Le Peuple : organe quotidien du syndicalisme

29 juillet 19341934/07/29 (A14,N4940)-1934/07/29

GSK1016790A-induced TRPV4-currents and inhibition by HC067047 in the melanoma lines, MKTBR and SK-MEL-28, and the human non-cancer keratinocyte line, HaCaT.

<p>Data points are means ± SEM (cells, n = 4–6 each). Panel on right: Quantitative RT-PCR analysis of TRPV4 and KCa3.1 gene expression in HaCaT as percentage of GAPDH expression (replicates, n = 3). Data points are means ± SEM.</p

Impact of GSK1016790A on cell proliferation/survival.

<p>A) Upper panel on left: Concentration-dependent reduction of cell proliferation/survival of A375 as measured by Janus Green-Assay. Upper panel on right: Note that half-maximal inhibition was achieved at ca. 1 nM GSK1016790A for all time intervals, except day-1. Lower panel on left: HC067047 antagonized the response to GSK1016790A. Lower panel on right: The negative gating-modulator of KCa3.1, the 13b derivate, RA-2 (10 μM) reduced cell proliferation/survival and potentiated the response to GSK1016790A. The positive-gating modulator of KCa3.1, SKA-121, had no effects. Data points are means ± SEM (n = 6–36 from n = 2–6 independent experiments). B) GSK1016790A impaired proliferation/survival of HaCaT cells. HC067047 partially antagonized the response. The negative and positive KCa3.1-gating modulators, RA-2 and SKA-121, respectively, did not modulate the response. Data points are means ± SEM (n = 18; number of independent experiments, n = 3). *P<0.05 vs. DMSO, #P<0.05 vs. GSK1016790A; Student’s T test.</p

Characterization of TRPV4 channels in A375 melanoma cells.

<p>A) Upper panel: Exemplary whole-cell recordings showing activation of TRPV4 channels by GSK1016790A (200 nM) and inhibition of currents by HC067047 (1 μM). The arrow indicates a positive reversal potential of GSK1016790A-activated currents. Baseline currents were not considerable inhibited by HC067047. Lower panel: Co-activation of K_Ca-currents. The right arrow indicates a negative reversal potential (E_rev) of ca. -35 mV of the mixed TRPV4 and K_Ca current and the left arrow indicates an E_rev of ca. -75 mV of the isolated K_Ca-current after inhibition of TRPV4 currents by HC067047. The K_Ca-current was fully blocked by the negative-gating modulator of KCa3.1 channels, 13b (1 μM). B) Upper panel: Mean normalized currents at clamp potentials of -80 and +80 mV before and after addition GSK1016790A (n = 8, experiments) and after addition of HC067047 (n = 8). Lower panel: Mean mixed TRPV4/KCa3.1 currents at a clamp potential of 0 mV after addition of GSK1016790A (n = 5) and inhibition of TRPV4 currents by HC067047 (n = 4) and of KCa3.1 currents by 13b (n = 5). C) Quantitative RT-PCR analysis of TRPV4 and KCa3.1 gene expression as percentage of GAPDH expression (replicates, n = 3). Data points are means ± SEM.</p

FACS analysis of apoptosis.

<p>A) Representative flow cytometry dot plots with double Annexin V-FITC/PI staining for control cells (DMSO 0,2%), cells exposed to GSK1016790A (10 nM), and cells exposed to GSK1016790A and HC067047 (1 μM) at 1 h, 24 h, and 72 h. B) Summary data. C) Induction of apoptosis in HaCaT cells and protective effects of HC067047. D) Summary data. *P<0.05 vs. Control, #P<0.05 vs. GSK1016790A, ANOVA, n = 3). Data are means ± SEM (number of independent experiments, n = 3).</p

Alterations of cell morphology, cell detachment and cell death induced by GSK1016790A.

<p>A) Upper two panels: Exemplary light microscopic images illustrating time course of cell retraction, membrane blebbing (indicated by arrows), and cell detachment during the first hour of exposure to GSK1016790A (1 μM). HC067047 (1 μM) prevented visibly GSK1016790A-induced changes. HC067047 or vehicle (DMSO) had no visible effect. Lower panel: Giemsa-stained A375 cells after 1 h exposure to GSK1016790A, in combination with HC067047, or DMSO. Note the densification of nuclei (dark-grey dots indicated by arrows) in GSK1016790A-treated cells. B) Counts of non-viable, “death” cells in supernatant. Data points are means ± SEM (number of independent experiments, n = 3). *P<0.05 vs. DMSO, #P <0.05 vs. GSK1016790A; Student’s T test.</p

Association between administration of IL-6 antagonists and mortality among patients hospitalized for COVID-19 : a meta-analysis

IMPORTANCE Clinical trials assessing the efficacy of IL-6 antagonists in patients hospitalized for COVID-19 have variously reported benefit, no effect, and harm. OBJECTIVE To estimate the association between administration of IL-6 antagonists compared with usual care or placebo and 28-day all-cause mortality and other outcomes. DATA SOURCES Trials were identified through systematic searches of electronic databases between October 2020 and January 2021. Searches were not restricted by trial status or language. Additional trials were identified through contact with experts. STUDY SELECTION Eligible trials randomly assigned patients hospitalized for COVID-19 to a group in whom IL-6 antagonists were administered and to a group in whom neither IL-6 antagonists nor any other immunomodulators except corticosteroids were administered. Among 72 potentially eligible trials, 27 (37.5%) met study selection criteria. DATA EXTRACTION AND SYNTHESIS In this prospectivemeta-analysis, risk of biaswas assessed using the Cochrane Risk of Bias Assessment Tool. Inconsistency among trial results was assessed using the I-2 statistic. The primary analysis was an inverse variance-weighted fixed-effects meta-analysis of odds ratios (ORs) for 28-day all-cause mortality. MAIN OUTCOMES AND MEASURES The primary outcome measurewas all-cause mortality at 28 days after randomization. There were 9 secondary outcomes including progression to invasive mechanical ventilation or death and risk of secondary infection by 28 days. RESULTS A total of 10 930 patients (median age, 61 years [range of medians, 52-68 years]; 3560 [33%] were women) participating in 27 trials were included. By 28 days, there were 1407 deaths among 6449 patients randomized to IL-6 antagonists and 1158 deaths among 4481 patients randomized to usual care or placebo (summary OR, 0.86 [95% CI, 0.79-0.95]; P =.003 based on a fixed-effects meta-analysis). This corresponds to an absolute mortality risk of 22% for IL-6 antagonists compared with an assumed mortality risk of 25% for usual care or placebo. The corresponding summary ORs were 0.83 (95% CI, 0.74-0.92; P <.001) for tocilizumab and 1.08 (95% CI, 0.86-1.36; P =.52) for sarilumab. The summary ORs for the association with mortality compared with usual care or placebo in those receiving corticosteroids were 0.77 (95% CI, 0.68-0.87) for tocilizumab and 0.92 (95% CI, 0.61-1.38) for sarilumab. The ORs for the association with progression to invasive mechanical ventilation or death, compared with usual care or placebo, were 0.77 (95% CI, 0.70-0.85) for all IL-6 antagonists, 0.74 (95% CI, 0.66-0.82) for tocilizumab, and 1.00 (95% CI, 0.74-1.34) for sarilumab. Secondary infections by 28 days occurred in 21.9% of patients treated with IL-6 antagonists vs 17.6% of patients treated with usual care or placebo (OR accounting for trial sample sizes, 0.99; 95% CI, 0.85-1.16). CONCLUSIONS AND RELEVANCE In this prospectivemeta-analysis of clinical trials of patients hospitalized for COVID-19, administration of IL-6 antagonists, compared with usual care or placebo, was associated with lower 28-day all-cause mortality