Targeting S100A9 Reduces Neutrophil Recruitment,Inflammation and Lung Damage in Abdominal Sepsis

S100A9, a pro-inflammatory alarmin, is up-regulated in inflamed tissues. However, the role of S100A9 in regulating neutrophil activation, inflammation and lung damage in sepsis is not known. Herein, we hypothesized that blocking S100A9 function may attenuate neutrophil recruitment in septic lung injury. Male C57BL/6 mice were pretreated with the S100A9 inhibitor ABR-238901 (10 mg/kg), prior to cercal ligation and puncture (CLP). Bronchoalveolar lavage fluid (BALF) and lung tissue were harvested for analysis of neutrophil infiltration as well as edema and CXC chemokine production. Blood was collected for analysis of membrane-activated complex-1 (Mac-1) expression on neutrophils as well as CXC chemokines and IL-6 in plasma. Induction of CLP markedly increased plasma levels of S100A9. ABR-238901 decreased CLP-induced neutrophil infiltration and edema formation in the lung. In addition, inhibition of S100A9 decreased the CLP-induced up-regulation of Mac-1 on neutrophils. Administration of ABR-238901 also inhibited the CLP-induced increase of CXCL-1, CXCL-2 and IL-6 in plasma and lungs. Our results suggest that S100A9 promotes neutrophil activation and pulmonary accumulation in sepsis. Targeting S100A9 function decreased formation of CXC chemokines in circulation and lungs and attenuated sepsis-induced lung damage. These novel findings suggest that S100A9 plays an important pro-inflammatory role in sepsis and could be a useful target to protect against the excessive inflammation and lung damage associated with the disease.     

An optimized FAIRE procedure for low cell numbers in yeast

We report an optimized low‐input FAIRE‐seq (Formaldehyde‐Assisted Isolation of Regulatory Elements‐sequencing) procedure to assay chromatin accessibility from limited amounts of yeast cells. We demonstrate that the method performs well on as little as 4 mg of cells scraped directly from a few colonies. Sensitivity, specificity and reproducibility of the scaled‐down method are comparable with those of regular, higher input amounts, and allow the use of 100‐fold fewer cells than existing procedures. The method enables epigenetic analysis of chromatin structure without the need for cell multiplication of exponentially growing cells in liquid culture, thus opening the possibility of studying colony cell subpopulations, or those that can be isolated directly from environmental samples.     

Microstructure, mechanical, and anticorrosive properties of a new Ti-20Nb-10Zr-5Ta alloy based on nontoxic and nonallergenic elements

For an alloy to be suitable for use as an implant material, it must have a low specific weight and Young??s modulus, good mechanical properties that are similar to those of bone, and very good corrosion resistance and biocompatibility. In this study, we have developed a novel Ti-20Nb-10Zr-5Ta alloy that is composed of nontoxic, nonallergenic, corrosion-resistant elements. This alloy has low specific weight and Young??s modulus and good mechanical properties. It has a fine microstructure with a matrix that is mainly composed of the ?? phase and some ?? phase due to recrystallization during cooling. It shows elastoplastic behavior with a fairly linear elastic behavior and low Young??s modulus (59 GPa). In addition, its ultimate tensile strength, 0.2% yield strength, and hardness are higher than those of CP Ti, commercial Ti-6Al-4V, and similar ??-type alloys. It exhibited a very stable passive state and its electrochemical parameters and corrosion and ion release rates were better than those of CP Ti in Ringer??s solutions of different pH values that simulate the severe functional conditions of an implant; this is attributable to the beneficial influence of the alloying elements and to the better protective properties of the coated passive film.     

Control of aluminum doping of ZnO:Al thin films obtained by high-power impulse magnetron sputtering

This work reports a method used to control Al doping of ZnO thin films deposited by high-power impulse magnetron sputtering of a pure Zn target in low-pressure Ar/O₂ gas mixture. The method uses sputtering of an electrically negative biased aluminum electrode placed in the proximity of the negative glow of the magnetron discharge. Resonant laser absorption measurements of Al atom concentration in vapor phase and the X-ray Photoelectron Emission Spectroscopy measurements of Al concentration in the deposited ZnO:Al films confirm that the electrode biasing potential is the key parameter that controls the Al doping process. Optically transparent ZnO:Al films with resistivity as low as 3.6 × 10^− 3 Ω × cm have been obtained at an optimum value of Al concentration of 1.5 at.%. It has been found that the film electrical conductivity is limited by the effect of decreasing of crystalline grain size in the films with the increased Al doping concentration.     

MgB<Subscript>2</Subscript> with addition of Sb<Subscript>2</Subscript>O<Subscript>3</Subscript> obtained by spark plasma sintering technique

Superconducting bulks of MgB₂ with addition of Sb₂O₃ and Sb with different stoichiometric compositions ((MgB₂) + (Sb₂O₃) _x , x = 0.0025, 0.005, 0.015, and (MgB₂) + (Sb)_y, y = 0.01) were obtained by the Spark Plasma Sintering (SPS) technique. All added samples have high density, above 95% and critical temperature, T _c, of 38.1–38.6 K. This result and XRD data suggest that Sb does not enter the lattice of MgB₂. Impurity phases are Mg₃Sb₂, MgO, and MgB₄. The optimum addition is Sb₂O₃ for x = 0.005. This sample shows the critical current density, J _c(5 K, 0 T) = 4 × 10⁵ A/cm² and J _c(5 K, 7 T) = 6 × 10² A/cm², while the irreversibility field, H _irr (5 K, 100 A/cm²) = 8.23 T. Indicated values of J _c and H _irr are higher than for the pristine sample. The mechanism of J _c and H _irr increase in the Sb₂O₃ added samples is complex and composed of opposite effects most probably involving morphology elements, the presence of nano metric MgB₄ and the indirect influence of oxygen or oxygen and Sb. Crystallite size of MgB₂ is decreasing when Sb-based additions are introduced and the effect is stronger for the Sb-metal addition. The sample with Sb-metal addition does not improve J _c and H _irr when compared with pristine sample.     

New hydrogels based on maleilated collagen with potential applications in tissue engineering

New hydrogels based on maleic anhydride (MA) modified collagen were prepared with the aim of overcoming the high degradation rate displayed by collagen that is not otherwise chemically crosslinked. Semi-interpenetrated matrices were obtained by free radical polymerization of maleilated collagen (CM) and 2-hydroxyethyl methacrylate (HEMA) in the presence of ammonium persulfate (APS) and N,N,N′,N′-tetramethylethylenediamine (TEMED) as initiating system. The resulting matrices (CMH) had a sharp decrease in degradation, when compared to pure collagen. FTIR and H¹ NMR spectroscopies were used to confirm the incorporation of MA on the collagen peptide chains. The final composition of CMH was found to be strongly dependent by the concentration of maleilated collagen. The morphology of the hydrogels was studied by Scanning electron microscopy (SEM) and the macro-gel structure was confirmed. Water uptake of the synthetised hydrogels is influenced by both composition and the porosity of the matrices.     

Bioresponse to nanotubes: surface chemistry of carbon nanotubes impacts the growth and expression of water channel protein in tomato plants (small 15/2012)

A tomato plant grows on medium supplemented with multi-walled carbon nanotubes. The correlations between the level of aggregation, the type of functional group on the surface of applied carbon nanotubes, plant growth performance and the expression of tomato water channel protein in the cell membranes of roots exposed to multi-walled carbon nanotubes are documented and discussed by A. S. Biris, M. V. Khodakovskaya, and co-workers.     

Synthesis and hydrogen adsorption properties of a new iron based porous metal-organic framework

A new metal-organic framework [Fe₃O(OOC-C₆H₄-COO)₃(H₂O)₃]Cl·(H₂O)_x was synthesized with a specific surface area of 2823 m²/g and a lattice parameter of 88.61 Å. Isostructural with MIL-101, this compound exhibits similar hydrogen adsorption properties, with maximum adsorption capacity of 5.1wt.% H at 77 K. The adsorption enthalpy of hydrogen for MIL-101 and ITIM-1 (MIL-101Fe) at zero coverage was calculated for a wide temperature range of 77 K ÷ 324 K, considering corrections for the variation of hydrogen gas entropy with the temperature. The resulted adsorption enthalpy is 9.4 kJ/mol for MIL-101, in excellent agreement with the value reported in literature from microcalorimetric measurements, and a value of 10.4 kJ/mol at zero coverage was obtained for ITIM-1 (MIL-101Fe).     

Plasma parameters of argon and argon/molecular gas mixture plasmas produced in microwave discharge

The experimental results and their analysis are presented concerning electron density and temperature of the microwave discharge plasma (power range 100–500 W) produced in Ar gas and Ar–N₂ and Ar–N₂–NO gas mixture at the total pressure of 0.5 Torr. The triple probe method was primarily used in order to set-up a direct and on-time technique to measure electron temperature in complex plasma. The results were compared with those obtained using a cylindrical probe mounted in a circuit with reference electrode. Each probe was made of tungsten wires of 0.5 mm diameter and 3 mm in length each. When plasma contains only one maxwellian group of electrons, within the experimental errors, both the probes systems get comparable value of plasma parameters. When the characteristic of cylindrical probe shows two groups of thermal electrons within the microwave plasma the triple probe may show always results concerning one group but of which temperature depends on the ratio of the densities of those two groups of electrons.     

Studies on the structure and gas sensing properties of nickel–cobalt ferrite thin films prepared by spin coating

The influence of Co²⁺ ions content on structure and sensing properties of Ni_1−xCo_xFe₂O₄ (x = 0.25, 0.5, 0.75) thin films deposited on glass substrates by spin coating is presented. Structural characterization evidenced thin films with cubic spinel structures and morphologies dependent on cobalt content. Repartition of cations in spinel tetrahedral and octahedral sites was determined and was found that the presence of Co²⁺ ions in octahedral sites favor the formation of Fe²⁺ species. The sensitivity to some reducing vapor gases (acetone, liquefied petroleum gas LPG, ethyl alcohol and methyl alcohol) was investigated and was found that thin films with x = 0.75 exhibit high sensitivity to ethyl alcohol and thin films with x = 0.25 have high sensitivity to acetone. This sensitivity largely depends on the temperature and test gas concentration and was related to the Fe²⁺ species formed in octahedral sites.