Investigation of New Alkali Bismuth Oxosulfates and Oxophosphates with Original Topologies of Oxo-Centered Units

Two new alkali bismuth oxosulfates, [Bi₁₂O₁₅]­Li₂(SO₄)₄ (<b>I</b>) and [Bi₇K₂O₈]­K­(SO₄)₄ (<b>II</b>), have been synthesized by heating a mixture of Bi₂O₃, CuSO₄­5H₂O, and A₂CO₃ (A = Li, K), and characterized by single crystal XRD, transmission electron microscopy, and multiphoton SHG and IR spectroscopy. In the above formula the [Bi_<i>x</i>O_<i>y</i>] subunits denote the 3D-porous (<b>I</b>) or 1D-columnar (<b>II</b>) polycationic host-lattice formed of edge-sharing OBi₄ or O­(Bi,K)₄ oxocenterd tetrahedra. The SO₄^2– groups and alkali ions are arranged into channels in the interstices leading to original opened crystal structures for these two first reported alkali oxo-bismuth sulfates. The strong adaptability of the oxocentered framework is demonstrated by the possibility of preparing single crystals of [Bi_8.73K_0.27O₈]­K_1.54(PO₄)₄ (<b>III</b>) whose crystal structure is similar to those of <b>II</b> with disorder between OBi₄ and O­(Bi₃,K) tetrahedra and different channel occupancy due to the aliovalent replacement of SO₄^2– for PO₄^3–

Cryo-correlative fluorescence and scanning transmission electron microscopy (STEM) of cells in the different stages of apoptosis.

<p>For each stage, four images of the same cell from a single 80 nm-thick ultrathin cryo section are shown. Fluorescence imaging of H2B-GFP in the ultrathin cryo sections (first and second panels showing fluorescence intensity on a gray scale, and after application of a rainbow RGB look-up table, respectively) made it possible to analyze chromatin distribution and nucleus shape, to identify each stage of apoptosis. The cells characterized by fluorescence imaging were then imaged by STEM (third panel). Due to a strong natural electron contrast and good ultrastructural preservation, the compartments in the cytoplasm are easily identified. Merging of the fluorescence and STEM images recorded at the same magnification (last panel) is required for a clear identification of chromatin clumps before the targeted elemental analysis of condensed chromatin and nucleoplasm. The scale bar represents 1 μm.</p

Nuclear shape and the condensation and disposition of chromatin were sufficient to identify cells i) entering apoptosis (ST 1), ii) in the course of apoptosis (ST 2 to ST 5) and iii) not engaged in apoptosis (ST 0).

<p>We confirmed this identification by TMRE staining, the localization of cytochrome-<i>c</i> (in the mitochondria, cytosol or nucleus) and the presence of activated CASP-3 and cleaved PARP.</p

Targeted quantification of Na⁺, Cl^-, S and Mg²⁺ in the cytosol, mitochondria, condensed chromatin and nucleoplasm.

<p>Concentration of elements/ions (Na⁺, Cl^-, S and Mg²⁺) were determined by energy dispersive X-ray spectrometry in the cytosol, mitochondria, condensed chromatin and nucleoplasm of each of the following: i) control cells, ii) cells in the various stages of apoptosis (ST 1 to ST 5) and iii) cells in the ST 0 stage. Results, in mmol/L, are given as means ±SEM. (<i>n</i> = 3; 3 to 83 different cells per stage).</p

Simultaneous 3D localization of cytochrome-<i>c</i> (Cc) and H2B-GFP showing Cc redistribution during specific stages of apoptosis.

<p>Anti-cytochrome-<i>c</i> antibody binding was imaged on fixed HeLa cells stably expressing H2B-GFP after the induction of apoptosis by 500 ng/mL AMD, for 7h and 15 minutes. Four images are shown for the same cell, at a given stage. On the first image, differential interference contrast (DIC) shows the shape of the cell, nucleus and nucleolus. The second image is an optical section passing through the middle of the nucleus showing the merge of images for Cc (red) and H2B-GFP (green). The third image is a 3D surface rendering of Cc alone (red). The last image is a simultaneous 3D transparent volume rendering of both Cc (red) and H2B-GFP (green). The scale bar represents 10 μm.</p

pH Controlled Pathway and Systematic Hydrothermal Phase Diagram for Elaboration of Synthetic Lead Nickel Selenites

The PbO–NiO–SeO₂ ternary system was fully studied using constant hydrothermal conditions at 473 K. It yields the establishment of the corresponding phase diagram using a systematic assignment of reaction products by both powder and single-crystal X-ray diffraction. It leads to the preparation of three novel lead nickel selenites, α-PbNi­(SeO₃)₂ (<b>I</b>), β-PbNi­(SeO₃)₂ (<b>II</b>), and PbNi₂(SeO₂OH)₂(SeO₃)₂ (<b>III</b>), and one novel lead cobalt selenite, α-PbCo­(SeO₃)₂ (<b>IV</b>), which have been structurally characterized. The crystal structures of the α-forms <b>I</b>, <b>IV</b>, and <b>III</b> are based on a 3D complex nickel selenite frameworks, whereas the β-PbNi­(SeO₃)₂ modification (<b>II</b>) consists of nickel selenite sheets stacked in a noncentrosymmetric structure, second-harmonic generation active. The pH value of the starting solution was shown to play an essential role in the reactive processes. Magnetic measurements of <b>I</b>, <b>III</b>, and <b>IV</b> are discussed

Targeted quantification of water and of N, P and K⁺ in the cytosol, mitochondria, condensed chromatin and nucleoplasm.

<p>Water percentage was calculated by STEM imaging and the concentration of element/ions (N, P and K⁺) was calculated by energy dispersive X-ray spectrometry in the cytosol, mitochondria, condensed chromatin and nucleoplasm of each of the following: i) control cells, ii) cells in various stages of apoptosis (ST 1 to ST 5 stages) and iii) cells in the ST 0 stage. Results, in mmol/L, are given as means ±SEM (<i>n</i> = 3; 3 to 83 different cells per stage).</p

Simultaneous imaging of cell shape, mitochondrial potential and nuclear modifications at the onset and during the various stages of apoptosis.

<p>HeLa cells stably expressing H2B-GFP were stained with TMRE to study mitochondrial polarization. Simultaneous time-lapse confocal imaging of cell shape (DIC), TMRE and H2B-GFP was performed by two-photon excitation every five minutes for 7 hours and 15 minutes after the induction of apoptosis by the addition of 500 ng/mL AMD. (A) Traces for TMRE intensity (red line, relative to value reached at time 0.91 h) and nuclear volume (green line, relative to value at time 0 h) in a representative cell (cell #9 on <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0148727#pone.0148727.s004" target="_blank">S1</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0148727#pone.0148727.s006" target="_blank">S3</a> Movies). Mitochondrial depolarization began at 6 h 05 minutes and ended at 6 h 25 minutes, when nuclear volume began to decrease. (B) Cell shape, 3D structure of the TMRE signal, chromatin and nucleus. For each time point, one DIC image (left), one optical section for the red and green signals, a 3D view (surface rendering) of the TMRE signal and a 3D view (surface rendering) of both TMRE signal (red) and H2B-GFP (green) are shown. On DIC image, yellow dotted line indicates the limit of the cell. On 3D view of both TMRE signal (red) and H2B-GFP (green), the relative intensity of the red signal and the volume of the nucleus are indicated by the red and green labels, respectively. Typical chromatin and nucleus structures defined the main stages of apoptosis: stage 1 (ST 1) to stage 5 (ST 5). At the far right of the bottom row, one cell unaffected by AMD after 7 h and 15 minutes is defined as a stage 0 cell (ST 0). In this cell, TMRE staining appears as a 3D network of filaments and the angular nucleus contains a segregated nucleolus. The scale bar represents 10 μm.</p

“Elemental descriptors” gathering concentration of all the elements/ions considered, for each compartment (condensed chromatin, nucleoplasm, cytosol and mitochondria) in control cells, in cells during each stage of apoptosis and during stage 0.

<p>In the histograms, concentration of nitrogen was divided by 10 (N/10), whereas the concentration of sodium and chloride was multiplied by 3 (Na x 3 and Cl x 3).</p

Epigallocatechin-3-gallate (EGCG) inhibits the migratory behavior of tumor bronchial epithelial cells-3

Ch color on the figure corresponds to different cells. A longer distance of migration was observed for control BZR cells compared with BZR cells treated with EGCG. A significantly lower (p < 0.05) migration speed along the xy direction was observed for BZR cells in presence of EGCG at 5 μg/ml. The presence of EGCG at 7.5 μg/ml in the lower compartment of the cell culture chamber significantly decreased (p < 0.01) BZR cell migration speed along the xy, z and xyz directions, compared with BZR cell migration speed in absence of EGCG (C).<p><b>Copyright information:</b></p><p>Taken from "Epigallocatechin-3-gallate (EGCG) inhibits the migratory behavior of tumor bronchial epithelial cells"</p><p>http://respiratory-research.com/content/9/1/33</p><p>Respiratory Research 2008;9(1):33-33.</p><p>Published online 21 Apr 2008</p><p>PMCID:PMC2362119.</p><p></p