Hydrogen Desorption Below 150 °C in MgH₂–TiH₂ Composite Nanoparticles: Equilibrium and Kinetic Properties

Reversible hydrogen sorption coupled with the MgH₂ ↔ Mg phase transformation was achieved in the remarkably low 340–425 K temperature range using MgH₂–TiH₂ composite nanoparticles obtained by reactive gas-phase condensation of Mg–Ti vapors under He/H₂ atmosphere. The equilibrium pressures determined by in situ measurements at low temperature were slightly above those predicted using enthalpy Δ<i>H</i> and entropy Δ<i>S</i> of bulk magnesium. A single van’t Hoff fit over a range extended up to 550 K yields the thermodynamic parameters Δ<i>H</i> = 68.1 ± 0.9 kJ/molH₂ and Δ<i>S</i> = 119 ± 2 J/(K·molH₂) for hydride decomposition. A desorption rate of 0.18 wt % H₂/min was measured at <i>T</i> = 423 K and p­(H₂) ≈ 1 mbar, i.e., close to equilibrium, without using a Pd catalysts. The nanoparticles displayed a small absorption–desorption pressure hysteresis even at low temperatures. We critically discuss the influence exerted by nanostructural features such as interface free energy, elastic clamping, and phase mixing at the single nanoparticle level on equilibrium and kinetic properties of hydrogen sorption

Impact of Anion Exchange Ionomers on the Electrocatalytic Performance for the Oxygen Reduction Reaction of B‑N Co-doped Carbon Quantum Dots on Activated Carbon

Composite electrocatalytic electrodes made from B-N co-doped carbon quantum dots (CQD) and various anion exchange ionomers (AEI) are studied for the oxygen reduction reaction (ORR) in alkaline solutions. The quantity and positions of dopants in CQD, prepared by hydrothermal synthesis, are analyzed by various spectroscopies, including 11B NMR spectroscopy that evidenced boronic acid at edge sites. The AEI are synthesized with various backbones, including more hydrophilic polysulfone, hydrophobic poly(alkylene biphenyl), and poly(2,6-dimethyl-1,4-phenylene oxide) with intermediate hydrophilicity; the functional groups are trimethylammonium moieties grafted on long (LC) or short (SC) side chains. The CQD/AEI ink is drop-casted on activated carbon paper, and the samples are fixed on a rotating disk electrode and studied in three-electrode configuration in oxygen-saturated 0.1 M KOH. The onset potentials are among the best in the literature (Eonset ≈ 0.94 V vs RHE). The highest electrocatalytic activity is observed for electrodes containing AEI with long side chains; the sample containing PPO LC attains excellent ORR currents approaching that of benchmark Pt/C cloth. The electrocatalytic performances are discussed in view of the many relevant AEI parameters, including hydrophilicity, oxygen permeability, catalyst dispersivity, and ionic conductivity

Additional file 1: Figures S1A, S1B, and S1C. of PML-RAR alpha induces the downmodulation of HHEX: a key event responsible for the induction of an angiogenetic response

Figure S1A Analysis of HHEX (top panel) and VEGF-A (middle panel) reported in 176 primary AMLs on the TCGA platform. The HHEX/VEGF-A ratio is reported in the bottom panel. Figure S1B Correlation between HHEX and VEGF-A levels observed in 18 primary APLs in the present study (p = 0.0484) and in 16 primary APLs in the TCGA data (p = 0.0284). Figure S1C Correlation between HHEX and VEGF-A levels observed in 18 primary APLs (p = 00484) and in 20 primary M5 AMLs in the TCGA data (p = 0.0174). (ZIP 689 kb

In hypoxia, TM9SF4 is a direct target gene of HIF-1α in leukemic cells.

<p>(A) HIF-1α DNA binding site (HRE) identified on TM9SF4 partial promoter sequence is shown. (B) Chromatin immunoprecipitation (ChIP) experiments were performed by using protein extracts of U937 cells cultured in hypoxia (panels 1% O₂), as compared to normoxia (panels 21% O₂), immunoprecipitated with the anti(α)-HIF-1α or with an unrelated α-cAbl antibodies, or no antibody (No Ab), and analyzed by PCR amplification of the TM9SF4 region surrounding the HRE site (Prom-TM9SF4) or a GAPDH coding region used as an internal control. Input: PCR on 0.02% of total chromatin. One representative experiment of three is shown. (C) Promoter activity assays were performed first (<i>left panels</i>) by using TM9SF4 upstream DNA sequence subcloned in the pGL3Basic promoterless luciferase vector (Prom-TM9SF4) and transfected into 293T cells in the presence (white bars) or absence (black) of a HIF-1α expression vector, as compared to empty pGL3Basic vector (vector); then (<i>right panels</i>) by using Prom-TM9SF4, or the same region with a mutated HRE binding site (Prom- MutTM9SF4), cloned in the pGL3Promoter reporter vector containing a minimal promoter, and transfected with or without a HIF-1α expression vector. Data of luciferase activity detected are mean ± S.E.M. values of 3 independents experiments.</p

TM9SF4 is a new molecule involved in cell adhesion of leukemic cells.

<p>(A, B) Adhesion assays show that the number of adherent U937 cells to fibronectin (Fn)-coated plates under hypoxic condition (1% O₂) is significantly decreased compared to normoxic conditions (21% O₂). (C, D) In normoxia, adhesion assays show that the number of adherent TM9SF4-siRNAs transfected U937 cells to fibronectin (Fn)-coated plates (TM9SF4-siRNA) is significantly lower than the number of adherent control-siRNA transfected U937 cells (c-siRNA). (E; F) Knockdown of TM9SF4 expression in TM9SF4-siRNA transfected U937 cells (TM9SF4-siRNA) was controlled by Western blot (E) and flow cytometry (F) analysis of TM9SF4 protein expression compared to control-siRNAs transfected U937 cells (c-siRNA). (A, C) Pictures of one representative experiment of adhesion assays are shown. (B, D, F) Data are presented as the mean of six independent experiments (n = 6) ± SEM; **, *** are p<0.01, p<0.001 respectively. (E) One representative experiment out of three is shown; actin is shown as internal control.</p

TM9SF4 is expressed during Mo and G proliferation and differentiation of HPCs, but is overexpressed in AMLs.

<p>(A, B) Real time PCR analysis of TM9SF4 mRNA expression during selective Mo and G proliferation and differentiation of CD34⁺ HPCs (day 0). (C-F) Analysis of TM9SF4 protein expression is shown by flow cytometry (C, D) and Western blot (E, F) analysis in Mo and G differentiating HPCs. (G) Real time PCR analysis of TM9SF4 mRNA expression in primary leukemic cells of AMLs pertaining from M0 to M5 subtypes of FAB classification, as compared to normal CD34⁺ HPCs. (A—D) The results of three independent experiments (mean ± SEM values) are shown; n.s. is for not significant; significance *, **, *** are p<0.05, p<0.01, p<0.001 respectively and as compared to day 0; °, °° are p<0.05, p<0.01 respectively and between indicated days. (A, B, G) A.U. is for arbitrary units. (C, D) MFI is for Mean Fluorescence Intensity. (E, F) One representative experiment out of three is shown; actin is an internal control. (F) 293T is for protein extract prepared from 293T(pcDNA3.1/TM9SF4) overexpressing cells used as a positive control of TM9SF4 protein expression. (G) Results are presented as scatter plot. Mean is indicated; significance *, ⁺ and *** are p<0.05 and p<0.001 respectively.</p

Hypoxia that activates HIF-1α, downmodulates TM9SF4 expression in leukemic cells.

<p>(A, B) Cell growth analysis of U937 (A) and HL-60 (B) cells grown 48 hours in hypoxia (1% O₂), as compared to normoxia (21% O₂). (C, D) Western blot analysis of HIF-1α nuclear protein expression in U937 (C) and HL-60 (D) cells cultured in hypoxia (1% O₂), as compared to normoxia (21% O₂). (E, F) Real time PCR analysis of TM9SF4 mRNA expression in U937 (E) and HL-60 (F) cells in hypoxia, as compared to normoxia. (G—J) TM9SF4 protein expression levels were analyzed by Western blot (G, H) and flow cytometry (I, J) analysis in U937 (G, I) and HL-60 (H, J) cells in hypoxia, as compared to normoxia. (A, B, E, F, I, J) The results of three independent experiments (mean ± SEM values) are shown; *, ** are p<0.05, p<0.01 respectively. (C, D, G, H) One representative experiment out of three is shown; nucleolin is an internal control of nuclear protein extracts (C, D); actin is an internal control of total protein extracts (G, H); 293T is for 293T(pcDNA3.1/TM9SF4) overexpressing cells, used as a positive control of TM9SF4 protein expression (G). (E, F) A.U. is for arbitrary units.</p

In hypoxia, HIF-1α is a direct transcriptional repressor of TM9SF4 in leukemic cells.

<p>(A) Performed under hypoxic condition (1% O₂), knockdown of HIF-1α in U937 and HL-60 cells by using HIF-1α small interfering RNAs (HIF-1α-siRNA), as compared to control siRNA (c-siRNA), was controlled at protein level by Western blot analysis in U937 cells (left panel) and at mRNA level by real time PCR analysis in HL-60 cells (right panel). (B-D) TM9SF4 expression in U937(HIF-1α-siRNA) and HL-60(HIF-1α-siRNA) cells, as compared to U937(c-siRNA) and HL-60(c-siRNA) control cells, cultured in hypoxia (1% O₂) compared to normoxia (N), was analyzed at mRNA level by real time PCR analysis (B) and at protein level by western blot (C) and flow cytometry (D) analysis in U937 and HL-60 cells. (A HL-60, B, D) The results of three independent experiments (mean ± SEM values) are shown; *, ** are p<0.05, p<0.01 respectively. (A U937, C) One representative experiment out of three is shown; nucleolin is used as an internal control of U937 nuclear protein extracts; actin is shown as internal control of total protein extracts (C).</p

TM9SF4 decreases during vitamin D3-induced Mo differentiation of U937 cells, but increases during ATRA-induced G differentiation of HL-60 cells.

<p>(A) Flow cytometry analysis of specific Mo markers CD11b and CD14 expression was performed from day 0 to 5 (d5) in U937 cells treated with vitamin D3 (VITD3) to induce Mo differentiation, as compared to untreated U937 control cells (d0). (B) Real time PCR analysis of TM9SF4 mRNA expression during VITD3- induced Mo differentiation of U937 cells. (C, D) Western blot (C) and flow cytometry analysis (D) of TM9SF4 protein expression in VITD3-treated U937 cells, as compared to untreated control U937 cells (d0). (E) Flow cytometry analysis of G markers CD11b and CD54 was performed from day 0 to 5 (d5) in HL-60 treated with all trans retinoic acid (ATRA) for G differentiation, as compared to untreated HL-60 control cells (d0). (F) Real time PCR analysis of TM9SF4 mRNA expression during ATRA- induced G differentiation of HL-60 cells. (G, H) Western blot (G) and flow cytometry analysis (H) of TM9SF4 protein expression in ATRA-treated HL-60 cells, as compared to untreated control HL-60 cells (d0). (A, B, D, E, F, H) The results of three independent experiments (mean ±SEM values) are shown; *, **, *** are p<0.05, p<0.01, p<0.001 respectively; n.s. is for not significant. (A, D, E, H) MFI is for Mean Fluorescence intensity. (B, F) A.U. is for arbitrary units. (C, G) One representative experiment out of three is shown; actin is shown as an internal control; (C) 293T is for 293T(pcDNA3.1/TM9SF4) overexpressing cells used as a positive control of TM9SF4 protein expression.</p

Synergistic induction of cell death by salinomycin and TRAIL.

<p>(A) T98G and U251 cell lines have been grown for various periods of time (indicated in each panel) in the absence (NT) or in the presence of 1.2 µM salinomycin (Sal) added alone or in combination with increasing doses of TRAIL (from 10 to 200 ng/ml). At the end of the incubation the percentage of viable cells was determined by trypan blue exclusion test. The data represent the mean ± SEM values observed in three separate experiments. *** different from control (NT) at significance level <i>p</i><0.001. (B) T98G and U251 cells have been grown in the presence of increasing concentrations of TRAIL (from 10 to 200 ng/ml) either in the absence (Sal 0) or in the presence of 1.2 µM salinomycin (Sal 1.2 µM). The results are plotted assuming the 100% value of cell vitality for either Sal 0 or Sal 1.2 µM, in the absence of TRAIL. The data represent mean values observed in three separate experiments. * and ** different from control (NT) at significance level <i>p</i><0.05 and <i>p</i><0.01, respectively. (C) A172 cell line has been grown for 48 h in the absence (NT) or in the presence of increasing concentrations of TRAIL (from 10 to 100 ng/ml), 1.2 µM Salinomycin (Sal) added alone or in the presence of increasing TRAIL concentrations. TB10 cell line has been grown in the absence (NT) or in the presence of increasing concentrations of Salinomycin (Sal, from 0.6 to 10 µM) or in the presence of 50 ng/ml TRAIL (TRAIL) added alone or in combination with increasing concentrations of Salinomycin. At the end of the incubation period the percentage of viable cells was determined by trypan blue exclusion test. The data represent the mean±SEM values observed in three separate experiments. (D) The A172 and TB10 cells were grown as reported in C and the results were plotted assuming the 100% value of cell viability for either Sal 0 or Sal 1.2 µM (A172 cells) or for either TRAIL 0 or TRAIL 50 ng/ml (TB10 cells). The data represent mean values observed in three separate experiments.</p