19 research outputs found
Position of the Polar Front along the western Iberian margin during key cold episodes of the last 45 ka
This paper documents the migration of the Polar Front (PF) over the Iberian margin during some of the cold climatic extremes of the last 45 ka. It is based on a compilation of robust and coherent paleohydrological proxies obtained from eleven cores distributed between 36 and 42°N. Planktonic δ18O (Globigerina bulloides), ice-rafted detritus concentrations, and the relative abundance of the polar foraminifera Neogloboquadrina pachyderma sinistral were used to track the PF position. These three data sets, compared from core to core, show a consistent evolution of the sea surface paleohydrology along the Iberian margin over the last 45 ka. We focused on five time slices representative of cold periods under distinct paleoenvironmental forcings: the 8.2 ka event and the Younger Dryas (two recent cold events occurring within high values of summer insolation), Heinrich events 1 and 4 (reflecting major episodes of massive iceberg discharges into the North Atlantic), and the Last Glacial Maximum (typifying the highest ice volume accumulated in the Northern Hemisphere). For each event, we generated schematic maps mirroring past sea surface hydrological conditions. The maps revealed that the Polar Front presence along the Iberian margin was restricted to Heinrich events. The sea surface conditions during the Last Glacial Maximum were close to those at present day, except for the northern sites which briefly experienced subarctic conditions
Cryoablation au ballonnet de la fibrillation atriale paroxystique (expérience initiale au CHU de Rouen)
L'ablation percutanée est actuellement reconnue comme un traitement efficace de la fibrillation atriale (FA) chez les patients présentant une FA symptomatique résistante au traitement antiarythmique. L'isolation des veines pulmonaires par radiofréquence est la technique de référence mais son utilisation peut être source de complications, potentiellement sévères. L'objectif de cette étude est d'évaluer à court et à moyen terme l'efficacité et la sûreté d'un nouveau cathéter utilisant un ballonnet de cryothérapie (Arctic Front®, Cryocath, Quebec, Canada). METHODE: Entre Décembre 2007 et Avril 2009, 37 patients (25 hommes, d'âge moyen 56 ans) porteurs d'une FA symptomatique, paroxystique (n= 36) ou persistante (n=1), et résistante au traitement antiar,.thmique ont bénéficié d'une isolation des veines pulmonaires par cryothérapie au ballonnet (23 ou 28 mm). Pendant l'hospitalisation, un Holter-ECG, une échocardiographie ainsi qu'une fibroscopie œsogastroduodénale ont été réalisées. Tous les patients ont également bénéficié d'une IRNf des veines pulmonaires avant la procédure et à 3 mois. En cas de récidive symptomatique de la FA. une 2ème procédure a été réalisée par radiofréquence. RESULTATS: Sur les 148 veines pulmonaires ablatées, 138 ont été isolées avec succès (93.2 %), ce qui correspond à 73 % des patients (n=27). Chez les 10 autres patients, l'isolation n'était que partielle avec persistance d'une conduction résiduelle sur une veine pulmonaire, le plus souvent la veine pulmonaire inférieure droite (n=8). Le nombre moyen de cryoapplications par veine est de 2.2 +- 0.7 et les temps moyens de procédure et de scopie de 164.1 +- 38.8 et 31.4 +- 12.2 minutes respectivement. A la sortie de l'hôpital, 97.3% (n=36) des patients sont en rythme sinusal. Aucune sténose des veines pulmonaires, fistule oeso-atriale ou évènement thromboembolique n'est relevé. L'évènement indésirable le plus sévère est la survenue de 4 paralysies phréniques (10,8 %), dont 3 résolutives immédiatement après arrêt des tirs de cryothérapie et 1 à 15 jours. Au terme d'un suivi moyen de 158 +/- 70 jours, le maintien du rythme sinusal est obtenu chez 64,9 % des patients (45.9 % sans traitement antiarythmique). Les facteurs prédictifs d'échec de la procédure en analyse multivariée sont la présence d'un score de CHADS2>= 1 (p= 0.046) et la récidive précoce de FA (p= 0.0035). CONCLUSION: L'isolation des veines pulmonaires par cryothérapie au ballonnet semble être une technique sûre et efficace avec un taux de succès satisfaisant à 4 mois.ROUEN-BU Médecine-Pharmacie (765402102) / SudocSudocFranceF
201 Pulmonary vein isolation by cryoballoon ablation in patients with paroxysmal atrial fibrillation: efficacy, safety and predictors of arrhythmia recurrence
IntroductionRadiofrequency (RF) catheter ablation has emerged as an effective treatment for patients with drug-refractory atrial fibrillation (AF). The objective of this study is to evaluate the efficacy and safety of pulmonary vein isolation (PVI) with a cryoballoon catheter (Arctic Front, Cryocath, Quebec, Canada).MethodsIn 44 consecutive patients with symptomatic paroxysmal AF (28 males, age 57 +/− 11 years), circumferential PVI was performed using a cryoballoon catheter. Before discharge, all patients were subjected to 24-hour Holter electrocardiograms, echocardiography, and esophageal endoscopy. Magnetic resonance imaging was performed prior to and 3 months after ablation. At a mean follow up of 4.3 +/− 1.2 months after ablation, patients underwent clinical review and 24-hour Holter electrocardiograms. Clinical and demographic variables were analyzed via logistic regression to assess for predictors of recurrence.ResultsThirty-two of the 44 patients (73%) had complete isolation of all PVs. Out of 176 treated veins, 164 were completely isolated (93%). The number of balloon applications per vein was 2.3±0.8. The mean procedure and fluoroscopy times were 163.4±36.2 and 32.0±11.7min, respectively. Eight patients had evidence of mild pericardial effusions requiring no further treatment. Five patients (11.4%) experienced phrenic nerve palsy, 4 of which resolved immediately and one at 2 weeks. Follow up at 4.3 +/− 1.2 months showed freedom from AF in 28 patients (63.6%) and freedom from AF without antiarrhythmic drug therapy in 19 patients (43.2%). Of all clinical variables analyzed, only early recurrence of AF within 4 days post ablation was associated with long term AF recurrence (p=0.002; OR=0.11; CI=[0.018–0.524]).ConclusionPVI can be safely achieved with the cryoballoon catheter with a moderate success rate at 4.3 months follow-up. Early recurrence of AF seems to be a clinical predictor for long term atrial fibrillation recurrence
Induction of adiponectin in skeletal muscle of type 2 diabetic mice: In vivo and in vitro studies.
AIMS/HYPOTHESIS: Adiponectin is an adipokine that exhibits insulin-sensitising, fat-burning and anti-inflammatory properties as well as modulatory effects on oxidative stress. We examined whether adiponectin could be induced in a non-adipose tissue, skeletal muscle, in response to metabolic or oxidative aggression both in vivo (in a murine model of type 2 diabetes) and in vitro. METHODS: Obese and diabetic ob/ob mice were used and compared with lean littermates. Some obese mice were treated with the antioxidant probucol for 3 weeks. At the end of the experiment, blood was sampled and tibialis anterior muscles were collected for mRNA measurement and immunohistochemistry. Additional in vitro experiments were performed on C2C12 myotubes cultured for up to 48 h. RESULTS: In spite of hypoadiponectinaemia, Adipoq mRNA levels were markedly increased in the skeletal muscle of ob/ob mice and correlated with systemic oxidative stress. Adipoq upregulation was shown in laser-microdissected myocytes of obese mice. Concomitantly, immunoreactivity for adiponectin was enhanced in obese muscle fibres together with lipid infiltration and local markers of oxidative stress. In cultured C2C12 myotubes, a triglyceride mix and reactive oxygen species producers (H2O2 or a lipoperoxidation end-product) upregulated Adipoq expression and adiponectin production. This effect was reversed by an antioxidant. Finally, treatment of obese mice with probucol also attenuated upregulation in muscle. CONCLUSIONS/INTERPRETATION: The paradoxical upregulation of adiponectin in muscle of obese and diabetic mice may result from lipotoxicity and related oxidative stress. This unexpected finding could be viewed as a local protection to counteract ectopic fat deposition and oxidative damage
YKL-40 as a new promising prognostic marker of severity in COVID infection.
peer reviewe
Combined score using clinical, electrocardiographic, and echocardiographic parameters to predict left ventricular remodeling in patients having had cardiac resynchronization therapy six months earlier.
International audienceThe aim of this study was to evaluate whether a scoring system integrating clinical, electrocardiographic, and echocardiographic measurements can predict left ventricular reverse remodeling after cardiac resynchronization therapy (CRT). The derivation cohort consisted of 162 patients with heart failure implanted with a CRT device. Baseline clinical, electrocardiographic, and echocardiographic characteristics were entered into univariate and multivariate models to predict reverse remodeling as defined by a ≥15% reduction in left ventricular end-systolic volume at 6 months (60%). Combinations of predictors were then tested under different scoring systems. A new 7-point CRT response score termed L2ANDS2: Left bundle branch block (2 points), Age >70 years, Nonischemic origin, left ventricular end-diastolic Diameter 5 had a high positive likelihood ratio (+LR = 5.64), whereas a score <2 had a high negative likelihood ratio (-LR = 0.19). In conclusion, this L2ANDS2 score provides an easy-to-use tool for the clinician to assess the pretest probability of a patient being a CRT responder
[Giant pulmonary artery aneurysms. Case report and proposal of management algorithm].
Pulmonary artery aneurysm is a rare and multiform pathology related to multiple etiologies and therefore different pathophysiological mechanisms. Delineating homogenous sub-groups is a pre-requisite to refine medico-surgical management. The case of a giant PAA without pulmonary hypertension but associated to a dysplastic pulmonary valve is reported. This association could be in some instances the result of a congenital anomaly in the development of both the pulmonary valve and the root creating the conditions for further development of a pulmonary artery aneurysm. Whilst minor forms are usually asymptomatic, they can lead to lethal complications in huge sizes and are frequently associated via pulmonary valve insufficiency to right ventricular dysfunction. This specific association is discussed and a diagnostic algorithm for nosologic classification and management is proposed
Could KL-6 levels in COVID-19 help to predict lung disease?
BACKGROUND: Coronavirus disease COVID-19 has become a public health emergency of international concern. Together with the quest for an effective treatment, the question of the post-infectious evolution of affected patients in healing process remains uncertain. Krebs von den Lungen 6 (KL-6) is a high molecular weight mucin-like glycoprotein produced by type II pneumocytes and bronchial epithelial cells. Its production is raised during epithelial lesions and cellular regeneration. In COVID-19 infection, KL-6 serum levels could therefore be of interest for diagnosis, prognosis and therapeutic response evaluation. MATERIALS AND METHODS: Our study retrospectively compared KL-6 levels between a cohort of 83 COVID-19 infected patients and two other groups: healthy subjects (n = 70) on one hand, and a heterogenous group of patients suffering from interstitial lung diseases (n = 31; composed of 16 IPF, 4 sarcoidosis, 11 others) on the other hand. Demographical, clinical and laboratory indexes were collected. Our study aims to compare KL-6 levels between a COVID-19 population and healthy subjects or patients suffering from interstitial lung diseases (ILDs). Ultimately, we ought to determine whether KL-6 could be a marker of disease severity and bad prognosis. RESULTS: Our results showed that serum KL-6 levels in COVID-19 patients were increased compared to healthy subjects, but to a lesser extent than in patients suffering from ILD. Increased levels of KL-6 in COVID-19 patients were associated with a more severe lung disease. DISCUSSION AND CONCLUSION: Our results suggest that KL-6 could be a good biomarker to assess ILD severity in COVID-19 infection. Concerning the therapeutic response prediction, more studies are necessary
Relationship of the SAMe-TT 2 R 2 Score to Poor-Quality Anticoagulation, Stroke, Clinically Relevant Bleeding, and Mortality in Patients With Atrial Fibrillation
International audienc
Endothelial extracellular vesicles promote tumour growth by tumour-associated macrophage reprogramming.
Tumour-derived extracellular vesicles (EVs) participate in tumour progression by deregulating various physiological processes including angiogenesis and inflammation. Here we report that EVs released by endothelial cells in a mammary tumour environment participate in the recruitment of macrophages within the tumour, leading to an immunomodulatory phenotype permissive for tumour growth. Using RNA-Seq approaches, we identified several microRNAs (miRNAs) found in endothelial EVs sharing common targets involved in the regulation of the immune system. To further study the impact of these miRNAs in a mouse tumour model, we focused on three miRNAs that are conserved between humans and mouse, that is, miR-142-5p, miR-183-5p and miR-222-3p. These miRNAs are released from endothelial cells in a tumour microenvironment and are transferred via EVs to macrophages. In mouse mammary tumour models, treatment with EVs enriched in these miRNAs leads to a polarization of macrophages toward an M2-like phenotype, which in turn promotes tumour growth