Repressing iron overload ameliorates central poststroke pain via the Hdac2-Kv1.2 axis in a rat model of hemorrhagic stroke

Thalamic hemorrhage can lead to the development of central post-stroke pain.Changes in histone acetylation levels,which are regulated by histone deacetylases,affect the excitability of neurons surrounding the hemorrhagic area.However,the regulato ry mechanism of histone deacetylases in central post-stroke pain remains unclea r.Here,we show that iron overload leads to an increase in histone deacetylase 2expression in damaged ventral posterolateral nucleus neurons.Inhibiting this increase restored histone H3 acetylation in the Kcna2 promoter region of the voltage-dependent potassium(Kv)channel subunit gene in a rat model of central post-stroke pain,thereby increasing Kcna2expression and relieving central pain.However,in the absence of nerve injury,increasing histone deacetylase 2 expression decreased Kcna2expression,decreased Kv current,increased the excitability of neurons in the ventral posterolateral nucleus area,and led to neuropathic pain symptoms.Moreover,treatment with the iron chelator deferiprone effectively reduced iron overload in the ventral posterolateral nucleus after intracerebral hemorrhage,reversed histone deacetylase 2 upregulation and Kv1.2 downregulation,and alleviated mechanical hypersensitivity in central post-stroke pain rats.These results suggest that histone deacetylase 2 upregulation and Kv1.2 downregulation,mediated by iron overload,are important factors in central post-stroke pain pathogenesis and co uld se rve as new to rgets for central poststroke pain treatment.

Solubility of iron(Ⅲ) and nickel(Ⅱ) acetylacetonates in supercritical carbon dioxide

As a common precursor for supercritical CO_(2)(scCO_(2))deposition techniques,solubility data of organometallic complexes in scCO_(2)is crucial for the preparation of nanocomposites.Recently,metal acetylacetonates have shown great potential for the preparation of single-atom catalytic materials.In this study,the solubilities of iron(Ⅲ)acetylacetonate(Fe(acac)3)and nickel(Ⅱ)acetylacetonate(Ni(acac)2)were measured at the temperature from 313.15 to 333.15 K and in the pressure range of 9.5–25.2 MPa to accumulate new solubility data.Solubility was measured using a static weight loss method.The semi-empirical models proposed by Chrastil and Sung et al.were used to correlate the solubility data of Fe(acac)3 and Ni(acac)2.The equations obtained can be used to predict the solubility of the same system in the experimental range.

Synthesis, characterization, and stability of iron (III) complex ions possessing phenanthroline-based ligands

It has previously been demonstrated that phenanthroline-based ligands used to make gold metallotherapuetics have the ability to exhibit cytotoxicity when not coordinated to the metal center. In an effort to help assess the mechanism by which these ligands may cause tumor cell death, iron binding and removal experiments have been considered. The close linkage between cell proliferation and intracellular iron concentrations suggest that iron deprivation strategies may be a mechanism involved in inhibiting tumor cell growth. With the creation of iron (III) phen complexes, the iron binding abilities of three polypyridal ligands [1,10-phenanthroline (phen), 2,9-dimethyl-1, 10-phenanthroline (methylphen), and 2,9-di-sec-butyl-1, 10-phenanthroline (sec-butylphen)] can be tested via a competition reaction with a known iron chelator. Therefore, iron (III) complexes possessing all three ligands were synthesized. Initial mass spectrometric and infrared absorption data indicate that iron (III) tetrachloride complex ions with protonated phen ligands (RphenH+) were formed: [phenH][FeCl4], [methylphenH][FeCl4], [sec-butylphenH][FeCl4]. UV-vis spectroscopy was used to monitor the stability of the complex ions, and it was found that the sec-butylpheniron complex was more stable than the phen and methylphen analogues. This was based on the observation that free ligand was observed immediately upon the addition of EDTA to the [phenH][FeCl4] and [methylphenH] [FeCl4] complex ions.

AXIAL LIGATION AND ESR STUDIES OF 2－BENZENIMI DAZOLETHIOL －LINKED IRON（III） PORPHYRINS

The axial ligation properties of 2-benzenimidazolethiol-linked iron(III)porphyrins are presented along with their ESR studies

Structural Analysis of Magnesium-Aluminium Hydrotalcites Modified with Iron III Obtained by Hydroxide Precipitation Method

Hydrotalcite-type anionic clays are a group of important materials used in adsorption processes, mainly for organic pollutants removal due the layered double hydroxide structure. The layer-interlayer interactions provide a structural memory even after dehydration and dehydroxylation process, since a very stable interlayer anions are part of material composition, like the carbonate one. A limited numbers of trivalent modifier cations can replace the aluminium cation due the ionic radii mismatch or oxidation state restrictions. Transition metal cations can replace the aluminium one in octahedral site of hydroxide lamellas in order to improve the adsorptive behaviors. In this work, we have investigate three compositions of carbonated magnesium-aluminium hydrotalcite with dif-ferent iron (III) contents through the co-precipitation method at pH 11 and aging step at 60°C for 6 hours. Thermal analysis was performed aiming the determination of the hydration water and hydroxyl amounts in dried precipitate samples, taking in account the results obtained for X-ray diffractometry, infrared spectroscopy, and nitrogen adsorption-desorption characterization for several thermally treated samples. All of synthesized samples showed high surface areas, even for high temperature of thermal treatment. The co-substitution with iron (III) reduced the temperature of dehydration and dehydroxylation process, but the co-substitution at 5 mol% provides other desirables characteristics, like a more amount of rhombohedral HDL phase and higher porosity, even after the thermal treatment at 500°C for 4 hours. This result makes that composition very applicable as a reusable adsorbent material in order to removal several types of micro-pollutant compounds in aqueous media.

Kinetics on Thermal Decomposition of Iron(III) Complexes of 1,2-Bis(Imino-4’-Antipyrinyl)Ethane with Varying Counter Anions

A comparative thermal decomposition kinetic investigation on Fe(III) complexes of a antipyrine Schiff base ligand, 1,2-Bis(imino-4’-antipyrinyl)ethane (GA)), with varying counter anions viz. CIO4-, NO3-, SCN-, Cl-, and Br-, has been done by thermogravimetric analysis by using Coats-Redfern equation. The kinetic parameters like activation energy (E), pre-exponential factor (A) and entropy of activation (ΔS) were quantified. On comparing the various kinetic parameters, lower activation energy was observed in second stage as compared to first thermal decomposition stage. The same trend has been observed for pre-exponential factor (A) and entropy of activation (ΔS). The present results show that the starting materials having higher activation energy (E), are more stable than the intermediate products, however;the intermediate products possess well-ordered chemical structure due to their highly negative entropy of activation (ΔS) values. The present investigation proves that the counter anions play an important role on the thermal decomposition kinetics of the complexes.

Iron(Ⅲ) phthalocyanine chloride-catalyzed oxidation–aromatization of α,β-unsaturated ketones with hydrazine hydrate: Synthesis of 3,5-disubstituted 1H-pyrazoles

We have developed an iron（III） phthalocyanine chloride‐catalyzed oxidation–aromatization ofα,β‐unsaturated ketones with hydrazine hydrate. Various 3,5‐disubstituted 1H‐pyrazoles were obtained in good to excellent yields. This method offers several advantages, including room‐tem‐perature conditions, short reaction time, high yields, simple work‐up procedure, and use of air as an oxidant. The catalyst can be recovered and reused five times without loss of activity.

Separation and Concentration of Indium from Leaching Solution Containing Indium, Antimony and Iron Ions

Processing conditions of effectively separating indium from the leaching solution of a smelting antimony slag were studied. For the leaching solution containing indium and antimony and iron ions, indium was separated by extracting with HDEHP kerosine solution, washing antimony and iron ions with oxalic acid solution and stripping indium with a dilute solution of hydrochloric acid. InCl 3 solution with purity above 90% is obtained. Indium can be enriched through a circulation of stripping with a dilute HCl solution. The concentration of InCl 3 solution is about 25～30 g/L.

锑氧化菌Pseudomonas sp.AO-1的分离鉴定及其对Sb(III)的氧化性能

采用抗性筛选法从锡矿山筛选出一株锑氧化菌,并利用分子生物学技术对其进行鉴定;考察了其氧化Sb()Ⅲ的性能和氧化次生矿物的特征.结果表明:锑氧化菌属于假单胞菌属(Pseudomonas),将其命名为Pseudomonas sp.AO-1(简称:AO-1);影响AO-1氧化Sb(Ⅲ)的因素主要有溶液pH值、溶解氧和铁锰氧化物(单质铁、FeCl_(3)和MnO_(2))等;AO-1在好氧和缺氧条件下均能氧化Sb(Ⅲ),好氧氧化Sb(Ⅲ)的米门常数Km和最大氧化速率Vmax值分别为393.05µmol/L和0.271µmol/(L·min),体现了较强的锑氧化性;AO-1和铁锰氧化物的耦合作用能促进Sb(Ⅲ)的氧化,且铁锰氧化物促进AO-1氧化Sb(Ⅲ)的速率依次为:FeCl_(3)>MnO_(2)>单质铁;AO-1和铁锰氧化物耦合氧化Sb(Ⅲ)生成含Sb(Ⅴ)的次生矿物,次生矿物会加速Sb(Ⅲ)的氧化以及影响锑在环境中的迁移转化.菌株AO-1的锑氧化性能良好,对于锑的生物化学转化和土壤微生物修复的应用有重要意义.

Topotactically constructed nickel-iron(oxy)hydroxide with abundant in-situ produced high-valent iron species for efficient water oxidation

The low efficiency of oxygen evolution reaction(OER) is regarded as one of the major roadblocks for metal-air batteries and water electrolysis.Herein,a high-performance OER catalyst of NiFe_(0.2)(oxy)hydroxide(NiFe_(0.2)-O_(x)H_(y)) was developed through topotactic transformation of a Prussian blue analogue in an alkaline solution,which exhibits a low overpotential of only 263 mV to reach a current density of 10 mA cm^(-2) and a small Tafel slope of 35 mV dec-1.Ex-situ/operando Raman spectroscopy results indicated that the phase structure of NiFe_(0.2)-O_(x)H_(y) was irreversibly transformed from the type of α-Ni(OH)_(2) to γ-NiOOH with applying an anodic potential,while ex-situ/operando 57Fe Mossbauer spectroscopic studies evidenced the in-situ production of abundant high-valent iron species under OER conditions,which effectively promoted the OER catalysis.Our work elucidates that the amount of high-valent iron species in-situ produced in the NiFe(oxy)hydroxide has a positive correlation with its water oxidation reaction performance,which further deepens the understanding of the mechanism of NiFe-based electrocatalysts.

Sorption Kinetic of Arsenate as Water Contaminant on Zero Valent Iron

This study investigates the sorption of arsenate from water using zero-valent iron ZVI as sorbent. Batch experiments were carried out to study the sorption kinetics of arsenate under different concentrations of arsenate varies from 0.5 to 200 mg/l. A kinetic model was considered to describe the arsenates sorption on ZVI material. The kinetics of the arsenate sorption processes were described by the Langmuir kinetic model. The sorption capacity increases with high initial concentration which obtained the maximum sorption 2.1 mg/g at 200 mg/l of arsenate initial concentration. The results show that the rapid initial sorption rates of arsenate were occurred at the beginning of experiments running time, followed by a slower removal that gradually approaches an equilibrium condition. The data from laboratory batch experiments were used to verify the simulation results of the kinetic model resulting in good agreement between measured and modeled results. The results indicate that ZVI could be employed as sorbent materials to enhance the sorption processes and increase the removal rate of arsenate from water.

Effect of iron transformation on Acidithiobacillus ferrooxidans bio-leaching of clay vanadium residue

The acid bio-leaching process of vanadium extraction from clay vanadium water-leached residue was studied and the effect of the performance of iron transformation was investigated.Acidithiobacillus ferrooxidans affects the dissolution of vanadium through the catalytic effect on Fe^3+/Fe^2+couple and material exchange.The passivation of iron settling correlates with ferrous ion content in bio-leaching solution.In medium containing A.ferrooxidans and Fe(Ⅲ),the increment in Fe(Ⅱ)concentration leads to the formation of jarosite,generating a decline in vanadium extraction efficiency.Analysis of cyclic voltammetry shows that Fe(Ⅱ)ion is apt to be oxidized and translated into precipitate by A.ferrooxidans,which strongly adsorbed to the surface of the residue.Fe(Ⅲ)ion promotes the vanadium extraction due to its oxidizing activity.Admixing A.ferrooxidans to Fe(Ⅲ)medium elevates the reduction of low valence state vanadium and facilitates the exchange of substance between minerals and solution.This motivates 3.8%and 21.8%increments in recovery ratio and leaching rate of vanadium compared to the Fe(Ⅲ)exclusive use,respectively.Moreover,Fe(Ⅱ)ion impacts vanadium extraction slightly in sterile medium but negatively influences vanadium leaching in the presence of bacteria.

Chitosan—The Application of a Natural Polymer against Iron Hydroxide Deposition

As a consequence of mining, heavy metal ions can be exposed to the environment hence contaminate ground water and surface water amongst others. The natural polymer chitosan was proved to be an excellent adsorber material for the effective removal of iron and sulfate ions in batch as well as in column experiments. The adsorption behavior of iron ions, as well as sulfate ions was investigated by utilizing chitosan flakes as a natural adsorbent. The removal was studied using adsorbance measurements, SEM and SEM-EDX. The adsorption capacity of chitosan was determined at different times. The received adsorption capacities for iron ions were very promising with a maximum adsorption capacity of 85 mg/g and a rate of separation of 100%. The maximum adsorption capacity obtained for sulfate ions was 188.8 mg/g and a rate of 80%.

IRON IONS INCREASE THE THERMOSTABILITY OF PHYCOCYANIN OF SPIRULINA MAXIMA

A spectral method to investigate the effect of Fe3+, Fe2+ on the thermostability ofphycocyanin (PC) of Spirulina maxima showed that iron ions prevent decrease of visible light absorbanceand fluorescence intensity of PC. Increase in denaturation temperature caused by Fe3+ was observed bythe micro - differential scanning calorimetric method. All results showed iron ions maintain the aggrega-tion stability of the PC. The absorption spectrum of phycocyanobilin (PCB, a prosthetic group of PC) withFe3+ in chloroform was quite different from that of free PCB.

Structure and Coordination Investigation of Iron-ion Tinting Principle in Ferreous Glass

The tinting phenomena of iron oxide contained glasses were studied from aspects of the electronic configuration, the iron ions coordination fields and the ions structure in glass. Several iron ion tinting forms at different redox or COD (chemical oxygen demand) conditions and their influential factors were given necessary explanations. The results reveal that the Fe^(3+)-O-Fe^(2+) structure is the real tinting reason of iron involved glasses, whereas the Si^(4+)-O-Fe^(3+) and Si^(4+)-O-Fe^(2+) formulations modify the glass colours. Under oxidizing melting condition, the amount of 4/6-coordinated Fe^(3+) increases and makes the glass colour yellowish. Conversely, reducing melting condition makes the 6-coordinated Fe^(2+) increased and gives much blue tint to the glass. The conventional tank furnace melting the very strong reducing condition, which is of high COD glass batch, is not suitable. The high ratio of ferrous/ferric in glass can be obtained with a new refining technology which contains no or little amount of refining agent.

Dynamic scaling behavior of iron nitride thin films prepared by magnetron sputtering and ion implantation

Under far from equilibrium conditions, the formation mechanism of solid can be studied in terms of the dynamic scaling theory. The roughness and dynamic scaling behavior of the Fe-N thin films were studied by atomic force microscopy and grazing incidence X-ray scattering. The results indicate that the roughness of the surface increases with increasing sputtering time during the course of magnetron sputtering, and the surface exhibits a fractal characteristic. While the Fe-N films prepared by compound technology—combining magnetron sputtering with plasma based ion implantation are not in agreement with the fractal theory.

Ion Probe Study of Silicate Inclusions from Colomera （IIE） Iron Meteorite： the Rare Earth Element Perspective

Coupled with a petrographical study, I carried out an ion probe study of rare earth element microdistributions in mineral phases of silicate inclusions from the Colomera ⅡE iron meteorite. Most mineral grains have homogeneous REEs, but show considerable inter-grain variations by a factor of 2 to 100. The whole rock REE abundances for Colomera, estimated by combining REE data with modal abundances, are relatively LREE-enriched with REEs of -10'CI, which suggest that Colomera silicates were highly differentiated and might represent a low degree partial melt (-10%) of a chondritic source. REE geochemistry of Colomera silicate inclusions points to an origin that involves differentiation, dynamic mixing, remelting, reduction, recrystallization, and subsequent rapid cooling near the surface of a planetary body.

Amplified Detection of Iron Ion Based on Plasmon Enhanced Fluorescence and Subsequently Fluorescence Quenching

A facile and rapid approach for detecting low concentration of iron ion(Fe3+) with improved sensitivity was developed on the basis of plasmon enhanced fluorescence and subsequently amplified fluorescence quenching.Au1Ag4@Si O2 nanoparticles were synthesized and dispersed into fluorescein isothiocyanate(FITC) solution. The fluorescence of the FITC solution was improved due to plasmon enhanced fluorescence. However, efficient fluorescence quenching of the FITC/Au1Ag4@Si O2 solution was subsequently achieved when Fe3+, with a concentration ranging from17 n M to 3.4 l M, was added into the FITC/Au1Ag4@Si O2 solution, whereas almost no fluorescence quenching was observed for pure FITC solution under the same condition. FITC/Au1Ag4@Si O2 solution shows a better sensitivity for detecting low concentration of Fe3+compared to pure FITC solution. The quantized limit of detection toward Fe3+was improved from 4.6 l M for pure FITC solution to 20 n M for FITC/Au1Ag4@Si O2 solution.

Removing Iron Ions Contaminants from Groundwater Using Modified Nano-Hydroxyapatite by Nano Manganese Oxide

In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), Elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = ?51 KJ/mol, and ΔS = ?142 (KJ/mol)) for the adsorption process were also calculated and discussed.

Sensitivity of Barley Varieties to Aluminum Ions: Separately Effects and Combine with Iron Ions

Differences in the barley varieties have been revealed from tolerance to iron (Fe) and aluminum (Al) ions as well as to their combined effect. Received results allowed to separate barley variety into some (three) groups: the first—Al-tolerant varieties, the second—Al-sensitive ones and third—moderately resistant variety. The increased concentration of Fe had practically no effect on biometric (seed germination energy) and cytogenetics (frequency of chromosome aberrations and mitotic index) parameters as compared to the reference values. At the same time, iron ion significantly reduces the phytotoxic effect for Al-tolerant varieties in case of these elements jointly presented in solution.