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

Managing the challenge of drug-induced liver injury: a roadmap for the development and deployment of preclinical predictive models

Drug-induced liver injury (DILI) is a patient-specific, temporal, multifactorial pathophysiological process that cannot yet be recapitulated in a single in vitro model. Current preclinical testing regimes for the detection of human DILI thus remain inadequate. A systematic and concerted research effort is required to address the deficiencies in current models and to present a defined approach towards the development of new or adapted model systems for DILI prediction. This Perspective defines the current status of available models and the mechanistic understanding of DILI, and proposes our vision of a roadmap for the development of predictive preclinical models of human DILI

SFRP1 reduction results in an increased sensitivity to TGF-β signaling

Background Transforming growth factor (TGF)-β plays a dual role during mammary gland development and tumorigenesis and has been shown to stimulate epithelial-mesenchymal transition (EMT) as well as cellular migration. The Wnt/β-catenin pathway is also implicated in EMT and inappropriate activation of the Wnt/β-catenin signaling pathway leads to the development of several human cancers, including breast cancer. Secreted frizzled-related protein 1 (SFRP1) antagonizes this pathway and loss of SFRP1 expression is frequently observed in breast tumors and breast cancer cell lines. We previously showed that when SFRP1 is knocked down in immortalized non-malignant mammary epithelial cells, the cells (TERT-siSFRP1) acquire characteristics associated with breast tumor initiating cells. The phenotypic and genotypic changes that occur in response to SFRP1 loss are consistent with EMT, including a substantial increase in the expression of ZEB2. Considering that ZEB2 has been shown to interact with mediators of TGF-β signaling, we sought to determine whether TGF-β signaling is altered in TERT-siSFRP1 cells. Methods Luciferase reporter assays and real-time PCR analysis were employed to measure TGF-β transcriptional targets. Western blot analysis was used to evaluate TGF-β-mediated ERK1/2 phosphorylation. Migration chamber assays were utilized to quantify cellular migration. TERT-siSFRP1 cells were transfected with Stealth RNAi™ siRNA in order to knock-down the expression of ZEB2. Results TERT-siSFRP1 cells exhibit a significant increase in both TGF-β-mediated luciferase activity as well as TGF-β transcriptional targets, including Integrin β3 and PAI-1. Phosphorylation of ERK1/2 is increased in TERT-siSFRP1 cells in response to enhanced TGF-β signaling. Furthermore, when the TGF-β pathway is blocked with a TGF-βR antagonist (LY364947), cellular migration is significantly hindered. Finally, we found that when ZEB2 is knocked-down, there is a significant reduction in the expression of exogeneous and endogenous TGF-β transcriptional targets and cellular migration is impeded. Conclusions We demonstrate that down-regulation of SFRP1 renders mammary epithelial cells more sensitive to TGF-β signaling which can be partially ameliorated by blocking the expression of ZEB2

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

Cryoglobulinémie dans l'hépatite C et relation avec la charge virale. Etude rétrospective de patients inclus dans un protocole thérapeutique et revue de la littérature

CLERMONT FD-BCIU-Santé (631132104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Appariement par transformée de Fourier-Mellin d'images visibles et proche infrarouge acquises par drone

International audienceThe combination of aerial images acquired in the visible and near infrared spectral ranges is particularly relevant for agricultural and environmental survey. In unmanned aerial vehicle (UAV) imagery, such a combination can be achieved using a set of several embedded cameras mounted close to each other, followed by an image registration step. However, due to the different nature of source images, usualregistration techniques based on feature point matching are limited when dealing with blended vegetation and bare soil patterns. Here, another approach is proposed based on i mage spatial frequency analysis. This approach, which relies on the Fourier-Mellin transform, has been adapted to homographic registration and distortion issues. It has been successfully tested on various aerial image sets, and has proved to be particularly robust and accurate, providing a registration error below 0.3 pixels in most cases

Oxydation de particules de fer dans un plasma d'arc Ar-H2 s'écoulant dans l'air (influence sur les propriétés du dépot)

Lors de l'élaboration de dépôts métalliques par plasma d'arc soufflé à l'air libre,l'oxygène pompé réagit avec les particules liquides durant leur séjours dans le jet. Dans ce travail, nous avons essayé d'évaluer l'oxydation en vol de particules ,de fer pur et son influence sur les propriétés du dépôt. L'analyse des particules collectées en vol par un montage original permet de mettre en évidence la formation exclusive de l'oxyde de fer wüstite, de formule Fe0.95O. Les calculs de modélisation montrent que l'oxydation est contrôlée au coeur du jet par les phénomèmes de convection à l'intérieur des particules liquides. La formation de nodules de wüstite au coeur des gouttelettes doit être attribuée aux différences de vitesse entre le jet de plasma et les particules. Dans le cas d'un plasma Ar-H2(50:10 N1.min-1) fonctionnant avec une puissance effective de 18 kW, la phase Fe0.95O représente 13% en masse des particules collectées à 100 mm de la sortie de tuyère. Pour préciser le comportement des particules liquides lors de leur étalement sur le substrat , nous avons effectué des mesures de mouillabilité par la méthode de la goutte posée. Nos résultats montrent que l'oxydation en vol des particules de fer se traduit par une forte diminution de l'angle de contact lors de la mise en goutte sur des substrats céramiques et permet un meilleur recouvrement des lamelles. Le rôle des paramètres de projection tels que l'intensité de courant, le débit d'hydrogène plasmagème et le diamètre de la tuyère a également été étudié. L'analyse de dépôt de fer pur révèle la présence en quantité importante d'oxydes Fe3O4 et Fe2O3. Ces oxydes, formés lors des passes successives, favorisent la porosité et diminuent les qualités thermomécaniques des revêtements. Nous avons donc proposé un nouveau dispositif de projection visant à minimiser cette oxydation, sans influencer notablement sur le coût du procédé. Dans ces conditions la valeur de la force d'arrachement passe de 51 à 60 MPa, soit une amélioration de 17%. Ce travail souligne l'importance des réactions chimiques qui interviennent dans le procédé de projection par plasma d'arc soufflé dans l'air. Ces réactions chimiques sont toujours complexes mais peuvent, dans une certaine mesure, être contrôlées de façon assez fine en agissant sur les paramètres de projection.LIMOGES-BU Sciences (870852109) / SudocSudocFranceF