Activation of p34cdc2 protein kinase by microinjection of human cdc25C into mammalian cells. Requirement for prior phosphorylation of cdc25C by p34cdc2 on sites phosphorylated at mitosis.

International audienceHuman cdc25C protein, a specific tyrosine phosphatase that activates the p34cdc2 protein kinase at mitosis, is itself a phosphoprotein that shows increased phosphorylation during the G2-M transition. In vitro, cdc25C protein is substantially phosphorylated by purified p34cdc2-cyclin B protein kinase. Of seven putative phosphorylation sites for p34cdc2 protein kinase present in human cdc25C, five are phosphorylated by p34cdc2 protein kinase in vitro, as assessed by tryptic phosphopeptide mapping and peptide sequencing. These same sites are also phosphorylated in vivo during the G2-M transition in normal mammalian fibroblasts and have been precisely mapped. The cdc25C phosphorylated in vitro by p34cdc2 protein kinase exhibits a 2-3-fold higher activity than the nonphosphorylated cdc25C, as assayed by activation of inactive cdc2 prokinase. Microinjection of purified cdc25C proteins into living fibroblasts reveals that only the phosphorylated form of cdc25 is highly effective in activating G2 cells into premature prophase in a manner similar to microinjection of purified active p34cdc2 protein kinase. Together these data show that multisite phosphorylation of cdc25C by p34cdc2-cyclin B protein kinase occurs at the G2-M transition and is sufficient to induce the autoamplification of cdc2/M-phase promoting factor necessary to drive somatic mammalian cells into mitosis

Semi-automated repetitive sequence-based PCR amplification for species of the Scedosporium apiospermum complex

International audiencePurpose: The Scedosporium apiospermum species complex usually ranks second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF), but little is known about the molecular epidemiology of the airway colonization.Methods: Polymerase chain reaction (PCR) amplification of repetitive sequences (rep-PCR) was applied to the retrospective analysis of a panel of isolates already studied by random amplification of polymorphic DNA (RAPD) and comprising 63 isolates recovered from sputa from 9 CF patients. Results were compared to those obtained previously by RAPD, and herein by beta-tubulin (TUB) gene sequencing and Multilocus Sequence Typing (MLST).Results: Within the panel of isolates studied, S. apiospermum sensu stricto and Sce-dosporium boydii, as expected, were the predominant species with 21 and 36 isolates, respectively. Four isolates from one patient were identified as Scedosporium auranti-acum, whereas two isolates belonged to the Pseudallescheria ellipsoidea subgroup of S. boydii. rep-PCR analysis of these isolates clearly differentiated the three species and P. ellipsoidea isolates, whatever the rep-PCR kit used, and also permitted strain differentiation. When using the mold primer kit, results from rep-PCR were in close agreement with those obtained by MLST. For both S. apiospermum and S. boydii, 8 genotypes were differentiated by rep-PCR and MLST compared to 10 by RAPD. All S. aurantiacum isolates shared the same RAPD genotype and exhibited the same rep-PCR profile and sequence type.Conclusions: These results illustrate the efficacy of rep-PCR for both species identification within the S. apiospermum complex and genotyping for the two major species of this comple

Differential Expression of Salivary Proteins between Susceptible and Insecticide-Resistant Mosquitoes of Culex quinquefasciatus

Background: The Culex quinquefasciatus mosquito, a major pest and vector of filariasis and arboviruses in the tropics, has developed multiple resistance mechanisms to the main insecticide classes currently available in public health. Among them, the insensitive acetylcholinesterase (ace-1(R) allele) is widespread worldwide and confers cross-resistance to organophosphates and carbamates. Fortunately, in an insecticide-free environment, this mutation is associated with a severe genetic cost that can affect various life history traits. Salivary proteins are directly involved in human-vector contact during biting and therefore play a key role in pathogen transmission. Methods and Results: An original proteomic approach combining 2D-electrophoresis and mass spectrometry was adopted to compare the salivary expression profiles of two strains of C. quinquefasciatus with the same genetic background but carrying either the ace-1(R) resistance allele or not (wild type). Four salivary proteins were differentially expressed (> 2 fold, P < 0.05) in susceptible (SLAB) and resistant (SR) mosquito strains. Protein identification indicated that the D7 long form, a major salivary protein involved in blood feeding success, presented lower expression in the resistant strain than the susceptible strain. In contrast, three other proteins, including metabolic enzymes (endoplasmin, triosephosphate isomerase) were significantly over-expressed in the salivary gland of ace-1(R) resistant mosquitoes. A catalogue of 67 salivary proteins of C. quinquefasciatus sialotranscriptome was also identified and described. Conclusion: The "resistance"-dependent expression of salivary proteins in mosquitoes may have considerable impact on biting behaviour and hence on the capacity to transmit parasites/viruses to humans. The behaviour of susceptible and insecticide-resistant mosquitoes in the presence of vertebrate hosts and its impact on pathogen transmission urgently requires further investigation

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Etude de faisabilité d'une formulation transdermique de métopimazine à usage pédiatrique

La fréquence des gastro-entérites aiguës est importante en pédiatrie. La difficulté que représente une prise médicamenteuse sous la forme habituelle (voie orale ou rectale) au moment des troubles digestifs et la facilité d'accès de la voie transdermique font envisager la réalisation d'un dispositif transdermique à base d'un anti-vomitif. La métopimazine est une molécule intéressante pour la réalisation de ce dispositif mais il est indispensable d'utiliser un promoteur d'absorption pour favoriser son passage à travers la peau. Les produits choisis sont le propylène glycol, le myristate d'isopropyle et l'acide caprique.ROUEN-BU Médecine-Pharmacie (765402102) / SudocSudocFranceF

Temporal dominance of sensations and sensory profiling: a comparative study

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Strontium Vanadate Deposited by ALD: Toward a New Synthesis Approach

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Strontium Vanadate Deposited by ALD: Toward a New Synthesis Approach

International audienceTransparent conductive oxides (TCOs) have a wide range of potential applications in fields such as photovoltaics, touch screens, and smart windows. The challenging task when developing conventional TCOs like tin-doped indium oxide (ITO) by the traditional method is to make them more conducting by increasing the concentration of charge carriers without compromising the optical transparency [1]. Another novel approach involves increasing the plasma energy to widen the transparency window by increasing the charge carriers' effective mass. This approach has led to growing interest in perovskite transition metal oxides such as CaVO3 and SrVO3 due to their strong electronic correlation, which results in plasma energy shifting to higher energies than classical TCOs [2,3]. However, obtaining a crystallized film in the perovskite SrVO3 phase for optimal electrical conduction and optical transparency is challenging, particularly at low growth temperatures and when deposited on amorphous substrates like glasses [2, 4].As a result, atomic layer deposition (ALD) has emerged as a promising technique for depositing conformal layers on large surfaces with high aspect ratios and low thermal budgets. In this study, we investigated the deposition of strontium vanadium oxide films by ALD using vanadium tri-isopropoxide (VTIP) as the vanadium precursor, strontium bis(isopropylcyclopentadienyl) (Sr(iPr3Cp)2) from Air Liquide company as the strontium precursor, and water as a reagent, respectively. We deposited SrVO3 films on (100) Silicon and glass substrates at 240°C and annealed them under forming gas (95% Ar, 5% H2) at 500°C for one hour. We paid particular attention to the deposition of an anatase TiO2 buffer layer to promote the crystallization of SVO.The unannealed films were found to be completely amorphous whatever the substrate, and regardless of the presence or not of the TiO2 crystallized buffer. The EDX, STEM-HAADF and SIMS analyses revealed that the buffer is a key element to avoid the Si diffusion in SVO layer, before, and even more upon annealing. The annealed samples with a buffer layer deposited on both substrates were crystallized into various SrxVyOz phases according to the Sr amount, controlled by the Sr cycles ratio (RSR) (figure). The XRD data allowed the identification of the Sr3VO8 and Sr2VO4 phases, where the last one favors the higher Sr amount. The influence of the substrate is significant and discussed. Furthermore, we characterized the films' optical properties using spectroscopic ellipsometry in the UV-visible range. We analyzed the refractive index and extinction coefficient behavior according to the Sr amount and evaluated the effect of annealing. We estimated the band gap energy using Tauc-Lorentz and Tauc plot models and discussed it in relation to the Sr amount and the obtained phases.Our study provides not only valuable insights into the deposition and characterization of SrVO3 thin films for potential TCO applications, but also on Sr3VO8 and Sr2VO4 phases, which may be of interest for their transparent oxide optical properties. New ALD growth strategies to improve the SrVO3 phases will be presented as a perspective of this study and as an example of using different V precursor or reactive atmospheres during ALD process

Influence of post annealing treatments on the luminescence of rare earth ions in ZnO:Tb,Eu/Si heterojunction

International audience(Tb, Eu)–co-doped ZnO films with about 3 at.% total doping rate were grown by magnetron sputtering on Si substrate. Post annealing treatments were performed at 973–1373 K in continuous nitrogen flow to investigate the transformation of microstructural and optical characteristics by means of X-ray diffraction, transmission electron microscopy, photoluminescence and electroluminescence. For annealing temperatures lower than 1073 K, segregation of Eu and Tb was observed mainly at the film/substrate junction. For temperatures higher than 1173 K, additional phases appeared, namely, Zn2SiO4 and rare earth silicates. For the highest temperature investigated (1373 K), only silica and rare earth silicates remained in the film due to Zn evaporation. PL measurements indicated a very intense Eu emission associated with the presence of rare earth silicate inclusions. Energy transfer from Tb towards Eu was evidenced in this secondary phase. At last, based on these preliminary works, a (Tb, Eu)–co-doped ZnO/Si electroluminescent structure was produced and showed very promising results paving the way for very thin ZnO based light emitting diodes