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1.
Curr Opin Anaesthesiol ; 34(3): 352-356, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33935184

RESUMEN

PURPOSE OF REVIEW: In the past years, patient blood management (PBM) has evolved to improve patient's care and safety. Anemia is one of the most common medical diseases in the world and is an independent risk factor for morbidity and mortality. Iron deficiency is the main cause for anemia and constitutes a potentially preventable condition with a great impact on surgical outcome. However, preoperative anemia management is not yet established in most hospitals. Changing workflows and re-thinking is challenging. Numerous published studies confirmed the positive effect of preoperative anemia diagnosis and treatment recently. RECENT FINDINGS: Iron supplementation in iron-deficient anemic (IDA) patients reduce the need for allogenic blood transfusion thereby improving perioperative outcome. SUMMARY: Since the introduction of PBM programs, important movements towards early detection and therapy of preoperative anemia have been observed. However, preoperative anemia management is not implemented on a large scale as many healthcare professionals are not aware of the most recent findings in the field. Preoperative anemia management, particularly iron supplementation in IDA patients, has proven to be highly effective and has a tremendous effect on patient safety and outcome.


Asunto(s)
Anemia , Anemia/diagnóstico , Anemia/epidemiología , Anemia/etiología , Transfusión Sanguínea , Humanos , Hierro , Cuidados Preoperatorios , Factores de Riesgo
2.
Bioresour Technol ; 332: 125086, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33838451

RESUMEN

An iron-based composite adsorbent with biochar as the support was prepared by coprecipitation and the sol-gel method. Both single-iron-based modified biochar without doping with other metals and iron-based modified biochar doped with multiple metals (Ce, Cu, Co, Mn) were synthesised. The adsorption kinetics were analysed, and temperature-programmed desorption measurements were performed to reveal the inherent difference in mechanism between the oxidation and adsorption of Hg0 by the modified biochar and to elucidate the key mechanism of Hg0 removal. The results show that the removal of Hg0 by the modified biochar mainly includes adsorption and oxidation processes. The adsorption process is divided into two stages, external and internal mass transfer, both of which occur via multilayer adsorption. HgO and Hg-OM are the main forms of Hg0 present on the modified biochar surface. Doped metal oxides can play a synergistic role in enhancing the mercury removal performance of the modified biochar.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Hierro , Contaminantes Químicos del Agua/análisis
3.
Environ Sci Technol ; 55(9): 6299-6308, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33843193

RESUMEN

The application of nanosized zerovalent iron (nZVI) for reductive immobilization of selenite (Se(IV)) or selenate (Se(VI)) alone has been extensively investigated. However, as the predominant species, Se(IV) and Se(VI) usually coexist in the environment. Thus, it is essential to remove both species simultaneously in the solution by nZVI. Negligible Se(VI) removal (∼7%) by nZVI was observed in the absence of Se(IV). In contrast, the Se(VI) was completely removed in the presence of Se(IV), and the removal rate and electron selectivity of Se(VI) increased from 0.12 ± 0.01 to 0.29 ± 0.02 h-1 and from 1% to 4.5%, respectively, as the Se(IV) concentration increased from 0.05 to 0.20 mM. Se(IV) was rapidly removed by nZVI, and Se(VI) exerted minor influence on Se(IV) removal. Se(IV) promoted the generation of corrosion products that were mainly composed of magnetite (26%) and lepidocrocite (67%) based on the Fe K-edge XANES spectra and k3-weighted EXAFS analysis. Fe(II) released during the Se(IV) reduction was not the main reductant for Se(VI) but accelerated the transformation of F(0) to magnetite and lepidocrocite. The formation of lepidocrocite contributed to the enrichment of Se(VI) on the nZVI surface, and magnetite promoted electron transfer from Fe(0) to Se(VI). This study demonstrated that Se(IV) acted as an oxidant to activate nZVI, thus improving the reactivity of nZVI toward Se(VI), which displays a potential application of nZVI in the remediation of Se(IV)- and Se(VI)-containing water.


Asunto(s)
Hierro , Contaminantes Químicos del Agua , Adsorción , Corrosión , Ácido Selénico , Ácido Selenioso
4.
Environ Sci Technol ; 55(9): 5878-5886, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33899483

RESUMEN

Lead contamination in soils and sediments is a major threat to water quality. In surface and near-surface environments, Pb is not redox active; however, common Pb hosts, including Fe(III)-(hydr)oxides and sulfides, dissolve and precipitate as redox conditions change. Dissolution of Pb hosts may release Pb to porewater, leading to spikes in dissolved Pb concentrations and potential transport into surface or groundwater. Here, we examine the impacts of hydrologically coupled redox transitions on Pb partitioning in contaminated floodplain soils. We find that the affinity of Pb for particulate organic matter (POM), inclusive of mineral-associated organic matter, ensures that across redox transitions Pb is retained in the solid phase, despite host-phase (Fe(III)-(hydr)oxide and sulfide) dissolution. As seasonal hydrologic dynamics shift porewater redox conditions, Pb-bearing Fe(III)-(hydr)oxides (Pb-HFO) and sulfides (PbS) are dissolved and (re)precipitated. However, despite these shifts in redox conditions and associated host-phase transformations, Pb retention on POM, coupled with the formation of PbS and Pb-HFO, maintains dissolved Pb concentrations below 17 µg L-1. Importantly, the predominance of Pb adsorbed on POM alongside low dissolved Pb concentrations indicates that Pb released from HFO and PbS is retained by POM. Thus, despite host-phase dissolution during redox transitions, partitioning of Pb to the aqueous phase is minimal and, therefore, transport of dissolved Pb is unlikely.


Asunto(s)
Hierro , Plomo , Plomo/análisis , Oxidación-Reducción , Material Particulado , Suelo , Sulfuros
5.
Water Sci Technol ; 83(8): 2025-2037, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33905370

RESUMEN

The jarosite crystallization and new extractant system for extractant 7101 was used to separate iron and extract vanadium from titanium white waste liquid (TWWL). The influence factors and mechanisms of crystallization and solvent extraction were investigated and analyzed using SEM-EDS, XRD, FT-IR, solution thermodynamic theory and extraction isothermal curve. More than 97% of iron was precipitated with the following conditions: potassium chlorate 15 g/L, pH value of 1.6, temperature of 95 °C and time of 90 min, in which the crystallization product was jarosite with a purity of 99.5%; the pH value of the solution decreased after precipitation. The extraction efficiency of vanadium reached 88.6% with 10% Fe, 5% Al(III) but less for Mg(II), K(I) and Na(I) under the conditions X7101 of 0.5, pH value of 2.0, time of 4 min and stirring speed of 40 r/min. The extraction of metal ions occurred in the order V(V) > Fe(III) > Al(III) > Mg(II) > K(I). Vanadium minimally existed as H2V10O284- at pH 2.0, and the functional groups NH and C-N contributed to vanadium extraction using the extractant 7101. Four stages extraction and three stages of re-extraction were predicated by McCable-Thiele plots.


Asunto(s)
Hierro , Vanadio , Cristalización , Compuestos Férricos , Solventes , Espectroscopía Infrarroja por Transformada de Fourier , Sulfatos , Titanio
6.
Int J Mol Sci ; 22(5)2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33800732

RESUMEN

Matriptase-2, a serine protease expressed in hepatocytes, is a negative regulator of hepcidin expression. The purpose of the study was to investigate the interaction of matriptase-2 with hemojuvelin protein in vivo. Mice lacking the matriptase-2 proteolytic activity (mask mice) display decreased content of hemojuvelin protein. Vice versa, the absence of hemojuvelin results in decreased liver content of matriptase-2, indicating that the two proteins interact. To further characterize the role of matriptase-2, we investigated iron metabolism in mask mice fed experimental diets. Administration of iron-enriched diet increased liver iron stores as well as hepcidin expression. Treatment of iron-overloaded mask mice with erythropoietin increased hemoglobin and hematocrit, indicating that the response to erythropoietin is intact in mask mice. Feeding of an iron-deficient diet to mask mice significantly increased spleen weight as well as the splenic content of erythroferrone and transferrin receptor proteins, indicating stress erythropoiesis. Liver hepcidin expression was decreased; expression of Id1 was not changed. Overall, the results suggest a complex interaction between matriptase-2 and hemojuvelin, and demonstrate that hepcidin can to some extent be regulated even in the absence of matriptase-2 proteolytic activity.


Asunto(s)
Proteínas Ligadas a GPI/fisiología , Proteína de la Hemocromatosis/fisiología , Sobrecarga de Hierro/metabolismo , Proteínas de la Membrana/fisiología , Serina Endopeptidasas/fisiología , Animales , Proteína Morfogenética Ósea 6/biosíntesis , Proteína Morfogenética Ósea 6/genética , Eritropoyetina/farmacología , Femenino , Proteínas Ligadas a GPI/biosíntesis , Proteínas Ligadas a GPI/deficiencia , Proteínas Ligadas a GPI/genética , Regulación de la Expresión Génica/efectos de los fármacos , Proteína de la Hemocromatosis/biosíntesis , Proteína de la Hemocromatosis/deficiencia , Proteína de la Hemocromatosis/genética , Hepcidinas/biosíntesis , Hepcidinas/genética , Proteína 1 Inhibidora de la Diferenciación/biosíntesis , Proteína 1 Inhibidora de la Diferenciación/genética , Hierro/deficiencia , Hierro en la Dieta/farmacología , Hígado/metabolismo , Masculino , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Especificidad de Órganos , Regiones Promotoras Genéticas/genética , Dominios Proteicos , Proteínas Recombinantes/metabolismo , Serina Endopeptidasas/deficiencia , Serina Endopeptidasas/genética , Bazo/metabolismo
7.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33802163

RESUMEN

Bacteria access iron, a key nutrient, by producing siderophores or using siderophores produced by other microorganisms. The pathogen Pseudomonas aeruginosa produces two siderophores but is also able to pirate enterobactin (ENT), the siderophore produced by Escherichia coli. ENT-Fe complexes are imported across the outer membrane of P. aeruginosa by the two outer membrane transporters PfeA and PirA. Iron is released from ENT in the P. aeruginosa periplasm by hydrolysis of ENT by the esterase PfeE. We show here that pfeE gene deletion renders P. aeruginosa unable to grow in the presence of ENT because it is unable to access iron via this siderophore. Two-species co-cultures under iron-restricted conditions show that P. aeruginosa strongly represses the growth of E. coli as long it is able to produce its own siderophores. Both strains are present in similar proportions in the culture as long as the siderophore-deficient P. aeruginosa strain is able to use ENT produced by E. coli to access iron. If pfeE is deleted, E. coli has the upper hand in the culture and P. aeruginosa growth is repressed. Overall, these data show that PfeE is the Achilles' heel of P. aeruginosa in communities with bacteria producing ENT.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Esterasas/metabolismo , Hierro/metabolismo , Pseudomonas aeruginosa/metabolismo , Proteínas Portadoras/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Esterasas/genética , Pseudomonas aeruginosa/genética
8.
Klin Lab Diagn ; 66(4): 205-209, 2021 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-33878240

RESUMEN

The number of obese pregnant women increases annually and reaches 20-30%. The metabolism of hormones and minerals changes in the presence of a large amount of adipose tissue in the body of a pregnant woman, which leads to a number of obstetric and perinatal problems. The aim of the work is to study and compare the influence of the gestational process on the indicators of iron and copper metabolism in the blood serum of women with normal body weight and women with obesity. In the blood serum of 125 women of reproductive age, the content of hemoglobin, iron, transferrin, ferritin, copper and ceruloplasmin was determined. The influence of pregnancy on the indicators of iron and copper metabolism in the blood serum of women was revealed. Pregnancy in women with normal body weight increases the content of transferrin and ceruloplasmin. Correlation of ceruloplasmin and ferritin content with body mass index of obese pregnant women was revealed. In pregnancy with concomitant obesity, hyperferritinemia is formed with a reduced content of hemoglobin and serum iron. Knowledge of the indicators of iron and copper metabolism is necessary to optimize the observation of pregnant women, effective prevention and prediction of obstetric and perinatal complications.


Asunto(s)
Cobre , Hierro , Cobre/metabolismo , Femenino , Ferritinas , Humanos , Peso Corporal Ideal , Hierro/metabolismo , Obesidad , Embarazo
9.
Int J Mol Sci ; 22(6)2021 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-33809032

RESUMEN

Iron is essential for multiple bacterial processes and is thus required for host colonization and infection. The antimicrobial activity of multiple iron chelators and gallium-based therapies against different bacterial species has been characterized in preclinical studies. In this review, we provide a synthesis of studies characterizing the antimicrobial activity of the major classes of iron chelators (hydroxamates, aminocarboxylates and hydroxypyridinones) and gallium compounds. Special emphasis is placed on recent in-vitro and in-vivo studies with the novel iron chelator DIBI. Limitations associated with iron chelation and gallium-based therapies are presented, with emphasis on limitations of preclinical models, lack of understanding regarding mechanisms of action, and potential host toxicity. Collectively, these studies demonstrate potential for iron chelators and gallium to be used as antimicrobial agents, particularly in combination with existing antibiotics. Additional studies are needed in order to characterize the activity of these compounds under physiologic conditions and address potential limitations associated with their clinical use as antimicrobial agents.


Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Galio/uso terapéutico , Quelantes del Hierro/uso terapéutico , Hierro/metabolismo , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Bacterias/efectos de los fármacos , Bacterias/patogenicidad , Infecciones Bacterianas/microbiología , Farmacorresistencia Bacteriana , Humanos , Ácidos Hidroxámicos/química , Ácidos Hidroxámicos/uso terapéutico , Hierro/química , Quelantes del Hierro/química , Pruebas de Sensibilidad Microbiana
10.
Front Immunol ; 12: 598601, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33815361

RESUMEN

Cryptococcal meningitis (CM) is the leading cause of mortality among patients infected with human immunodeficiency virus (HIV). Although treatment strategies for CM are continually being developed, the mortality rate is still high. Therefore, we need to explore more therapeutic strategies that are aimed at hindering its pathogenic mechanism. In the field of CM, several studies have observed rapid iron accumulation and lipid peroxidation within the brain, all of which are hallmarks of ferroptosis, which is a type of programmed cell death that is characterized by iron dependence and lipid peroxidation. In recent years, many studies have confirmed the involvement of ferroptosis in many diseases, including infectious diseases such as Mycobacterium tuberculosis infection and coronavirus disease-2019 (COVID-19). Furthermore, ferroptosis is considered as immunogenic and pro-inflammatory as the ferroptotic cells release damage-associated molecular pattern molecules (DAMPs) and alarmin, both of which regulate immunity and pro-inflammatory activity. Hence, we hypothesize that there might be a relationship between this unique cell death modality and CM. Herein, we review the evidence of ferroptosis in CM and consider the hypothesis that ferroptotic cell death may be involved in the cell death of CM.


Asunto(s)
/metabolismo , Ferroptosis , Hierro/metabolismo , Peroxidación de Lípido , Meningitis Criptocócica/metabolismo , Tuberculosis/metabolismo , /inmunología , Ferroptosis/inmunología , Glutatión/metabolismo , Humanos , Inflamación/inmunología , Metabolismo de los Lípidos , Meningitis Criptocócica/inmunología , Meningitis Criptocócica/patología , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Tuberculosis/inmunología , Tuberculosis/patología
11.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804198

RESUMEN

Body iron levels are regulated by hepcidin, a liver-derived peptide that exerts its function by controlling the presence of ferroportin (FPN), the sole cellular iron exporter, on the cell surface. Hepcidin binding leads to FPN internalization and degradation, thereby inhibiting iron release, in particular from iron-absorbing duodenal cells and macrophages involved in iron recycling. Disruption in this regulatory mechanism results in a variety of disorders associated with iron-deficiency or overload. In recent years, increasing evidence has emerged to indicate that, in addition to its role in systemic iron metabolism, FPN may play an important function in local iron control, such that its dysregulation may lead to tissue damage despite unaltered systemic iron homeostasis. In this review, we focus on recent discoveries to discuss the role of FPN-mediated iron export in the microenvironment under both physiological and pathological conditions.


Asunto(s)
Proteínas de Transporte de Catión/genética , Microambiente Celular/genética , Hepcidinas/genética , Hierro/metabolismo , Proteínas de Transporte de Catión/metabolismo , Hepcidinas/metabolismo , Homeostasis/genética , Humanos , Hígado/metabolismo , Macrófagos/metabolismo , Unión Proteica
12.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-33805837

RESUMEN

For over 50 years, patients with drug-sensitive and drug-resistant tuberculosis have undergone long, arduous, and complex treatment processes with several antimicrobials. With the prevalence of drug-resistant strains on the rise and new therapies for tuberculosis urgently required, we assessed whether manipulating iron levels in macrophages infected with mycobacteria offered some insight into improving current antimicrobials that are used to treat drug-resistant tuberculosis. We investigated if the iron chelator, desferrioxamine, can support the function of human macrophages treated with an array of second-line antimicrobials, including moxifloxacin, bedaquiline, amikacin, clofazimine, linezolid and cycloserine. Primary human monocyte-derived macrophages were infected with Bacillus Calmette-Guérin (BCG), which is pyrazinamide-resistant, and concomitantly treated for 5 days with desferrioxamine in combination with each one of the second-line tuberculosis antimicrobials. Our data indicate that desferrioxamine used as an adjunctive treatment to bedaquiline significantly reduced the bacterial load in human macrophages infected with BCG. Our findings also reveal a link between enhanced bactericidal activity and increases in specific cytokines, as the addition of desferrioxamine increased levels of IFN-γ, IL-6, and IL-1ß in BCG-infected human monocyte-derived macrophages (hMDMs) treated with bedaquiline. These results provide insight, and an in vitro proof-of-concept, that iron chelators may prove an effective adjunctive therapy in combination with current tuberculosis antimicrobials.


Asunto(s)
Antituberculosos/farmacología , Deferoxamina/farmacología , Diarilquinolinas/farmacología , Quelantes del Hierro/farmacología , Hierro/metabolismo , Macrófagos/efectos de los fármacos , Mycobacterium bovis/efectos de los fármacos , Amicacina/farmacología , Carga Bacteriana/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Clofazimina/farmacología , Cicloserina/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Sinergismo Farmacológico , Expresión Génica , Humanos , Interferón gamma/genética , Interferón gamma/inmunología , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Linezolid/farmacología , Macrófagos/inmunología , Macrófagos/microbiología , Pruebas de Sensibilidad Microbiana , Moxifloxacino/farmacología , Mycobacterium bovis/crecimiento & desarrollo , Mycobacterium bovis/metabolismo , Cultivo Primario de Células , Pirazinamida/farmacología
13.
Biomed Khim ; 67(2): 162-168, 2021 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-33860774

RESUMEN

The antioxidant effect of dinitrosyl iron complexes (DNICs) was studied in various model systems. DNICs with glutathione ligands effectively inhibited Cu2+-induced peroxidation of low density lipoproteins (LDL). The antioxidant effect of DNICs with phosphate ligands and free reduced glutathione (GSH) was less pronounced. In addition, DNICs with glutathione suppressed the formation of reactive oxygen species during co-oxidation of lecithin liposomes and glucose. Free radical oxidation in this system was induced with a lipophilic azo initiator and evaluated by luminol-dependent chemiluminescence. NO sharply stimulated chemiluminescence during co-oxidation of glucose and liposomes, thus suggesting the formation of potent oxidants under these conditions. Glutathione DNICs scavenge the superoxide radical anion generated in the xanthine-xanthine oxidase system. Superoxide production was assessed by lucigenin-dependent chemiluminescence and electron paramagnetic resonance (EPR) spectroscopy. Chemiluminescence revealed the dose-dependent character of antiradical effect of glutathione DNICs; moreover, these complexes turned out to be more efficient than GSH. EPR spectra of the adducts of the DEPMPO spin trap with free radicals suggest that the interaction of glutathione DNICs and superoxide does not result in the formation of the thiyl radical of glutathione. Here we propose a mechanism of the antioxidant action of glutathione DNICs, suggesting that unstable intermediate complexes are formed upon their interaction with superoxide or lipid radicals. Further, as a result of intramolecular rearrangement, these intermediates decompose without the free radical as the by-products.


Asunto(s)
Antioxidantes , Óxidos de Nitrógeno , Antioxidantes/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Glutatión , Hierro , Superóxidos
14.
Bioresour Technol ; 331: 125025, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33812745

RESUMEN

Adding ferric ions (Fe3+) in catholyte can enhance performance of microbial fuel cells (MFCs). This work adopted biocathode with enriched Fe2+ oxidizing microflora to perform in situ Fe2+ oxidization so the MFC could operate with prolonged period with increased cell open circuit voltage (1037 mV) and maximum power density (71.8 Wm-3 at 154 Am-3) but with minimal needs for iron replenishment. The Fe2+-oxidizing microflora was very effective so the Fe3+/Fe2+ could reach high ratio, which was composed of Acidithiobacillus (73.8%), Acidiphilium (12.1%), Mycobacterium (6.92%), Sulfobacillus (2.66%), Ochrobactrum (1.30%), Alicyclobacillus (0.82%), and other minor species. The membrane transport and cell replication were shown to be their most important metabolic activities. The formation of jarosite and hydronium jarosite by Fe3+ and sulfate led to loss of iron ions, which should be minimized in operation.


Asunto(s)
Acidithiobacillus , Fuentes de Energía Bioeléctrica , Hierro , Oxidación-Reducción , Temperatura
15.
Nat Commun ; 12(1): 2069, 2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33824308

RESUMEN

The oxygenation of early Earth's atmosphere during the Great Oxidation Event, is generally accepted to have been caused by oceanic Cyanobacterial oxygenic photosynthesis. Recent studies suggest that Fe(II) toxicity delayed the Cyanobacterial expansion necessary for the GOE. This study investigates the effects of Fe(II) on two Cyanobacteria, Pseudanabaena sp. PCC7367 and Synechococcus sp. PCC7336, in a simulated shallow-water marine Archean environment. A similar Fe(II) toxicity response was observed as reported for closed batch cultures. This toxicity was not observed in cultures provided with continuous gaseous exchange that showed significantly shorter doubling times than the closed-culture system, even with repeated nocturnal addition of Fe(II) for 12 days. The green rust (GR) formed under high Fe(II) conditions, was not found to be directly toxic to Pseudanabaena sp. PCC7367. In summary, we present evidence of diurnal Fe cycling in a simulated shallow-water marine environment for two ancestral strains of Cyanobacteria, with increased O2 production under anoxic conditions.


Asunto(s)
Organismos Acuáticos/metabolismo , Archaea/metabolismo , Ritmo Circadiano , Hierro/metabolismo , Oxígeno/metabolismo , Organismos Acuáticos/efectos de los fármacos , Organismos Acuáticos/crecimiento & desarrollo , Archaea/efectos de los fármacos , Archaea/crecimiento & desarrollo , Atmósfera , Clorofila A/metabolismo , Hierro/toxicidad , Modelos Biológicos , Agua de Mar
16.
Water Sci Technol ; 83(7): 1578-1590, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33843744

RESUMEN

Antibiotic resistance genes (ARGs), as a new type of environmental pollutant that threaten human health, have been detected in the effluent of sewage treatment systems. In this study, the removal from water of ARGs, 16S rRNA, class 1 integron (intI1), and dissolved organic carbon (DOC) were investigated using processes combining nano-iron (nFe), ultrasound (US), activated persulfate (PS) and ultrafiltration (UF). The oxidation mechanism was also studied. The results showed that both nFe and US activation could improve the oxidative effect of PS, and the effect of nFe was better than that of US. Compared with PS-UF, nFe/PS-UF and US/PS-UF significantly enhanced the removal of various ARGs and DOC. nFe/PS-UF was the most effective treatment, reducing cell-associated and cell-free ARGs by 1.74-3.14-log and 1.00-2.61-log, respectively, while removing 30% of DOC. Pre-oxidation methods using PS, nFe/PS, and US/PS significantly enhanced the efficacy of UF for removing DOC with molecular weights above 50 kDa and below 10 kDa, but the removal of DOC between 10 and 50 kDa decreased. The free radicals SO4·- and ·OH were shown to participate in the process of ARGs oxidation.


Asunto(s)
Antibacterianos , Ultrafiltración , Antibacterianos/farmacología , Farmacorresistencia Microbiana , Hierro , ARN Ribosómico 16S , Aguas Residuales
17.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804129

RESUMEN

SARS-CoV-2 currently lacks effective first-line drug treatment. We present promising data from in silico docking studies of new Methisazone compounds (modified with calcium, Ca; iron, Fe; magnesium, Mg; manganese, Mn; or zinc, Zn) designed to bind more strongly to key proteins involved in replication of SARS-CoV-2. In this in silico molecular docking study, we investigated the inhibiting role of Methisazone and the modified drugs against SARS-CoV-2 proteins: ribonucleic acid (RNA)-dependent RNA polymerase (RdRp), spike protein, papain-like protease (PlPr), and main protease (MPro). We found that the highest binding interactions were found with the spike protein (6VYB), with the highest overall binding being observed with Mn-bound Methisazone at -8.3 kcal/mol, followed by Zn and Ca at -8.0 kcal/mol, and Fe and Mg at -7.9 kcal/mol. We also found that the metal-modified Methisazone had higher affinity for PlPr and MPro. In addition, we identified multiple binding pockets that could be singly or multiply occupied on all proteins tested. The best binding energy was with Mn-Methisazone versus spike protein, and the largest cumulative increases in binding energies were found with PlPr. We suggest that further studies are warranted to identify whether these compounds may be effective for treatment and/or prophylaxis.


Asunto(s)
Antivirales/química , Metales/química , Metisazona/química , Simulación del Acoplamiento Molecular , /química , Antivirales/metabolismo , Calcio/química , Calcio/metabolismo , /metabolismo , /metabolismo , /metabolismo , Diseño de Fármacos , Humanos , Hierro/química , Hierro/metabolismo , Magnesio/química , Magnesio/metabolismo , Manganeso/química , Manganeso/metabolismo , Metales/metabolismo , Metisazona/metabolismo , Modelos Moleculares , Simulación de Dinámica Molecular , Unión Proteica , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Zinc/química , Zinc/metabolismo
18.
Mymensingh Med J ; 30(2): 337-342, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33830111

RESUMEN

This cross-sectional analytical study was conducted in the department of Paediatrics, Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh from March 2017 to August 2018 to assess the pattern of serum iron profile and red cell indices in children with severe acute malnutrition. Seventy children having severe acute malnutrition were compared with 70 age matched children those had normal growth. Age range of the studied children was 6 months to 59 completed months. Male was found predominant (54.3%) in both study group and comparison group. Mean serum iron, serum ferritin, serum total iron binding capacity and transferrin saturation in severely malnourished children were 45.3±19.3µg/dl, 26.5±20.0ng/ml, 246.3±47.5µg/dl and 16.4±2.0% respectively which were significantly lower than that of healthy children (p<0.05). Mean Hb level in children with severe acute malnutrition was found 8.3±1.6gm/dl which was also found significantly lower than that of normal children (p<0.05). Anaemia was found in all (100%) severely malnourished children compared to 25.7% of children in comparison group. Mean MCV, MCH and MCHC in children with severe acute malnutrition was found 71.7±13.5fl, 24.0±5.8pg and 31.4±4.0gm/dl respectively which were significantly lower than that of comparison group (p<0.05). Serum iron profile and red cell indices should be routinely done in severely malnourished children for early intervention and management of iron deficiency anaemia.


Asunto(s)
Anemia Ferropénica , Desnutrición Aguda Severa , Anemia Ferropénica/epidemiología , Bangladesh/epidemiología , Niño , Estudios Transversales , Índices de Eritrocitos , Hemoglobinas/análisis , Humanos , Lactante , Hierro , Masculino , Desnutrición Aguda Severa/complicaciones , Desnutrición Aguda Severa/epidemiología
19.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806756

RESUMEN

The popularity of fasting and restricted food intake is increasing. While the body's adaptability to dietary insufficiency is crucial for health, molecular mechanisms of adaptive changes are not well understood. Here, we compared the effects of fasting and exercise on the expression of leukocyte genes and proteins involved in the storage, export, and acquisition of iron, an essential element with physiological roles. Healthy men participated in the study (age, 30-70 years; body weight, 60-100 kg; body mass index, 20-29.9 kg/m2). The participants performed an exercise test with a gradually increasing intensity until the individual maximum exercise capacity was reached, before and after 8-d fast. Blood samples were collected before, immediately after, and 3 h after exercise. Gene expression was analyzed by reverse-transcription quantitative polymerase chain reaction and protein levels were analyzed by immunobloting. Eight days of total starvation diet affected the body composition and decreased exercise capacity. Further, fasting decreased the expression of genes associated with iron storage and export, and increased the expression of genes involved in iron acquisition. Conversely, only PCBP2 protein increased after fasting; however, an upward trend was apparent for all proteins. In conclusion, the body adapts to starvation by adjusting iron economy.


Asunto(s)
Proteínas de Transporte de Catión/genética , Ayuno , Regulación de la Expresión Génica , Hierro/metabolismo , Leucocitos/metabolismo , Adulto , Proteínas de Transporte de Catión/metabolismo , Ayuno/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Estrés Oxidativo , Factores Sexuales , Factores de Tiempo
20.
Int J Mol Sci ; 22(7)2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33807459

RESUMEN

BACKGROUND: Oral iron supplementation causes gastrointestinal side effects. Short-term alterations in dietary iron exacerbate inflammation and alter the gut microbiota, in murine models of colitis. Patients typically take supplements for months. We investigated the impact of long-term changes in dietary iron on colitis and the microbiome in mice. METHODS: We fed mice chow containing differing levels of iron, reflecting deficient (100 ppm), normal (200 ppm), and supplemented (400 ppm) intake for up to 9 weeks, both in absence and presence of dextran sodium sulphate (DSS)-induced chronic colitis. We also induced acute colitis in mice taking these diets for 8 weeks. Impact was assessed (i) clinically and histologically, and (ii) by sequencing the V4 region of 16S rRNA. RESULTS: In mice with long-term changes, the iron-deficient diet was associated with greater weight loss and histological inflammation in the acute colitis model. Chronic colitis was not influenced by altering dietary iron however there was a change in the microbiome in DSS-treated mice consuming 100 ppm and 400 ppm iron diets, and control mice consuming the 400 ppm iron diet. Proteobacteria levels increased significantly, and Bacteroidetes levels decreased, in the 400 ppm iron DSS group at day-63 compared to baseline. CONCLUSIONS: Long-term dietary iron alterations affect gut microbiota signatures but do not exacerbate chronic colitis, however acute colitis is exacerbated by such dietary changes. More work is needed to understand the impact of iron supplementation on IBD. The change in the microbiome, in patients with colitis, may arise from the increased luminal iron and not simply from colitis.


Asunto(s)
Colitis/metabolismo , Sobrecarga de Hierro/fisiopatología , Hierro/metabolismo , Anemia Ferropénica , Animales , Bacterias/genética , Colitis/fisiopatología , Colon/patología , Sulfato de Dextran/farmacología , Dieta , Suplementos Dietéticos/efectos adversos , Modelos Animales de Enfermedad , Disbiosis/etiología , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/genética , Inflamación , Enfermedades Inflamatorias del Intestino/patología , Hierro en la Dieta/efectos adversos , Ratones , Ratones Endogámicos C57BL , Microbiota , ARN Ribosómico 16S/genética
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