). In CUEDC1 low expression group, induced complete remisson rate (76.2%,16/21) after the first course of treatment seemed higher than that of the high expression group(67.7%,21/31), but the difference was not statistically significant; the expression level of CUEDC1 mRNA in the remission group of patients with newly diagnosed AML(non-M3) was lower than that in the non-remission group(P<0.05). CONCLUSION: CUEDC1 is highly expressed in newly diagnosed patients with AML, among which the CUEDC1 mRNA expression level in M5 patients is the highest, the expression of CUEDC1 mRNA possibly relates to the prognosis of patients with AML.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda , Medula Óssea , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Ferro , Prognóstico , RNA Mensageiro/genética
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2266-2269, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018459

RESUMO

This paper describes a method for deciphering major drivers of bacterial stress response using an empirically informed computational approach. We develop a working model of iron flux regulation and concomitant oxidative stress response in Escherichia coli. The integrated model is used to investigate the temporal effects of iron and hydrogen peroxide stress on bacterial growth and metabolism. We employ a sensitivity analysis platform and, using various measures, probe for major mechanistic drivers of the bacterial response to iron stress.


Assuntos
Peróxido de Hidrogênio , Ferro , Bactérias , Oxirredução , Estresse Oxidativo
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2270-2273, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018460

RESUMO

Iron plays important roles in healthy brain but altered homeostasis and concentration have been correlated to aging and neurodegenerative diseases. Iron enters the central nervous system by crossing the brain barrier systems: the Blood- Brain Barrier separating blood and brain and the Blood-Cerebrospinal Fluid Barrier (BCSFB) between blood and CSF, which is in contact with the brain by far less selective barriers. Herein, we develop a two-compartmental model for the BCSFB, based on first-order ordinary differential equations, performing numerical simulations and sensitivity analysis. Furthermore, as input parameters of the model, experimental data from patients affected by Alzheimer's disease, frontotemporal dementia, mild cognitive impairment and matched neurological controls were used, with the aim of investigating the differences between physiological and pathological conditions in the regulation of iron passage between blood and CSF which can be possibly targeted by therapy.


Assuntos
Doenças Neurodegenerativas , Barreira Hematoencefálica , Encéfalo , Humanos , Ferro , Modelos Teóricos
7.
Water Sci Technol ; 82(7): 1339-1349, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33079714

RESUMO

Flax straw biochar (FSBC)-supported nanoscale zero-valent iron (nZVI) composite (nZVI-FSBC) combining the advantages of nZVI and biochar was synthesized and tested for Cr(VI) removal efficiency from aqueous solution. Surface morphology and structure of FSBC and nZVI-FSBC were characterized by scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller techniques, which help to clarify the mechanism of Cr(VI) removal from aqueous solution. The adsorption of Cr(VI) onto FSBC and nZVI-FSBC was best described by the pseudo-second-order and the Sips model. Compared with FSBC, nZVI-FSBC remarkably improved the performance in removing Cr(VI) under identical experimental conditions. Due to the collaborative effect of adsorption and reduction of nZVI-FSBC, the adsorption capacity of nZVI-FSBC for Cr(VI) is up to 186.99 mg/g. The results obtained by XPS, XRD, and FTIR confirmed that adsorption and reduction dominated the processes of Cr(VI) removal by nZVI-FSBC. As a supporter, FSBC not only improved the dispersion of nZVI, but also undertook the adsorption task of Cr(VI) removal. The surface oxygen-containing functional groups of nZVI-FSBC mainly participated in the adsorption part, and the nZVI promoted the Cr(VI) removal through the redox reactions. These observations indicated that the nZVI-FSBC can be considered as potential adsorbents to remove Cr(VI) for environment remediation.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cromo , Poluentes Químicos da Água/análise
9.
Water Sci Technol ; 82(1): 185-193, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32910802

RESUMO

Orange G (OG), a typical azo dye in textile wastewaters, has been the subject of intense investigations. This study investigated oxidative degradation of OG in aqueous solution by persulfate (PS) activated with pyrite. A complete destruction of OG was achieved within 60 min in the pyrite/PS system. Lower solution pH, smaller pyrite particles and higher pyrite dosage was beneficial for OG degradation. Higher PS concentration was also in favour of OG degradation, but excess PS would decrease the removal efficiency of OG. The addition of HCO3- and H2PO4- but Cl- had inhibitory effects on the destruction of OG. The results of quenching experiments and electron paramagnetic resonance tests proved that SO4•- and •OH were the dominant reactive species responsible for OG degradation in the pyrite/PS system. The azo bond, naphthalene ring and benzene ring of OG were all destroyed by the generated reactive species. The mineralization rate of OG reached 34.4% after 60 min of reaction. This work will provide information for understanding azo dye degradation by pyrite activated PS.


Assuntos
Compostos Azo , Sulfatos , Ferro , Estresse Oxidativo , Sulfetos
10.
Ann Hematol ; 99(11): 2507-2512, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32918595

RESUMO

Iron overload comprises one of the main complications of congenital dyserythropoietic anemia type I (CDA-I). When analyzing magnetic resonance imaging T2* (MRI T2*) results in CDA patients, two previous studies reported discordant results regarding iron load in these patients. To further understand iron loading pattern in this group of patients, we analyzed MRI T2* findings in 46 CDA-I patients. Mild to moderate hepatic iron overload was detected in 28/46 (60.8%) patients. A significant correlation was found between serum ferritin and liver iron concentration (LIC). A significant correlation (p value = 0.02) was also found between the patient's age and LIC, reflecting increased iron loading over time, even in the absence of transfusion therapy. Notably, no cardiac iron overload was detected in any patient. Transfusion-naive patients had better LIC and better cardiac T2* values. These results demonstrate that a high percentage of CDA-I patients have liver iron concentration above the normal values, risking them with significant morbidity and mortality, and emphasize the importance of periodic MRI T2* studies for direct assessment of tissue iron concentration in these patients, taking age and transfusional burden into consideration.


Assuntos
Anemia Diseritropoética Congênita , Sobrecarga de Ferro , Ferro/sangue , Fígado , Imagem por Ressonância Magnética , Miocárdio/metabolismo , Adolescente , Adulto , Anemia Diseritropoética Congênita/sangue , Anemia Diseritropoética Congênita/diagnóstico por imagem , Criança , Pré-Escolar , Ferritinas/sangue , Seguimentos , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/diagnóstico por imagem , Fígado/diagnóstico por imagem , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Ecotoxicol Environ Saf ; 203: 111010, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888587

RESUMO

Manganese (Mn) toxicity is common in plants grown on very acid soils. However, some plants species that grow in this condition can take up high amounts of Mn and are referred to as hyperaccumulating species. In this study, we evaluated the capacity of Ilex paraguariensis to accumulate Mn and the effect of excessive concentrations on plant growth and nutrition. For this, a container experiment was conducted using soils from different parent materials (basalt and sandstone), with and without liming, and at six doses of applied Mn (0, 30, 90, 270, 540 and 1,080 mg kg-1). Clonal plants grown for 203 days were harvested to evaluate yield, and leaf tissue samples were evaluated for Mn and other elements. Without liming and with high Mn doses, leaf Mn concentrations reached 13,452 and 12,127 mg kg-1 in sandstone and basalt soils, respectively; concentrations in excess of 10,000 mg kg-1 are characteristic of hyperaccumulating plants. Liming reduced these values to 7203 and 8030 mg kg-1. More plant growth accompanied increased Mn leaf concentrations, with a growth reduction noted at the highest dose in unlimed soils. Elemental distribution showed Mn presence in the mesophyll, primarily in vascular bundles, without high Mn precipitates. Interveinal chlorosis of young leaves associated with high Mn concentration and lower Fe concentrations was observed, especially in sandstone soil without liming. However, the occurrence of this symptom was not associated with decreased plant growth.


Assuntos
Ácidos/farmacologia , Ilex paraguariensis/metabolismo , Manganês/metabolismo , Doenças das Plantas/induzido quimicamente , Poluentes do Solo/metabolismo , Ácidos/análise , Compostos de Cálcio/análise , Compostos de Cálcio/farmacologia , Ilex paraguariensis/efeitos dos fármacos , Ilex paraguariensis/crescimento & desenvolvimento , Ferro/metabolismo , Manganês/análise , Manganês/toxicidade , Óxidos/análise , Óxidos/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
12.
Chemosphere ; 254: 126899, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957294

RESUMO

In this study, the reduction of iron-carbon internal electrolysis was reinforced by persulfate for p-nitrophenol removal. The effects of persulfate dosage, initial pH and iron-carbon mass ratio were comprehensively studied in batch experiments. In the system of iron-carbon internal electrolysis coupled with persulfate, the iron-carbon internal electrolysis and persulfate had a significant mutual influence, exhibiting a wide range of pH in the treatment process. Moreover, the coupled system also showed the remarkable removal and degradation efficiency of p-nitrophenol according to the contrast experiments. The satisfactory results should be attributed to the potential reduction of iron-carbon internal electrolysis, which was stimulated by persulfate to transform the nitro group to the amine group, accompanying the subsequent oxidation. Furthermore, persulfate possessed the ability that the dynamically destructive effect on external and internal of Fe0 and the scavenging action on activated carbon, effectively strengthening the potential energy for release and transfer of reductive substances. Both HO• and SO4•- as the main free radicals were formed to mineralize the intermediates in the coupled system. These findings indicate that the system of iron-carbon internal electrolysis coupled with persulfate can be a promising strategy for the treatment of the toxic and refractory wastewater.


Assuntos
Carvão Vegetal/química , Eletrólise/métodos , Ferro/química , Nitrofenóis/análise , Sulfatos/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Modelos Teóricos , Nitrofenóis/química , Oxirredução , Águas Residuárias/química , Poluentes Químicos da Água/química
13.
Chemosphere ; 254: 126909, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957299

RESUMO

Soil contamination by heavy metals (HMs) is an environmental problem, and nanoremediation by using zero-valent iron nanoparticles (nZVI) has attracted increasing interest. We used ecotoxicological test and global transcriptome analysis with DNA microarrays to assess the suitability of C. elegans as a useful bioindicator to evaluate such strategy of nanoremediation in a highly polluted soil with Pb, Cd and Zn. The HMs produced devastating effect on C. elegans. nZVI treatment reversed this deleterious effect up to day 30 after application, but the reduction in the relative toxicity of HMs was lower at day 120. We stablished gene expression profile in C. elegans exposed to the polluted soil, treated and untreated with nZVI. The percentage of differentially expressed genes after treatment decreases with exposure time. After application of nZVI we found decreased toxicity, but increased biosynthesis of defensive enzymes responsive to oxidative stress. At day 14, when a decrease in toxicity has occurred, genes related to specific heavy metal detoxification mechanisms or to response to metal stress, were down regulated: gst-genes, encoding for glutathione-S-transferase, htm-1 (heavy metal tolerance factor), and pgp-5 and pgp-7, related to stress response to metals. At day 120, we found increased HMs toxicity compared to day 14, whereas the transcriptional oxidative and metal-induced responses were attenuated. These findings indicate that the profiled gene expression in C. elegans may be considered as an indicator of stress response that allows a reliable evaluation of the nanoremediation strategy.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Ferro/química , Metais Pesados/toxicidade , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Poluentes do Solo/toxicidade , Transcrição Genética/efeitos dos fármacos , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Ecotoxicologia , Nanopartículas Metálicas , Metais Pesados/análise , Estresse Oxidativo/genética , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise , Toxicogenética
14.
Environ Monit Assess ; 192(10): 619, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32885322

RESUMO

The present state of iron (Fe) and manganese (Mn) concentration in groundwater of Changchun city located within the Songnen Plain of northeastern China was evaluated in this study. Heavy metal sources, as well as triggering mechanism, were analyzed using a physicochemical, statistical and spatial approach. Results revealed that out of the 2600 samples analyzed, 214 (representing 8.24%) for Fe and 606 wells (representing 23.34%) for Mn exceeded the water standard. Organic matter-rich sediments and Fe-Mn nodules in aquifer and soil serve as sources of Fe and Mn. Organic and inorganic complex formations, as well as long residence time, were found to foster the release of Fe and Mn into groundwater. Additionally, pH and well depth was important in triggering Mn dissolution while groundwater mineralization, depth to the water table and well proximity to the river were found to have minimal/negligible effect on heavy metal mobilization. The removal of Fe and Mn from the water before use was proposed along with the sinking of deeper wells for groundwater exploitation to limit the use of polluted water.


Assuntos
Água Subterrânea , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Ferro/análise , Manganês/análise
15.
J Environ Sci (China) ; 97: 110-119, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933726

RESUMO

FeVO4/CeO2 was applied in the electro-Fenton (EF) degradation of Methyl Orange (MO) as a model of wastewater pollution. The results of the characterization techniques indicate that FeVO4 with triclinic structure and face-centered cubic fluorite CeO2 maintained their structures during the nanocomposite synthesis. The effect of applied current intensity, initial pollutant concentration, initial pH, and catalyst weight was investigated. The MO removal reached 96.31% and chemical oxygen demand (COD) removal 70% for 60 min of the reaction. The presence of CeO2 in the nanocomposite plays a key role in H2O2 electro-generation as a significant factor in the electro-Fenton (EF) system. The metal leaching from FeVO4/CeO2 was negligible (cerium 4.1%, iron 4.3%, and vanadium 1.7%), which indicates that the active species in the nanocomposite are strongly interacting with each other and are stable. The performance of the nanocatalyst in real wastewaters, salty, and binary systems was acceptable and the pollutions were removed efficiently. The synergistic effect between V, Fe, and Ce could be account as the reason for the respectable function of FeVO4/CeO2. The electron transfer proceeds via Haber-Weiss mechanism. A degradation pathway was proposed through by-products analysis using gas chromatography-mass spectrometry (GC-MS) technique. The pseudo-first-order kinetic model described the obtained experimental results (R2 = 0.9906). The electro-Fenton system efficiency was improved by adding persulfate. The nanocomposite preserved almost its efficiency after six cycles. The obtained results demonstrate that the synergistic catalyst (FeVO4/CeO2) has the capability to introduce as a promising replacement of conventional catalysts in the electro-Fenton processes with brilliant proficiency.


Assuntos
Nanocompostos , Poluentes Químicos da Água/análise , Catálise , Peróxido de Hidrogênio , Ferro , Oxirredução , Águas Residuárias
17.
Ecotoxicol Environ Saf ; 203: 111054, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888616

RESUMO

Quinclorac (3,7-dichloroquinoline-8-carboxylic acid, QNC) is a highly selective auxin herbicide that is typically applied to paddy rice fields. Its residue is a serious problem in crop rotations. In this study, Oryza sativa L. seedlings was used as a model plant to explore its biochemical response to abiotic stress caused by QNC and nZVI coexposure, as well as the interactions between QNC and nZVI treatments. Exposure to 5 and 10 mg/L QNC reduced the fresh biomass by 26.6% and 33.9%, respectively, compared to the control. The presence of 50 and 250 mg/L nZVI alleviated the QNC toxicity, but the nZVI toxicity was aggravated by the coexist of QNC. Root length was enhanced upon exposure to low or medium doses of both QNC and nZVI, whereas root length was inhibited under high-dose coexposure. Both nZVI and QNC, either alone or in combination, significantly inhibited the biosynthesis of chlorophyll, and the inhibition rate increased with elevated nZVI and QNC concentration. It was indicated that nZVI or QNC can affect the plant photosynthesis, and there was a significant interaction between the two treatments. Effects of QNC on the antioxidant response of Oryza sativa L. differed in the shoots and roots; generally, the introduction of 50 and 250 mg/L nZVI alleviated the oxidative stress (POD in shoots, SOD and MDA in roots) induced by QNC. However, 750 mg/kg nZVI seriously damaged Oryza sativa L. seedlings, which likely resulted from active iron deficiency. QNC could be removed from the culture solution by nZVI; as a result, nZVI suppressed QNC uptake by 20%-30%.


Assuntos
Antioxidantes/metabolismo , Ferro/toxicidade , Nanopartículas/toxicidade , Oryza/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quinolinas/toxicidade , Poluentes do Solo/toxicidade , Transporte Biológico , Biomassa , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
18.
J Toxicol Sci ; 45(9): 539-548, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32879253

RESUMO

We investigated the mechanism underlying intestinal cadmium (Cd) uptake based on the mediators (metal transporters) of essential elements, such as Fe, Zn, Cu, and Ca, under normal conditions in female rats. These elements interact with Cd uptake from the intestinal tract. Cd concentration at each site of the small intestine (duodenum, jejunum, and ileum) increased as Cd exposure increased. However, Cd concentration was the highest in the duodenum. The gene expression of ZIP14, DMT1, and ATP7A increased with increase in Cd concentration. Further, Cu concentration decreased as Cd concentration increased. In contrast, Fe concentration displayed a decreasing tendency with the increase in Cd concentration. The gene expression levels of ZIP14, DMT1, and ATP7A were positively correlated with Cd concentration. Immunohistochemical staining revealed the positive sites of ZIP14 and DMT1 scattered in the area adjacent to the goblet cells, resorbable epithelial cells, and lamina propria in the duodenum tissue, according to the increase in Cd concentration. Cd is induced to synthesize and bind to metallothionein (MT-I and -II) and accumulate in the intestinal tissues, mainly in the duodenum. Such findings suggest that Cd, a contaminant element, is taken up from the intestinal tract by multiple metal transporters such as Cu, Fe, and Zn, thereby involving in the intestinal Cd absorption.


Assuntos
Cádmio/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Absorção Intestinal/genética , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Animais , Proteínas de Transporte de Cátions/genética , Cobre , ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Duodeno/metabolismo , Feminino , Expressão Gênica , Ferro , Metalotioneína/metabolismo , Ratos , Zinco
19.
Chemosphere ; 254: 126763, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957263

RESUMO

Epidemiologic studies suggest that circulating metals from the natural environment are linked with cardiometabolic health. However, few studies examined the relationship between multiple metals exposure and metabolic phenotypes, especially in obese individuals. We conducted a cross-sectional study to explore the association between 23 urinary metals and metabolic phenotypes in 1392 overweight and obese individuals (592 males, 800 females, mean age 43.1 ± 9.8 years). Participants were classified as metabolically unhealthy if they had ≥2 of the following metabolic abnormalities: elevated blood pressure, elevated fasting blood glucose, elevated triglycerides, and reduced high-density lipoprotein cholesterol. Odds ratios (ORs) of unhealthy metabolic phenotypes for metal levels categorized into tertiles were assessed using logistic regression models. Five metals (barium, copper, iron, uranium, and zinc) were associated with unhealthy metabolic phenotypes in single-metal models, while in the multiple-metal model, only zinc and zinc-copper ratio remained significant. The ORs (95% CIs) comparing extreme tertiles were 2.57 (1.69, 3.89) for zinc and 1.68 (1.24, 2.27) for zinc-copper ratio after adjustment for confounders (both p-trends were <0.001). The numbers of metabolic abnormalities significantly increased with the levels of zinc and the zinc-copper ratio increased. Similar associations were observed with metabolic syndrome risk. High levels of urinary zinc were positively associated with elevated fasting blood glucose (p-trend < 0.001) and elevated triglycerides (p-trend = 0.003). The results suggest that urinary zinc and zinc-copper ratio are positively associated with increased risk of unhealthy metabolic phenotype. Further prospective studies with a larger sample size are required to verify these findings.


Assuntos
Exposição Ambiental , Metais/urina , Obesidade , Adulto , HDL-Colesterol , Cobre , Estudos Transversais , Feminino , Humanos , Ferro , Modelos Logísticos , Masculino , Síndrome Metabólica , Pessoa de Meia-Idade , Razão de Chances , Sobrepeso , Fenótipo , Estudos Prospectivos , Zinco
20.
Chemosphere ; 254: 126792, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957266

RESUMO

Iron oxide nanoparticles (IONPs) are used in several medical and environmental applications, but their mechanism of action and hazardous effects to early developmental stages of fish remain unknown. Thus, the present study aimed to assess the developmental toxicity of citrate-functionalized IONPs (γ-Fe2O3 NPs), in comparison with its dissolved counterpart, in zebrafish (Danio rerio) after static and semi-static exposure. Embryos were exposed to environmental concentrations of both iron forms (0.3, 0.6, 1.25, 2.5, 5 and 10 mg L-1) during 144 h, jointly with negative control group. The interaction and distribution of both Fe forms on the external chorion and larvae surface were measured, following by multiple biomarker assessment (mortality, hatching rate, neurotoxicity, cardiotoxicity, morphological alterations and 12 morphometrics parameters). Results showed that IONPs were mainly accumulated on the zebrafish chorion, and in the digestive system and liver of the larvae. Although the IONPs induced low embryotoxicity compared to iron ions in both exposure conditions, these nanomaterials induced sublethal effects, mainly cardiotoxic effects (reduced heartbeat, blood accumulation in the heart and pericardial edema). The semi-static exposure to both iron forms induced high embryotoxicity compared to static exposure, indicating that the nanotoxicity to early developmental stages of fish depends on the exposure system. This is the first study concerning the role of the exposure condition on the developmental toxicity of IONPs on fish species.


Assuntos
Compostos Férricos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cloretos , Embrião não Mamífero/efeitos dos fármacos , Ferro/farmacologia , Larva/efeitos dos fármacos , Nanopartículas/toxicidade , Peixe-Zebra/embriologia
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