Leukocyte capture and modulation of cell-mediated immunity during human sepsis: An ex vivo study

Introduction: Promising preclinical results have been obtained with blood purification therapies as adjuvant treatment for sepsis. However, the mechanisms by which these therapies exert beneficial effects remain unclear. Some investigators have suggested that removal of activated leukocytes from the circulation might help ameliorate remote organ injury. We designed an extracorporeal hemoadsorption device capable of capturing both cytokines and leukocytes in order to test the hypothesis that leukocyte capture would alter circulating cytokine profiles and influence immunological cell-cell interactions in whole blood taken from patients with sepsis.Methods: We performed a series of ex vivo studies in 21 patients with septic shock and 12 healthy volunteers. Blood circulated for four hours in closed loops with four specially designed miniaturized extracorporeal blood purification devices including two different hemoadsorption devices and a hemofilter in order to characterize leukocyte capture and to assess the effects of leukocyte removal on inflammation and immune function. Results: Hemoadsorption was selective for removal of activated neutrophils and monocytes. Capture of these cells led to local release of certain cytokines, especially IL-8, and resulted in complex cell-cell interactions involved in cellmediated immunity. Inhibition of cell adherence reversed the cytokine release and the effects on lymphocyte function. Conclusions: Monocyte and neutrophil capture using a sorbent polymer results in upregulation of IL-8 and modulation of cell-mediated immunity. Further studies are needed to understand better these cellular interactions in order to help design better blood purification therapies. © 2013 Rimmelé et al.; licensee BioMed Central Ltd

Взаимосвязь состава и строения ферросфер скелетного и дендритного типов, выделенных из высококальциевых энергетических зол

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.This paper presents a systematic SEM–EDS study of polished sections of individual skeletal and dendritic ferrospheres in the –0.04 + 0.032 mm size fraction, isolated from fly ash from the combustion of brown coal from the Berezovskoe field. The ferrospheres are characterized by a wide range of variations in the macrocomponent composition of local areas. We have identified groups of globules whose overall composition as well as the composition of local areas on their polished sections can be represented by general equations for component concentrations: SiO2 = f(FeO), SiO2 = f(Al2O3), and CaO = f(SiO2). Such equations make it possible to identify the nature of the mineral precursors involved in the formation of the globules. FeO-rich skeletal ferrospheres with low CaO concentration originate from the thermochemical transformation of pyrite and illite associates. Skeletal and dendritic ferrospheres with monotonically increasing CaO and SiO2 concentrations are formed from pyrite and montmorillonite associates, with the participation of a melt containing quartz and decomposition products of Ca-humates of the initial coal. Skeletal and dendritic spinel ferrite crystallization is due to a magnesium aluminate spinel “seed,” resulting from the thermal transformation of illite and montmorillonite from the parent coal. The observed increase in glass phase concentration and the change from the skeletal type of crystallization to a dendritic in the ferrospheres containing ≤64 wt % FeO and ≥6.5 wt % CaO are due to the low concentration of the spinel-forming cations Fe2+ and Fe3+ in the melt and the increase in the percentage of [Fe3+O2]− and [Fe3+2O5]4− ferrite complexes with an increase in the degree of oxidation of the melt

The Composition and Structure of Ferrospheres Formed by Industrial Combustion of Ekibastuz Coal

Изучены ферросферы, полученные в виде фракций высокой чистоты из промышленной летучей золы каменного угля Экибастузского бассейна. Установлено, что главной фазой ферросфер является феррошпинель (46-49 %), в которой часть железа замещена на Al и Mg, о чем свидетельствует более низкий параметр кристаллической решетки по сравнению с магнетитом. Основная часть кремния, алюминия и значительная часть железа входят в состав аморфного вещества ферросфер, составляющего 41-42 % в изученных фракциях. Методами сканирующей электронной микроскопии и энергодисперсионной рентгеновской спектроскопии исследованы ферросферы трех типов (дендритного, блочного и дендритно- блочного строения), составляющие около 80 % изученных фракций. Установлено, что брутто-составы этих ферросфер соответствуют относительно низкоплавким (1100- 1300 ºC) составам, находящимся на границах областей кристаллизации вюстита, фаялита, железистого кордиерита, герцинита в тройной диаграмме состояния FeO–Al2O3–SiO2. Превалирующим типом глобул являются дендритные (48-63 %), которые состоят из тонких однонаправленных или разветвленных кристаллических индивидов Al, Mg-ферритовой шпинели. Дендритные кристаллы содержат Mg в 2-3 раза и Al в 1,1-2,1 раза выше по сравнению с участками аморфного вещества. Блочные ферросферы, имеющие близкий состав с дендритными глобулами, состоят из крупных высокожелезистых блоков феррошпинели, в которых содержание Mg и Al в 2-4 раза ниже, чем в межблочном аморфном веществе. Важным фактором, влияющим на строение ферросфер, выступает дисперсность их главного прекурсора – сидерита FeCO3The ferrospheres recovered from industrial fly ash of Ekibastuz coal have been studied in the form of high-purity fractions. It is found that the main phase of ferrospheres is a ferrite spinel (46-49 %), in which a part of iron is replaced by Al and Mg, as evidenced by the lower lattice parameter as compared with magnetite. A major amount of the silicon, aluminum and a substantial amount of the iron are included in amorphous substance of ferrospheres constituting 41-42 % in the studied fractions. Three types of ferrospheres (dendritic, block-like and dendritic-block structure) constituting about 80 % of the studied fractions have been investigated by SEM-EDS. It was found that the gross compositions of these ferrospheres correspond to a relatively low melting (1100-1300 ºC) composition points located on the border areas of crystallization for wustite, fayalite, ferrous cordierite and hercynite in the FeO-Al2O3-SiO2 ternary diagram. The predominant type of globules is dendritic (48-63 %), they consist of a thin unidirectional individuals or branched crystalline Al, Mg-ferrite spinel. Dendritic crystals contain Mg 2-3 times and Al 1.1-2.1 times higher compared with the amorphous regions. Block-like ferrospheres having a similar composition with dendritic globules consist of large, high-iron blocks of ferrospinels, in which Mg and Al content in the 2-4 times lower than in the interblock amorphous substance. An important factor influencing the structure ferrospheres is the dispersion of their main precursor – siderite FeCO

Состав и строение ферросфер блочного типа, выделенных из высококальциевых энергетических зол

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Polished sections of individual ferrospheres 30 to 40 μm in size, with single-block and blocky structures and a variable glass phase content, have been studied using a scanning electron microscope equipped with an energy dispersive X-ray spectrometer system. The results demonstrate that the single-block globules consist of sintered magnetite crystallites containing Al2O3, MgO, and CaO as impurities and are formed from the pyrite of the initial coal. Characteristically, the ferrospheres with a variable glass phase content differ in the composition of local areas on polished sections of the globules, which attests to inhomogeneity of the melt droplets they formed from. We have identified groups of globules whose overall composition, as well as the composition of their local areas, meet general equations for the interrelation between the concentrations of their components: SiO2 = f(FeO) and SiO2 = f(Al2O3). Comparison of the coefficients of the SiO2 = f(Al2O3) dependence for the globules with the silicate modulus (SiO2/Al2O3) of the aluminosilicate mineral components of the coal indicates that the formation of this type of globules involves pyrite–anorthite or pyrite–albite associates containing quartz impurities. The composition of the spinel ferrite in the globules produced with the participation of anorthite comprises FeO, Al2O3, MgO, and CaO in concentrations of 85–96, 1.7–10, 0.1–1.8, and 0.3–2.8 wt %, respectively. In the albite-based globules, the respective concentrations are 81–92, 0.7–5.9, 1.0–5.7, and 2.2–5.6 wt %. The crystallite size and shape are determined by the size of the local melt areas where the total concentration of spinel-forming oxides exceeds 85 wt %

Composition−Structure Relationship of Skeletal−Dendritic Ferrospheres Formed during Industrial Combustion of Lignite and Coal

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.The structure−composition relationship of skeletal−dendritic ferrospheres (FSs) isolated from fly ash from the coal and lignite combustion has been studied systematically by scanning electron microscopy (SEM) and energy-dispersive Xray spectroscopy. It is shown that illite is the aluminosilicate precursor determining the structure of globules in both cases. The formation of skeletal−dendritic globules occurs due to the “seed” of Al, Mg-ferrospinel that is formed in the thermochemical conversion of illite from initial coals. The dependence CaO = f(SiO2) that reflects the influence of glass-forming components reveals six groups of FSs, the composition of which is represented by linear regression equations. An analysis of SEM images of polished sections from six globule groups reveals that an increase in the concentration of glass-forming components in all groups is accompanied by gradual changes in the structure of globules, from the coarse-grained crystalline skeletal type to the finecrystalline dendritic type with a high content of the glass phase. The observed change in the structure is explained by expansion of the liquation region in the FeO−Fe2O3−SiO2 system, a rise in the oxidation potential, an increase in the proportion of ferrite complexes [Fe3+O2]− and [Fe23+O5]4− in high-calcium melts, and a decrease in the concentration of ferrospinel-forming Fe2+ and Fe3+ ions

Composition–Structure Relationship of Skeletal–Dendritic Ferrospheres Formed during Industrial Combustion of Lignite and Coal

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.The structure−composition relationship of skeletal−dendritic ferrospheres (FSs) isolated from fly ash from the coal and lignite combustion has been studied systematically by scanning electron microscopy (SEM) and energy-dispersive Xray spectroscopy. It is shown that illite is the aluminosilicate precursor determining the structure of globules in both cases. The formation of skeletal−dendritic globules occurs due to the “seed” of Al, Mg-ferrospinel that is formed in the thermochemical conversion of illite from initial coals. The dependence CaO = f(SiO2) that reflects the influence of glass-forming components reveals six groups of FSs, the composition of which is represented by linear regression equations. An analysis of SEM images of polished sections from six globule groups reveals that an increase in the concentration of glass-forming components in all groups is accompanied by gradual changes in the structure of globules, from the coarse-grained crystalline skeletal type to the finecrystalline dendritic type with a high content of the glass phase. The observed change in the structure is explained by expansion of the liquation region in the FeO−Fe2O3−SiO2 system, a rise in the oxidation potential, an increase in the proportion of ferrite complexes [Fe3+O2]− and [Fe23+O5]4− in high-calcium melts, and a decrease in the concentration of ferrospinel-forming Fe2+ and Fe3+ ions

The Composition and Structure of Ferrospheres Formed by Industrial Combustion of Ekibastuz Coal

Изучены ферросферы, полученные в виде фракций высокой чистоты из промышленной летучей золы каменного угля Экибастузского бассейна. Установлено, что главной фазой ферросфер является феррошпинель (46-49 %), в которой часть железа замещена на Al и Mg, о чем свидетельствует более низкий параметр кристаллической решетки по сравнению с магнетитом. Основная часть кремния, алюминия и значительная часть железа входят в состав аморфного вещества ферросфер, составляющего 41-42 % в изученных фракциях. Методами сканирующей электронной микроскопии и энергодисперсионной рентгеновской спектроскопии исследованы ферросферы трех типов (дендритного, блочного и дендритно- блочного строения), составляющие около 80 % изученных фракций. Установлено, что брутто-составы этих ферросфер соответствуют относительно низкоплавким (1100- 1300 ºC) составам, находящимся на границах областей кристаллизации вюстита, фаялита, железистого кордиерита, герцинита в тройной диаграмме состояния FeO–Al2O3–SiO2. Превалирующим типом глобул являются дендритные (48-63 %), которые состоят из тонких однонаправленных или разветвленных кристаллических индивидов Al, Mg-ферритовой шпинели. Дендритные кристаллы содержат Mg в 2-3 раза и Al в 1,1-2,1 раза выше по сравнению с участками аморфного вещества. Блочные ферросферы, имеющие близкий состав с дендритными глобулами, состоят из крупных высокожелезистых блоков феррошпинели, в которых содержание Mg и Al в 2-4 раза ниже, чем в межблочном аморфном веществе. Важным фактором, влияющим на строение ферросфер, выступает дисперсность их главного прекурсора – сидерита FeCO3The ferrospheres recovered from industrial fly ash of Ekibastuz coal have been studied in the form of high-purity fractions. It is found that the main phase of ferrospheres is a ferrite spinel (46-49 %), in which a part of iron is replaced by Al and Mg, as evidenced by the lower lattice parameter as compared with magnetite. A major amount of the silicon, aluminum and a substantial amount of the iron are included in amorphous substance of ferrospheres constituting 41-42 % in the studied fractions. Three types of ferrospheres (dendritic, block-like and dendritic-block structure) constituting about 80 % of the studied fractions have been investigated by SEM-EDS. It was found that the gross compositions of these ferrospheres correspond to a relatively low melting (1100-1300 ºC) composition points located on the border areas of crystallization for wustite, fayalite, ferrous cordierite and hercynite in the FeO-Al2O3-SiO2 ternary diagram. The predominant type of globules is dendritic (48-63 %), they consist of a thin unidirectional individuals or branched crystalline Al, Mg-ferrite spinel. Dendritic crystals contain Mg 2-3 times and Al 1.1-2.1 times higher compared with the amorphous regions. Block-like ferrospheres having a similar composition with dendritic globules consist of large, high-iron blocks of ferrospinels, in which Mg and Al content in the 2-4 times lower than in the interblock amorphous substance. An important factor influencing the structure ferrospheres is the dispersion of their main precursor – siderite FeCO

Взаимосвязь состава и строения ферросфер пластинчатого типа высококальциевых энергетических зол

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.The structure–composition relationship for polished sections of individual platelike ferrospheres in the –0.04 + 0.032 mm size fraction isolated from fly ash from the combustion of brown coal has been studied systematically by scanning electron microscopy and energy dispersive X-ray spectroscopy. We have identified groups of globules whose overall composition, as well as the composition of local areas on their polished sections, can be represented by general equations for component concentrations: CaO = f(FeO) and SiO2 = f(FeO). Analysis of the structure–composition relationship for the globules leads us to conclude that their structure is determined by transformations that occur in the CaO–FexOy system in response to an increase in its oxidation potential. It has been shown that the platelike globules containing 68–73 wt % FeO are made up of Ca2Fe2O5 and CaFe2O4 crystallites resulting from the oxidative transformation of Fe, Ca, and Mg complex humates in the parent brown coal. The ferrospheres containing 79–90 wt % FeO have a fragmentary core–shell structure, where the platelike shell consists of Ca2Fe2O5 and CaFe2O4 crystallites, and the core consists of Fe2O3 and a Ca-, Mg-, and Al-promoted magnetite. Precursors for the formation of this type of globule are pyrite associates with complex humates. It has also been demonstrated that the low concentration of aluminum and silicon oxides in the composition of the globules and the viscosity of their melt have no effect on the structure of the platelike ferrospheres

The Peculiarities of the Composition for Individual Ferrospheres of Three Morphological Types

Изучены макрокомпонентный, фазовый составы фракции ферросфер -32+20 мкм, выделенной из высококальциевых зол, и составы индивидуальных глобул разных морфологических типов. Найдено, что основными фазами фракции являются (1) феррошпинель (31 мас. %) с параметром кристаллической решетки, близким параметру стехиометрического магнетита, (2) гематит (31 мас. %) с параметрами решетки, меньшими по сравнению с параметрами стехиометрического гематита и (3) рентгеноаморфная фаза с неидентифицированными кристаллическими фазами (37 мас. %). По данным SEM-EDS, на порошках и полированных срезах показано, что основными типами индивидуальных глобул являются блочные, скелетно- дендритные и пластинчатые. Для них наблюдается однотипная поверхностная и объемная кристаллизация железосодержащих фаз, а зависимости CaO=f(Fe2O3) описываются линейными уравнениями регрессии с высокими коэффициентами корреляции. Определены отличия состава трех основных типов глобулThe major component and phase compositions of the -32+20 μm ferrosphere fraction, extracted from high-calcium fly ashes, and the compositions of individual globules of different morphological type were studied. It was found that the main phases of the fraction are (1) ferrospinel (31 wt.%) with the lattice parameter close to stoichiometric magnetite parameters, (2) hematite (31 wt.%) with lattice parameters smaller than the stoichiometric hematite parameters and (3) X-ray amorphous phase with unidentified crystalline phases (37 wt.%). According to the SEM-EDS data on powders and polished sections, it was shown that the base types of individual globules are block, skeletal-dendritic and plate types. They show the same surface and bulk crystallization for iron oxide phases and the CaO = f (Fe2O3) dependence is described by linear regression equations with high correlation coefficients. The differences of composition for the three main types of globules, were identifie

Ni2+-zeolite/ferrosphere and Ni2+-silica/ferrosphere beads for magnetic affinity separation of histidine-tagged proteins

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Magnetic Ni2+-zeolite/ferrosphere and Ni2+-silica/ferrosphere beads (Ni-ferrosphere beads – NFB) of a core–shell structure were synthesized starting from coal fly ash ferrospheres having diameters in the range of 0.063–0.050 mm. The strategy of NFB fabrication is an oriented chemical modification of the outer surface preserving the magnetic core of parent beads with the formation of micro–mesoporous coverings. Two routes of ferrosphere modification were realized, such as (i) hydrothermal treatment in an alkaline medium resulting in a NaP zeolite layer and (ii) synthesis of micro–mesoporous silica on the glass surface using conventional methods. Immobilization of Ni2+ ions in the siliceous porous shell of the magnetic beads was carried out via (i) the ion exchange of Na+ for Ni2+ in the zeolite layer or (ii) deposition of NiO clusters in the zeolite and silica pores. The final NFB were tested for affinity in magnetic separation of the histidine-tagged green fluorescent protein (GFP) directly from a cell lysate. Results pointed to the high affinity of the magnetic beads towards the protein in the presence of 10 mM EDTA. The sorption capacity of the ferrosphere-based Ni-beads with respect to GFP was in the range 1.5–5.7 mg cm−