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1.
Int J Biol Macromol ; 261(Pt 2): 129962, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316322

RESUMO

In this work, novel monoclinic tungsten oxide (WO3)-encapsulated phosphate-rich porous sodium alginate (PASA) microspherical hydrogel beads were prepared for efficient U(VI) capture. These macroporous and hollow beads were systematically characterized through XRD, FTIR, EDX-mapping, and SEM-EDS techniques. The O and P atoms in the PO and monoclinic WO3 offered inner-spherical complexation with U(VI). The in situ growth of WO3 played a significant role inside the phosphate-rich biopolymeric network to improve its chemical stability, specific surface area, adsorption capacity, and sorption rate. The phytic acid (PA) served for heteroatom doping and crosslinking. The encapsulated WO3 mass ratio was optimized in different composites, and WO3/PASA3 (the microspherical beads with a mass ratio of 30.0 % w/w) exhibited remarkable maximum sorption capacity qm (336.42 mg/g) computed through the best-fit Langmuir model (R2 ≈ 0.99) and rapid sorption equilibrium, teq (150 min). The isothermal sorption studies were conducted at different temperatures (298, 303, and 308 K) and thermodynamic parameters concluded that the process of U(VI) sorption using WO3/PASA3 is endothermic and feasible having ΔHo (8.19 kJ/mol), ΔGo (-20.75, -21.38, and - 21.86 kJ/mol) and proceeds with a minute increase in randomness ΔSo (0.09 kJ/mol.K). Tungsten oxide (WO3)-encapsulated phosphate-rich porous microspherical beads could be promising material for uranium removal.


Assuntos
Alginatos , Óxidos , Tungstênio , Urânio , Alginatos/química , Adsorção , Fosfatos , Porosidade , Termodinâmica , Cinética , Urânio/química , Concentração de Íons de Hidrogênio
2.
J Clin Hypertens (Greenwich) ; 26(2): 187-196, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38214193

RESUMO

There are limited data available regarding the connection between hypertension and heavy metal exposure. The authors intend to establish an interpretable machine learning (ML) model with high efficiency and robustness that identifies hypertension based on heavy metal exposure. Our datasets were obtained from the US National Health and Nutrition Examination Survey (NHANES, 2013-2020.3). The authors developed 5 ML models for hypertension identification by heavy metal exposure, and tested them by 10 discrimination characteristics. Further, the authors chose the optimally performing model after parameter adjustment by Genetic Algorithm (GA) for identification. Finally, in order to visualize the model's ability to make decisions, the authors used SHapley Additive exPlanation (SHAP) and Local Interpretable Model-Agnostic Explanations (LIME) algorithm to illustrate the features. The study included 19 368 participants in total. A best-performing eXtreme Gradient Boosting (XGB) with GA for hypertension identification by 16 heavy metals was selected (AUC: 0.774; 95% CI: 0.772-0.776; accuracy: 87.7%). According to SHAP values, Barium (0.02), Cadmium (0.017), Lead (0.017), Antimony (0.008), Tin (0.007), Manganese (0.006), Thallium (0.004), Tungsten (0.004) in urine, and Lead (0.048), Mercury (0.035), Selenium (0.05), Manganese (0.007) in blood positively influenced the model, while Cadmium (-0.001) in urine negatively influenced the model. Study participants' hypertension associated with heavy metal exposure was identified by an efficient, robust, and interpretable GA-XGB model with SHAP and LIME. Barium, Cadmium, Lead, Antimony, Tin, Manganese, Thallium, Tungsten in urine, and Lead, Mercury, Selenium, Manganese in blood are positively correlated with hypertension, while Cadmium in blood is negatively correlated with hypertension.


Assuntos
Compostos de Cálcio , Hipertensão , Mercúrio , Metais Pesados , Óxidos , Selênio , Humanos , Cádmio/urina , Inquéritos Nutricionais , Antimônio/urina , Manganês , Tálio/urina , Tungstênio/urina , Bário/urina , Estanho , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Metais Pesados/efeitos adversos , Metais Pesados/urina , Aprendizado de Máquina
3.
Environ Res ; 242: 117817, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043892

RESUMO

In this study, lanthanum carbonate (LC) was selected as a capping agent to examine its effectiveness in immobilizing sediment internal phosphorus (P), arsenic (As) and tungsten (W). With a 180-day incubation experiment, it was determined that LC capping efficiently reduced the concentrations of soluble reactive P (SRP), soluble As and soluble W in pore water, with the highest reduction rate of 83.39%, 56.21% and 68.52%, respectively. The primary mechanisms involved in the adsorption of P, As and W by LC were precipitation reactions and ligand exchange. Additionally, P, As and W were immobilized by LC capping through the transformation of fractions from mobile and less stable forms to more stable forms. Furthermore, LC capping led to an increase in the Eh value, which promoted the oxidation of soluble Fe (Ⅱ) and soluble Mn. The significantly positive correlation and synchronized variations observed between SRP, soluble As, soluble W, and soluble Fe (II) indicated that the effects of LC on Fe redox played a crucial role in immobilizing sediment internal P, As and W. However, the oxidation of Mn, promoted by LC, played a more significant role in immobilizing sediment internal As than P and W. These effects resulted in LC capping achieving the highest reduction of SRP, soluble As and soluble W flux at 145.22, 22.19, and 0.58 µg m-2d-1. It is of note that LC capping did not lead to an elevated release hazard of Co, Ni, Cu, and Pb, barring Cd. Besides, LC capping did not modify the entire microbial communities in the sediment, but altered the proportional representation of specific microorganisms. Generally, LC has potential as a capping agent capable of simultaneously immobilizing sediment internal P, As and W.


Assuntos
Arsênio , Lantânio , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Tungstênio , Fósforo , Sedimentos Geológicos , Lagos
4.
Environ Pollut ; 343: 123161, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38104760

RESUMO

In this study, ceria nanoparticle (CNP) was used as a capping agent to investigate the efficiency and mechanism of simultaneously controlling the release of sediment internal Arsenic (As) and tungsten (W). The results of incubation experiment demonstrated that CNP capping reduced soluble As and W by 81.80% and 97.97% in overlying water, respectively; soluble As and W by 65.64% and 60.13% in pore water, respectively; and labile As and W in sediment by 45.20% and 53.20%, respectively. The main mechanism of CNP controlling sediment internal As and W was through adsorption via ligand exchange and inner-sphere complexation, as determined through adsorption experiments, XPS and FIRT spectra analysis. Besides, CNP also acted as an oxidant, facilitating the oxidation of AsⅢ to AsV and thereby enhancing the adsorption of soluble As. Additionally, sediment As and W fractions experiments demonstrated that the immobilization of As and W with CNP treatment via transforming mobile to stable fractions was another mechanism inhibiting sediment As and W release. The obtained significant positive correlation between soluble As/W and Fe/Mn, labile As/W and Fe/Mn indicated that iron (Fe) and manganese (Mn) oxidation, influenced by CNP, serve as additional mechanisms. Moreover, Fe redox plays a crucial role in controlling internal As and W, while Mn redox plays a more significant role in controlling As compared to W. Meanwhile, CNP capping effectively prevented the release of As and W by reducing the activity of microorganisms that degrade Fe-bound As and W and reduced the release risk of V, Cr, Co, Ni, and Zn from sediments. Overall, this study proved that CNP was a suitable capping agent for simultaneously controlling the release of As and W from sediment.


Assuntos
Arsênio , Metais Pesados , Poluentes Químicos da Água , Arsênio/análise , Tungstênio , Sedimentos Geológicos , Metais Pesados/análise , Manganês/análise , Água , Poluentes Químicos da Água/análise , Fósforo
5.
Chemosphere ; 341: 140085, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690549

RESUMO

BACKGROUND: Few studies have investigated the associations between heavy metals and anxiety. The purpose of this study was to examine the associations between single and combined exposure to heavy metals and anxiety. METHODS: This study employed data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2012. Anxiety was assessed by patients self-reporting the number of anxious days per month. First, we evaluated the associations between 10 heavy metals single exposure and anxiety by multivariable logistic regression. We then selected 5 heavy metals (cadmium, antimony, cobalt, tungsten, and uranium) for further analysis by elastic net regression. Subsequently, principal component analysis (PCA), weighted quantile regression (WQS), and Bayesian kernel machine regression (BKMR) were utilized to evaluate the associations between 5 heavy metals co-exposure and anxiety. RESULTS: This study included 4512 participants, among whom 1206 participants were in an anxiety state. Urinary cadmium and antimony were separately related to an increased risk of anxiety (p for trend <0.01 and < 0.01, respectively). In PCA analysis, PC1 was associated with an increased risk of anxiety (p for trend <0.001). In WQS analysis, the positive WQS index was substantially linked with the risk of anxiety (OR (95%CI): 1.23 (1.04,1.39)). In BKMR analysis, the overall effects of co-exposure to heavy metals were positively connected with anxiety. CONCLUSION: Our study identified a positive correlation between individual exposure to cadmium and antimony and the risk of anxiety. Additionally, the co-exposure to cadmium, antimony, cobalt, tungsten, and uranium was associated with an increased risk of anxiety.


Assuntos
Antimônio , Urânio , Humanos , Adulto , Inquéritos Nutricionais , Cádmio , Tungstênio , Teorema de Bayes , Ansiedade/epidemiologia , Cobalto
6.
Environ Sci Pollut Res Int ; 30(40): 92937-92949, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37498425

RESUMO

Metals exposure has gained increasing attention in the hypertension prevention. However, previous studies have focused on the impacts of single or separated metals on hypertension, and the critical metals contributing to the prevalence of hypertension are still under discussion. We collected data from 5092 participants across three consecutive National Health and Nutrition Examination Survey (NHANES) circles (2011-2016). Weighted logistic regression, weighted quantile sum (WQS) regression, quantile-based g-computation (QGC), and Bayesian kernel machine regression (BKMR) analyses were conducted to evaluate the combined and individual effects of 15 urinary metals, as well as to identify the critical metals on the development of hypertension. In our study, the weighted prevalence of hypertension was 37.9%, and the average age was 47.42 years. Manganese, uranium and tin were found as the independent risk factors for hypertension, while barium, lead, and thallium were found to have protective effects against hypertension. Lead, barium, tungsten, uranium, and tin were determined as critical elements for the prediction of hypertension. No significant interaction relationship was detected between multiple metals. There might be potential positive combined effects of urinary metal mixture on hypertension. Tungsten, uranium, and tin were positively associated with hypertension while lead and barium were negatively associated with hypertension. The underlying mechanisms of urinary metal exposure on the risk of hypertension deserve further investigations.


Assuntos
Hipertensão , Urânio , Humanos , Pessoa de Meia-Idade , Inquéritos Nutricionais , Exposição Ambiental/análise , Bário , Tungstênio , Teorema de Bayes , Estanho , Modelos Estatísticos , Hipertensão/induzido quimicamente , Hipertensão/epidemiologia
7.
Environ Res ; 231(Pt 1): 116060, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37149024

RESUMO

In this study, CaO2 was used as a capping material to control the release of Phosphate (P) and tungsten (W) from the sediment due to its oxygen-releasing and oxidative properties. The results revealed significant decreases in SRP and soluble W concentrations after the addition of CaO2. The mechanisms of P and W adsorption by CaO2 were mainly chemisorption and ligand exchange mechanisms. In addition, the results showed significant increases in HCl-P and amorphous and poorly crystalline(oxyhydr)oxides bound W after the addition of CaO2. The highest reduction rates of sediment SRP and soluble W release were 37 and 43%, respectively. Furthermore, CaO2 can promote the redox of iron (Fe) and manganese (Mn). On the other hand, a significant positive correlation was observed between SRP/soluble W and soluble Fe (II) and between SRP/soluble W and soluble Mn, indicating that the effects of CaO2 on Fe and Mn redox play a crucial role in controlling P and W releases from sediments. However, the redox of Fe plays a key role in controlling sediment P and W release. Therefore, CaO2 addition can simultaneously inhibit sediment internal P and W release.


Assuntos
Fósforo , Poluentes Químicos da Água , Tungstênio , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Manganês
8.
J Food Sci ; 88(4): 1506-1522, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36798025

RESUMO

Different wavelength emitting infrared (IR) lamps (transparent quartz tungsten (TQT), ruby-coated quartz tungsten (RCQT), and ceramic) were used for dry peeling and evaluating the spectral characteristics of emitted radiations. The maximum temperatures for ceramic, RCQT, and TQT were 560, 662, and 861°C, respectively. The peak wavelength determined by Wien's law was between 3.37 and 21.47 µm. Comparatively, longer wavelength was emitted by ceramic lamp. The spectral emissive power determined by Stefan Boltzmann's law was 1.14-37.49 kW m-2 using the IR emitters at different power levels. The radiant efficiency was higher for the ceramic lamp. The peak wavelength and emissive power had a major influence on the peeling performance and quality during IR peeling. The optimized parameters for IR dry peeling of shallots are 60 mm distance between lamp and product, 59.74% IR power level, 15 min of heating time using the ceramic (peak wavelength 8.16 µm) lamp. Practical Application: Infrared dry peeling of shallots is a sustainable alternative to traditional peeling methods that leaves adverse environmental footprints. Spectral characteristics of the infrared lamp can be used to determine the suitable emitter for the dry-peeling operation. It is necessary to check the wavelength emitted by the source for designing the IR system based on the food product and application. This study will be helpful in food processing industries to use an effective infrared lamp that can efficiently peel the agricultural product and sustainably maintain quality.


Assuntos
Cebolinha Branca , Cebolas , Quartzo , Tungstênio , Raios Infravermelhos
9.
Health Phys ; 124(5): 431-437, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661893

RESUMO

ABSTRACT: Appendix D of Title 40 Part 61 of the US Code of Federal Regulations (CFR) provides a procedure that US Department of Energy (US DOE) facility owners and operators can use to estimate radionuclide emissions to the atmosphere for dose calculations instead of measuring emissions for minor sources under the 40 CFR Part 61, Subpart H, National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities, regulation. The procedure assumes that any radioactive material heated above 100 °C is completely vaporized and emitted to the atmosphere. In 1991, the US DOE Oak Ridge Reservation (ORR) requested approval to use different release fractions (RFs) for uranium because of its high melting and boiling points. In response to the request, the US Environmental Protection Agency (US EPA) Region IV approved the use of modified RFs for elemental uranium provided no reaction had taken place to alter its chemical form. In 2015, the ORR requested approval to use different RFs for tungsten, again because of its high melting and boiling points. EPA Region IV approved the use of modified RFs for heated radioactive tungsten metal. In accordance with the two precedents set for heating uranium and radioactive tungsten metals, in 2016, the ORR requested approval to use modified RFs in a similar fashion for other radioactive solid metals and compounds with melting and boiling points above 500 °C that might be heated above 100 °C in future research projects and experiments. EPA Region IV again granted approval to use modified RFs for the list of compounds. This note discusses the proposed modified RFs and their development.


Assuntos
Poluentes Radioativos do Ar , Radônio , Urânio , Tungstênio , Radioisótopos/análise , Poluentes Radioativos do Ar/análise
10.
Molecules ; 27(22)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36431926

RESUMO

As typical transition metal dichalcogenides (TMDC), tungsten selenide (WSe2) nanosheets (nano-WSe2) are widely used in various fields due to their layered structures and highly tunable electronic and magnetic properties, which results in the unwanted release of tungsten (W) and selenium (Se) into the environment. However, the environmental effects of nano-WSe2 in plants are still unclear. Herein, we evaluated the impacts and fate of nano-WSe2 and micro-WSe2 in rice plants (Oryza sativa L.). It was found that both nano-WSe2 and micro-WSe2 did not affect the germination of rice seeds up to 5000 mg/L but nano-WSe2 affected the growth of rice seedlings with shortened root lengths. The uptake and transportation of WSe2 was found to be size-dependent. Moreover, W in WSe2 was oxidized to tungstate while Se was transformed to selenocysteine, selenomethionine, SeIV and SeVI in the roots of rice when exposed to nano-WSe2, suggesting the transformation of nano-WSe2 in rice plants. The exposure to nano-WSe2 brought lipid peroxidative damage to rice seedlings. However, Se in nano-WSe2 did not contribute to the synthesis of glutathione peroxidase (GSH-Px) since the latter did not change when exposed to nano-WSe2. This is the first report on the impacts and fate of nano-WSe2 in rice plants, which has raised environmental safety concerns about the wide application of TMDCs, such as WSe2 nanosheets.


Assuntos
Oryza , Selênio , Tungstênio , Plântula , Selênio/farmacologia , Raízes de Plantas
11.
ACS Appl Mater Interfaces ; 14(45): 50557-50568, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36322879

RESUMO

Single ionizing radiation at a tolerable dose is ineffectual in eliminating malignancies but readily generates harmful effects on surrounding normal tissues. Herein, we intelligently fabricated novel wolfram-doped polypyrrole (WPPy) through a simple oxidative polymerization method with WCl6 as an oxidizing catalyst, which possessed good biocompatibility, high photothermal conversion, and intensive radiosensitivity capacities to concurrently serve as a photothermal reagent and a radiosensitizer for hyperthermia-synergized radiotherapy (RT) against a malignant tumor. In comparison with traditional polypyrrole without noble metal doping, the innovative introduction of WCl6 not only successfully launched the polymerization of a pyrrole monomer but also endowed WPPy with additional radiosensitization. More importantly, after further decoration with an active targeted component (SP94 polypeptide), the obtained WPPy@SP94 significantly increased tumor internalization and accumulation in vitro and in vivo and induced obvious DNA damage as well as robust ROS generation under X-ray irradiation, which meanwhile synergized with strong photonic hyperthermia to effectively inhibit tumor growth by single drug injection. Moreover, such biocompatible WPPy@SP94 showed negligible adverse effects on normal cells and tissues. WPPy@SP94 developed in this study not only expands the category of polypyrrole chemical syntheses but also sheds light on WPPy@SP94-based radiosensitizers for cancer RT.


Assuntos
Hipertermia Induzida , Neoplasias , Radiossensibilizantes , Humanos , Polímeros , Pirróis , Tungstênio , Neoplasias/radioterapia , Radiossensibilizantes/farmacologia , Hipertermia , Linhagem Celular Tumoral
12.
Environ Res ; 215(Pt 3): 114435, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36174761

RESUMO

BACKGROUND: It is well-documented that heavy metals are associated with cardiovascular disease (CVD). However, there is few studies exploring effect of metal mixture on CVD. Therefore, the primary objective of present study was to investigate the joint effect of heavy metals on CVD and to identify the most influential metals in the mixture. METHODS: Original data for study subjects were obtained from the National Health and Nutrition Examination Survey. In this study, adults with complete data on 12 kinds of urinary metals (antimony, arsenic, barium, cadmium, cobalt, cesium, molybdenum, mercury, lead, thallium, tungsten, and uranium), cardiovascular disease, and core covariates were enrolled. We applied five different statistical strategies to examine the CVD risk with metal exposure, including multivariate logistic regression, adaptive elastic net combined with Environmental Risk Score, Quantile g-computation, Weighted Quantile Sum regression, and Bayesian kernel machine regression. RESULTS: Higher levels of cadmium, tungsten, cobalt, and antimony were significantly associated with Increased risk of CVD when covariates were adjusted for multivariate logistic regression. The results from multi-pollutant strategies all indicated that metal mixture was positively associated with the risk of CVD. Based on the results of multiple statistical strategies, it was determined that cadmium, tungsten, cobalt, and antimony exhibited the strongest positive correlations, whereas barium, lead, molybdenum, and thallium were most associated with negative correlations. CONCLUSION: Overall, our study demonstrates that exposure to heavy metal mixture is linked to a higher risk of CVD. Meanwhile, this association may be driven primarily by cadmium, tungsten, cobalt, and antimony. Further prospective studies are warranted to validate or refute our primary findings as well as to identify other important heavy metals linked with CVD.


Assuntos
Arsênio , Doenças Cardiovasculares , Poluentes Ambientais , Mercúrio , Urânio , Adulto , Antimônio/toxicidade , Bário , Teorema de Bayes , Cádmio , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Césio , Cobalto , Exposição Ambiental/análise , Poluentes Ambientais/toxicidade , Humanos , Modelos Estatísticos , Molibdênio , Inquéritos Nutricionais , Tálio , Tungstênio
13.
J Biotechnol ; 356: 60-64, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35878811

RESUMO

The effect of tungsten and selenium on cell growth and production of metabolites such as acetic acid and ethanol when fermenting syngas using "Clostridium autoethanogenum" was investigated to improve the process efficiency. General concentrations of selenium and tungsten in the medium are 0.01 µM during acetogenic syngas fermentation. We conducted culture experiments at concentrations of 0, 0.001, 0.01 and 0.1 µM for each heavy metal. The effect of selenium on cell growth and total metabolite production was greater than that of tungsten as the effect of selenium on formate dehydrogenase, an important enzyme of the Wood-Ljungdahl pathway, is greater than that of tungsten. Although an increase in tungsten had a marginal effect on total metabolite production, the ethanol/acetic acid production ratio increased significantly due to a decrease in acetic acid and an increase in ethanol production. Thus, tungsten plays a key role in activating aldehyde:ferredoxin oxidoreductase, a key enzyme in the reduction of acetate to ethanol. A specific ethanol productivity of 0.462 g ethanol/g DCW∙d was obtained in a culture using 0.01 µM selenium and 0.1 µM tungsten, which was 2.18 times higher than when using 0.01 µM of both selenium and tungsten.


Assuntos
Selênio , Tungstênio , Ácido Acético/metabolismo , Clostridium/metabolismo , Etanol/metabolismo , Fermentação , Selênio/metabolismo , Tungstênio/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-35886481

RESUMO

As a toxic element, tungsten (W) in elevated concentrations, originating from human activities or geological sources, poses a severe threat to the environment. However, there has been a lack of robust remediation techniques focusing on aqueous tungsten contamination with varying initial concentrations, because only recently have the toxicity and the environmental threat of tungsten been fully realized. In this study, the removal of tungsten from an aqueous solution by hydrocalumite was investigated for the first time. Systematic removal experiments were carried out at designated contact time, temperature, and initial tungsten concentration. The results showed that hydrocalumite is capable of effectively removing tungsten under various conditions, especially at high initial tungsten concentrations, with the maximum uptake capacity being up to 1120.5 mg (tungsten)/g (hydrocalumite). The mechanisms of tungsten removal were studied based on the measured chemical compositions of the solution samples and their PHREEQC simulations as well as the solid sample characterization by XRD, SEM-EDX, and XPS. At low initial tungsten concentrations (below 1 mmol/L), anion exchange between the tungsten in solution and the Cl in the hydrocalumite interlayers played a critical role in tungsten removal. At high initial tungsten concentrations (higher than 5 mmol/L), the removal of W from the solution was solely caused by the precipitation of scheelite (CaWO4), facilitated by the substantial release of Ca2+ from hydrocalumite dissolution. At moderate tungsten concentrations (1-5 mmol/L), however, both mechanisms were responsible for the uptake of tungsten, with scheelite precipitation being more important. Hydrocalumite is promising for wide use in the treatment of high-tungsten natural waters or wastewaters.


Assuntos
Tungstênio , Purificação da Água , Óxido de Alumínio , Cloreto de Cálcio , Humanos , Solubilidade , Água , Purificação da Água/métodos
15.
J Inorg Biochem ; 234: 111904, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35779405

RESUMO

Some N2-fixing bacteria store Mo to maintain the formation of the vital FeMo-cofactor dependent nitrogenase under Mo depleting conditions. The Mo storage protein (MoSto), developed for this purpose, has the unique capability to compactly deposit molybdate as polyoxometalate (POM) clusters in a (αß)3 hexameric cage; the same occurs with the physicochemically related tungstate. To explore the structural diversity of W-based POM clusters, MoSto loaded under different conditions with tungstate and two site-specifically modified MoSto variants were structurally characterized by X-ray crystallography or single-particle cryo-EM. The MoSto cage contains five major locations for POM clusters occupied among others by heptanuclear, Keggin ion and even Dawson-like species also found in bulk solvent under defined conditions. We found both lacunary derivatives of these archetypical POM clusters with missing WOx units at positions exposed to bulk solvent and expanded derivatives with additional WOx units next to protecting polypeptide segments or other POM clusters. The cryo-EM map, unexpectedly, reveals a POM cluster in the cage center anchored to the wall by a WOx linker. Interestingly, distinct POM cluster structures can originate from identical, highly occupied core fragments of three to seven WOx units that partly correspond to those found in MoSto loaded with molybdate. These core fragments are firmly bound to the complementary protein template in contrast to the more variable, less occupied residual parts of the visible POM clusters. Due to their higher stability, W-based POM clusters are, on average, larger and more diverse than their Mo-based counterparts.


Assuntos
Molibdênio , Tungstênio , Ânions , Molibdênio/química , Oxigênio , Polieletrólitos , Solventes , Tungstênio/química
16.
Environ Sci Pollut Res Int ; 29(48): 73480-73491, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35624372

RESUMO

Metals, arsenic, and polycyclic aromatic hydrocarbons (PAHs) have all been linked to respiratory diseases. Chronic bronchitis, which is a form of chronic obstructive pulmonary disease (COPD), is a major public health concern and source of morbidity and mortality in the US. The purpose of this study was to analyze the correlation of 14 urinary metals (antimony, barium, cadmium, cesium, cobalt, lead, manganese, mercury, molybdenum, strontium, thallium, tin, tungsten, uranium), seven species of arsenic, and seven forms of polycyclic aromatic hydrocarbon (PAH) concentrations and chronic bronchitis in the US population. A cross-sectional analysis using three datasets from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2016 in adults, aged 20 years and older. Chronic bronchitis was determined using a self-questionnaire from the NHANES dataset. A specialized weighted complex survey design analysis package was used to analyze NHANES data. Multivariate logistic regression models were used to determine the correlation between urinary metals, arsenic, PAHs, and chronic bronchitis. Models were adjusted for lifestyle and demographic factors. A total of 4186 participants were analyzed; 49.8% were female and 40.5% were non-Hispanic White. All seven types of PAHs showed a positive association with chronic bronchitis (1-hydroxynaphthalene odds ratio (OR): 1.559, 95% confidence interval (CI): 1.271-1.912; 2-hydroxynaphthalene OR: 2.498, 95% CI: 1.524-4.095; 3-hydroxyfluorene OR: 2.752, 95% CI: 2.100-3.608; 2-hydroxyfluorene OR: 3.461, 95% CI: 2.438-4.914; 1-hydroxyphenanthrene OR: 2.442, 95% CI: 1.515-3.937; 1-hydroxypyrene OR: 2.828, 95% CI: 1.728-4.629; 2 & 3-hydroxyphenanthrene OR: 3.690, 95% CI: 2.309-5.896). Of the metals, only urinary cadmium showed a statistically significant positive association (OR: 2.435, 95% CI: 1.401-4.235) with chronic bronchitis. No other metals or arsenic were correlated with chronic bronchitis. Seven forms of urinary PAHs, cadmium, and several demographic factors were associated with chronic bronchitis.


Assuntos
Arsênio , Bronquite Crônica , Mercúrio , Hidrocarbonetos Policíclicos Aromáticos , Urânio , Adulto , Antimônio , Bário , Biomarcadores , Bronquite Crônica/induzido quimicamente , Bronquite Crônica/epidemiologia , Cádmio , Césio , Cobalto , Estudos Transversais , Feminino , Humanos , Masculino , Manganês , Molibdênio , Inquéritos Nutricionais , Hidrocarbonetos Policíclicos Aromáticos/análise , Estrôncio , Tálio , Estanho , Tungstênio , Urânio/análise
17.
Folia Microbiol (Praha) ; 67(5): 707-719, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35415828

RESUMO

Persistent use of pesticides and animal manure in agricultural soils inadvertently introduced heavy metals and antibiotic/antibiotic resistance genes (ARGs) into the soil with deleterious consequences. The microbiome and heavy metal and antibiotic resistome of a pesticide and animal manure inundated agricultural soil (SL6) obtained from a vegetable farm at Otte, Eiyenkorin, Kwara State, Nigeria, was deciphered via shotgun metagenomics and functional annotation of putative ORFs (open reading frames). Structural metagenomics of SL6 microbiome revealed 29 phyla, 49 classes, 94 orders, 183 families, 366 genera, 424 species, and 260 strains with the preponderance of the phyla Proteobacteria (40%) and Actinobacteria (36%), classes Actinobacteria (36%), Alphaproteobacteria (18%), and Gammaproteobacteria (17%), and genera Kocuria (16%), Sphingobacterium (11%), and Brevundimonas (10%), respectively. Heavy metal resistance genes annotation conducted using Biocide and Metal Resistance Gene Database (BacMet) revealed the detection of genes responsible for the uptake, transport, detoxification, efflux, and regulation of copper, cadmium, zinc, nickel, chromium, cobalt, selenium, tungsten, mercury, and several others. ARG annotation using the Antibiotic Resistance Gene-annotation (ARG-ANNOT) revealed ARGs for 11 antibiotic classes with the preponderance of ß-lactamases, mobilized colistin resistance determinant (mcr-1), macrolide-lincosamide-streptogramin (MLS), glycopeptide, and aminoglycoside resistance genes, among others. The persistent use of pesticide and animal manure is strongly believed to play a major role in the proliferation of heavy metal and antibiotic resistance genes in the soil. This study revealed that agricultural soils inundated with pesticide and animal manure use are potential hotspots for ARG spread and may accentuate the spread of multidrug resistant clinical pathogens.


Assuntos
Desinfetantes , Mercúrio , Microbiota , Praguicidas , Selênio , Aminoglicosídeos , Animais , Antibacterianos/farmacologia , Cádmio , Cromo , Cobalto , Colistina , Cobre , Genes Bacterianos , Glicopeptídeos , Lincosamidas , Macrolídeos , Esterco/microbiologia , Metagenômica , Microbiota/genética , Níquel , Praguicidas/farmacologia , Solo/química , Microbiologia do Solo , Estreptograminas , Tungstênio , Zinco , beta-Lactamases/genética
18.
J Appl Genet ; 62(1): 85-92, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33409932

RESUMO

Tungsten oxide nanoparticles or nanopowder (WO3NPs) is commonly used in various industries and also in biomedical applications such as additives, pigments, and biomedical sensors. Non-judicious excessive use of these nanoparticles (NPs) could be a serious human health concern. Therefore, the current study aimed to explore the cytotoxic and genotoxic assessment of WO3NPs through Allium cepa anaphase-telophase and comet assays. Nanoparticles were characterized through the scanning and transmission electron microscopy (TEM), zetasizer, and energy-dispersive X-ray spectroscopy. The mean size and the average diameter of WO3NPs were determined as 21.57 ± 2.48 nm and 349.42 ± 80.65 nm using TEM and a Zetasizer measurement system, respectively. Five concentrations (12.5 mg/L, 25 mg/L, 50 mg/L, 75 mg/L, and 100 mg/L) of WO3NPs were employed on the Allium cepa (A. cepa) roots for 4 h. Significant (p ≤ 0.05) decrease in mitotic index (MI) was shown by WO3NPs at all concentrations. The increase of chromosomal aberrations (CAs) was also observed in a concentration-dependent manner due to the WO3NPs exposure. There was a significant increase (p ≤ 0.05) in DNA damage at all concentrations of WO3NPs on the A. cepa cells. It was concluded that WO3NPs had cytotoxic and genotoxic effects on A. cepa meristematic cells. Moreover, further cytogenetic effects of WO3NPs should be investigated at the molecular level to assess its safety margin.


Assuntos
Nanopartículas , Cebolas/genética , Óxidos/toxicidade , Tungstênio/toxicidade , Aberrações Cromossômicas , Ensaio Cometa , Dano ao DNA , Nanopartículas/toxicidade , Cebolas/efeitos dos fármacos , Raízes de Plantas , Telófase
19.
Molecules ; 27(1)2021 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-35011360

RESUMO

Anticancer treatment is largely affected by the hypoxic tumor microenvironment (TME), which causes the resistance of the tumor to radiotherapy. Combining radiosensitizer compounds and O2 self-enriched moieties is an emerging strategy in hypoxic-tumor treatments. Herein, we engineered GdW10@PDA-CAT (K3Na4H2GdW10O36·2H2O, GdW10, polydopamine, PDA, catalase, CAT) composites as a radiosensitizer for the TME-manipulated enhancement of radiotherapy. In the composites, Gd (Z = 64) and W (Z = 74), as the high Z elements, make X-ray gather in tumor cells, thereby enhancing DNA damage induced by radiation. CAT can convert H2O2 to O2 and H2O to enhance the X-ray effect under hypoxic TME. CAT and PDA modification enhances the biocompatibility of the composites. Our results showed that GdW10@PDA-CAT composites increased the efficiency of radiotherapy in HT29 cells in culture. This polyoxometalates and O2 self-supplement composites provide a promising radiosensitizer for the radiotherapy field.


Assuntos
Gadolínio/química , Nanocompostos/química , Radiossensibilizantes/química , Hipóxia Tumoral/efeitos da radiação , Tungstênio/química , Ânions/química , Materiais Biocompatíveis/química , Catalase/metabolismo , Linhagem Celular Tumoral , Células HT29 , Humanos , Peróxido de Hidrogênio/metabolismo , Indóis/química , Oxigênio/metabolismo , Polieletrólitos/química , Polímeros/química , Radiossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral
20.
Environ Technol ; 42(26): 4104-4114, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32194007

RESUMO

In this study, a highly efficient and stable phosphorus-doped Tungsten trioxide (P-WO3) photocatalyst was successfully synthesized using a combination of hydrothermal and post-calcination method. The microstructures, morphologies and optical properties of the obtained WO3 and P-WO3 samples were characterized. The results showed that P was uniformly doped into the WO3 lattice in a pentavalent-oxidation state (P5+). The charge carrier traps were also formed, which could accept the photoelectrons. Furthermore, the band gap energy was reduced from 2.4 to 2.33 ev. The photocatalytic performance of the obtained P-WO3 samples with different P concentrations were then tested by photocatalytic degradation of methyl blue (MB). It was found that the 6%-P-WO3 sample exhibited the highest photocatalytic activity, with 96% of MB being able to be degraded within 120 min, which was more than four times higher than that of the pure WO3. The practicality of the prepared P-WO3 was also evaluated using samples from two domestic wastewater treatment plants. The P-WO3 had a high photodegradation performance in treating low concentration of organic matters from real wastewater. The photocatalysis of P-WO3 could be mainly initiated by the production of hydroxyl radical (·OH) and photogenerated hole (h+).


Assuntos
Nanoestruturas , Fósforo , Catálise , Óxidos , Tungstênio
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