17 research outputs found

    CXCR4 Expression in Prostate Cancer Progenitor Cells

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    Tumor progenitor cells represent a population of drug-resistant cells that can survive conventional chemotherapy and lead to tumor relapse. However, little is known of the role of tumor progenitors in prostate cancer metastasis. The studies reported herein show that the CXCR4/CXCL12 axis, a key regulator of tumor dissemination, plays a role in the maintenance of prostate cancer stem-like cells. The CXCL4/CXCR12 pathway is activated in the CD44+/CD133+ prostate progenitor population and affects differentiation potential, cell adhesion, clonal growth and tumorigenicity. Furthermore, prostate tumor xenograft studies in mice showed that a combination of the CXCR4 receptor antagonist AMD3100, which targets prostate cancer stem-like cells, and the conventional chemotherapeutic drug Taxotere, which targets the bulk tumor, is significantly more effective in eradicating tumors as compared to monotherapy

    Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

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    RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

    Décès maternels par embolie amniotique : une étude nationale en France

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    Background: a structured definition of amniotic fluid embolism (AFE) based on 4 criteria was proposed for use in research by the SMFM and the AFE Foundation. The objective of this study was to review AFE-related maternal deaths in France (2007-2011) according to the presence or not of all 4 diagnostic criteria. Methods: maternal deaths due to AFE were identified by the National Experts Committee of the French Confidential Enquiry into Maternal Deaths (CNEMM) (n=39). The maternal mortality ratio (MMR) for AFE was calculated. We applied the structured definition to AFE-related maternal deaths identified by the CNEMM. We described the characteristics of women, pregnancies and deliveries; clinical and biological features of AFE; and specific laboratory tests by the presence or not of all 4 diagnostic criteria. Management of obstetric hemorrhage and quality of care according to the experts were described. Results: the MMR from AFE was 0,95/100,000 live births (95CI 0,67-1,3). Detailed clinical data were collected for 36 women: 21 (58%) had all 4 diagnostic criteria and 15 (42%) had at least one missing. Documented early coagulopathy was missing for 14 women. Opportunities to improve care included timely performance of indicated hysterectomy (n=13) and improved transfusion practices (n=9). In the context of maternal cardiac arrest, for 5 of 13 women, fetal extraction was performed within 5 min. Conclusions: the structured definition of AFE for research studies would exclude more than 1/3 of AFE-related maternal deaths identified by the CNEMM. Inclusion of clinical coagulopathy as diagnostic criterion for AFE would reduce this proportion to 14%.Introduction : une définition standardisée de l'embolie amniotique (EA) pour la recherche, basée sur 4 critères diagnostiques a été proposée par la SMFM et AFE Foundation. L'objectif de l'étude était de décrire les décès maternels par EA en France (2007-2011) selon la présence des 4 critères de la définition. Méthodes : 39 décès maternels par EA ont été identifiés par le Comité National d'Experts sur la Mortalité Maternelle (CNEMM). Nous avons calculé le ratio de mortalité maternelle (RMM) par EA et avons appliqué la définition aux décès maternels par EA identifiés par le CNEMM. Nous avons décrit les caractéristiques des femmes, de la grossesse, de l'accouchement, les présentations cliniques et biologiques de l’EA selon la présence des critères de la définition standardisée, la prise en charge de l'hémorragie obstétricale, ainsi que la qualité des soins selon le jugement des experts. Résultats : le RMM était de 0,95/100000 naissances vivantes, IC95%[0,67-1,3]. 36 dossiers de femmes décédées d'EA ont pu être analysés : 21 (58%) avaient les 4 critères diagnostiques et 15 (42%) avaient au moins un critère manquant. La CIVD documentée était absente dans 14 cas. Les axes d'amélioration de prise en charge étaient le délai de réalisation de l'hystérectomie d'hémostase (n=13) et l’optimisation de la stratégie transfusionnelle (n=9). En cas d'arrêt cardiaque maternel, l'extraction fœtale a été réalisée dans les 5 min dans 5 cas sur 13. Conclusions : la définition standardisée de l'EA pour la recherche a exclu plus de 1/3 des décès maternels identifiés par le CNEMM. L'ajout de la coagulopathie clinique comme critère diagnostique réduirait cette proportion à 14%

    Anesthesiology

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    Centrifugation-based autotransfusion devices only salvage red blood cells while platelets are removed. The same™ device (Smart Autotransfusion for ME; i-SEP, France) is an innovative filtration-based autotransfusion device able to salvage both red blood cells and platelets. The authors tested the hypothesis that this new device could allow a red blood cell recovery exceeding 80% with a posttreatment hematocrit exceeding 40%, and would remove more than 90% of heparin and 75% of free hemoglobin. Adults undergoing on-pump elective cardiac surgery were included in a noncomparative multicenter trial. The device was used intraoperatively to treat shed and residual cardiopulmonary bypass blood. The primary outcome was a composite of cell recovery performance, assessed in the device by red blood cell recovery and posttreatment hematocrit, and of biologic safety assessed in the device by the washout of heparin and free hemoglobin expressed as removal ratios. Secondary outcomes included platelet recovery and function and adverse events (clinical and device-related adverse events) up to 30 days after surgery. The study included 50 patients, of whom 18 (35%) underwent isolated coronary artery bypass graft, 26 (52%) valve surgery, and 6 (12%) aortic root surgery. The median red blood cell recovery per cycle was 86.1% (25th percentile to 75th percentile interquartile range, 80.8 to 91.6) with posttreatment hematocrit of 41.8% (39.7 to 44.2). Removal ratios for heparin and free hemoglobin were 98.9% (98.2 to 99.7) and 94.6% (92.7 to 96.6), respectively. No adverse device effect was reported. Median platelet recovery was 52.4% (44.2 to 60.1), with a posttreatment concentration of 116 (93 to 146) · 109/l. Platelet activation state and function, evaluated by flow cytometry, were found to be unaltered by the device. In this first-in-human study, the same™ device was able to simultaneously recover and wash both platelets and red blood cells. Compared with preclinical evaluations, the device achieved a higher platelet recovery of 52% with minimal platelet activation while maintaining platelet ability to be activated in vitro

    Epinephrine restores platelet functions inhibited by ticagrelor: A mechanistic approach

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    International audienceTicagrelor, an antagonist of the platelet adenosine diphosphate (ADP)-P2Y(12) receptor is recommended for patients with acute coronary syndromes. However, ticagrelor exposes to a risk of bleeding, the management of which is challenging because platelet transfusion is ineffective, and no antidote is yet available. We hypothesized that the vasopressor drug epinephrine could counter the antiplatelet effects of ticagrelor and restore platelet functions. We assessed in vitro the efficiency of epinephrine in restoring platelet aggregation inhibited by ticagrelor and investigated the underlying mechanisms. Washed platelet aggregation and secretion were measured upon stimulation by epinephrine alone or in combination with ADP, in the presence or absence of ticagrelor. Mechanistic investigations used P2Y(1) and phosphoinositide 3-kinase (PI3K) inhibitors and included vasodilator-stimulated phosphoprotein (VASP) and Akt phosphorylation assays as well as measurement of Ca2+ mobilisation. We found that epinephrine restored ADP-induced platelet aggregation, but not dense granule release. Epinephrine alone failed to induce aggregation whereas it fully induced VASP dephosphorylation and Akt phosphorylation regardless of the presence of ticagrelor. In the presence of ticagrelor, blockage of the P2Y(1) receptor prevented restoration of platelet aggregation by the combination of epinephrine and ADP, as well as intracellular Ca2+ mobilisation. In combination with ADP, epinephrine induced platelet aggregation of ticagrelor-treated platelets through inhibition of the CAMP pathway and activation of the PI3K pathway, thus enabling the P2Y(1) receptor signalling and subsequent Ca2+ mobilisation. This proof-of-concept study needs to be challenged in vivo for the management of bleeding in ticagrelor-treated patients
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