27 research outputs found
GRI: focusing on the evolving violent universe
No full textThe gamma-ray imager (GRI) is a novel mission concept that will provide an unprecedented sensitivity leap in the soft gamma-ray domain by using for the first time a focusing lens built of Laue diffracting crystals. The lens will cover an energy band from 200-1,300 keV with an effective area reaching 600 cm(2). It will be complemented by a single reflection multilayer coated mirror, extending the GRI energy band into the hard X-ray regime, down to similar to 10 keV. The concentrated photons will be collected by a position sensitive pixelised CZT stack detector. We estimate continuum sensitivities of better than 10 (-aEuro parts per thousand 7) ph cm (-aEuro parts per thousand 2)s (-aEuro parts per thousand 1)keV (-aEuro parts per thousand 1) for a 100 ks exposure; the narrow line sensitivity will be better than 3 x 10 (-aEuro parts per thousand 6) ph cm (-aEuro parts per thousand 2)s (-aEuro parts per thousand 1) for the same integration time. As focusing instrument, GRI will have an angular resolution of better than 30 arcsec within a field of view of roughly 5 arcmin-an unprecedented achievement in the gamma-ray domain. Owing to the large focal length of 100 m of the lens and the mirror, the optics and detector will be placed on two separate spacecrafts flying in formation in a high elliptical orbit. R&D work to enable the lens focusing technology and to develop the required focal plane detector is currently underway, financed by ASI, CNES, ESA, and the Spanish Ministery of Education and Science. The GRI mission has been proposed as class M mission for ESAs Cosmic Vision 2015-2025 program. GRI will allow studies of particle acceleration processes and explosion physics in unprecedented detail, providing essential clues on the innermost nature of the most violent and most energetic processes in the universe
Fact Sheets. Central Africa, West Africa, Antarctica and Sub-Antarctic Islands, Continental South-East Asia, Mediterranean Basin, Caribbean and Guiana Shield, Northern America - Canada, European Continent, Indian Ocean, Oceania
No full textFiches techniques. Afrique Centrale, Afrique Occidentale, Antarctique et Iles Subantarctiques, Asie du Sud-Est Continentale, Bassin Méditerranéen, Caraïbes et Plateau des Guyanes, Amérique du Nord Septentrionale, Canada, Europe Continentale, Océan Indien, Océanie
No full textKetoconazole inhibits 1,25(OH)<sub>2</sub>D<sub>3</sub> production and up-regulation of the VDR.
No full text<p>(A) 1,25(OH)<sub>2</sub>D<sub>3</sub> in the supernatants of T cells activated in the presence of 100 nM of 25(OH)D<sub>3</sub> and the indicated concentrations of ketoconazole. Mean + SEM (<i>n</i> = 3; * p<0.05). (B) Representative Western blot of VDR and CD3ζ (loading control) expression in T cells activated in the presence of the indicated concentrations of ketoconazole, 25(OH)D<sub>3</sub> (100 nM) and 1,25(OH)<sub>2</sub>D<sub>3</sub> (10 nM). (C) Relative VDR protein expression in T cells activated in the presence of the indicated concentrations of ketoconazole, 25(OH)D<sub>3</sub> (100 nM) and 1,25(OH)<sub>2</sub>D<sub>3</sub> (10 nM). The density of the VDR bands obtained by Western blot analysis were normalized to the density of the VDR bands of T cells stimulated in the absence of ketoconazole, 25(OH)D<sub>3</sub> and 1,25(OH)<sub>2</sub>D<sub>3</sub>. Mean + SEM (<i>n</i> = 3; * p<0.01).</p
1,25(OH)<sub>2</sub>D<sub>3</sub> increases the half-life of the VDR.
No full text<p>(A) Representative Western blot of VDR and CD3ζ (loading control) in whole cell lysates from T cells activated in the absence or presence of 25(OH)D<sub>3</sub> (100 nM) and then treated with cycloheximide (10 µg/ml) for the time indicated. The half-lives (t½) for the VDR in the absence or presence of 25(OH)D<sub>3</sub> are given below the blot. (B) Relative VDR protein expression obtained from Western blot analysis of whole cell lysates from T cells activated in the absence (W) or presence (W +25(OH)D<sub>3</sub>) of 25(OH)D<sub>3</sub> (100 nM) and then treated with cycloheximide (10 µg/ml) for the time indicated. The density of the VDR bands were normalized to the density of the VDR bands at time zero of T cells stimulated in the presence of 25(OH)D<sub>3</sub>. Shown are the mean relative densities from 3 independent experiments and the curves obtained by regression analysis for W (<i>D(t) = 0.37e<sup>−0.41t</sup></i>, R<sup>2</sup> = 0.88) and W +25(OH)D<sub>3</sub> (<i>D(t) = 0.89e<sup>−0.24t</sup></i>, R<sup>2</sup> = 0.90). (C) Representative Western blot of VDR, GAPDH and CD3ζ (loading controls) expression in the cytoplasmic (C) and nuclear (N) fractions of T cells activated in the absence or presence of 25(OH)D<sub>3</sub> (100 nM) and T cells activated in the absence of 25(OH)D<sub>3</sub> and then treated for 4 h with 1,25(OH)<sub>2</sub>D<sub>3</sub> (10 nM). (D) Distribution of the VDR in the cytoplasmic (C) and nuclear (N) fractions of T cells treated as described in (C), mean + SEM (n≥4; * p<0.01). (E) Representative Western blot of VDR and CD3ζ (loading control) expression in the cytoplasmic fraction of T cells treated as described in (A). (F) Relative VDR protein expression obtained from Western blot analysis of the cytoplasmic fraction from T cells activated in the absence (C) or presence (C +25(OH)D<sub>3</sub>) of 25(OH)D<sub>3</sub> (100 nM) and then treated with cycloheximide (10 µg/ml) for the time indicated. The density of the VDR bands were normalized to the density of the VDR bands at time zero of T cells stimulated in the presence of 25(OH)D<sub>3</sub>. Shown are the mean relative densities from 3 independent experiments and the curves obtained by regression analysis for C (<i>D(t) = 2.11e<sup>−0.44t</sup></i>, R<sup>2</sup> = 0.94) and C +25(OH)D<sub>3</sub> (<i>D(t) = 0.76e<sup>−0.26t</sup></i>, R<sup>2</sup> = 0.70). (G) Representative Western blot of VDR expression in the nuclear fraction of T cells treated as described in (A). (H) Relative VDR protein expression obtained from Western blot analysis of the nuclear fraction from T cells activated in the absence (N) or presence (N +25(OH)D<sub>3</sub>) of 25(OH)D<sub>3</sub> (100 nM) and then treated with cycloheximide (10 µg/ml) for the time indicated. The density of the VDR bands were normalized to the density of the VDR bands at time zero of T cells stimulated in the presence of 25(OH)D<sub>3</sub>. Shown are the mean relative densities from 3 independent experiments and the curves obtained by regression analysis for N (<i>D(t) = 0.68e<sup>−0.53t</sup></i>, R<sup>2</sup> = 0.99) and N +25(OH)D<sub>3</sub> (<i>D(t) = 0.86e<sup>−0.23t</sup></i>, R<sup>2</sup> = 0.90).</p
Leptomycin B neither inhibits nuclear export nor degradation of the VDR.
No full text<p>(A) Representative Western blot of VDR, p53 and CD3ζ (loading control) in whole cell lysates of T cells activated for 3 d in the absence of 25(OH)D<sub>3</sub> and then treated with the indicated concentrations (ng/ml) of leptomycin B (LMB) for 4 h. (B) Relative VDR and p53 protein expression obtained from Western blot analysis of whole cell lysates from T cells treated as described in A. The density of the VDR and p53 bands were normalized to the density of the VDR and p53 bands of T cells not treated with LMB, respectively. Results are presented as mean + SEM (<i>n</i> = 3; * p<0.05). (C) Representative Western blot of VDR, p53 and CD3ζ (loading control) in cytoplasmic (C) and nuclear (N) fractions of T cells treated as described in A.</p
The VDR is spontaneously degraded by the proteasomes.
No full text<p>(A, B) Representative Western blot of VDR and CD3ζ (loading control) in (A) whole cell lysates and (B) cytoplasmic (C) and nuclear (N) fractions of T cells activated for 3 d in the absence of 25(OH)D<sub>3</sub> and then pre-treated with the indicated concentrations of lactacystin (µM) for 1 h before treatment with cycloheximide (10 µg/ml) as indicated for one additional h. (C) Relative VDR protein expression obtained from Western blot analysis of whole cell lysates (W), cytoplasmic (C) and nuclear (N) fractions from T cells treated as described in A and B. The density of the VDR bands were normalized to the density of the VDR bands of T cells not treated with lactacystin and cycloheximide. Results are presented as mean + SEM (<i>n</i> = 3).</p
1,25(OH)<sub>2</sub>D<sub>3</sub> stabilizes the VDR by protecting it from proteasomal degradation.
No full text<p>(A) Representative Western blot of VDR and CD3ζ (loading control) expression in whole cell lysates of T cells activated for 3 d in the absence or presence of 25(OH)D<sub>3</sub> (100 nM) and then treated with lactacystin (10 µM) for the time indicated. The coefficients of inclination (coi) obtained from the curves in B are given below the blots. (B) Relative VDR protein expression obtained from Western blot analysis of whole cell lysates (W) of T cells activated for 3 d in the absence or presence (+ 25(OH)D<sub>3</sub>) of 25(OH)D<sub>3</sub> (100 nM). The density of the VDR bands were normalized to the density of the VDR bands at time zero of T cells activated in the absence or presence of 25(OH)D<sub>3</sub>, respectively. Shown are the mean relative densities from 3 independent experiments and the curves obtained by linear regression analysis of the mean values. (C) Representative Western blot of VDR, p53 and CD3ζ (loading control) in whole cell lysates of T cells activated for 3 d in the absence of 25(OH)D<sub>3</sub> and then treated with the indicated concentrations of 1,25(OH)<sub>2</sub>D<sub>3</sub> for 4 h. (D) Relative VDR and p53 protein expression obtained from Western blot analysis of whole cell lysates from T cells treated as described in C. The density of the VDR and p53 bands were normalized to the density of the VDR and p53 bands of T cells not treated with 1,25(OH)<sub>2</sub>D<sub>3</sub>, respectively. Results are presented as mean + SEM (<i>n</i> = 3; * p<0.05). (E) Relative CYP24A1 mRNA expression in T cells activated for 3 d in the absence of 25(OH)D<sub>3</sub> and then treated with increasing concentrations of 1,25(OH)<sub>2</sub>D<sub>3</sub> for 12 hours in the absence or presence of 10 µM lactacystin. The CYP24A1 mRNA levels were normalized to CYP24A1 mRNA levels of T cells not treated with1,25(OH)2D3. Results are presented as mean + SEM (<i>n</i> = 5; * p<0.05).</p
Activated human CD4<sup>+</sup> T cells produce 1,25(OH)<sub>2</sub>D<sub>3</sub> and up-regulates VDR expression in the presence of 25(OH)D<sub>3</sub>.
No full text<p>(A) 1,25(OH)<sub>2</sub>D<sub>3</sub> in the supernatants of activated and unstimulated T cells and in cell free cultures incubated with the indicated concentrations of 25(OH)D<sub>3</sub>. Mean ± SEM (<i>n</i> = 5). (B) Representative Western blot of VDR and CD3ζ (loading control) expression in naïve and activated T cells incubated in the presence of the indicated concentrations (nM) of 25(OH)D<sub>3</sub>. (C) Relative VDR protein expression as determined by the density of the VDR bands from Western blots of naïve and activated T cells incubated in the presence of the indicated concentrations (nM) of 25(OH)D<sub>3</sub>. The density of the VDR bands were normalized to the density of the VDR bands of T cells activated in the absence of 25(OH)D<sub>3</sub>. Mean + SEM (<i>n</i> = 7; * p<0.05). (D) Relative VDR mRNA expression in naïve and activated T cells incubated in the presence of the indicated concentrations (nM) of 25(OH)D<sub>3</sub>. The VDR mRNA levels were normalized to VDR mRNA levels of T cells activated in the absence of 25(OH)D<sub>3</sub>. Mean + SEM (<i>n</i> = 4; * p<0.001). (E) Relative CYP24A1 mRNA expression in naïve and activated T cells incubated in the presence of the indicated concentrations (nM) of 25(OH)D<sub>3</sub>. The CYP24A1 mRNA levels were normalized to CYP24A1 mRNA levels of T cells activated in the absence of 25(OH)D<sub>3</sub>. Mean + SEM (<i>n</i> = 3; * p<0.05). (F) Representative Western blot of VDR and CD3ζ (loading control) expression in T cells activated for 3 days in the presence of polarizing cytokines and anti-cytokine antibodies as indicated. (G) Relative VDR protein expression as determined by the density of the VDR bands from Western blots of T cells treated as described in F. The density of the VDR bands were normalized to the density of the VDR bands of T cells activated in the absence of polarizing cytokines and anti-cytokine antibodies (Th0). Mean + SEM (<i>n</i> = 2).</p
Effect of Vero E6 cell number and morphology on the relationship between SARS-CoV-2 nucleocapsid protein measured by ELISA and SARS-CoV-2 virus inoculum.
No full textTriplicate serial dilutions (0.5 log10-fold) of a Danish SARS-CoV-2 clinical isolate (early pandemic strain (lineage B.1)) was added to increasing numbers of Vero E6 cells in a monolayer or in suspension. The cell numbers indicated for the monolayer are as seeded the day prior to the infection. On the day of infection, the seeded cell numbers– 6000, 8000, 10000, 12000, 14000, and 16000 –increased to 12000, 14000, 16000, 18000, 20000, and 22000, respectively. The latter cell numbers were used for the infection of suspended cells to ensure a similar multiplicity of infection for the monolayers. (A) SARS-CoV-2 virus titration curve for different cell numbers infected in a monolayer and suspension. Symbols indicate the mean and error bars the standard deviation. (B) The overall SARS-CoV-2 nucleocapsid protein signal measured for the virus dilution series, expressed as area under the curve for the Log10 decimal virus dilution and ELISA OD value as a measure of the magnitude of variance associated with changes in cell number (shown in A). Error bars represent the 95% confidence interval. (C) The percentage coefficient of variation (CV) for SARS-CoV-2 infected and mock infected cells as well as the background anti-SARS-CoV-2 nucleocapsid protein level measured for mock infected cells. For all experiments, ELISA primary antibody: rabbit mAb 40143-R019.</p
