F015 Role des fibroblastes cardiaques dans la tolérance des cardiomyocytes à l’ischémie reperfusion

ObjectifLes fibroblastes cardiaques sont la population cellulaire majoritaire du tissu cardiaque. Leurs possibles implications au cours de la séquence ischémie-reperfusion n’a jamais été étudiée. Le présent travail a donc pour but de déterminer si les fibroblastes sont impliqués dans une modulation de la cardioprotection.Matériel et MéthodesNous avons utilisé dans cette étude un modèle de cardiomyocytes de rats nouveau-nés soumis à une séquence d’ischémie-reperfusion simulées. Les cellules ont été isolées à partir de ventricules de rats nouveau nés. Les myocytes cardiaques ont été purifiés par attachements différentiels puis cultivés en présence d’un milieu de culture supplémenté en cytosine arabinoside (Ara C, 10μm). Les cardiomyocytes et les fibroblastes ont été cultivés séparément puis placés en contact direct (cultures mixtes) ou indirect (insert). Ces co-cultures ont subi une ischémie de 3H en absence de nutriments et d’O2 suivie d’une reperfusion de 20H en présence de nutriments et d’O2. Des tests de viabilité (test MTT) et de mortalité cellulaire (dosage de l’activité LDH et Troponine I) ont été effectués à la fin de la reperfusion.RésultatsNous avons montré qu’il était possible de simuler des séquences d’ischémie reperfusion et d’induire une souffrance cellulaire détectable pour une durée d’ischémie de 3H et de reperfusion de 20H. Dans les cultures mixtes (cardiomyocytes + fibroblastes), les tests MTT et LDH ont montré une amélioration de la viabilité cellulaire globale en comparaison avec la viabilité spécifique de chaque type cellulaire seul. Pour les cultures placées en insert, les tests MTT et Troponine I ont montré une amélioration de la viabilité des cardiomyocytes en présence des fibroblastes (p<0.001).ConclusionsNos résultats indiquent que les fibroblastes cardiaques semblent être impliqués dans une modulation de la cardioprotection lors de l’ischémie reperfusion. Cette modulation passe au moins en partie par des mécanismes de type paracrine et elle est dépendante de la quantité de fibroblastes en co-culture avec les cardiomyocytes

D010 Mesenchymal stem cells protect cardiomyocytes from reperfusion injury through a paracrine activation of the PI3 kinase pathway

ObjectivesPrevious data suggest that implantation of mesenchymal stem cells (MSCs) improves heart function after myocardial infarction. We investigated whether protection afforded by MSCs might involve a paracrine activation of the PI3 kinase pathway in reperfused cardiomyocytes.MethodMSCs and neonatal rat cardiomyocytes (NRCs) were isolated and cultured separately. NRCs (2.106) were subjected to 5 hours of ischemia followed by 16 hours of reperfusion. At the time of reperfusion, NRCs (n=8-14/group) received either fresh medium (control group), or the following treatments: MSCs (2.105 MSCs in fresh medium), conditioned SN (MSCs supernatant alone (i.e. without MSCs) obtained after 8 hours of serum deprived culture), [conditioned SN + LY294002] (15 microM of LY294002 a specifi c inhibitor of PI3K), [conditioned SN + Wortmannin] (100 nM of wortmannin, a non specifi c inhibitor of PI3K), or CsA (200 nM in fresh medium) a potent inhibitor of the mitochondrial permeability transition pore. Cell death was assessed by LDH release in NRCs supernatant at the end of reperfusion.ResultsAs expected, LDH activity was dramatically reduced by CsA, averaging 4 % of control values. LDH activity was signifi cantly reduced by MSCs alone and by conditioned SN, averaging 29 % and 12 % of control value, respectively. Both LY294002 and wortmannin signifi cantly attenuated conditioned SN induced protection.Conclusionour data suggest that MSCs can protect NRCs from reperfusion injury through a paracrine activation of the PI3K pathway

The Rewiring of Ubiquitination Targets in a Pathogenic Yeast Promotes Metabolic Flexibility, Host Colonization and Virulence

Funding: This work was funded by the European Research Council [http://erc.europa.eu/], AJPB (STRIFE Advanced Grant; C-2009-AdG-249793). The work was also supported by: the Wellcome Trust [www.wellcome.ac.uk], AJPB (080088, 097377); the UK Biotechnology and Biological Research Council [www.bbsrc.ac.uk], AJPB (BB/F00513X/1, BB/K017365/1); the CNPq-Brazil [http://cnpq.br], GMA (Science without Borders fellowship 202976/2014-9); and the National Centre for the Replacement, Refinement and Reduction of Animals in Research [www.nc3rs.org.uk], DMM (NC/K000306/1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Acknowledgments We thank Dr. Elizabeth Johnson (Mycology Reference Laboratory, Bristol) for providing strains, and the Aberdeen Proteomics facility for the biotyping of S. cerevisiae clinical isolates, and to Euroscarf for providing S. cerevisiae strains and plasmids. We are grateful to our Microscopy Facility in the Institute of Medical Sciences for their expert help with the electron microscopy, and to our friends in the Aberdeen Fungal Group for insightful discussions.Peer reviewedPublisher PD

Disseminated tuberculosis presenting with polymorphonuclear effusion and septic shock in an HIV-seropositive patient: a case report

<p>Abstract</p> <p>Introduction</p> <p>Because a substantial number of patients present with few or atypical symptoms, the recognition of tuberculosis remains challenging. Disseminated tuberculosis presenting with septic shock has already been described in some case reports, but, to the best of our knowledge, it has never been associated with polymorphonuclear effusion.</p> <p>Case presentation</p> <p>We describe the case of a 27-year-old man from western Africa who was seropositive for human immunodeficiency virus. He presented with pleural and abdominal polymorphonuclear effusions and quickly developed septic shock due to disseminated <it>Mycobacterium tuberculosis </it>infection leading to multiple organ failure and death.</p> <p>Conclusion</p> <p>In high-risk patients, <it>Mycobacterium tuberculosis </it>infection should be considered even in exceptional clinical presentations, such as septic shock and polymorphonuclear effusions.</p

COVID-19 pandemic: Impact caused by school closure and national lockdown on pediatric visits and admissions for viral and non-viral infections, a time series analysis.

A time series analysis of 871,543 pediatric emergency visits revealed that the COVID-19 lockdown and school closure were associated with a significant decrease in infectious diseases disseminated through airborne or fecal-oral transmissions: common cold, gastro-enteritis, bronchiolitis, acute otitis. No change was found for urinary tract infections

Can we identify response markers to antihypertensive drugs? First results from the Ideal Trial

Current antihypertensive strategies do not take into account that individual characteristics may influence the magnitude of blood pressure (BP) reduction. Guidelines promote trial-and-error approaches with many different drugs. We conducted the Identification of the Determinants of the Efficacy of Arterial blood pressure Lowering drugs (IDEAL) Trial to identify factors associated with BP responses to perindopril and indapamide. IDEAL was a cross-over, double-blind, placebo-controlled trial, involving four 4-week periods: indapamide, perindopril and two placebo. Eligible patients were untreated, hypertensive and aged 25-70 years. The main outcome was systolic BP (SBP) response to drugs. The 112 participants with good compliance had a mean age of 52. One in every three participants was a woman. In middle-aged women, the SBP reduction from drugs was -11.5 mm Hg (indapamide) and -8.3 mm Hg (perindopril). In men, the response was significantly smaller: -4.8 mm Hg (indapamide) and -4.3 (perindopril) (P for sex differences 0.001 and 0.015, respectively). SBP response to perindopril decreased by 2 mm Hg every 10 years of age in both sexes (P=0.01). The response to indapamide increased by 3 mm Hg every 10 years of age gradient in women (P=0.02). Age and sex were important determinants of BP response for antihypertensive drugs in the IDEAL population. This should be taken into account when choosing drugs a priori.Journal of Human Hypertension advance online publication, 17 April 2014; doi:10.1038/jhh.2014.29

The Global Risk Approach Should Be Better Applied in French Hypertensive Patients: A Comparison between Simulation and Observation Studies

The prediction of the public health impact of a preventive strategy provides valuable support for decision-making. International guidelines for hypertension management have introduced the level of absolute cardiovascular risk in the definition of the treatment target population. The public health impact of implementing such a recommendation has not been measured.We assessed the efficiency of three treatment scenarios according to historical and current versions of practice guidelines on a Realistic Virtual Population representative of the French population aged from 35 to 64 years: 1) BP≥160/95 mm Hg; 2) BP≥140/90 mm Hg and 3) BP≥140/90 mm Hg plus increased CVD risk. We compared the eligibility following the ESC guidelines with the recently observed proportion of treated amongst hypertensive individuals reported by the Etude Nationale Nutrition Santé survey. Lowering the threshold to define hypertension multiplied by 2.5 the number of eligible individuals. Applying the cardiovascular risk rule reduced this number significantly: less than 1/4 of hypertensive women under 55 years and less than 1/3 of hypertensive men below 45 years of age. This was the most efficient strategy. Compared to the simulated guidelines application, men of all ages were undertreated (between 32 and 60%), as were women over 55 years (70%). By contrast, younger women were over-treated (over 200%).The global CVD risk approach to decide for treatment is more efficient than the simple blood pressure level. However, lack of screening rather than guideline application seems to explain the low prescription rates among hypertensive individuals in France. Multidimensional analyses required to obtain these results are possible only through databases at the individual level: realistic virtual populations should become the gold standard for assessing the impact of public health policies at the national level

Reappraisal of Metformin Efficacy in the Treatment of Type 2 Diabetes: A Meta-Analysis of Randomised Controlled Trials

Catherine Cornu and colleagues performed a meta-analysis of randomised controlled trials of metformin efficacy on cardiovascular morbidity or mortality in patients with type 2 diabetes and showed that although metformin is considered the gold standard, its benefit/risk ratio remains uncertain

Harmonizing and improving European education in prescribing: An overview of digital educational resources used in clinical pharmacology and therapeutics

Aim: Improvement and harmonization of European clinical pharmacology and therapeutics (CPT) education is urgently required. Because digital educational resources can be easily shared, adapted to local situations and re-used widely across a variety of educational systems, they may be ideally suited for this purpose. Methods: With a cross-sectional survey among principal CPT teachers in 279 out of 304 European medical schools, an overview and classification of digital resources was compiled. Results: Teachers from 95 (34%) medical schools in 26 of 28 EU countries responded, 66 (70%) of whom used digital educational resources in their CPT curriculum. A total of 89 of such resources were described in detail, including e-learning (24%), simulators to teach pharmacokinetics and/or pharmacodynamics (10%), virtual patients (8%), and serious games (5%). Together, these resources covered 235 knowledge-based learning objectives, 88 skills, and 13 attitudes. Only one third (27) of the resources were in-part or totally free and only two were licensed open educational resources (free to use, distribute and adapt). A narrative overview of the largest, free and most novel resources is given. Conclusion: Digital educational resources, ranging from e-learning to virtual patients and games, are widely used for CPT education in EU medical schools. Learning objectives are based largely on knowledge rather than skills or attitudes. This may be improved by including more real-life clinical case scenarios. Moreover, the majority of resources are neither free nor open. Therefore, with a view to harmonizing international CPT education, more needs to be learned about why CPT teachers are not currently sharing their educational materials