5-Methylcytosine and 5-Hydroxymethylcytosine Spatiotemporal Profiles in the Mouse Zygote

Background: In the mouse zygote, DNA methylation patterns are heavily modified, and differ between the maternal and paternal pronucleus. Demethylation of the paternal genome has been described as an active and replication-independent process, although the mechanisms responsible for it remain elusive. Recently, 5-hydroxymethylcytosine has been suggested as an intermediate in this demethylation. Methodology/principal findings: In this study, we quantified DNA methylation and hydroxymethylation in both pronuclei of the mouse zygote during the replication period and we examined their patterns on the pericentric heterochromatin using 3D immuno-FISH. Our results demonstrate that 5-methylcytosine and 5-hydroxymethylcytosine localizations on the pericentric sequences are not complementary; indeed we observe no enrichment of either marks on some regions and an enrichment of both on others. In addition, we show that DNA demethylation continues during DNA replication, and is inhibited by aphidicolin. Finally, we observe notable differences in the kinetics of demethylation and hydroxymethylation; in particular, a peak of 5-hydroxymethylcytosine, unrelated to any change in 5-methylcytosine level, is observed after completion of replication. Conclusion/significance: Together our results support the already proposed hypothesis that 5-hydroxymethylcytosine is not a simple intermediate in an active demethylation process and could play a role of its own during early development

Similar effect of co-administration of methotrexate and folic acid for the treatment of arthritis compared to separate administration

International audienceAbstract Objectives MTX is the recommended first-line treatment for RA associated with folic acid (FA) to reduce side effects related to MTX. Here, we proposed to test a co-administration of MTX with FA in the rat adjuvant-induced arthritis (AIA) on efficacy. Material and methods AIA was induced in female Lewis rats and treated with MTX in three groups. The first group of rats received only MTX (n = 13), whereas the second received MTX and FA on the same day (n = 14). The third group received FA one day after MTX (n = 14). Arthritic index (AI), ankle circumference (AC), ankle microcomputed tomography, and blood tests assessed arthritis severity and MTX tolerance. Results AI and AC were similar in MTX groups at various time points. Bone erosion and bone loss parameters were similar in all groups. MTX-PG1 was found at similar levels in various MTX groups and correlated negatively with arthritis severity. Finally, haematology and metabolic parameters were found at a similar level in MTX groups. Conclusion Co-administration of MTX with FA on the same day did not reduce efficacy compared with FA application one day after MTX. Thus, co-administration of MTX and FA could be more convenient and improve compliance in patients

Clinical outcome of degenerative mitral regurgitation critical importance of echocardiographic quantitative assessment in routine practice

BACKGROUND: Echocardiographic quantitation of degenerative mitral regurgitation (DMR) is recommended whenever possible in clinical guidelines but is criticized and its scalability to routine clinical practice doubted. We hypothesized that echocardiographic DMR quantitation, performed in routine clinical practice by multiple practitioners, predicts independently long-term survival and thus is essential to DMR management. METHODS: We included patients diagnosed with isolated mitral valve prolapse from 2003 to 2011 and any degree of mitral regurgitation quantified by any physician/sonographer in routine clinical practice. Clinical/echocardiographic data acquired at diagnosis were retrieved electronically. The end point was mortality under medical treatment analyzed by Kaplan-Meier method and proportional hazard models. RESULTS: The cohort included 3914 patients (55% male) mean age (\ub1standard deviation) 62\ub117 years with left ventricular ejection fraction 63\ub18% and median after routinely-measured effective regurgitant orifice area (EROA) [interquartile range], 19 [0-40] mm2. During follow-up (6.7\ub13.1 years), 696 patients died under medical management, and 1263 underwent mitral surgery. In multivariate analysis, routinely-measured EROA was associated with mortality (adjusted hazard ratio, 1.19; 95% confidence interval, 1.13-1.24; P<0.0001 per 10 mm2) independently of left ventricular ejection fraction and end-systolic diameter, symptoms, and age/comorbidities. The association between routinely-measured EROA and mortality persisted with competitive risk modeling (adjusted hazard ratio, 1.15; 95% confidence interval, 1.10-1.20; P<0.0001 per 10 mm2), or in patients without guideline-based class I/II surgical triggers (adjusted hazard ratio, 1.19; 95% confidence interval, 1.10-1.28; P<0.0001 per 10 mm2) and in all subgroups examined (all P<0.01). Spline curve analysis showed that, compared with general population mortality, excess mortality appears for moderate DMR (EROA 6520 mm2), becomes notable at EROA 6530 mm2, and steadily increases with higher EROA levels (eg, higher EROA levels beyond the 40 mm2 threshold). CONCLUSIONS: Echocardiographic DMR quantitation is scalable to routine practice and is independently associated with clinical outcome. Routinely-measured EROA is strongly associated with long-term survival under medical treatment. Excess mortality versus the general population appears in the moderate DMR range and steadily increases with higher EROA. Hence, individual EROA values should be integrated into therapeutic considerations, in addition to categorical DMR grading

Pathophysiology of Degenerative Mitral Regurgitation: New 3-Dimensional Imaging Insights

Despite its high prevalence, little is known about mechanisms of mitral regurgitation in degenerative mitral valve disease apart from the leaflet prolapse itself. Mitral valve is a complex structure, including mitral annulus, mitral leaflets, papillary muscles, chords, and left ventricular walls. All these structures are involved in physiological and pathological functioning of this valvuloventricular complex but up to now were difficult to analyze because of inherent limitations of 2-dimensional imaging. The advent of 3-dimensional echocardiography, computed tomography, and cardiac magnetic resonance imaging overcoming these limitations provides new insights into mechanistic analysis of degenerative mitral regurgitation. This review will detail the contribution of quantitative and qualitative dynamic analysis of mitral annulus and mitral leaflets by new imaging methods in the understanding of degenerative mitral regurgitation pathophysiology

Presentation and Outcome of Arrhythmic\ua0Mitral Valve Prolapse

Mitral valve prolapse (MVP) is often considered benign but recent suggestion of an arrhythmic MVP (AMVP) form remains incompletely defined and uncertain

Resolving the Conundrum of Functional Mitral Regurgitation in Heart Failure with reduced Ejection Fraction.

Background: Appraisal of Functional-Mitral-Regurgitation (FMR) in Heart-failure with reduced Ejection-fraction (HFrEF) is challenging because risks of excessmortality remain uncertain and guidelines diverge . Objective: To define excess-mortality linked to FMR quantified in routine-practice. Methods: HFrEF (ejection-fraction (EF)<50%) stage B-C diagnosed 2003-2011, with routine-practice FMR quantitation (FMR-cohort, n=6381) was analyzed for excessmortality thresholds/rates within-cohort and vs. general-population and compared to degenerative-mitral-regurgitation simultaneous cohort (DMR-cohort, n=2416). Results: In FMR-cohort (age 70±11years, EF 36±10%, effective-regurgitant-orifice- EROA 0.09±0.13cm2), EROA distribution was skewed towards low-values (≥0.40cm2 in only 8% vs. 38% for DMR-cohort, p<0.0001). One-year mortality was high (15.6%), increasing steeply from 13.3% without FMR to 28.5% with EROA≥0.30 cm2(adjusted-Odds-Ratio1.57 [1.19-2.97], p=0.001). Long-term, 3538 FMR-cohort patients died with excess-mortality threshold ~0.10cm2 (vs.~0.20cm2 in DMR-cohort), with 0.10cm2 EROA-increments independently associated with considerable mortalityincrement (adjusted-hazard-ratio 1.11[1.08-1.15],p<0.0001) and with no detectable interaction. Compared to the general-population, FMR excess-mortality increased exponentially with higher EROA (risk-ratio point-estimates 2.8, 3.8 and 5.1 at EROA 0.20, 0.30 and 0.40cm2), much steeper vs. DMR-cohort (p<0.0001). In nested models, individualized EROA was strongest FMR survival-marker and a new expanded FMRgrading scale, based on 0.10 cm2 EROA increments, provided incremental power over current AHA-ACC/ESC guidelines (all P<0.03). Conclusion: In HFrEF, FMR is skewed towards smaller EROA. Nevertheless, measured in routine practice, EROA is the strongest independent FMR determinant of survival after diagnosis. Excess-mortality, increases exponentially above the threshold of 0.10 cm2, much steeper than in DMR, for any EROA increment. An expanded ERObased stratification, superior to existing grading-schemes in determining survival, should allow guidelines harmonization

Functional Mitral Regurgitation Outcome and Grading in Heart~Failure With Reduced Ejection Fraction

This study aims to define excess-mortality linked to functional mitral regurgitation (FMR) quantified in routine-practice

Functional tricuspid regurgitation of degenerative mitral valve disease: a crucial determinant of survival

Aims To assess functional tricuspid regurgitation (FTR) determinants, consequences, and independent impact on outcome in degenerative mitral regurgitation (DMR).Methods and results All patients diagnosed with isolated DMR 2003-2011, with structurally normal tricuspid leaflets, prospective FTR grading and systolic pulmonary artery pressure (sPAP) estimation by Doppler echocardiography at diagnosis were identified and long-term outcome analysed. The 5083 DMR eligible patients [6316years, 47% female, ejection fraction (EF) 637%, and sPAP 35 +/- 13mmHg] presented with FTR graded trivial in 45%, mild in 37%, moderate in 15%, and severe in 3%. While pulmonary hypertension (PHTN-sPAP >= 50mmHg) was the most powerful FTR severity determinant, other strong FTR determinants were older age, female sex, lower left ventricle EF, DMR, and particularly atrial fibrillation (AFib) (all P <= 0.002). Functional tricuspid regurgitation moderate/severe was independently linked to more severe clinical presentation, more oedema, lower stroke volume, and impaired renal function (P <= 0.01). Survival (95% confidence interval) throughout follow-up [70% (69-72%) at 10 years] was strongly associated with FTR severity [82% (80-84%) for trivial, 69% (66-71%) for mild, 51% (47-57%) for moderate, and 26% (19-35%) for severe, P<0.0001]. Excess mortality persisted after comprehensive adjustment [adjusted hazard ratio 1.40 (1.18-1.67) for moderate FTR and 2.10 (1.63-2.70) for severe FTR, P <= 0.01]. Excess mortality persisted adjusting for sPAP/right ventricular function (P<0.0001), by matching [adjusted hazard ratios 2.08 (1.50-2.89), P<0.0001] and vs. expected survival [risk ratio 1.79 (1.48-2.16), P<0.0001]. Within 5-year of diagnosis valve surgery was performed in 73% (70-75%) and 15% (13-17%) of severe and moderate DMR and in only 26% (19-34%) and 6% (4-8%) of severe and moderate FTR. Valvular surgery improved outcome without alleviating completely higher mortality associated with FTR (P<0.0001).Conclusion In this large DMR cohort, FTR was frequent and causally, not only linked to PHTN but also to other factors, particularly AFib. Higher FTR severity is associated at diagnosis with more severe clinical presentation. Long term, FTR is independently of all confounders, associated with considerably worse mortality. Functional tricuspid regurgitation moderate and even severe is profoundly undertreated. Thus careful assessment, consideration for tricuspid surgery, and testing of new transcatheter therapy is warranted

The Mitral Annular Disjunction of Mitral~Valve Prolapse

The aim of this study was to assess in patients with mitral valve prolapse (MVP) mitral annular disjunction (MAD) prevalence, phenotypic characteristics, and long-term outcomes (clinical arrhythmic events and excess mortality)

Comment les lasers ultra-courts aident à créer des reliefs hiérarchiques guidant efficacement les cellules sur des motifs nanostructurés

International audienceUltra-short laser texturing allows us to produce various surface reliefs on both nano- and micro-scales as complex hierarchical patterns. This kind of surface treatment has also advantaged in the reduction of thermal effects, of debris, and, particularly, in the minimization of surface contamination. Particularly, surface micro-patterns with additional nano-reliefs, or so-called “hierarchical reliefs” can be quite easily produced considerably alternating not only surface roughness and wettability but allowing additional opportunities to better guide the behavior of different objects ranging from nanoparticles and viruses to larger droplets and/or living microorganisms. Previously, a clear connection between cell behavior and wetting properties on laser-structured patterns has been revealed. However, the optimum laser treatment is still under discussion. In fact, laser interactions affect not only surface relief and morphology but also composition, phase state, etc. One of the known challenges is also the fact that surface properties can be unstable and evolve with time. They can be also strongly affected by additional heating, sterilization, ultra-sound or cold plasma treatment. The reasons for these changes are not yet well understood. For this, femtosecond laser irradiation of titanium-based surfaces is used. As a result, multi-scale textures are produced with high precision. Additionally, computer simulations were also performed to examine surface chemistry and particle and small droplet behavior on such surfaces. Then, wetting properties are analyzed. Finally, the capacities to capture and guide human stem cell cultures (HSC) were evaluated. Several patterns with different sizes and motifs have been examined. In general, the results confirm that wettability maps can help predict cellular behavior. The obtained results have numerous applications in bioengineering, cellular tests, the treatment of dental implants, and various prosthesis.La texturation laser ultra-courte nous permet de produire divers reliefs de surface à la fois à l'échelle nano et micro sous forme de motifs hiérarchiques complexes. Ce type de traitement de surface présente également des avantages dans la réduction des effets thermiques, des débris et, en particulier, dans la minimisation de la contamination de surface. En particulier, des micro-motifs de surface avec des nano-reliefs supplémentaires, ou soi-disant «reliefs hiérarchiques», peuvent être assez facilement produits en alternant considérablement non seulement la rugosité de surface et la mouillabilité, mais permettant des opportunités supplémentaires pour mieux guider le comportement de différents objets allant des nanoparticules aux virus. à des gouttelettes plus grosses et/ou à des micro-organismes vivants. Auparavant, un lien clair entre le comportement des cellules et les propriétés de mouillage sur les motifs structurés au laser a été révélé. Cependant, le traitement au laser optimal est encore en discussion. En fait, les interactions laser affectent non seulement le relief et la morphologie de la surface, mais aussi sa composition, son état de phase, etc. L'un des défis connus est également le fait que les propriétés de surface peuvent être instables et évoluer avec le temps. Ils peuvent également être fortement affectés par un chauffage supplémentaire, une stérilisation, un traitement aux ultrasons ou au plasma froid. Les raisons de ces changements ne sont pas encore bien comprises. Pour cela, une irradiation laser femtoseconde de surfaces à base de titane est utilisée. En conséquence, des textures multi-échelles sont produites avec une grande précision. De plus, des simulations informatiques ont également été effectuées pour examiner la chimie de surface et le comportement des particules et des petites gouttelettes sur ces surfaces. Ensuite, les propriétés de mouillage sont analysées. Enfin, les capacités de capture et de guidage des cultures de cellules souches humaines (CSH) ont été évaluées. Plusieurs modèles avec des tailles et des motifs différents ont été examinés. En général, les résultats confirment que les cartes de mouillabilité peuvent aider à prédire le comportement cellulaire. Les résultats obtenus ont de nombreuses applications dans la bio-ingénierie, les tests cellulaires, le traitement des implants dentaires et diverses prothèses