57. Aortic valve replacement with sutureless valve and mitral valve repair in patient with infected aortic homograft

The approach of implanting aortic sutureless valve inside the calcific homograft is suitable in redo surgery especially if associated with mitral valve surgery. Aortic valve replacement in patients who have undergone previous aortic root replacement with an aortic homograft remains a technical challenge because of homograft degeneration and the need for a redo Bentall operation. We report a case of redo aortic valve replacement (valve in valve) with a sutureless valve and mitral valve repair by miniband annuloplasty in a female patient aged 64years old who underwent aortic valve replacement with homograft 14years ago and presented by sever aortic valve regurge and sever mitral valve regurge because of infective endocarditis. This technique allows rapid aortic valve replacement in a heavily calcified aortic root. It also avoids aortic valve size affection after mitral valve repair by ordinary methods especially in patients with small aortic annulus. This technique is particularly suitable in redo procedures for homograft degeneration, it avoids performing a redo Bentall operation with its known problems as well as to avoid patient prosthesis mismatch

2. Minimally invasive mitral valve surgery why do you take the risks?

During recent years, minimally invasive mitral valve surgery (MIMVS) become the preferred method of mitral valve repair and replacement in many institutions worldwide with excellent results, in spite of there is no clear difinition of minimally invasive surgery and we do not have efficient studies about the risks of MIMVS comparing to conventional mitral valve surgery. Many studies are needed to clarify the need for either conventional or minimally invasive mitral valve surgery instead of personal preference. The patient’s demographic profile, intraoperative data and postoperative outcomes of patients undergoing minimally invasive mitral valve surgery were retrospectively collected from our database from May 2011 to April 2014. We will present early and mid-term outcomes of patients undergoing minimally invasive mitral valve surgery in our institution. Seventy consecutive patients (45 male and 25 female), age 35±12 years, underwent MIMVS surgery. Mean preoperative New York Heart Association function class was 2.6±0.7. Mean ejection fraction was 50±8. Cardiopulmonary bypass was instituted through femoral cannulation (28 of 70, 40%), or direct aortic cannulation (42 of 70, 25%). Aortic cross-clamp used in (66 of 70, 94.2%). Without aortic cross-clamp in (4 of 70, 5.7%), mitral valve repair has been done in (52 of 70, 74.2%), mitral valve replacement (18 of 70, 25.7%). Concomitant procedures included AF ablation (24 of 70, 34.2%), and tricuspid valve repair (33 of 70, 47.1%). No mortality recorded, residual mitral regurge was found in (6 of 70, 8.5%) during 1 year follow up. Cardiopulmonary bypass, and “skin to skin” surgery were 95±35 and 250±74min, respectively. 4 patients (5.7%) underwent reexploration for bleeding and (57 of 70, 81.4%) did not receive any blood transfusions. Six patients (8.5%) sustained face oedema. Mean length of hospital stay was 7±3.8days. 18 patients (25.7%) did not feel any interest regarding cosmotic advantage over conventional surgery. Minimally invasive mitral valve surgery is an excellent alternative to conventional mitral valve surgery in most cases however comparing to conventional mitral surgery it shows long bypass time, long cross clamp time, difficult reexploration for bleeding and multiple body incisions

Dust-Acoustic Solitary Waves in Magnetized Dusty Plasma with Dust Opposite Polarity

The nonlinear propagation of small but finite amplitude dust-acoustic solitary waves (DAWs) in magnetized collision less dusty plasma has been investigated. The fluid model is a four component magnetized dusty plasma, consisting of positive and negative dust species, isothermal electrons and ions in the presence of an external magnetic field. A reductive perturbation method was employed to obtain the Zakharov Kuznetsov (ZK) equation for the first-order potential. The effects of the presence of positively charged dust fluid, the external magnetic field, and the obliqueness are obtained. The results of the present investigation may be applicable to some plasma environments, such as cometary tails, upper mesosphere and Jupiter\u27s magnetosphere

Influence of pravastatin chitosan nanoparticles on erythrocytes cholesterol and redox homeostasis: An in vitro study

AbstractThe objective of this study was to develop and characterize chitosan nanoparticles (CSNPs) to increase efficacy of pravastatin (PR) on erythrocytes redox status. CSNPs and PR loaded CSNPs (PRCSNPs) were prepared by ionic gelation method. The particle size, zeta potential, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) were used to investigate physicochemical characters of the prepared nanoparticles. The present results revealed that CSNPs and PRCSNPs have nanosize about 90nm with spherical shape, positive zeta potential and prolonged PR release. Moreover, DSC and FTIR indicated no chemical interactions between PR and CS. In vitro studies revealed that, erythrocyte uptake of PR from PRCSNPs was higher than free PR solution. Incubation of erythrocytes in high cholesterol plasma, hypercholesterolemia (HC), increases membrane cholesterol, erythrocyte hemolysis, oxidized glutathione (GSH), protein carbonyl (PCC), and malondialdeyhe (MDA). However, HC significantly decreases PR uptake by erythrocytes, superoxide dismutase (SOD), glutathione peroxidase (GPx) catalase (CAT) activities, reduced GSH and nitrite levels compared to control. By contrast, treatment of HC with PR plus CS as free drug or nanostructure formula keeps the measured parameters at values near that of control. The effect of CSNPs and PRCSNPs on redox status of erythrocytes was more prominent than free drugs. In conclusion, PRCSNPs are promising drug carrier to deliver PR into erythrocytes, moreover, PRCSNPs possess promising characteristics with high biological safety for treatment of HC induced disruption of redox homeostasis

1.6 μm emission based on linear loss control in a Er:Yb doped double-clad fiber laser

Based on the control of the linear losses of the cavity, we demonstrate the possibility to achieve filterless laser emission above 1.6 μm, from a C-band double-clad Er:Yb doped fiber amplifier. The concept is validated in both continuous wave and mode-locked regimes, using a figure-of-eight geometry. A unidirectional ring cavity is also tested in the continuous regime. Spectral properties of laser emissions are characterized as a function of the intracavity linear losses

Secondary lithium cells for space applications

It is concluded that secondary lithium batteries are suitable for planetary missions requiring high specific energy, long active shelf life, and limited cycle life. Titanium disulfide cathode material meet all the requirements for rechargeable lithium cell, including high intrinsic reversibility and realizable specific energy. Secondary lithium technology is still evolving, although low capacity cells have been demonstrated and greater than 700 cycle life was achieved. Work is in progress to improve the cycle life and safety of the electrolytes, alternate lithium anode, and the separators

Diagnostic et prise en charge de l’hyperparathyroïdie primaire

Objectif : L’hyperparathyroïdie primaire (hPTP) est définie par la production excessive et inappropriée de parathormone (PTh). Les formes asymptomatiques et modérées sont devenues de plus en plus fréquentes. Le but de ce travail est d’étudier les caractéristiques cliniques et paracliniques de l’hPTP, de préciser les indications thérapeutiques et de les discuter en comparant nos résultats avec ceux de la littérature.Matériel et méthodes: Il s’agit d’une étude rétrospective à propos de 86 patients colligés entre Janvier 2005 et Décembre 2010. Tous les patients ont bénéficié d’un examen ORL et d’un bilan biologique comportant une calcémie et un dosage de la PTh. Le bilan radiologique comportait une échographie cervicale, une scintigraphie au MIBI et/ou une IRM cervicale.Tous les patients ont été opérés sous anesthésie générale et ont eu une cervicotomie par approche classique. La surveillance a été clinique et biologique avec un recul moyen de 16 mois (4-36 mois).Résultats : La calcémie était élevée chez 77 patients (89,5%) et la PTh chez tous les patients. Une échographie cervicale a été réalisée chez 79 patients et a montré une image en faveur d’un adénome parathyroïdien chez 37 d’entre eux (46,8%). La scintigraphie au MIBI, pratiquée chez 46 patients, a montré une hyperfixation dans 31 cas (67,4%). L’IRM aété pratiquée chez 5 patients et a révélé un adénome dans 3 cas.L’exploration chirurgicale avec examen extemporané a révélé un adénome unique chez 65 patients deux adénomes chez 12 patients, et une hypertrophie des 4 PTh chez 9 autres. Une exérèse des adénomes a été ainsi réalisée chez 77 patients et une parathyroïdectomie subtotale dans 9 cas. en post-opératoire, 12 patients (14%) ont présenté une hypocalcémietransitoire. Aucune hypocalcémie définitive ni paralysie récurrentielle n’ont été notées. L’examen anatomopathologique définitif a révélé un adénome unique, un adénome double, une hyperplasie et PTh normale respectivement chez 58, 3, 24 et 1 patients. L’évolution à long terme a été marquée par l’amélioration clinique et biologique chez 81 patients  (94,2%). Une non-amélioration clinique et biologique a été notée chez 5 patients. Ils ont été réopérés et ont eu une parathyroïdectomie subtotale. L’anatomopathologie confirmait l’hyperplasie dans tous les cas.Conclusion : Le traitement de l’hPTP symptomatique est chirurgical. L’approche classique a fait preuve de son efficacité. Les progrès récents des explorations préopératoires et le dosage peropératoire de la PTh ont rendu possible une approche mini-invasive. Des controverses persistent quant à la prise en charge de l’hPTP asymptomatique dont l’indicationthérapeutique doit être bien étudiée.Mots-clés : hyperparathyroïdie primaire, adénome, glande parathyroïde, parathormone, scintigraphie, parathyroïdectomi

Closed-loop optimization of fast-charging protocols for batteries with machine learning.

Simultaneously optimizing many design parameters in time-consuming experiments causes bottlenecks in a broad range of scientific and engineering disciplines1,2. One such example is process and control optimization for lithium-ion batteries during materials selection, cell manufacturing and operation. A typical objective is to maximize battery lifetime; however, conducting even a single experiment to evaluate lifetime can take months to years3-5. Furthermore, both large parameter spaces and high sampling variability3,6,7 necessitate a large number of experiments. Hence, the key challenge is to reduce both the number and the duration of the experiments required. Here we develop and demonstrate a machine learning methodology  to efficiently optimize a parameter space specifying the current and voltage profiles of six-step, ten-minute fast-charging protocols for maximizing battery cycle life, which can alleviate range anxiety for electric-vehicle users8,9. We combine two key elements to reduce the optimization cost: an early-prediction model5, which reduces the time per experiment by predicting the final cycle life using data from the first few cycles, and a Bayesian optimization algorithm10,11, which reduces the number of experiments by balancing exploration and exploitation to efficiently probe the parameter space of charging protocols. Using this methodology, we rapidly identify high-cycle-life charging protocols among 224 candidates in 16 days (compared with over 500 days using exhaustive search without early prediction), and subsequently validate the accuracy and efficiency of our optimization approach. Our closed-loop methodology automatically incorporates feedback from past experiments to inform future decisions and can be generalized to other applications in battery design and, more broadly, other scientific domains that involve time-intensive experiments and multi-dimensional design spaces

Effect of Gut Microbiota Biotransformation on Dietary Tannins and Human Health Implications

Tannins represent a heterogeneous group of high-molecular-weight polyphenols that are ubiquitous among plant families, especially in cereals, as well as in many fruits and vegetables. Hydrolysable and condensed tannins, in addition to phlorotannins from marine algae, are the main classes of these bioactive compounds. Despite their low bioavailability, tannins have many beneficial pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, anticancer, and cardioprotective effects. Microbiota-mediated hydrolysis of tannins produces highly bioaccessible metabolites, which have been extensively studied and account for most of the health effects attributed to tannins. This review article summarises the effect of the human microbiota on the metabolism of different tannin groups and the expected health benefits that may be induced by such mutual interactions. Microbial metabolism of tannins yields highly bioaccessible microbial metabolites that account for most of the systemic effects of tannins. This article also uses explainable artificial intelligence to define the molecular signatures of gut-biotransformed tannin metabolites that are correlated with chemical and biological activity. An understanding of microbiota–tannin interactions, tannin metabolism-related phenotypes (metabotypes) and chemical tannin-metabolites motifs is of great importance for harnessing the biological effects of tannins for drug discovery and other health benefits