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1.
Int J Mol Sci ; 22(10)2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34064906

RESUMEN

Nerve growth factor (NGF) is a protein essential to neurons survival, which interacts with its receptor as a non-covalent dimer. Peptides belonging to NGF N-terminal domain are able to mimic the activity of the whole protein. Such activity is affected by the presence of copper ions. The metal is released in the synaptic cleft where proteins, not yet identified, may bind and transfer to human copper transporter 1 (hCtr1), for copper uptake in neurons. The measurements of the stability constants of copper complexes formed by amyloid beta and hCtr1 peptide fragments suggest that beta-amyloid (Aß) can perform this task. In this work, the stability constant values of copper complex species formed with the dimeric form of N-terminal domain, sequence 1-15 of the protein, were determined by means of potentiometric measurements. At physiological pH, NGF peptides bind one equivalent of copper ion with higher affinity of Aß and lower than hCtr1 peptide fragments. Therefore, in the synaptic cleft, NGF may act as a potential copper chelating molecule, ionophore or chaperone for hCtr1 for metal uptake. Copper dyshomeostasis and mild acidic environment may modify the balance between metal, NGF, and Aß, with consequences on the metal cellular uptake and therefore be among causes of the Alzheimer's disease onset.


Asunto(s)
Transportador de Cobre 1/metabolismo , Cobre/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Fragmentos de Péptidos/metabolismo , Sitios de Unión , Humanos , Unión Proteica
2.
Sci Total Environ ; 784: 147221, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34088078

RESUMEN

Semiconductor nanomaterials not only bring great convenience to peoples lives but also become a potential hazard to human health. The purpose of this study was to evaluate the toxicity of CuS/CdS nanocomposites in hepatocytes and mice liver. The CuS/CdS semiconductor nanocomposites were synthesized by a biomimetic synthesis - ion exchange strategy. Nanosize was confirmed by high-resolution transmission electron microscopy and dynamic light scattering. The composition and physical properties were measured by powder X-ray diffraction, Fourier transform infrared spectra, atomic absorption spectroscopy, thermogravimetry-differential scanning calorimetry and zeta potential analysis. The results revealed that CuS/CdS nanocomposites had 8.7 nm diameter and negative potential. Ion exchange time could adjust the ratio of CuS and CdS in nanocomposites. The toxicological study revealed that CuS/CdS nanocomposites could be internalized into liver cells, inhibited endogenous defense system (e.g. GSH and SOD), induced the accumulation of oxidation products (e.g. ROS, GSSG and MDA), and caused hepatocyte apoptosis. The in vivo experiments in Balb/c mice showed that the experimental dose (4 mg/kg) didn't cause observable changes in mice behavior, physical activity and pathological characteristics, but the continuous accumulation of Cd2+ in the liver and kidney might be responsible for its long-term toxicity.


Asunto(s)
Nanocompuestos , Animales , Cobre , Hepatocitos , Hígado , Ratones , Nanocompuestos/toxicidad , Semiconductores , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
3.
BMC Genomics ; 22(1): 416, 2021 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-34090338

RESUMEN

BACKGROUND: Copper was used for many years in aquaculture operations as an effective algaecide or a parasite treatment of fish. It is an essential nutrient with numerous functions in organisms, but is toxic at high concentrations. However, the toxicity of copper to fish remains unclear. In this study, we used the piebald naked carp, Gymnocypris eckloni, as a model. RNA-seq data from different tissues, including gills, kidney, and liver, were used to investigate the underlying mechanism of copper toxicology in G. eckloni. RESULTS: We compared the transcriptomes from different tissues with different time durations of copper ion treatment. After 72 h copper ion treatment, the number of genes with different expression in gills and liver changed dramatically, but not in kidneys. In KEGG functional enrichment, the pattern of differentially expressed genes (DEGs) was also similar in the gills and liver. The most enriched pathway of DEGs was "Ribosome" in both tissues. Furthermore, we analyzed the expression levels of genes involved in oxidative stress response and protein synthesis using qPCR and RNA-seq data. Our results showed that several genes involved in oxidative stress response were up-regulated both in gills and liver. Up-regulation of these genes indicated that copper treatment caused oxidative stress, which is likely to result in ribosome damage. In addition, our results showed that the expression of Eef1b2, a transcription elongation factor, was decreased in the liver under oxidative stress, and the expression of translation initiation factors Eif4ebp1 and eIF2α, and elongation factor eEF2 was up-regulated. These results supported the idea that oxidative stress inhibits protein synthesis in cells. CONCLUSIONS: Our results indicate that copper exposure caused different responses in different tissues, since the gene expression patterns changed substantially either in the gills or liver, while the effect on the kidney was relatively weak. Furthermore, our results indicated that the expression pattern of the genes involved in the ribosome, which is a complex molecular machine orchestrating protein synthesis in the cell, together with translation initiation factor and elongation factors, were affected by copper exposure both in the gills and liver of piebald naked carp. This result leads us to speculate that the downregulation of global protein synthesis is an acute response strategy of fish to metal-induced oxidative stress. Moreover, we speculate that this strategy not only exists in the selective translation of proteins but also exists in the specific translation of functional proteins in tissues and cells.


Asunto(s)
Carpas , Animales , Carpas/genética , Cobre/toxicidad , Perfilación de la Expresión Génica , Branquias , Transcriptoma
4.
Water Sci Technol ; 83(11): 2753-2761, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34115629

RESUMEN

Heterogeneous photocatalysis using nanocomposites is of great research interest in the treatment of industrial wastewater. The impregnated photocatalyst was produced by liquid state reaction of ZnO/CuO nanocomposite with extracted eggshells. The structure, functional group, metal composition, bandgap, and photocatalytic activity of the nanocomposites were characterized by using X-ray diffraction, Fourier-transform infrared spectroscopy, atomic absorption spectrometry, and UV-Vis spectroscopy, respectively, in the absence and presence of eggshells. Photocatalytic degradation activities of the nanocomposites under UV light irradiation have been tested for a real sewage sample taken from Debre Berhan Textile Industry. From the results, the optimized degradation efficiency of the dye was 97.95% with 0.4 g dose of the photocatalyst, 120 min irradiation time, 120 °C temperature, and pH of 6.7. The results revealed that eggshell impregnated nanocomposite had better catalytic activity than the naked nanocomposite. This is due to the highly porous structure of eggshell biomasses and their sorption characteristics. In conclusion, when nanocomposites are supported by eggshell biomasses, they are excellent photocatalysts and can minimize the contamination of organic dyes from textile effluents.


Asunto(s)
Nanocompuestos , Óxido de Zinc , Animales , Catálisis , Colorantes , Cobre , Cáscara de Huevo , Residuos Industriales , Luz , Industria Textil , Textiles
5.
Int J Mol Sci ; 22(9)2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-34068728

RESUMEN

To mimic more realistic lung tissue conditions, co-cultures of epithelial and immune cells are one comparatively easy-to-use option. To reveal the impact of immune cells on the mode of action (MoA) of CuO nanoparticles (NP) on epithelial cells, A549 cells as a model for epithelial cells have been cultured with or without differentiated THP-1 cells, as a model for macrophages. After 24 h of submerged incubation, cytotoxicity and transcriptional toxicity profiles were obtained and compared between the cell culture systems. Dose-dependent cytotoxicity was apparent starting from 8.0 µg/cm2 CuO NP. With regard to gene expression profiles, no differences between the cell models were observed concerning metal homeostasis, oxidative stress, and DNA damage, confirming the known MoA of CuO NP, i.e., endocytotic particle uptake, intracellular particle dissolution within lysosomes with subsequent metal ion deliberation, increased oxidative stress, and genotoxicity. However, applying a co-culture of epithelial and macrophage-like cells, CuO NP additionally provoked a pro-inflammatory response involving NLRP3 inflammasome and pro-inflammatory transcription factor activation. This study demonstrates that the application of this easy-to-use advanced in vitro model is able to extend the detection of cellular effects provoked by nanomaterials by an immunological response and emphasizes the use of such models to address a more comprehensive MoA.


Asunto(s)
Epitelio/efectos de los fármacos , Nanopartículas del Metal/química , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Estrés Oxidativo/genética , Transcripción Genética/efectos de los fármacos , Células A549 , Diferenciación Celular/efectos de los fármacos , Línea Celular , Técnicas de Cocultivo , Cobre/química , Cobre/farmacología , Daño del ADN/efectos de los fármacos , Endocitosis/efectos de los fármacos , Humanos , Pulmón/efectos de los fármacos , Pulmón/patología , Macrófagos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
6.
Int J Mol Sci ; 22(10)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-34068879

RESUMEN

The redox chemistry of copper(II) is strongly modulated by the coordination to amyloid-ß peptides and by the stability of the resulting complexes. Amino-terminal copper and nickel binding motifs (ATCUN) identified in truncated Aß sequences starting with Phe4 show very high affinity for copper(II) ions. Herein, we study the oxidase activity of [Cu-Aß4-x] and [Cu-Aß1-x] complexes toward dopamine and other catechols. The results show that the CuII-ATCUN site is not redox-inert; the reduction of the metal is induced by coordination of catechol to the metal and occurs through an inner sphere reaction. The generation of a ternary [CuII-Aß-catechol] species determines the efficiency of the oxidation, although the reaction rate is ruled by reoxidation of the CuI complex. In addition to the N-terminal coordination site, the two vicinal histidines, His13 and His14, provide a second Cu-binding motif. Catechol oxidation studies together with structural insight from the mixed dinuclear complexes Ni/Cu-Aß4-x reveal that the His-tandem is able to bind CuII ions independently of the ATCUN site, but the N-terminal metal complexation reduces the conformational mobility of the peptide chain, preventing the binding and oxidative reactivity toward catechol of CuII bound to the secondary site.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Complejos de Coordinación/metabolismo , Cobre/metabolismo , Dopamina/metabolismo , Oxidorreductasas/metabolismo , Péptidos beta-Amiloides/química , Complejos de Coordinación/química , Cobre/química , Dopamina/química , Histidina/química , Histidina/metabolismo , Modelos Moleculares , Conformación Molecular , Oxidación-Reducción , Oxidorreductasas/química
7.
Clin Lab ; 67(6)2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34107631

RESUMEN

BACKGROUND: Essential trace elements play key roles in multiple biological systems, and hemodialysis patients are at risk for deficiency of essential trace elements. The aim of the study was to assess the essential element status in end stage renal disease patients undergoing online hemodiafiltration (online HDF) in outpatient dialysis clinic. METHODS: A total of 28 Korean patients with regular online HDF were included. Blood samples were collected before and after one HDF session, and serum concentrations of zinc, copper, selenium, and manganese were simulta-neously measured by inductively coupled plasma mass spectrometry. RESULTS: Selenium, zinc, copper deficiencies were observed in 71.4%, 35.8%, and 21.4%, compared with the reference range. No patients revealed manganese deficiency. After the HDF, the post-HDF level significantly increased in all trace elements, compared with the pre-HDF (11.2% for selenium, 10.7% for copper, and 6.6% for zinc). However, 50% patients were still deficient for selenium at the post-HDF. CONCLUSIONS: Our data suggest that the patients undergoing online HDF are at an increased risk of trace element deficiency, especially for selenium.


Asunto(s)
Hemodiafiltración , Selenio , Oligoelementos , Anciano , Cobre , Humanos , Zinc
8.
Talanta ; 232: 122439, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34074424

RESUMEN

Filamentous bacteriophages are viruses infecting only bacteria. In this study, phage display technique was applied to identify highly selective Cu(II) binding peptides. After five rounds of positive screening against Cu(II) and various rounds of negative screenings against competitive metal ions (Al(III), Co(II), Fe(III), Ni(II) and Zn(II)), bacteriophages were enriched. Selective Cu(II) binding of final phages was confirmed by Enzyme Linked Immunosorbent Assay (ELISA), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDX) analyses. 15 phage plaques were randomly selected and sequenced. Cu-5 peptide (HGFANVA) with the highest frequency of occurrence and the strongest Cu(II) affinity was chosen for further Cu(II) detection and removal tests. Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) confirmed the strong Cu(II) binding potential of engineered viruses. Cu-5 peptides were synthetically synthesized with three Cysteine units at C-terminal and a AuNP-peptide biosensor system was developed based on aggregation behavior of AuNPs upon Cu(II) ion treatment. AuNP-based Cu(II) sensor was selective for Cu(II) and the LOD was 91.15 nM (ca. 5.8 × 10-3 mg/L; 3σ/k, n = 5, R2 = 0.992) for the case study which is considerably lower than the WHO's accepted guideline of 1.3 mg/L. This study provides an interdisciplinary approach to apply short peptides as recognition units for biosensor studies which are user friendly, not bulky and cost-effective.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Colorimetría , Cobre , Compuestos Férricos , Oro , Péptidos
9.
Nutrients ; 13(6)2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34072977

RESUMEN

The trace element copper (Cu) is part of our nutrition and essentially needed for several cuproenzymes that control redox status and support the immune system. In blood, the ferroxidase ceruloplasmin (CP) accounts for the majority of circulating Cu and serves as transport protein. Both Cu and CP behave as positive, whereas serum selenium (Se) and its transporter selenoprotein P (SELENOP) behave as negative acute phase reactants. In view that coronavirus disease (COVID-19) causes systemic inflammation, we hypothesized that biomarkers of Cu and Se status are regulated inversely, in relation to disease severity and mortality risk. Serum samples from COVID-19 patients were analysed for Cu by total reflection X-ray fluorescence and CP was quantified by a validated sandwich ELISA. The two Cu biomarkers correlated positively in serum from patients with COVID-19 (R = 0.42, p < 0.001). Surviving patients showed higher mean serum Cu and CP concentrations in comparison to non-survivors ([mean+/-SEM], Cu; 1475.9+/-22.7 vs. 1317.9+/-43.9 µg/L; p < 0.001, CP; 547.2.5 +/- 19.5 vs. 438.8+/-32.9 mg/L, p = 0.086). In contrast to expectations, total serum Cu and Se concentrations displayed a positive linear correlation in the patient samples analysed (R = 0.23, p = 0.003). Serum CP and SELENOP levels were not interrelated. Applying receiver operating characteristics (ROC) curve analysis, the combination of Cu and SELENOP with age outperformed other combinations of parameters for predicting risk of death, yielding an AUC of 95.0%. We conclude that the alterations in serum biomarkers of Cu and Se status in COVID-19 are not compatible with a simple acute phase response, and that serum Cu and SELENOP levels contribute to a good prediction of survival. Adjuvant supplementation in patients with diagnostically proven deficits in Cu or Se may positively influence disease course, as both increase in survivors and are of crucial importance for the immune response and antioxidative defence systems.


Asunto(s)
COVID-19/sangre , COVID-19/mortalidad , Cobre/sangre , SARS-CoV-2/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios Transversales , Supervivencia sin Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Selenio/sangre , Selenoproteína P/sangre , Tasa de Supervivencia
10.
Chemosphere ; 276: 130162, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34088083

RESUMEN

Copper (Cu) ion in wastewater is considered as one of the crucial hazardous elements to be quantified. This research is established to predict copper ions adsorption (Ad) by Attapulgite clay from aqueous solutions using computer-aided models. Three artificial intelligent (AI) models are developed for this purpose including Grid optimization-based random forest (Grid-RF), artificial neural network (ANN) and support vector machine (SVM). Principal component analysis (PCA) is used to select model inputs from different variables including the initial concentration of Cu (IC), the dosage of Attapulgite clay (Dose), contact time (CT), pH, and addition of NaNO3 (SN). The ANN model is found to predict Ad with minimum root mean square error (RMSE = 0.9283) and maximum coefficient of determination (R2 = 0.9974) when all the variables (i.e., IC, Dose, CT, pH, SN) were considered as input. The prediction accuracy of Grid-RF model is found similar to ANN model when a few numbers of predictors are used. According to prediction accuracy, the models can be arranged as ANN-M5> Grid-RF-M5> Grid-RF-M4> ANN-M4> SVM-M4> SVM-M5. Overall, the applied statistical analysis of the results indicates that ANN and Grid-RF models can be employed as a computer-aided model for monitoring and simulating the adsorption from aqueous solutions by Attapulgite clay.


Asunto(s)
Inteligencia Artificial , Cobre , Adsorción , Iones , Compuestos de Magnesio , Compuestos de Silicona
11.
J Hazard Mater ; 415: 124907, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34088169

RESUMEN

Nanoparticle-pollution has associated severe negative effects on crop productivity. Hence, methods are needed to alleviate nano-toxicity in crop plants. The present study aims to evaluate if the exogenous hydrogen sulfide (H2S) application in combination with silicon (Si) could palliate the harmful effects of copper oxide nanoparticles (CuO NPs). Fifteen day-old rice (Oryza sativa L.) seedlings were used as a model plant. The results indicate that simultaneous exogenous addition of 10 µM Si and 100 µM NaHS (as an H2S donor) provided tolerance and enhanced defence mechanism of the rice seedlings against 100 µM CuO NPs. Thus, it was observed in terms of their growth, photosynthetic pigments, antioxidant enzyme activities, the content of non-enzymatic components, chlorophyll fluorescence and up-regulation of antioxidant genes. Si and NaHS stimulated gene expression of silicon (Lsi1 and Lsi2) and auxin (PIN5 and PIN10) transporters. Taken together, data indicate that H2S underpins the beneficial Si effects in rice seedlings against the oxidative stress triggers by CuO NPs, and stimulation of enzymatic components of the ascorbate-glutathione cycle being the main factor for the beneficial effects triggered by the couple of Si and H2S. Therefore, it could be concluded that the simultaneous application of Si and H2S promote the resilience of the rice seedlings against the oxidative stress induced by CuO NPs.


Asunto(s)
Sulfuro de Hidrógeno , Nanopartículas , Oryza , Cobre/toxicidad , Sulfuro de Hidrógeno/toxicidad , Nanopartículas/toxicidad , Óxidos , Plantones , Silicio/toxicidad
12.
Int J Mol Sci ; 22(11)2021 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-34071094

RESUMEN

Three main approaches are used to combat severe viral respiratory infections. The first is preemptive vaccination that blocks infection. Weakened or dead viral particles, as well as genetic constructs carrying viral proteins or information about them, are used as an antigen. However, the viral genome is very evolutionary labile and changes continuously. Second, chemical agents are used during infection and inhibit the function of a number of viral proteins. However, these drugs lose their effectiveness because the virus can rapidly acquire resistance to them. The third is the search for points in the host metabolism the effect on which would suppress the replication of the virus but would not have a significant effect on the metabolism of the host. Here, we consider the possibility of using the copper metabolic system as a target to reduce the severity of influenza infection. This is facilitated by the fact that, in mammals, copper status can be rapidly reduced by silver nanoparticles and restored after their cancellation.


Asunto(s)
Cobre/metabolismo , Virus de la Influenza A/fisiología , Gripe Humana/metabolismo , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Ceruloplasmina/fisiología , Proteínas Transportadoras de Cobre/metabolismo , ATPasas Transportadoras de Cobre/fisiología , Farmacorresistencia Viral , Interacciones Huésped-Patógeno , Humanos , Vacunas contra la Influenza , Gripe Humana/tratamiento farmacológico , Gripe Humana/prevención & control , Gripe Humana/virología , Mamíferos/metabolismo , Nanopartículas del Metal/uso terapéutico , Chaperonas Moleculares/metabolismo , Proteínas PrPC/fisiología , ARN Viral/fisiología , Plata/uso terapéutico , Superóxido Dismutasa-1/fisiología , Proteínas Virales/fisiología , Replicación Viral
13.
Eur Rev Med Pharmacol Sci ; 25(10): 3772-3790, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34109586

RESUMEN

Multiple epidemiological studies have suggested that industrialization and progressive urbanization should be considered one of the main factors responsible for the rising of atherosclerosis in the developing world. In this scenario, the role of trace metals in the insurgence and progression of atherosclerosis has not been clarified yet. In this paper, the specific role of selected trace elements (magnesium, zinc, selenium, iron, copper, phosphorus, and calcium) is described by focusing on the atherosclerotic prevention and pathogenesis plaque. For each element, the following data are reported: daily intake, serum levels, intra/extracellular distribution, major roles in physiology, main effects of high and low levels, specific roles in atherosclerosis, possible interactions with other trace elements, and possible influences on plaque development. For each trace element, the correlations between its levels and clinical severity and outcome of COVID-19 are discussed. Moreover, the role of matrix metalloproteinases, a family of zinc-dependent endopeptidases, as a new medical therapeutical approach to atherosclerosis is discussed. Data suggest that trace element status may influence both atherosclerosis insurgence and plaque evolution toward a stable or an unstable status. However, significant variability in the action of these traces is evident: some - including magnesium, zinc, and selenium - may have a protective role, whereas others, including iron and copper, probably have a multi-faceted and more complex role in the pathogenesis of the atherosclerotic plaque. Finally, calcium and phosphorus are implicated in the calcification of atherosclerotic plaques and in the progression of the plaque toward rupture and severe clinical complications. In particular, the role of calcium is debated. Focusing on the COVID-19 pandemia, optimized magnesium and zinc levels are indicated as important protective tools against a severe clinical course of the disease, often related to the ability of SARS-CoV-2 to cause a systemic inflammatory response, able to transform a stable plaque into an unstable one, with severe clinical complications.


Asunto(s)
Aterosclerosis/patología , Oligoelementos/metabolismo , Aterosclerosis/metabolismo , COVID-19/patología , COVID-19/virología , Calcio/sangre , Calcio/metabolismo , Cobre/sangre , Cobre/metabolismo , Humanos , Hierro/sangre , Hierro/metabolismo , Magnesio/sangre , Magnesio/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Fósforo/sangre , Fósforo/metabolismo , Riesgo , SARS-CoV-2/aislamiento & purificación , Selenio/sangre , Selenio/metabolismo , Índice de Severidad de la Enfermedad , Oligoelementos/sangre , Zinc/sangre , Zinc/metabolismo
14.
Chemosphere ; 278: 130408, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34126676

RESUMEN

A novel electrode composed of Cu nanosheets constructed from nanoparticles was synthesized by in situ electrochemical derivation from the metal-organic framework (MOF) HKUST-1. The prepared derivative electrode (HE-Cu) exhibited higher Faradaic efficiency (FE, 56.0%) of electrochemical CO2 reduction (CO2R) compared with that of pristine Cu foil (p-Cu, 32.3%) at an overpotential of -1.03 V vs. a reversible hydrogen electrode (RHE). HE-Cu also exhibited lower onset potential of CO2R as well as inhibiting the H2 evolution reaction. Electrochemical measurements revealed that HE-Cu exhibited higher CO2 adsorption (1.58-fold) and a larger electrochemical active surface area (1.24-fold) compared with p-Cu. Physicochemical characterization and Tafel analysis showed that stepped Cu (211) surfaces, (200) facets and Cu edge atoms on HE-Cu contributed significantly to the enhanced CO2R activity and/or HCOOH and/or C2 product selectivity. The FEs of HCOOH and C2 products for HE-Cu increased 1.57-fold and 10.6-fold at an overpotential of -1.19 V vs. RHE compared with p-Cu. Although CH4 was produced on p-Cu, its formation was totally suppressed on HE-Cu due to the increase of edge sites and (200) facets. Our study demonstrates that electroreduction of MOFs is a promising method to prepare novel and stable electrochemical catalysts with unique surface structures. The fabricated derivative electrode not only promoted electrochemical CO2R activity but also exhibited high C2 product selectivity.


Asunto(s)
Estructuras Metalorgánicas , Dióxido de Carbono , Cobre , Técnicas Electroquímicas , Oxidación-Reducción
15.
Chemosphere ; 278: 130426, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34126679

RESUMEN

A reduced graphene oxide-copper sulfide-zinc sulfide (rGO-CuS-ZnS) hybrid nanocomposite was synthesized using a surfactant-free in-situ microwave technique. The in-situ microwave method was used to prepare 1-D ZnS nanorods and CuS nanoparticles decorated into the rGO nanosheets. The prepared hybrid nanocomposite catalysts were analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, elemental mapping analysis, and X-ray photoelectron spectroscopy. The effectiveness of the synthesized rGO-CuS-ZnS hybrid nanocomposite (rGO-CZS HBNC) was estimated using an innovative cathode catalyst in microbial fuel cell (MFC). MFCs were fabricated differently such as SL (single-layer), DL (double-layer), and TL (triple-layer) loading. Followed using cyclic voltammetry and impedance analyses, the electrochemical evaluation of the prepared MFCs was evaluated. Among the fabricated MFCs, the DL MFCs with rGO-CuS-ZnS cathode catalyst displayed higher power density (1692 ± 15 mW/m2) and OCP (761 ± 9 mV) than the other catalysts loadings, such as SL and TL. rGO-CZS HBNC are potential cathode materials for MFC applications.


Asunto(s)
Fuentes de Energía Bioeléctrica , Nanocompuestos , Cobre , Electrodos , Grafito , Microondas , Sulfuros , Compuestos de Zinc
16.
J Plant Physiol ; 261: 153434, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34020275

RESUMEN

The commonly used Arabidopsis thaliana natural accessions Columbia (Col-0) and Wassilewskija (Ws) are known to differ in their metal sensitivity, with Col-0 being more sensitive to copper (Cu) and cadmium (Cd) than Ws. As both Cu and Cd are known to affect Cu homeostasis, it was investigated whether this process is part of an accession-specific mechanism underlying their difference in metal sensitivity. As roots are the first contact point during metal exposure, responses were compared between roots of both accessions of hydroponically grown plants exposed to excess Cu or Cd for 24 and 72 h. Root Cu levels increased in both accessions under Cu and Cd exposure. However, under Cu exposure, the downregulation of Cu transporter (COPT) genes in combination with a more pronounced upregulation of metallothionein gene MT2b indicated that Ws plants coped better with the elevated Cu concentrations. The Cd-induced disturbance in Cu homeostasis was more efficiently counteracted in roots of Ws plants than in Col-0 plants. This was indicated by a higher upregulation of the SPL7-mediated pathway, crucial in the regulation of the Cu homeostasis response. In conclusion, maintaining the Cu homeostasis response in roots is key to accession-specific differences in Cu and Cd sensitivity.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cadmio/metabolismo , Cobre/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Homeostasis , Raíces de Plantas/genética , Raíces de Plantas/metabolismo
17.
J Hazard Mater ; 412: 125340, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-33951882

RESUMEN

Plants can cope with stressful conditions by indirectly regulating root-associated microbial structures. However, the recruitment strategies of the root-associated microbiome in combined organic and inorganic contaminated soils are not well known, especially for common agricultural crops. In this study, we performed greenhouse experiments to investigate the interactive effects of joint copper (Cu) and phenanthrene (PHE) pollution on wheat growth and microbial detoxication processes. Results show that heavy metals did not affect PHE dissipation in the rhizosphere but significantly enhanced the accumulation of PHE in the endosphere. In contrast, the addition of PHE did not influence the absorption of Cu by wheat roots. Cu was the primary factor affecting the variation of microbial communities in cocontaminated treatments among each rhizocompartment while the interactive effects of combined pollutants were only detected in unplanted bulk soil. Microbes are known to degrade polycyclic aromatic hydrocarbons and tolerant heavy metal stress e.g. Novosphingobium, Sphingomonas, Sphingobium and Pseudomonas enriched in the contaminated treatments. Our results provide an integrated understanding of the synthetic effects of combined pollutants on the root-microbial assemblage process in plant-soil systems and offer useful information on the selection of effective bioremediating root-associated microbes for the application of self-remediation by common crops.


Asunto(s)
Microbiota , Fenantrenos , Contaminantes del Suelo , Biodegradación Ambiental , Cobre/análisis , Cobre/toxicidad , Fenantrenos/análisis , Fenantrenos/toxicidad , Raíces de Plantas/química , Suelo , Microbiología del Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Triticum
18.
J Nanosci Nanotechnol ; 21(11): 5486-5492, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33980358

RESUMEN

As everyone knows, bacterial infectious diseases are serious hazards to human health in the world. Despite performing many methods towards the bacterial pollution, containing many detection and sterilization techniques, there is still a lack of effective means. Herein, a novel copper modified titanium (Cu@TiO2) nanocomposites were resoundingly synthesized via the well-known sol-gel process, which revealed a significant antibacterial activity under the illumination of sunlight. The XRD, Raman spectroscopy and TEM images showed that the Cu@TiO2 nanocomposites with a globular shape are anatase phase, Moreover, low temperature physical adsorption test and UV- visible spectrum indicate Cu0.01 @TiO2 owns a supernal specific area (80 m²/g) and the high visible light absorbing ability. Furthermore, the novel Cu@TiO2 nanocomposites showed an unprecedented photocatalytic capacity towards Escherichia Coli (E. coli) bacteria. In vitro, Cu@TiO2 nanocomposites can kill almost 98.7% E. coli under 60 min simulated solar light irradiation than that of TiO 2(31.3 %). This study suggests that the Cu@TiO2 will be as a potential material for ameliorating antibiotic-resistant bacteria in food detection.


Asunto(s)
Nanocompuestos , Titanio , Catálisis , Cobre/farmacología , Escherichia coli , Humanos , Luz , Titanio/farmacología
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 259: 119887, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-33971442

RESUMEN

In this work, the fluorescent copper nanoclusters (Cu NCs) were firstly adopted to detect luteolin with excellent performance. The blue-emitting Cu NCs was successfully prepared through a facile one-pot approach by protection of tannic acid (TA) and chemical reduction of ascorbic acid (AA). The water-soluble nanoclusters possessed uniform size and displayed good stability. The TA-Cu NCs showed maximum luminescence at 434 nm when excited at 366 nm. Based on the static quenching and inner filter effect (IFE) mechanism, the TA-Cu NCs was efficiently and selectively quenched by luteolin. The detection limit was 0.12 µM and linear relationship existed in the range of 0.2-100 µM. Moreover, the TA-Cu NCs probe was successfully employed to detect luteolin in bovine serum samples with satisfactory recoveries. This novel platform was expected to expand the possible detection method based on fluorescence properties.


Asunto(s)
Cobre , Luteolina , Animales , Bovinos , Fluorescencia , Colorantes Fluorescentes , Espectrometría de Fluorescencia , Taninos
20.
J Hazard Mater ; 412: 125216, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-33951861

RESUMEN

Acid mine drainage-affected environments are interesting microbial niches for the isolation of metal-resistant microorganisms. In this sense, the aim of the present work is to isolate and characterize metal-resistant microorganisms from sediments of an abandoned gold mine located in San Luis (Argentina). For these purposes, the metal removal capacity and the microelemental composition of the biomass exposed to metals were evaluated. Likewise, proteomic techniques were applied to understand the removal and resistance mechanisms. Fusarium tricinctum M6 was isolated and identified as tolerant to Cu(II), Fe(II) and Cr(VI). When faced with 40 µg mL-1 Cu(II), the growth was affected by 60% and the removal capacity was 30-35%. Copper was found uniformly distributed in the biomass (5.23% w/w) and variations in the proportion of other biomass constituent elements were detected. When exposed to Cu(II), F. tricinctum M6 showed differential expression of intra and extracellular proteins involved in different metabolic processes. A large number of proteins with metal ion binding sites were detected both at intra and extracellular levels. The results obtained in the present work indicated bioadsorption of the metal on the cell surface and an important readjustment of the protein expression to counteract the stress produced by Cu(II).


Asunto(s)
Cobre , Fusarium , Argentina , Cobre/toxicidad , Proteómica
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