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1.
J Hazard Mater ; 421: 126737, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34388922

RESUMO

Cupriavidus metallidurans is a model bacterium to study molecular metal resistance mechanisms and its use for the bioremediation of several metals has been shown. However, its mechanisms for radionuclide resistance are unexplored. We investigated the interaction with uranium and associated cellular response to uranium for Cupriavidus metallidurans NA4. Strain NA4 actively captured 98 ± 1% of the uranium in its biomass after growing 24 h in the presence of 100 µM uranyl nitrate. TEM HAADF-EDX microscopy confirmed intracellular uranium-phosphate precipitates that were mainly associated with polyhydroxybutyrate. Furthermore, whole transcriptome sequencing indicated a complex transcriptional response with upregulation of genes encoding general stress-related proteins and several genes involved in metal resistance. More in particular, gene clusters known to be involved in copper and silver resistance were differentially expressed. This study provides further insights into bacterial interactions with and their response to uranium. Our results could be promising for uranium bioremediation purposes with the multi-metal resistant bacterium C. metallidurans NA4.


Assuntos
Cupriavidus , Urânio , Cobre/toxicidade , Cupriavidus/genética , Fosfatos , Urânio/toxicidade
2.
J Hazard Mater ; 421: 126688, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34315634

RESUMO

Improper disposal of copper mining wastes can threaten the ecosystem and human health due to the high levels of potentially toxic elements released into the environment. The objective of this study was to determine the properties of Cu mining wastes generated in the eastern Amazon and their potential risks to environment and human health. Samples of forest soil and artisanal/industrial Cu mining wastes were collected and subjected to characterization of properties and pseudo-total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn, in addition to chemical fractionation of Cu. The pH ranged from near neutrality to alkaline. Pseudo-total concentrations of Cu were high in all wastes, mainly in the artisanal rock waste, with 19,034 mg kg-1, of which 61% is concentrated in the most reactive fractions. Pollution indices indicated that the wastes are highly contaminated by Cu and moderately contaminated by Cr and Ni. However, only the artisanal rock waste is associated with environmental risk. Non-carcinogenic and carcinogenic human health risks were detected, especially from exposure to Cr in the artisanal rock waste. Prevention actions and monitoring of the artisanal mining area are necessary to avoid impacts to the local population.


Assuntos
Metais Pesados , Poluentes do Solo , Cobre/toxicidade , Ecossistema , Monitoramento Ambiental , Humanos , Resíduos Industriais/análise , Metais Pesados/análise , Mineração , Medição de Risco , Poluentes do Solo/análise
3.
J Hazard Mater ; 421: 126728, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34339990

RESUMO

The increasing release of nanomaterials has attracted significant concerns for human and environmental health. Similarly, the dissemination of antimicrobial resistance (AMR) is a global health crisis affecting approximately 700,000 people a year. However, a knowledge gap persists between the spread of AMR and nanomaterials. This study aims to fill this gap by investigating whether and how nanomaterials could directly facilitate the dissemination of AMR through horizontal gene transfer. Our results show that commonly-used nanoparticles (NPs) (Ag, CuO and ZnO NPs) and their ion forms (Ag+, Cu2+ and Zn2+) at realistic concentrations within aquatic environments can significantly promote the transformation of extracellular antibiotic resistance genes in Acinetobacter baylyi ADP1 by a factor of 11.0-folds, which is comparable to the effects of antibiotics. The enhanced transformation by Ag NPs/Ag+ and CuO NPs/Cu2+ was primarily associated with the overproduction of reactive oxygen species and cell membrane damage. ZnO NPs/Zn2+ might increase the natural transformation rate by stimulating the stress response and ATP synthesis. All tested NPs/ions resulted in upregulating the competence and SOS response-associated genes. These findings highlight a new concern that nanomaterials can speed up the spread of AMR, which should not be ignored when assessing the holistic risk of nanomaterials.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Acinetobacter , Antibacterianos/toxicidade , Cobre/toxicidade , Resistência Microbiana a Medicamentos/genética , Humanos , Íons , Nanopartículas Metálicas/toxicidade
4.
Food Chem ; 368: 130811, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34399177

RESUMO

Since excessive use of synthetic dyes has negative effects on human health, their determination in foodstuff is necessary. A sensitive sensor was developed based on copper BTC metal-organic framework (Cu-BTC MOF) and 1-ethyl-3-methylimidazolium chloride as an ionic liquid (IL) in an attempt to modify the carbon paste electrode and to improve the active surface area and electric conductivity so that electron transfer is faster for electro analysis. For the first time, high sensitivity, excellent conductivity, and appropriate selectivity of the electrochemical sensor have been evaluated as a new study for simultaneous determination of tartrazine, patent blue V, acid violet 7 and ponceau 4R. Excellent sensing performance of the proposed electrode was confirmed for patent blue V as an outstanding sensor, according to the low limit of detection of 0.07 µM, with a wide linear concentration range of 0.08 to 900 µM and reasonable recovery. In order to characterize the electrochemical behavior of electrode, cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy are used. Various techniques such as scanning electron microscopy (SEM) with energy dispersive X-Ray analysis (EDX), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) are employed to verify the structure of copper BTC metal-organic framework. The results revealed close packing of hierarchically porous nanoparticles and crystal structure of Cu-BTC MOF, with the edge of each particle around 20-37 nm. The analytical performance of the suggested electrochemical sensor is acceptable in foodstuffs such as jellies, condiments, soft drinks, and candies.


Assuntos
Líquidos Iônicos , Estruturas Metalorgânicas , Compostos Azo , Cobre , Técnicas Eletroquímicas , Eletroquímica , Eletrodos , Humanos , Naftalenossulfonatos , Corantes de Rosanilina , Tartrazina
5.
Talanta ; 236: 122835, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635225

RESUMO

Enrofloxacin (ENR) is a broad-spectrum fungicide that has been largely applied in pharmacy and animal-specific medicine. In this paper, a simple, novel and highly sensitive molecularly imprinted electrochemiluminescence (MIP-ECL) sensor based on mercaptopropionic acid-functionalized copper nanoclusters (MPA-Cu NCs) was developed to selectively detect enrofloxacin (ENR). MPA-Cu NCs prepared by a one-step method were used to modify the glassy carbon electrode. A molecularly imprinted polymer film containing the cavity was constructed after electropolymerization and elution. Under optimized conditions, the MIP-ECL sensor could detect ENR in the range of 0.1 nM-1 µM (R2 = 0.9863) with a low limit of detection of 27 pM, and the recovery rates of ENR in biological and lake water samples were 88.20-105.0%. The MIP-ECL sensor provided path to improve the stability issues of Cu NCs, which might open promising avenues to develop new ECL systems for biological analysis and environmental water monitoring.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Cobre , Eletrodos , Enrofloxacina
6.
Talanta ; 236: 122865, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635247

RESUMO

A sandwich-type electrochemical immunosensor was designed utilizing ferrocene-functionalized cuprous oxide superparticles (Au/Fc@CuxO SPs) as the signal label and graphene supported by hollow carbon balls (HCNs-GR) as the substrate. The CuxO SPs possess a superparticle structure with synergistic properties of isotropy and promising catalytic activity. Ferrocene (Fc) was deposited on the CuxO SPs to act as the electronic transmission medium. The Au/Fc@CuxO SPs played a pivotal role in improving the sensitivity of the immunosensor. The graphene supported by hollow carbon balls (HCNs-GR) was used to modify the electrode surface. The embedding of hollow carbon nanospheres (HCNs) reduced the decrease of the effective surface area caused by the stacking of graphene nanotubes. Meanwhile, the load of carbon balls further increases the surface area of graphene, enabled HCNs-GR to immobilize antibodies more effectively, improved the sensitivity of the immunosensor. The proposed immunosensor showed a linear range from 500 fg/mL to 100 ng/mL, with the detection limit to 25.7 fg/mL.


Assuntos
Técnicas Biossensoriais , Cobre , Técnicas Eletroquímicas , Imunoensaio , Metalocenos
7.
Food Chem ; 367: 130659, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343800

RESUMO

This study presents a sensitive approach for electrochemical determination of 5-hydroxymethylfurfural (5-HMF) in food. The electrochemical sensor was fabricated on a copper electrode (CuE) modified with co-electrodeposited Cu-Ni bimetallic particles. This sensor, fabricated by 30 cycles of cyclic voltametric scanning with a scan rate of 50 mV s-1, exhibits good electrocatalytic ability to 5-HMF oxidation. Under the optimal conditions, linear scan voltammetry (LSV) and chronoamperometry were conducted for the determination of 5-HMF. The results of LSV show that a linear dependency within the 0.4-10 mM range with a detection limit (LOD) of 3.51 µM (S/N = 3) was achieved, while a linear range in 1 × 10-4-11 mM with a LOD of 0.043 µM (S/N = 3) was obtained by chronoamperometric measurement. The electrochemical sensor was finally applied in determination of 5-HMF in various foods, and the reliability and accuracy of the method were assessed by adopting an UV method as a standard method. Results show that the concentrations of 5-HMF in real samples are close to those measured by the standard method. In addition, standard addition method was further performed to evaluate the accuracy of our approach. The recoveries ranged from 90.0% to 110.0% are calculated, demonstrating good accuracy of the electrochemical sensor.


Assuntos
Cobre , Técnicas Eletroquímicas , Eletrodos , Furaldeído/análogos & derivados , Limite de Detecção , Reprodutibilidade dos Testes
8.
Food Chem ; 367: 130669, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34365252

RESUMO

Analysis of digital images by smartphone was used for copper quantification in sugarcane spirit (cachaça) samples through the formation of blue complex between copper and cuprizone. An experimental design was carried out to evaluate the best complexation reaction conditions. Moreover, different image acquisition procedures (external camera coupled to a smartphone or the smartphone camera) with different regions of interest sizes, distances in image acquisition, and concentration ranges of the calibration curve and the influence of processing the curve in univariate and multivariate modes, by PLS, were evaluated. The results obtained in three real samples and two spikes were compared with those of UV-Vis spectrophotometry, used as a reference method, and they show the potential of the proposed method for the accurate determination of copper. When compared to traditional techniques, the proposed method has the advantages of portability and low cost in addition to requiring a smaller amount of reagents.


Assuntos
Cobre , Saccharum , Grão Comestível , Projetos de Pesquisa , Smartphone
9.
Food Chem ; 367: 130748, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34375894

RESUMO

The development of a collaborative study as a requirement for the preparation of a laboratory reference material candidate is reported in this paper. The evaluation was performed by 13 laboratories invited to quantify the calcium, potassium, magnesium, phosphorus, copper, iron, manganese and zinc; 8 of them presented results for all the analytes under investigation. The data were statistically analyzed by applying the z-score robust technique as recommended by ISO Guide 35. For the potassium element, laboratories 4 and 13 presented questionable results. Laboratory 5 proved to be unsatisfactory for calcium and zinc. ANOVA-PCA and DD-SIMCA were also applied to evaluate stability and interlaboratory studies results, respectively. It has been demonstrated that multivariate data analysis can be successfully applied as an alternative method to the recommendations made by ISO 13528 and ISO Guide 35 with defined confidence intervals.


Assuntos
Laboratórios , Zea mays , Análise de Variância , Cálcio , Cobre , Farinha , Magnésio
10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(5): 799-806, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34622596

RESUMO

Objective: To explore the preparation method of copper (Cu)-doped hydroxyapatite (HA) microspheres loaded with vancomycin (Van), and evaluate their antibacterial and osteogenic effects in vitro. Methods: The Cu doped HA microspheres (Cu-HA) with molar doping ratios of 1%, 5%, 10%, and 20% were prepared by hydrothermal synthesis. The microscopic morphology changes were observe with scanning electron microscope. X-ray diffractometer (XRD) was used to study the phase composition and analyze the crystallinity of the sample. Cu-HA with a molar doping ratio of 10% was selected for analysis of the elemental composition of the sample with energy dispersive X-ray spectroscopy (EDS), and was then coated with polydopamine (PDA) as the medium to prepare Cu-HA-PDA. XRD and Fourier infrared spectrometer were used to examine the coating effect of the sample. Van was load on Cu-HA-PDA to prepare Cu-HA-PDA-Van. HA, Cu-HA, HA-PDA, and Cu-HA-PDA-Van were added to α medium at 10 mg/mL to prepare different groups of extract solutions.The main components of the extract solutions were examined, and the Van concentration was checked. We examined the toxic effect of material extract solutions on osteogenic precursor cells and the proliferation and differentiation of bone marrow mesenchymal stem cells, and checked the expression of osteocalcin ( OCN), runt-related transcription factor 2 ( RUNX-2), and alkaline phosphatase ( ALP), the osteogenic related genes. Sterilized HA, Cu-HA, HA-PDA, Cu-HA-PDA, Cu-HA-DPA-Van microsphere materials were prepared, and the colony counting method was used to evaluate the antibacterial effect of the materials for Staphylococcus aureus. Results: Various types of Cu-doped HA (Cu-HA) were successfully synthesized. As the proportion of Cu increased, the morphology gradually changed from being strip or belt-shaped to a uniform spherical shape. Cu-HA of 10% molar doping ratio showed a clearly microspherical shape and a petal-like porous micro-nano morphology on the surface. EDS and XRD analyses showed that the main structure of the material was still made up of hydroxyapatite crystals and Cu was successfully doped with HA. The infrared spectrometer showed that the PDA was successfully coated on the surface of the material. Examination of the main components of the extract solution once again verified that the Cu element had successfully entered and replaced part of the Ca element in the HA. The 10 mg/mL Cu-HA-PDA-Van extract solution contained 0.27 mg/mL of Van. In vitro cell experiments and bone-formation-related gene testing showed that Cu-HA-Van had good biological activity and promoted bone differentiation. The minimum inhibitory concentration (MIC) of Cu-HA-PDA-Van microspheres was 16 µg/mL. Compared with Cu-HA, HA-PDA and pure HA, Cu-HA-Van microspheres had significant and long-lasting antibacterial effects. Conclusion: Cu element was used to control the microscopic morphology of HA, and the Cu-HA-PDA-Van microspheres prepared by successfully coating of PDA and loading of Van had good antibacterial properties and biological activity.


Assuntos
Antibacterianos , Durapatita , Antibacterianos/farmacologia , Cobre , Durapatita/farmacologia , Microesferas , Osteogênese
11.
J Coll Physicians Surg Pak ; 31(10): 1231-1233, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34601848

RESUMO

Wilson's disease (WD) is an autosomal recessive disorder that affects copper metabolism. Mutations of the ATP7B gene have been found to be strongly associated with a risk of developing WD; and at present, more than 500 mutations have been reported in WD patients. The Arg778Leu and Arg952Lys mutations in exons 8 and 12, respectively, are highly prevalent in the Chinese population. However, early detection of WD is difficult due to the extreme variations in mutations of ATP7B, and the lack of specific clinical symptoms during the early stages of the disease. Meanwhile, the early stage of occult hepatitis B infection lacks typical clinical manifestations, which easily leads to it being misdiagnosed as liver cirrhosis. We report a new pathogenic exon 19 mutation of ATP7B,which can potentially contribute to the early genetic diagnosis and prompt treatment of WD. Key Words: Wilson's disease, Gene mutation, ATP7B, Cirrhosis, Occult hepatitis B infection.


Assuntos
ATPases Transportadoras de Cobre/genética , Hepatite B Crônica , Degeneração Hepatolenticular , Cobre , Vírus da Hepatite B/genética , Degeneração Hepatolenticular/diagnóstico , Degeneração Hepatolenticular/genética , Humanos , Cirrose Hepática/genética , Mutação
12.
Sensors (Basel) ; 21(19)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34640857

RESUMO

A rapid and high-throughput fluorescence detection method for zearalenone (ZEN) based on a CuO nanoparticle (NP)-assisted signal amplification immunosensor was developed using an automated sample pretreatment and signal conversion system. CuO NPs with high stability and biocompatibility were used as carriers to immobilize anti-ZEN antibodies. The obtained CuO NP-anti-ZEN can maintain the ability to recognize target toxins and act as both a signal source and carrier to achieve signal conversion using automated equipment. In this process, target toxin detection is indirectly transformed to Cu2+ detection because of the large number of Cu2+ ions released from CuO NPs under acidic conditions. Finally, a simple and high-throughput fluorescence assay based on a fluorescent tripeptide molecule was employed to detect Cu2+, using a multifunctional microporous plate detector. A good linear relationship was observed between the fluorescence signal and the logarithm of ZEN concentration in the range of 16.0-1600.0 µg/kg. Additionally, excellent accuracy with a high recovery yield of 99.2-104.9% was obtained, which was concordant with the results obtained from LC-MS/MS of naturally contaminated samples. The CuO NP-based assay is a powerful and efficient screening tool for ZEN detection and can easily be modified to detect other mycotoxins.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Zearalenona , Cromatografia Líquida , Cobre , Imunoensaio , Óxidos , Espectrometria de Massas em Tandem , Zearalenona/análise
13.
Microbiome ; 9(1): 201, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641951

RESUMO

BACKGROUND: Although considered as holobionts, macroalgae and their surface microbiota share intimate interactions that are still poorly understood. Little is known on the effect of environmental parameters on the close relationships between the host and its surface-associated microbiota, and even more in a context of coastal pollutions. Therefore, the main objective of this study was to decipher the impact of local environmental parameters, especially trace metal concentrations, on an algal holobiont dynamics using the Phaeophyta Taonia atomaria as a model. Through a multidisciplinary multi-omics approach combining metabarcoding and untargeted LC-MS-based metabolomics, the epibacterial communities and the surface metabolome of T. atomaria were monitored along a spatio-temporal gradient in the bay of Toulon (Northwestern Mediterranean coast) and its surrounding. Indeed, this geographical area displays a well-described trace metal gradient particularly relevant to investigate the effect of such pollutants on marine organisms. RESULTS: Epibacterial communities of T. atomaria exhibited a high specificity whatever the five environmentally contrasted collecting sites investigated on the NW Mediterranean coast. By integrating metabarcoding and metabolomics analyses, the holobiont dynamics varied as a whole. During the occurrence period of T. atomaria, epibacterial densities and α-diversity increased while the relative proportion of core communities decreased. Pioneer bacterial colonizers constituted a large part of the specific and core taxa, and their decrease might be linked to biofilm maturation through time. Then, the temporal increase of the Roseobacter was proposed to result from the higher temperature conditions, but also the increased production of dimethylsulfoniopropionate (DMSP) at the algal surface which could constitute of the source of carbon and sulfur for the catabolism pathways of these taxa. Finally, as a major result of this study, copper concentration constituted a key factor shaping the holobiont system. Thus, the higher expression of carotenoids suggested an oxidative stress which might result from an adaptation of the algal surface metabolome to high copper levels. In turn, this change in the surface metabolome composition could result in the selection of particular epibacterial taxa. CONCLUSION: We showed that associated epibacterial communities were highly specific to the algal host and that the holobiont dynamics varied as a whole. While temperature increase was confirmed to be one of the main parameters associated to Taonia dynamics, the originality of this study was highlighting copper-stress as a major driver of seaweed-epibacterial interactions. In a context of global change, this study brought new insights on the dynamics of a Mediterranean algal holobiont submitted to heavy anthropic pressures. Video abstract.


Assuntos
Microbiota , Alga Marinha , Bactérias/genética , Cobre , Metaboloma , Microbiota/genética
14.
Environ Monit Assess ; 193(11): 705, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34623520

RESUMO

Trace metals are vital to primary productivity and play an essential role as main components in regulating oceanic biogeochemical cycles. Dissolved and particulate trace metals within the water column may vary due to primary production, temperature, and nutrient changes, factors that may also vary spatially and temporally. Furthermore, assessment of trace metals mainly relies on in situ observation, and so wide-area investigation of trace-metal concentration may be challenging and subject to technical constraints. A specific approach is therefore necessary that combines biogeochemical proxies, satellite data, and trace-metal linear correlation. This study aims to assess the potential spatio-temporal variability of sea surface cadmium (Cd) and copper (Cu) concentrations in Indonesian seas and surrounding areas. The correlations of Cd and Cu concentrations with primary production and nutrient data were used to convert hindcast satellite data into estimates of the metals' concentrations. The potential variability of trace metals can be determined by overlaying both data. Indonesia's Fisheries Management Areas (FMAs) were used for data clustering and analysis. The results show that Cd and Cu trace metals have similar distribution patterns throughout the year. However, dissolved Cu has a more diverse coverage area than dissolved Cd, including within the Halmahera, Seram, and Maluku Seas (FMAs 716 and 717), the Makassar Strait (FMA 717), and the Java-Sumatra upwelling area (FMA 573). Both Cd and Cu concentrations in the Java-Sumatra upwelling region follow the periodic upwelling pattern. Overall, both Cd and Cu show a declining trend in concentration from 2012 to 2019. It is estimated that dissolved Cd concentration declined from 1500-2000 pmol/kg in 2012 to 1000-1500 pmol/kg in 2019 for all locations. Dissolved Cu concentration decreased from 30-35 nmol/kg in 2012 to 25-30 nmol/kg in 2019. Estimated dissolved Cd and Cu follow the linear functions of silicate (SiO4), nitrate (NO3), and primary productivity. The fluctuation of anthropogenic activities and global warming are likely to indirectly impact the decline in metal concentrations by affecting nutrients and primary productivity.


Assuntos
Metais Pesados , Oligoelementos , Cádmio/análise , Cobre/análise , Monitoramento Ambiental , Metais Pesados/análise , Oligoelementos/análise
15.
Georgian Med News ; (318): 139-142, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34628395

RESUMO

Structural organization of serum albumins - the most abundant globular proteins in serum plasma - gives rise to their extraordinary binding and functional capacity. Various classes of ligands, including the metal ions can be captured and transported by albumins. Metal binding to human serum albumin, HSA, that is an essential multipurpose target for the modern biomedicine, to its bovine equivalent, BSA, and other mammalian analogs have been extensively explored in the context of metabolism of essential metal ions, like Cu2+. Taking into account structural similarity of human and bovine serum albumins, the later was selected as a relevant model in laboratory studies due to its low cost and wide availability. In the present work metal binding properties of BSA with copper ions (Cu2+) were explored using combined voltammetric and thermodynamic examinations. According to voltammetric data, addition of equal amount of BSA (1.8x10-3)M to the solution (0.2 M KCl) containing (1.8x 10-3) M CuCl2 results that two pairs of redox peaks belonging to the Cu2+ /Cu+ (E0 = 0,16 V) and Cu+/Cu0 (E0 = -0.2 V) electronic transformations disappear and a new weak single reductive peak, at Epk=-0,55V attributable to the Cu2+/Cu+ transition is shown. BSA- Cu2+ complex formation is presumably responsible for this dramatic shift of Cu2+ reduction process to much more negative potential. The chelating environment of "N-terminal" sequence of: Asp-Thr-His- of BSA, assisted by direct participation of the sulfuric group of a Cys-34 residue, is presumably responsible for the entrapment and "locking" the copper ion, in an "abnormal", redox inactive condition (showing virtually no voltammetric activity). Our DSC data confirmed the complex formation process in the solutions containing the equal (1.8x10-3) M concentrations of both, BSA and CuCl2 and clearly shows small but distinct conformational stabilization with respect of two thermodynamic parameters, the melting temperature and melting enthalpy.


Assuntos
Cobre , Albumina Sérica , Animais , Bovinos , Humanos , Metais , Soroalbumina Bovina , Termodinâmica
16.
BMC Gastroenterol ; 21(1): 384, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34666712

RESUMO

BACKGROUND: Wilson disease (WD) is a rare genetic disorder of copper metabolism. Differences in copper tissue accumulation lead to various clinical manifestations, including some atypical presentations. The complex clinical features of WD make diagnosis challenging, delaying the best chance for treatment. CASE PRESENTATION: We report a case of a 26-year-old man with nephritis-range proteinuria and elevated serum creatinine. The renal pathology indicated immunoglobulin A (IgA) nephropathy and tubular injury, which was inconsistent with glomerular lesions. Cirrhosis was also detected by imaging examination. Considering both kidney injury and liver damage, WD was suspected. Based on results showing abnormal copper metabolism, corneal Kayser-Fleischer rings, and genetic disorders in the ATP7B gene, the patient was finally diagnosed with WD. After treatment with oral penicillamine, zinc sulfate and losartan, the patient showed alleviation of both WD and nephropathy after 3 years of follow-up. He maintained a good quality of daily life. CONCLUSION: This case highlights that unexplained neurological and liver symptoms in patients with IgA nephropathy can be clues for WD.


Assuntos
Glomerulonefrite por IGA , Degeneração Hepatolenticular , Adulto , Cobre , Glomerulonefrite por IGA/complicações , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/tratamento farmacológico , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/diagnóstico , Degeneração Hepatolenticular/tratamento farmacológico , Humanos , Masculino , Programas de Rastreamento
17.
Bioresour Technol ; 341: 125859, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523571

RESUMO

This study aimed to investigate the short-term response of abundant-rare genera and antibiotic resistance genes (ARGs) to azithromycin (AZM, 0.05-40 mg/L) and copper (1 mg/L) combined pollution in activated sludge nitrification system at low temperature. Nitrification was as expected inhibited in stress- and post-effects periods under AZM concentration higher than 5 mg/L. Abundant and rare taxa presented dissimilar responses based on full-scale classification. Conditionally rare or abundant taxa (CRAT) were keystone taxa. Relative abundance of ammonia-oxidizing archaea increased, and three aerobic denitrifying bacteria (Brevundimonas, Comamonas and Trichococcus) were enriched (from 9.83% to 68.91% in total). Ammonia nitrogen assimilating into Org-N and denitrification may be nitrogen pathways based on predict analysis. 29 ARGs were found with more co-occurrence patterns and high concentration of AZM (greater than 5 mg/L) caused their proliferation. Importantly, expect for some abundant taxa, rare taxa, potential pathogens and nitrogen-removal functional genera were the main potential hosts of ARGs.


Assuntos
Microbiota , Nitrificação , Antibacterianos/farmacologia , Azitromicina/farmacologia , Cobre/farmacologia , Desnitrificação , Resistência Microbiana a Medicamentos/genética , Laboratórios , Nitrogênio/análise , Esgotos , Temperatura
18.
Chem Biol Interact ; 348: 109636, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34506769

RESUMO

l-argininato copper(II) complexes have been intensively investigated in a variety of diseases due to their therapeutic potential. Here we report the results of comprehensive structural studies (ESI-MS, NIR-VIS-UV, EPR) on the complexes arising in aqueous solutions of two ternary copper(II) complexes with molecular formulas from crystal structures, [Cu(l-Arg)2(NCS)](NCS)·H2O (1) and [Cu(l-Arg)(NCS)2] (2) (l-Arg = l-arginine). Reference systems, the ternary Cu(II)/l-Arg/NCS- as well as binary Cu(II)/NCS- and Cu(II)/l-Arg, were studied in parallel in aqueous solutions by pH-potentiometric titration, EPR and VIS spectroscopy to characterize stability, structures and speciation of the formed species over the broad pH range. Comparative analysis of the obtained results showed that at a pH close to 7.0 mononuclear [Cu(l-Arg)2(NCS)]+ is the only species in water solution of 1, while equilibrium between [Cu(l-Arg)(SCN)]+ and binary [Cu(l-Arg)2]2+ was detected in water solution of 2. According to DNA binding studies, the [Cu(l-Arg)2(NCS)]+, [Cu(l-Arg)(SCN)]+ and [Cu(l-Arg)2]2+ species could be considered as strong minor groove binding agents causing, in the presence of H2O2, the involvement of ROS in plasmid damage. The human carcinoma cells (A549 cell line) were generally significantly more sensitive to cytotoxic and antiproliferative effect of compounds 1 and 2 than human normal cells. The studied compounds shown antimicrobial activity against bacteria belonging to Enterobacteriaceae family.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , DNA/metabolismo , Isotiocianatos/química , Células A549 , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Complexos de Coordenação/metabolismo , Humanos , Modelos Moleculares , Conformação Molecular , Soluções
19.
Chem Biol Interact ; 348: 109647, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34520752

RESUMO

In order to discover new therapeutically active agents a series of novel copper(II) complexes with 3,4-dihydro-2(1H)-quinoxalinones were synthesized. All complexes were characterized by IR and EPR spectroscopic techniques and examined for their cytotoxic effect on human cancer cell lines HeLa, LS174, A549 and normal fibroblasts (MRC-5). For further examination of the cytotoxic mechanisms of novel complexes, three of them were chosen for analysing their effects on the distribution of HeLa cells in the cell cycle phases. The results of the flow cytometry analysis suggest that tested complexes lead to time-dependent accumulation of the cells in S and G2/M phases. The strongest accumulation effect showed complex 2d after 48 h of incubation. Competitive experiments with ethidium bromide (EB) indicated that tested compound 2d have affinity to displace EB from the EB-DNA complex through intercalation. Also, the binding parameters values for 2d-BSA complex showed that a reversible 2d-BSA complex is formed and ligand 2d can be stored and carried by BSA.


Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , DNA/metabolismo , Quinoxalinas/química , Soroalbumina Bovina/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/metabolismo , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica , Soroalbumina Bovina/química
20.
Anal Chim Acta ; 1181: 338929, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34556217

RESUMO

The dispersed gold nanoparticles (AuNPs) have weak photothermal effect in near-infrared (NIR) region. After the addition of cysteine, the AuNPs are aggregated due to the electrostatic interaction and then exhibited strong photothermal effect. At present of copper ion (Cu2+), the cysteine was catalytically oxidized into cystine, leading to the inhibition of the aggregation of AuNPs and the photothermal effect decreased. Based on this, a simple photothermal assay can be developed for Cu2+ detection using a common thermometer as readout. The change of the temperature (ΔT) of the system has a linear relationship with Cu2+ in the range of 10-300 nM with a detection limit of 7.4 nM (S/N = 3). Furthermore, through labeling the detection antibody in immunoassay with CuO nanoparticles as the source of Cu2+, a convenient photothermal immunoassay can be developed. Carcinoembryonic antigen (CEA), an important biomarker for cancer screening, was chosen as the model target because the rise of CEA level is widely present in cancer blood serum. Under the optimized conditions, ΔT has a linear relationship with CEA concentration in the range of 3.0-48.0 ng/mL. The detection limit is 1.3 ng/mL. The proposed method had been applied to detect CEA in serum samples with good agreement with the reference method used in hospital.


Assuntos
Técnicas Biossensoriais , Antígeno Carcinoembrionário/análise , Imunoensaio , Neoplasias/diagnóstico , Cobre , Cisteína , Ouro , Humanos , Limite de Detecção , Nanopartículas Metálicas , Termômetros
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