Nanoscale precipitation coating: the deposition of inorganic films through step-by-step spray-assembly.

Thin films and surface coatings play an important role in basic and applied research. Here we report on a new, versatile, and simple method ("precipitation coating") for the preparation of inorganic films, based on the alternate spraying of complementary inorganic salt solutions against a receiving surface on which the inorganic deposit forms. The method applies whenever the solubility of the deposited material is smaller than that of the salts in the solutions of the reactants. The film thickness is controlled from nanometers to hundreds of micrometers simply by varying the number of spraying steps; 200 spray cycles, corresponding to less than 15 min deposition time, yield films with thicknesses exceeding one micrometer and reaching tens of micrometers in some cases. The new solution-based process is also compatible with conventional layer-by-layer assembly and permits the fabrication of multimaterial sandwich-like coatings.journal articleresearch support, non-u.s. gov't2010 Aug 24importe

O2 Level Controls Hematopoietic Circulating Progenitor Cells Differentiation into Endothelial or Smooth Muscle Cells

BACKGROUND:Recent studies showed that progenitor cells could differentiate into mature vascular cells. The main physiological factors implicated in cell differentiation are specific growth factors. We hypothesized that simply by varying the oxygen content, progenitor cells can be differentiated either in mature endothelial cells (ECs) or contractile smooth muscle cells (SMCs) while keeping exactly the same culture medium. METHODOLOGY/PRINCIPAL FINDINGS:Mononuclear cells were isolated by density gradient were cultivated under hypoxic (5% O2) or normoxic (21% O2) environment. Differentiated cells characterization was performed by confocal microscopy examination and flow cytometry analyses. The phenotype stability over a longer time period was also performed. The morphological examination of the confluent obtained cells after several weeks (between 2 and 4 weeks) showed two distinct morphologies: cobblestone shape in normoxia and a spindle like shape in hypoxia. The cell characterization showed that cobblestone cells were positive to ECs markers while spindle like shape cells were positive to contractile SMCs markers. Moreover, after several further amplification (until 3(rd) passage) in hypoxic or normoxic conditions of the previously differentiated SMC, immunofluorescence studies showed that more than 80% cells continued to express SMCs markers whatever the cell environmental culture conditions with a higher contractile markers expression compared to control (aorta SMCs) signature of phenotype stability. CONCLUSION/SIGNIFICANCE:We demonstrate in this paper that in vitro culture of peripheral blood mononuclear cells with specific angiogenic growth factors under hypoxic conditions leads to SMCs differentiation into a contractile phenotype, signature of their physiological state. Moreover after amplification, the differentiated SMC did not reverse and keep their contractile phenotype after the 3rd passage performed under hypoxic and normoxic conditions. These aspects are of the highest importance for tissue engineering strategies. These results highlight also the determinant role of the tissue environment in the differentiation process of vascular progenitor cells

Meta-analysis of SHANK Mutations in Autism Spectrum Disorders: A Gradient of Severity in Cognitive Impairments.

International audienceSHANK genes code for scaffold proteins located at the post-synaptic density of glutamatergic synapses. In neurons, SHANK2 and SHANK3 have a positive effect on the induction and maturation of dendritic spines, whereas SHANK1 induces the enlargement of spine heads. Mutations in SHANK genes have been associated with autism spectrum disorders (ASD), but their prevalence and clinical relevance remain to be determined. Here, we performed a new screen and a meta-analysis of SHANK copy-number and coding-sequence variants in ASD. Copy-number variants were analyzed in 5,657 patients and 19,163 controls, coding-sequence variants were ascertained in 760 to 2,147 patients and 492 to 1,090 controls (depending on the gene), and, individuals carrying de novo or truncating SHANK mutations underwent an extensive clinical investigation. Copy-number variants and truncating mutations in SHANK genes were present in ∼1% of patients with ASD: mutations in SHANK1 were rare (0.04%) and present in males with normal IQ and autism; mutations in SHANK2 were present in 0.17% of patients with ASD and mild intellectual disability; mutations in SHANK3 were present in 0.69% of patients with ASD and up to 2.12% of the cases with moderate to profound intellectual disability. In summary, mutations of the SHANK genes were detected in the whole spectrum of autism with a gradient of severity in cognitive impairment. Given the rare frequency of SHANK1 and SHANK2 deleterious mutations, the clinical relevance of these genes remains to be ascertained. In contrast, the frequency and the penetrance of SHANK3 mutations in individuals with ASD and intellectual disability-more than 1 in 50-warrant its consideration for mutation screening in clinical practice

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

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

Left atrial remodelling assessed by 2D and 3D echocardiography identifies paroxysmal atrial fibrillation

Aims Paroxysmal atrial fibrillation (PAF) is common, often silent, and can be difficult to detect. Echocardiographic parameters assessing left atrial (LA) remodelling correlated with atrial fibrosis in permanent AF, but less is known about earlier stages such as PAF. We aimed to evaluate whether 2D and 3D echocardiographic (2DE and 3DE) assessment of LA anatomy and function is able to identify patients with PAF.Methods and results This case control study included 102 patients without overt heart disease, 44 patients with PAF. Anatomical remodelling was assessed using indexed maximal, minimal, and preatrial contraction volumes. Reservoir, conduit, and pump functions were assessed by volume and strain methods. All parameters were assessed by 2DE and 3DE and were compared between the two groups. Receiver-operating characteristic curves were constructed for each parameter for PAF prediction. PAF patients had bigger LA volumes than non-PAF group. Using 3DE, all atrial functions were impaired in the PAF group, regardless of the parameters used (all P < 0.05), whereas using 2DE, conduit function did not reach significant difference. Areas under the curve (AUCs) for 3D parameters were higher than those for equivalent 2DE parameters. PAF was best predicted by LA minimal indexed volume assessed by 2DE or 3DE (AUC 0.82 and 0.86, respectively) and 3D-LA ejection fraction and area strain (AUC = 0.82 and 0.81, respectively).Conclusion Anatomical and functional LA remodelling assessed by 2DE and 3DE is independently and strongly associated with PAF, suggesting that these parameters can help identify PAF

Quelle type de troponine de haute sensibilité choisir pour caractériser au mieux la taille d'infarctus et l'obstruction microvasculaire?

International audienceBackground: The link between hs-Tn and infarct size has already been proved in several articles. However few is known about the kinetic of the troponin and its link to the infarct characteristics, likewise MVO. Our primary objective was to study which hs-Tn characterizes the best infarction.Methods and results: We identified 29 consecutive STEMI patients to study. The kinetics of hs-TnT (Roche) and two different TnIs (hs-TnI from Abbott, s-TnI from Siemens) were evaluated for all patients. Area under curves (AUC), first peak (FP) and second peak (SP), for hs-TnT, were compared to IS and MVO size using contrast-enhanced cardiac magnetic resonance. For IS, statistically SP of hs-TnT presented the best correlation compared to other peak values [r = 0.9 vs. 0.73 for FP hs-TnT; vs. 0.69 for hs-TnI; vs. 0.57 for s-TnI; respectively P < 0.01, P < 0.01, P < 0.01]. For MVO size, statistically SP of hs-TnT presented the best correlation compared to other peak values [r = 0.84 vs. 0.75 for FP hs-TnT; vs. 0.72 for hs-TnI; vs. 0.62 for s-TnI; respectively P = 0.01, P < 0.01, P < 0.01]. The best AUC were archived by the hs-TnT (AUC = 0.95) but there were no statistical differences when compared to other hs-Tn AUC.Conclusion: The SP of hs-TnT had the greatest level of correlation and therefore seems to be the best biological parameter to evaluate and characterize infarct size.Introduction: La relation en troponine hypersensible et taille d’infarctus a été prouvée dans de nombreux articles. Cependant, peu de relations ont été établies entre cinétique de troponine et les caractéristiques de l’infarctus, notamment l’obstruction microvasculaire. Notre objectif principal était d’étudier quelle troponine de haute sensibilité caractérisait le mieux l’infarctus du myocarde.Méthodes et résultats: 29 patients ayant subi un infarctus du myocarde aigu ont été inclus consécutivement dans cette étude. Les cinétiques de la troponine T-hs (Roche) et deux troponines I (hs-TnI de chez Abbott, s-TnI de chez Siemens) ont été évaluées pour tous les patients. Les aires sous la courbe, la valeur du premier pic (PP) et du second pic (SP), pour la troponine T-hs, étaient comparées aux valeurs de taille d’infarctus et d’obstruction microvasculaire mesurées par IRM cardiaque. Concernant la taille de la nécrose, le second pic (SP) de troponine T-hs (hs-TnT) avait la meilleure corrélation en comparaison des autres valeurs de pic (r = 0,9 vs 0,73 pour le PP de hs-TnT ; vs 0,69 pour le pic de hs-TnI ; vs 0,57 pour le pic de s-TnI ; respectivement p < 0,01, p < 0,01, p < 0,01). Concernant la taille de l’obstruction microvasculaire, le SP de hs-TnT présentait la meilleure corrélation également en comparaison des autres valeurs de pics (r = 0,84 vs 0,75 pour PP de hs-TnT ; vs 0,72 pour le pic de hs-TnI ; vs 0,62 pour le pic de s-TnI ; respectivement p = 0,01, p < 0,01, p < 0,01). La meilleure aire sous la courbe de troponine était retrouvée avec la hs-TnT (AUC = 0,95), sans différence significative cependant comparativement aux autres troponines.Conclusion: Le second pic de troponine T-hs semblait être le meilleur paramètre biologique d’évaluation des caractéristiques de l’infarctus du myocarde

Chromatin de-condensation by switching substrate elasticity

Mechanical properties of the cellular environment are known to influence cell fate. Chromatin de-condensation appears as an early event in cell reprogramming. Whereas the ratio of euchromatin versus heterochromatin can be increased chemically, we report herein for the first time that the ratio can also be increased by purely changing the mechanical properties of the microenvironment by successive 24 h-contact of the cells on a soft substrate alternated with relocation and growth for 7 days on a hard substrate. An initial contact with soft substrate caused massive SW480 cancer cell death by necrosis, whereas approximately 7% of the cells did survived exhibiting a high level of condensed chromatin (21% heterochromatin). However, four consecutive hard/soft cycles elicited a strong chromatin de-condensation (6% heterochromatin) correlating with an increase of cellular survival (approximately 90%). Furthermore, cell survival appeared to be reversible, indicative of an adaptive process rather than an irreversible gene mutation(s). This adaptation process is associated with modifications in gene expression patterns. A completely new approach for chromatin de-condensation, based only on mechanical properties of the microenvironment, without any drug mediation is presented