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1.
J Hazard Mater ; 416: 125885, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492823

RESUMO

Iron-based materials have been widely used for treating uranium-containing wastewater. However, the iron-uranium solids originating by treating radioactive water through pollutant transfer methods has become a new uncontrolled source of persistent radioactive pollution. The safe disposal of such hazardous waste is not yet well-resolved. The electrochemical mineralization method was developed to rapidly purify uranium-containing wastewater through lattice doping in magnetite and recover uranium without generating any pollutants. An unexpected isolation of U3O8 from uranium-doped magnetite was discovered through in-situ XRD with a temperature variation from 300 °C to 700 °C. Through HRTEM and DFT calculation, it was confirmed that the destruction of the inverse spinel crystal structure during the gradual transformation of magnetite into γ-Fe2O3 and α-Fe2O3 promoted the migration, aggregation, and isolation of uranium atoms. Uniquely generated U3O8 and Fe2O3 were easily separated and over 80% uranium and 99.5% iron could be recovered. These results demonstrate a new strategy for uranium utilization and the environmentally friendly treatment of uranium-containing wastewater.


Assuntos
Urânio , Poluentes Radioativos da Água , Ferro , Estresse Oxidativo , Águas Residuárias , Poluentes Radioativos da Água/análise
2.
Molecules ; 26(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500637

RESUMO

The most common cause of iron deficiency is an improperly balanced diet, in which the body's need for iron cannot be met by absorption of this element from food. Targeted iron supplementation and food fortification may be the main treatments for iron deficiency in the population. However, many iron-rich supplements and foods have low bioavailability of this element. In our study, we used yeast enriched with iron ions to produce flatbread. The yeast cells accumulated iron ions from the medium supplemented with Fe(NO3)3·9H2O, additionally one of the cultures was treated with pulsed electric field in order to increase the accumulation. The potential bioavailability of iron from flatbread containing 385.8 ± 4.12 mg of iron in 100 g dry mass was 10.83 ± 0.94%. All the flatbreads had a moderate glycemic index. There were no significant differences in antioxidant activity against DPPH• between flatbread with iron-enriched and non-iron-enriched yeast. Sensory evaluation showed that this product is acceptable to consumers since no metallic aftertaste was detected. Iron enriched flatbread can potentially be an alternative to dietary supplements in iron deficiency states.


Assuntos
Pão/microbiologia , Suplementos Nutricionais/microbiologia , Alimentos Fortificados/microbiologia , Ferro/metabolismo , Saccharomyces cerevisiae/metabolismo , Anemia Ferropriva/metabolismo , Anemia Ferropriva/prevenção & controle , Antioxidantes/metabolismo , Disponibilidade Biológica , Índice Glicêmico/fisiologia , Humanos
3.
Chemosphere ; 283: 131170, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34467949

RESUMO

The Fenton process activated by Zero Valent Iron (ZVI-Fenton) is shown here to effectively remove antibiotics reserved for hospital settings (specifically used to treat antibiotic-resistant infections) from wastewater, thereby helping in the fight against bacterial resistance. Effective degradation of cefazolin, imipenem and vancomycin in real urban wastewater was achieved at pH 5, which is quite near neutrality when compared with classic Fenton that works effectively at pH 3-4. The possibility to operate successfully at pH 5 has several advantages compared to operation at lower pH values: (i) lower reagent costs for pH adjustment; (ii) insignificant impact on wastewater conductivity, because lesser acid is required to acidify and lesser or no base for neutralization; (iii) undetectable release of dissolved Fe, which could otherwise be an issue for wastewater quality. The cost of reagents for the treatment ranges between 0.04 and 0.07 $ m-3, which looks very suitable for practical applications. The structures of the degradation intermediates of the studied antibiotics and their likely abundance suggest that, once the primary compound is eliminated, most of the potential to trigger antibiotic action has been removed. Application of the ZVI-Fenton technique to wastewater treatment could considerably lower the possibility for antibiotics to trigger the development of resistance in bacteria.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Antibacterianos , Hospitais , Peróxido de Hidrogênio , Ferro , Oxirredução , Poluentes Químicos da Água/análise
4.
J Hazard Mater ; 416: 125916, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492849

RESUMO

Cadmium (Cd) pollution in paddy soil seriously endangers food safety production. To investigate the effects and microbiological mechanisms of calcium-magnesium-phosphate (CMP) fertilizer application on Cd reduction in rice, field experiments were conducted in Cd-contaminated paddy soil. Compared with conventional compound fertilizer, CMP fertilizer treatments inhibited Cd uptake through plant roots, significantly decreasing Cd content in rice grains from 0.340 to 0.062 mg/kg. Soil pH and total Ca, Mg and P contents increased after CMP fertilizer application, resulting in a further decrease in soil available Cd content from 0.246 to 0.181 mg/kg. Specific extraction analysis recorded a decrease in both available Fe content and the ratio of nitrate to ammonium nitrogen, indicating that the soil Fe-N cycle was affected by the addition of CMP fertilizer. This finding was also recorded using soil bacterial community sequencing, with CMP fertilizer promoting the progress of nitrate-dependent Fe-oxidation driven by Thiobacillus (1.60-2.83%) and subsequent dissimilatory nitrate reduction to ammonium (DNRA) driven by Ignavibacteriae (1.01-1.92%); Fe-reduction driven by Anaeromyxobacter (3.09-2.23%) was also inhibited. Our results indicate that CMP fertilizer application regulates the Fe-N coupling cycle driven by the soil microbial community to benefit remediation of Cd contaminated paddy soil.


Assuntos
Microbiota , Oryza , Poluentes do Solo , Cádmio/análise , Cádmio/toxicidade , Cálcio , Fertilizantes/análise , Ferro , Óxido de Magnésio , Nitrogênio , Fosfatos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
5.
J Hazard Mater ; 416: 125924, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492856

RESUMO

The chitosan-stabilized biochar supported S-nZVI (CS@BC/S-nZVI) composite with low aggregation and superior antioxidation were successfully synthesized by liquid-phase reduction method for the outstanding removal of Cr(VI) from wastewater and characterized by SEM, BET, FTIR, XRD, and XPS. The optimized synthesis parameters of CS@BC/S-nZVI were determined as a 0.14 molar ratio of S/Fe and a 0.25 mass ratio of BC/Fe. The CS@BC/S-nZVI possessed a specific surface area of 199.246 m2/g and an average pore size and pore volume of 1.186 nm and 0.272 cc/g. The CS@BC/S-nZVI could remain reductive activity after Cr(VI) removal and present a remarkable tolerance to the coexisting ions during Cr(VI) removal. The adsorption data were fitted well by the pseudo-second order model and the Langmuir model. The removal of Cr(VI) by CS@BC/S-nZVI was an exothermic process with prominent Cr(VI) removal capacities of 244.07 mg/g at 120 min and 221.84 mg/g at 15 min at 25 â„ƒ. Further mechanism analysis proved that the binding of Cr(VI) to CS@BC/S-nZVI was mainly a synergistic effect of reduction and electrostatic attraction. Overall, these findings shed new light on the research of a novel S-nZVI compound and revealed the potential practical application of CS@BC/S-nZVI in the future heavy metal removal from wastewater.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Cromo , Poluentes Químicos da Água/análise
6.
J Hazard Mater ; 416: 125961, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492875

RESUMO

This study investigated the removal of vanadium from mining waters at a closed mine site (Mustavaara, Finland) using granular ferric oxyhydroxide (CFH-12) on pilot scale. Two filter systems, pilot A and pilot B, were placed in different streams, where the influent in pilot A contained a higher and very variable vanadium concentration (6.46-99.1 mg/L), while the pilot B treated influent had lower vanadium concentrations (0.443-2.33 mg/L). The operation periods were 51 days for pilot A and 127 days for pilot B. Water quality analyses revealed that vanadium was efficiently captured in the filter system in both pilots. X-ray fluorescence analysis revealed that the filter beds were not fully saturated with vanadium. X-ray photoelectron spectroscopy confirmed that oxidised vanadium (5+) existed in the used CFH-12 and the carbon content in the used material had increased due to the adsorbed organic compounds. For comparison, lab-scale coagulation experiments were conducted using ferric sulphate for the influent of pilot A (the sampled batch contained 15.9 mg/L V). The optimum coagulant dosage was 350 mg/L (>93% vanadium removal) at the original pH (7.8-7.9) of the influent, whereas the required coagulant amount decreased when the influent pH was adjusted to 4.6-4.8.


Assuntos
Vanádio , Poluentes Químicos da Água , Ferro , Mineração , Compostos Orgânicos , Qualidade da Água
7.
J Hazard Mater ; 416: 125972, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492881

RESUMO

In hydrometallurgy industry, the accumulation of iron removal residues containing heavy metal elements and toxic elements poses great threats to ecological systems. We propose a novel method to prevent the production of hazardous iron removal residues: firstly, neutralization precipitation is used to purify iron ions in solution; after sedimentation of the obtained suspension, only dense underflow is subjected to hydrothermal reaction, in which ferric hydroxide transforms into hematite crystal. Results showed that ferric hydroxide precipitated into a thin sedimentation layer at temperature greater than 60 °C. For hydrothermal treatment of the sedimentation layer, a high hydrothermal reaction temperature was conducive to complete transformation of ferric hydroxide into hematite. The precipitated ferric hydroxide firstly changed from the crystallite of goethite or lepidocrocite to amorphous particles, and then gradually formed spherical α-Fe2O3 monocrystalline with diameter of around 50 nm, as indicated by TEM and XRD results. At 200 °C, hematite precipitates with iron content of about 65% can be obtained. For iron-containing zinc/nickel/cobalt sulfate solution, controlling hydrothermal reaction temperature and acidity of the underflow solution can effectively avoid the generation of zinc/nickel/cobalt hydroxides or subsulfates in the hematite precipitates, thereby significantly reducing the loss of those valuable metals.


Assuntos
Ferro , Metais Pesados , Compostos Férricos , Reciclagem , Zinco
8.
J Hazard Mater ; 416: 126089, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492902

RESUMO

Acid mine drainage (AMD) formation is mainly caused by the oxidation of pyrite. Carrier-microencapsulation (CME) using metal-catecholate complexes has been proposed to passivate sulfide minerals by forming surface-protective coatings on their surfaces. Among the various metal-catecholate complexes, Ti-catecholate formed stable coatings having superior acid-resistance, but a thick enough passivating film required considerable time (ca. 14 days) to grow. Meanwhile, Fe-catecholates can form Fe-oxyhydroxide coatings within 2 days, however, they are less stable than Ti-based coating. To address these drawbacks of using a single metal-complex, this study investigated the concurrent use of Fe-catechol and Ti-catechol complexes for accelerating the formation of stable passivating coating on pyrite. Compared with a single metal-complex system, the coating formation was significantly accelerated in mixed system. Linear sweep voltammetry showed the simultaneous decomposition of [Fe(cat)]+ and [Ti(cat)3]2- as the main reason for improved coating formation. Electrochemical properties of coatings formed by single and mixed complex systems, confirmed by electrochemical impedance spectroscopy and cyclic voltammetry, indicated the coating formed in the mixed system had higher resistance and more electrochemically inert than the other cases. The simultaneous use of Fe-catechol and Ti-catechol complexes enhanced pyrite passivation by accelerating metal-complex decomposition and forming more stable coating composed of Fe2TiO5.


Assuntos
Ferro , Titânio , Catecóis , Sulfetos
9.
J Hazard Mater ; 416: 126119, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492914

RESUMO

Sulfidized nanoscale zerovalent iron (SNZVI) with improved reactivity and selectivity has shown great potential for environmental remediation. However, it is unclear if SNZVI could be applied for the remediation of soil washing solution, and how a soil-washing surfactant affects the reactivity and selectivity of SNZVI. Here, we assess the impact of Triton X-100 (TX-100) on the reactivity and selectivity of a sulfidized commercial NZVI toward tetrabromobisphenol A (TBBPA). While sulfidation of NZVI improved its reactivity and electron efficiency toward TBBPA, TX-100 could further improve these promoting effects, which was 8-21 and 4-7 times higher than those without TX-100, respectively, depending on TX-100 concentration. Because TX-100 could induce the solubilization of TBBPA, sorb onto the SNZVI surface, and favor the subsequent sorption and degradation of TBBPA. SNZVI performance for successive treatments of TBBPA contaminated water was also greatly improved by TX-100. Moreover, washing the TBBPA-contaminated soil with TX-100 could efficiently extract the TBBPA, and almost all of the TBBPA in the soil washing solution could be efficiently degraded by SNZVI. These results suggest that TX-100 is a good additive to SNZVI for improving its performance, and SNZVI coupled with TX-100 can be a promising technology for the remediation of TBBPA-contaminated soil.


Assuntos
Água Subterrânea , Tricloroetileno , Poluentes Químicos da Água , Ferro , Octoxinol , Bifenil Polibromatos , Solo
10.
J Hazard Mater ; 416: 126128, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492922

RESUMO

This study demonstrated that As(III) was appreciably removed by ferrate in the presence of straw biochar. Removal efficiency of As in ferrate/biochar system was over 91%, increased by 34% compared with ferrate alone ([biochar]0 = 10 mg/L, [ferrate]0 = 6 mg/L, [As(III)]0 = 200 µg/L). In the reaction process, As(III) was oxidized to As(V) mainly by ferrate, while ferrate was reduced into ferric (hydr)oxides and coated on the biochar. Biochar was oxidized in the reaction and its surface area, pore volume and the amount of Lewis acid functional groups were substantially improved, which provided interaction sites for As adsorption. Analysis of hydrodynamic diameter and zeta potential revealed that biochar interacted with the ferrate resulted ferric oxides and enlarged the Fe-C-As particle/floc, which promoted their settlement and thus the liquid-solid separation of As. As(V) was adsorbed on the surface of biochar and ferric (hydr)oxides through hydrogen bond, electrostatic attraction and As-(OFe) bond. Ferrate/biochar was not only effective for As removal, but removed 73.31% of As, 50.38% of Cd, and 75.27% of Tl when these hazardous species synchronously existed in polluted water (initial content: As, 100 µg/L; Cd, 50 µg/L; Tl, 1 µg/L). The combination of ferrate with biochar has potential for the remediation of hazardous species polluted water.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Ferro , Poluentes Químicos da Água/análise
11.
J Hazard Mater ; 416: 126136, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492925

RESUMO

Zero valent iron (ZVI) coupled with bioreactors is arising as a promising technology for antibiotic resistance genes (ARGs) mitigation, whereas the succession and behaviors of microbes caused by ZVI in relieving ARGs propagation remain unclear. Herein, the effects of ZVI on microbial quorum sensing (QS), quorum quenching (QQ) system and community dynamics were examined in anaerobic bioreactor fed with oxytetracycline (tet), to illustrate the roles of evolutive microbial communication and community composition in ARGs attenuation. With the addition of 5 g/L ZVI, the total absolute abundance of tet ARGs was retarded by approximate 95% and 72% in sludge and effluent after 25 days operation. The abundance of mobile genetic elements and the heredity of antibiotic resistant bacteria revealed the declined horizontal and vertical transfer of ARGs, which directly led to the reduced ARGs propagation. Potential mechanisms are that the positive effects of ZVI on QQ activity via the functional bacteria enrichment inhibited QS system and thus ARGs transfer. Partial least--squares path modeling further demonstrated that ARGs abundance was strongly limited by the dynamics of bacterial composition and thereby less frequent microbial communication. These results provide new insights into the mechanisms of antibiotic resistome remission in anaerobic bioreactor modified by ZVI.


Assuntos
Antibacterianos , Percepção de Quorum , Anaerobiose , Antibacterianos/farmacologia , Reatores Biológicos , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Ferro , Percepção de Quorum/genética , Esgotos
12.
Mater Sci Eng C Mater Biol Appl ; 128: 112282, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474835

RESUMO

Imaging of immune cells has wide implications in understanding disease progression and staging. While optical imaging is limited in penetration depth due to light properties, magnetic resonance (MR) imaging provides a more powerful tool for the imaging of deep tissues where immune cells reside. Due to poor MR signal to noise ratio, tracking of such cells typically requires contrast agents. This report presents an in-depth physical characterization and application of archaeal magnetoferritin for MR imaging of macrophages - an important component of the innate immune system that is the first line of defense and first responder in acute inflammation. Magnetoferritin is synthesized by loading iron in apoferritin in anaerobic condition at 65 °C. The loading method results in one order of magnitude enhancement of r1 and r2 relaxivities compared to standard ferritin synthesized by aerobic loading of iron at room temperature. Detailed characterizations of the magnetoferritin revealed a crystalline core structure that is distinct from previously reported ones indicating magnetite form. The magnetite core is more stable in the presence of reducing agents and has higher peroxidase-like activities compared to the core in standard loading. Co-incubation of macrophage cells with magnetoferritin in-vitro shows significantly higher enhancement in T2-MRI contrast of the immune cells compared to standard ferritin.


Assuntos
Apoferritinas , Nanopartículas de Magnetita , Meios de Contraste , Ferro/metabolismo , Macrófagos/metabolismo , Imageamento por Ressonância Magnética , Óxidos
13.
Sci Total Environ ; 792: 148454, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34465049

RESUMO

Nano zero-valent iron particles (nZVI, 0.09 wt%), micro zero-valent iron particles (mZVI, 0.09 wt%), granular activated carbon (GAC, 3.03 wt%), GAC supported nZVI (nZVI/GAC, 3.12 wt%) and nZVI&GAC (nZVI 0.09 wt%, GAC 3.03 wt%) were evaluated for their effects on polychlorinated biphenyls (PCBs) anaerobic reductive dechlorination, detoxification, as well as microbial community structure in Taihu Lake (China) sediment microcosms. The results showed that all of these five materials could stimulate PCBs reductive dechlorination, especially for dioxin-like PCB congeners, and nZVI&GAC had the best removal effect on PCBs. The reduction of total PCBs increased from 13.5% to 33.2%. H2 generated by zero-valent iron corrosion was utilized by organohalide-respiring bacteria (OHRB) to enhance the dechlorination of PCBs predominantly via meta chlorine removal in the short term. The addition of ZVI had little impact on the total bacterial abundance and the microbial community structure. The adsorption of GAC and potential bioremediation properties of attached biofilm could promote the long-term removal of PCBs. GAC, nZVI/GAC, nZVI&GAC had different influences on the microbial structure. These findings provide insights into the biostimulation technique for in situ remediations of PCBs contaminated sediments.


Assuntos
Microbiota , Bifenilos Policlorados , Biodegradação Ambiental , Catálise , Cloro , Sedimentos Geológicos , Ferro , Lagos , Bifenilos Policlorados/análise
14.
Sci Total Environ ; 792: 148546, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34465057

RESUMO

During the latest several decades, the continuous development of the economy and industry has brought more and more serious organic pollutants to the natural environment, which have inevitably aroused severe menace to human health and the environmental system. The nano zero-valent iron (NZVI) particles and NZVI-based materials have widely applied to remove organic pollutants. This article reviews the key advancements of different methods for the synthesis of NZVI and NZVI-based materials. Different modification methods (e.g., doped NZVI, encapsulated NZVI and supported NZVI) are also introduced detailedly for overcoming the defects of NZVI such as aggregation and easy oxidation. The removal of different organic pollutants including dyes, halogenated organic compounds, nitro-organic compounds, phenolic compounds, pesticides, and antibiotics are summarized. The interaction mechanisms, including adsorption, reduction, and active oxidation of organic pollutants by NZVI/NZVI-based composites, are discussed. The dyes are mainly removed by destroying their chromogenic group according to the reduction or the Fenton-like reaction with NZVI. The removal of halogenated organic compounds (HOCs) is realized by the dehalogenation process, including reductive elimination, hydrogenolysis, and hydrogenation. As for the nitro-organic compounds, three different reduction pathways as nitro-reduction (into amino), cleavage at the carbon­nitrogen bond or denitration of the NO2 group may take effect. The phenolic compounds can be mineralized into inorganic molecules, including CO2 and H2O, by Fenton oxidation. This review might provide the basis for future studies on developing more effective NZVI-based materials for the treatment of wastewaters contaminated by organic pollutants.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Corantes , Humanos , Águas Residuárias , Poluentes Químicos da Água/análise
15.
J Environ Sci (China) ; 108: 70-83, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34465438

RESUMO

Iron and nitrate (NO3-) are dominant physiologically required nutrients for phytoplankton growth, and iron may also play a key role in the marine nitrogen cycle. In this study, we investigated the temporal and spatial distributions of dissolved iron (DFe) and Fe(II) in the surface waters of Jiaozhou Bay (JZB) from April 2 to July 26, 2017. High concentrations of DFe and Fe(II) predominantly occurred in nearshore and estuarine stations and concentrations were generally higher in April and May. The highest DFe concentration was observed along the coast of Hongdao (51.55 nmol/L) in May, while the lowest concentration was observed in the western coastal region (2.88 nmol/L) in April. The highest and lowest Fe(II) concentrations were observed in the Licun estuary (22.42 nmol/L) and outer bay (0.50 nmol/L) in May, respectively. We calculated the proportions of nitrate, nitrite, and ammonium in dissolved inorganic nitrogen (DIN) as well as the ratio of Fe(II) to DFe in all four months. The mean Fe(II)/DFe ratio was 0.48 in April, 0.43 in May, 0.69 in June, and 0.32 in July. The mean ratio of NO3- to DIN was 0.78 in April, 0.54 in May, 0.20 in June, and 0.62 in July. NO3-/DIN continuously decreased in the first three months, while Fe(II)/DFe remained high, which suggests that the reduction of iron and nitrate occurred simultaneously in the surface waters of JZB.


Assuntos
Ferro , Nitratos , Baías , Ferro/análise , Fitoplâncton , Água do Mar
16.
J Med Case Rep ; 15(1): 472, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34517883

RESUMO

BACKGROUND: Anemia is a serious global health problem that affects individuals of all ages but particularly women of reproductive age. Iron deficiency anemia is one of the most common causes of anemia seen in women, with menstruation being one of the leading causes. Excessive, prolonged, and irregular uterine bleeding, also known as menometrorrhagia, can lead to severe anemia. In this case report, we present a case of a premenopausal woman with menometrorrhagia leading to severe iron deficiency anemia with record low hemoglobin. CASE PRESENTATION: A 42-year-old Hispanic woman with no known past medical history presented with a chief complaint of increasing fatigue and dizziness for 2 weeks. Initial vitals revealed temperature of 36.1 °C, blood pressure 107/47 mmHg, heart rate 87 beats/minute, respiratory rate 17 breaths/minute, and oxygen saturation 100% on room air. She was fully alert and oriented without any neurological deficits. Physical examination was otherwise notable for findings typical of anemia, including: marked pallor with pale mucous membranes and conjunctiva, a systolic flow murmur, and koilonychia of her fingernails. Her initial laboratory results showed a critically low hemoglobin of 1.4 g/dL and severe iron deficiency. After further diagnostic workup, her profound anemia was likely attributed to a long history of menometrorrhagia, and her remarkably stable presentation was due to impressive, years-long compensation. Over the course of her hospital stay, she received blood transfusions and intravenous iron repletion. Her symptoms of fatigue and dizziness resolved by the end of her hospital course, and she returned to her baseline ambulatory and activity level upon discharge. CONCLUSIONS: Critically low hemoglobin levels are typically associated with significant symptoms, physical examination findings, and hemodynamic instability. To our knowledge, this is the lowest recorded hemoglobin in a hemodynamically stable patient not requiring cardiac or supplemental oxygen support.


Assuntos
Anemia Ferropriva , Anemia , Menorragia , Adulto , Anemia Ferropriva/complicações , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/tratamento farmacológico , Feminino , Hemoglobinas , Humanos , Ferro
17.
Sensors (Basel) ; 21(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34502671

RESUMO

In recent years, the general and scientific interest in nutrition, digestion, and what role they play in our body has increased, and there is still much work to be carried out in the field of developing sensors and techniques that are capable of identifying and quantifying the chemical species involved in these processes. Iron deficiency is the most common and widespread nutritional disorder that mainly affects the health of children and women. Iron from the diet may be available as heme or organic iron, or as non-heme or inorganic iron. The absorption of non-heme iron requires its solubilization and reduction in the ferric state to ferrous that begins in the gastric acid environment, because iron in the ferric state is very poorly absorbable. There are chemical species with reducing capacity (antioxidants) that also have the ability to reduce iron, such as ascorbic acid. This paper aims to develop a sensor for measuring the release of encapsulated active compounds, in different media, based on dielectric properties measurement in the radio frequency range. An impedance sensor able to measure the release of microencapsulated active compounds was developed. The sensor was tested with calcium alginate beads encapsulating iron ions and ascorbic acid as active compounds. The prediction and measurement potential of this sensor was improved by developing a thermodynamic model that allows obtaining kinetic parameters that will allow suitable encapsulation design for subsequent release.


Assuntos
Ácido Ascórbico , Ferro , Antioxidantes , Criança , Dieta , Feminino , Compostos Férricos , Compostos Ferrosos , Heme , Humanos
18.
Water Sci Technol ; 84(5): 1190-1205, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34534116

RESUMO

In this study, a new sulfidated nanoscale zero-valent iron (S-nZVI) supported on hydrogel (S-nZVI@H) was successfully synthesized for the removal of chromium (Cr) (VI) from groundwater. The surface morphology, dispersion phenomenon and functional groups of novel S-nZVI@H were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Box-Behnken design (BBD) optimization technology based on response surface methodology (RSM) is applied to demonstrate the influence of the interaction of S-nZVI@H dose, initial Cr(VI) concentration, contact time, and initial pH with the Cr(VI) removal efficiency. The analysis of variance results (F = 118.73, P < 0.0001, R2 = 0.9916) show that the quadratic polynomial model is significant enough to reflect the close relationship between the experimental and predicted values. The predicted optimum removal conditions are: S-nZVI@H dose 9.46 g/L, initial Cr(VI) concentration 30 mg/L, contact time 40.7 min, and initial pH 5.27, and the S-nZVI@H dose is the key factor affecting the removal of Cr(VI). The predicted value (99.76%) of Cr (VI) removal efficiency is in good agreement with the experimental value (97.75%), which verifies the validity of the quadratic polynomial model. This demonstrates that RSM with appropriate BBD can be utilized to optimize the design of experiments for removal of Cr(VI).


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Cromo/análise , Hidrogéis , Poluentes Químicos da Água/análise
19.
J Med Case Rep ; 15(1): 463, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34538261

RESUMO

BACKGROUND: In ineffective erythropoiesis, hepcidin synthesis is suppressed by erythroid regulators, namely erythroferrone and growth differentiation factor-15. For the first time, the hypothesis that iron overload in megaloblastic anemia may be related to ineffective erythropoiesis is explored by describing the kinetics of hepcidin, erythroferrone, and growth differentiation factor-15 levels in a patient diagnosed with megaloblastic anemia associated with iron overload. CASE PRESENTATION: An 81-year-old Caucasian male was admitted for fatigue. He had type-2 diabetes previously treated with metformin, ischemic cardiac insufficiency, and stage-3 chronic kidney disease. Vitiligo was observed on both hands. Biological tests revealed normocytic non-regenerative anemia associated with hemolysis, thrombocytopenia, and elevated sideremia, ferritin, and transferrin saturation levels. Megaloblastic anemia was confirmed with undetectable blood vitamin B12 and typical cytological findings like hyper-segmented neutrophils in blood and megaloblasts in bone marrow. The patient received vitamin B12 supplementation. At 3 months, biological parameters reached normal values. Hepcidin kinetics from diagnosis to 3 months inversely correlated with those of erythroferrone and growth differentiation factor-15. CONCLUSIONS: This case suggests that iron-overload mechanisms of dyserythropoietic anemias may apply to megaloblastic anemias.


Assuntos
Anemia Megaloblástica , Anemia , Sobrecarga de Ferro , Idoso de 80 Anos ou mais , Anemia Megaloblástica/diagnóstico , Anemia Megaloblástica/tratamento farmacológico , Eritropoese , Humanos , Ferro , Sobrecarga de Ferro/tratamento farmacológico , Masculino
20.
Anal Chim Acta ; 1180: 338856, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34538322

RESUMO

Single atom nanozymes (SAzymes) represent the state-of-the-art technology in nanomaterial-based catalysis, which have attracted attentions in catalysis, cancer treatment, disinfection and biosensing fields. However, numerous SAzymes suffered from low aqueous dispersion and without recognition capacity, which impeded their applications in bioanalysis. Herein, we engineered DNA onto SAzymes to obtain the DNA/SAzymes conjugates, which significantly improved the aqueous dispersion and recognition ability of SAzymes. We synthesized iron SAzymes (Fe-N-C SAzymes) as the catalytic nanomaterials, and investigated the interactions between Fe-N-C SAzymes and DNA. We compared A15, T15 and C15 adsorption of Fe-N-C SAzymes in HEPES containing 2 mM MgCl2. We found that 50 µg mL-1 Fe-N-C SAzymes produced nearly 100% A15 adsorption, 90% T15 adsorption and only 69% C15 adsorption, indicating that adenine and thymine had higher adsorption affinity on Fe-N-C SAzymes. More importantly, DNA modification did not affect the peroxidase-like activity of Fe-N-C SAzymes and the bioactivity of the adsorbed DNA. Taking the advantage of the diblock DNA with one DNA sequence (adenine) binding to Fe-N-C SAzymes and the other DNA sequence (i.e., aptamer) binding to cancer cells, we designed Apt/Fe-N-C SAzymes for colorimetric detection of cancer cells, which offered new insights for the use of SAzymes in biomedicine.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Neoplasias , Catálise , Colorimetria , DNA , Ferro , Neoplasias/diagnóstico
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