La Résistance aux antibiotiques chez les streptocoques d'origine animale (étude bibliographique)

LYON1-BU Santé (693882101) / SudocSudocFranceF

Cardiovascular devices: Mechanical characterization of coronary stents

Background: Coronary stents participate to limit cardiovascular death but are associated with some complications. Matching stent biomechanical characteristics with specific coronary lesions could limit these complications.Objectives: Development of a standardized and global bench test protocol and evaluation of most currently used coronary stents to improve stent choice in cathlab.Materials: We evaluated biomechanical characteristics of coronary stents (AbsorbTM-ABBOTT (R), Xience AlpineTM-ABBOTT (R), Resolute IntegrityTM-MEDTRONIC (R), Resolute OnyxTM-MEDTRONIC (R), OrsiroTM-BIOTRONIK (R), SynergyTM-BOSTON SCIENTIFIC (R), OptimaxTM-HEXACATH (R)) in an in vitro study: radial elastic recoil, foreshortening, crimped stent with balloon flexibility and deployed stent flexibility. We also evaluated maximal resistance, elastic strength limit and elastic deformation limit for radial and longitudinal compression. Stentswere deployed in a saline solution at 37+/-0.5 °C. 9 stents were used to evaluate elastic recoil and foreshortening. Then, 3 among them were used to evaluate radial resistance between parallel plates, 3 were used to evaluate longitudinal resistance and 3 others were used to evaluate deployed stent bending stiffness. Before stent inflation 3 stents, among the 9 devices dedicated to biomechanical evaluation, were used to evaluate the uninflated stent with balloon bending stiffness. For a maximum comparability between stent models, we chose the most used stent size in our clinical practice (3.0 mm diameter and the nearest to 20 mm length). For these evaluations, all devices were inflated with them own balloon, at nominal pressure, according to manufacturer's recommendations. Nominal pressure was maintained for 30 seconds. We studied coating with field emission gun scanning electron microscope after POT-SIDE-POT (PSP) simulation to evaluate coating resistance to angioplasty. Bifurcation performances were evaluated by microcomputed tomography imaging of PSP stented silicon bifurcation models. Statistical analyses were performed using XLStats 2017 (Addinsoft).Results: Elastic recoil, deployed stent exibility and crimped stent flexibility were signicantly different between groups (all p < 0.0001); as were radial and longitudinal maximum resistance (p < 0.0001). SynergyTM, OrsiroTM and Xience AlpineTM had the lowest elastic recoil. SynergyTM and Resolute OnyxTM were the most exible. OptimaxTM had the highest radial and longitudinal resistance. Coating lesions after PSP were not signicantly different, excepted for OptimaxTM which had no coating lesion. In bifurcation model, side branch ostium coverage and malapposed strut ratio were signicantly different between groups (respectively, p = 0.01 and p = 0.004). Strut fractures were founded only in AbsorbTM.Conclusion: Currently used stents have very different biomechanical and bifurcation performance proles. Their choice had to be adapted to each coronary lesion particularity to improve coronary interventions results

Standardized bench test evaluation of coronary stents: Biomechanical characteristics

Objectives The purpose of the study was to develop a standardized and global bench test protocol to evaluate the biomechanical characteristics of the most currently used drug-eluting coronary stents. Background The use of coronary stents has contributed to the reduction of cardiovascular mortality but can be associated with specific complications. Improving the biomechanical matching between the stents and the coronary anatomy may reduce these complications. Methods We assessed five commercially available drug-eluting stents: the Absorb, Orsiro, Resolute Onyx, Synergy, and Xience Alpine stents. Following stent deployment at nominal pressure in ambient air, radial elastic recoil and foreshortening were measured. Flexibility (crimped and deployed stents) and longitudinal and radial resistances were evaluated using a mechanical tester. Results Biomechanical characteristics were significantly different for all tested devices (ANOVA, P < 0.01). The Synergy, Orsiro, and Xience Alpine stents presented the lowest elastic recoil. The Synergy and Resolute Onyx stents were the most flexible devices. The Xience Alpine and Absorb stents had the highest longitudinal and radial resistances. Conclusions Drug-eluting coronary stents used in current clinical practice have very different biomechanical characteristics, which should be taken into consideration to select the most appropriate device for each clinical situation

Reciprocity Between Skeletal Muscle AMPK Deletion and Insulin Action in Diet-Induced Obese Mice

International audienceInsulin resistance due to overnutrition places a burden on energy-producing pathways in skeletal muscle (SkM). Nevertheless, energy state is not compromised. The hypothesis that the energy sensor AMP-activated protein kinase (AMPK) is necessary to offset the metabolic burden of overnutrition was tested using chow-fed and high fat (HF)-fed SkM-specific AMPKα1α2 knockout (mdKO) mice and AMPKα1α2lox/lox littermates (WT). Lean mdKO and WT mice were phenotypically similar. HF-fed mice were equally obese and maintained lean mass regardless of genotype. Results did not support the hypothesis that AMPK is protective during overnutrition. Paradoxically, mdKO mice were more insulin sensitive. Insulin-stimulated SkM glucose uptake was ∼two-fold greater in mdKO mice in vivo. Furthermore, insulin signaling, SkM GLUT4 translocation, hexokinase activity, and glycolysis were increased. AMPK and insulin signaling intersect at mTOR, a critical node for cell proliferation and survival. Basal mTOR activation was reduced by 50% in HF-fed mdKO mice, but was normalized by insulin-stimulation. Mitochondrial function was impaired in mdKO mice, but energy charge was preserved by AMP deamination. Results show a surprising reciprocity between SkM AMPK signaling and insulin action that manifests with diet-induced obesity, as insulin action is preserved to protect fundamental energetic processes in the muscle

Effect and Safety of Morphine Use in Acute Anterior ST‐Segment Elevation Myocardial Infarction

International audienceBackground: Morphine is commonly used to treat chest pain during myocardial infarction, but its effect on cardiovascular outcome has never been directly evaluated. The aim of this study was to examine the effect and safety of morphine in patients with acute anterior ST‐segment elevation myocardial infarction followed up for 1 year.Methods and Results: We used the database of the CIRCUS (Does Cyclosporine Improve Outcome in ST Elevation Myocardial Infarction Patients) trial, which included 969 patients with anterior ST‐segment elevation myocardial infarction, admitted for primary percutaneous coronary intervention. Two groups were defined according to use of morphine preceding coronary angiography. The composite primary outcome was the combined incidence of major adverse cardiovascular events, including cardiovascular death, heart failure, cardiogenic shock, myocardial infarction, unstable angina, and stroke during 1 year. A total of 554 (57.1%) patients received morphine at first medical contact. Both groups, with and without morphine treatment, were comparable with respect to demographic and periprocedural characteristics. There was no significant difference in major adverse cardiovascular events between patients who received morphine compared with those who did not (26.2% versus 22.0%, respectively; P=0.15). The all‐cause mortality was 5.3% in the morphine group versus 5.8% in the no‐morphine group (P=0.89). There was no difference between groups in infarct size as assessed by the creatine kinase peak after primary percutaneous coronary intervention (4023±118 versus 3903±149 IU/L; P=0.52).Conclusions: In anterior ST‐segment elevation myocardial infarction patients treated by primary percutaneous coronary intervention, morphine was used in half of patients during initial management and was not associated with a significant increase in major adverse cardiovascular events at 1 year

Pheochromocytoma surgery without systematic preoperative pharmacological preparation: insights from a referral tertiary center experience

International audienc

Development of automated measures of indicators of wellbeing and health of poultry: special case of avian infectious bronchitis

International audienc

Impact d'une exposition périnatale au sucre et au gras via le régime maternel sur le comportement, les adaptations, métaboliques et cérébrales de miniporcs Yucatan

National audienceIntroduction: A lot of evidences defend the existence of a relationship between a Western diet and the increase of obesity prevalence (OMS, 2011). Particularly, the quality of early nutrition has a long-term impact on the offspring’s phenotype and health status (Barker, 1989). The aim of our study was to explore in the Yucatan minipig model the impact of the maternal diet (High Fat Fructose diet, HFF versus standard diet, STD) during pregnancy and lactation on the cognitive and hedonic functions of the offspring at the adult age, through behavioural assessments and brain imaging, combined with metabolic and physiological explorations. A challenge with an obesogenic diet was then performed to assess its effects on eating behaviour, weight gain and blood parameters.Material & methods: Learning and memory performances were tested using the holeboard discrimination task, with a palatable food reward (M&M’s®), and an Alley maze test, independent from food reward. Eating behaviour was explored with a two-choice feed test and an operant conditioning test with progressive ratio. In parallel, the brain basal glucose metabolism was investigated using Positron Emission Tomography (PET) and the dopaminergic brain reward system (in particular the striatum) was explored using DAT-scan imaging. Biologic samples were collected for blood profiles and analysis of the gut microbiota activity (FFA).Results: We showed that early nutrition could indirectly impact cognitive performances, modulating the emotional status in a high-anxiogenic/low-motivating (maze) situation, but not in low-anxiogenic/high-motivating situation (holeboard). As a matter of fact, STD better succeeded in the maze, whereas no difference appeared during the holeboard test. During the feeding tests, HFF showed a tendency to eat more than STD group. Brain sub-activations in the anterior prefrontal cortex and accumbens nucleus, as well as impairment of the striatal dopaminergic system were observed, which may explain eating behavior differences between HFF and STD. On the other hand, HFF presented better lipids profiles than STD. After an obesogenic challenge, we surprisingly observed that STD ate and gained more weight than HFF, while HFF inflammatory status was higher than STD. Conclusion: All these results suggest that HFF maternal western diet had a deleterious impact on the neurocognitive functions, in a high stressful situation, of the offspring and modulated its responses to an obesogenic dietary challenge.Key words: nutritional imprinting, behavior, brain, reward system, memory, learning, minipig

Mitral transcatheter edge to edge repair versus isolated mitral surgery for severe mitral regurgitation: A French nationwide study

International audienceBackground and aims: Mitral valve surgery and more recently mitral transcatheter edge-to-edge repair (TEER) are the two treatments of severe mitral regurgitation in eligible patients. Clinical comparison of both therapies remains limited by the number of patients analysed. The objective of this study was to analyse the outcomes of mitral TEER versus isolated mitral valve surgery at a nationwide level in France.Methods: Based on the French administrative hospital-discharge database, the study collected information for all consecutive patients treated for mitral regurgitation with isolated TEER or isolated mitral valve surgery between 2012 and 2022. Propensity score matching was used for the analysis of outcomes.Results: A total of 57,030 patients were found in the database. After matching on baseline characteristics, 2,160 patients were analysed in each arm. At 3-year follow-up, TEER was associated with significantly lower incidence of cardiovascular death (HR 0.685, 95% CI 0.563-0.832; p &lt; 0.001), pacemaker implantation and stroke. Non-cardiovascular death (HR 1.562, 95% CI 1.238-1.971; p = 0.0001), recurrent pulmonary edema and cardiac arrest were more frequent after TEER. No significant differences between the two groups were observed regarding all-cause death (HR 0.967, 95% CI 0.835-1.118; p = 0.65), endocarditis, major bleeding and atrial fibrillation and myocardial infarction.Conclusions: Our results suggest that TEER for severe mitral regurgitation was associated with lower cardiovascular mortality than mitral surgery at long-term follow-up. Pacemaker implantation and stroke were less frequently observed after TEER

Ret kinase-mediated mechanical induction of colon stem cells by tumor growth pressure stimulates cancer progression in vivo

International audienceHow mechanical stress actively impacts the physiology and pathophysiology of cells and tissues is little investigated in vivo. The colon is constantly submitted to multi-frequency spontaneous pulsatile mechanical waves, which highest frequency functions, of 2 s period, remain poorly understood. Here we find in vivo that high frequency pulsatile mechanical stresses maintain the physiological level of mice colon stem cells (SC) through the mechanosensitive Ret kinase. When permanently stimulated by a magnetic mimicking-tumor growth analogue pressure, we find that SC levels pathologically increase and undergo mechanically induced hyperproliferation and tumorigenic transformation. To mimic the high frequency pulsatile mechanical waves, we used a generator of pulsed magnetic force stimulation in colonic tissues pre-magnetized with ultra-magnetic liposomes. We observed the pulsatile stresses using last generation ultra-wave dynamical high-resolution imaging. Finally, we find that the specific pharmacological inhibition of Ret mechanical activation induces the regression of spontaneous formation of SC, of CSC markers, and of spontaneous sporadic tumorigenesis in Apc mutated mice colons. Consistently, in human colon cancer tissues, Ret activation in epithelial cells increases with tumor grade, and partially decreases in leaking invasive carcinoma. High frequency pulsatile physiological mechanical stresses thus constitute a new niche that Ret-dependently fuels mice colon physiological SC level. This process is pathologically over-activated in the presence of permanent pressure due to the growth of tumors initiated by pre-existing genetic alteration, leading to mechanotransductive selfenhanced tumor progression in vivo, and repressed by pharmacological inhibition of Ret