Peroral endoscopic myotomy: a two-center retrospective study of practice and adverse events.

Background and study aims: Peroral endoscopic myotomy (POEM) is the preferred technique for the treatment of esophageal motility disorders and is less invasive than surgery. This study was performed to compare two university centers in the practice of POEM, in terms of efficacy and adverse events, for the treatment of esophageal motility disorder. Patients and methods: Retrospective comparative study of patients undergoing a POEM between September 2020 and December 2022 from the University Hospital of Liège (Belgium) and Besançon (France). The clinical success was defined by an Eckardt score ≤ 3 after the procedure. Results: Fifty-five patients were included. In both centers, 87,3% of the patients had achalasia (mostly type II), and 12,7% had another esophageal motility disorder. The use of antibiotic prophylaxis was systematic in Liège center but not in Besançon center (100% and 9.1% respectively). The mean value of the post-operative Eckardt score was 1.55± 2.48 in both center with 93.2% of patients with a score ≤ 3 (92% in Besançon and 94.74% in Liège). The rate of adverse event was generally low. There were two minor adverse events more frequent in Liège, clinical capnomediastinum and pain at day one, but they were managed with conservative treatment. Only 7.3% of the total patients had an infectious phenomenon that did not correlate with the use of antibiotic prophylaxis. Conclusion: The post-operative Eckardt score and the adverse event rate were comparable between the university centers. This study confirmed that POEM is a safe and effective technique. It also showed that using an antibiotic prophylaxis does not influence the development of infectious adverse events.

Laser temperature programmed desorption: A flexible technique to study ion-surface interaction.

Understanding the physical-chemical processes ruling the interaction of particles (atoms, molecules, and ions) with surfaces is fundamental in several research fields, such as heterogeneous catalysis, astrochemistry, and nuclear fusion. In particular, the interaction of hydrogen isotopes with plasma facing materials represents a high-priority research task in the fusion community. Such studies are essential to ensure the successful operation of experimental fusion reactors, such as the tokamak ITER. In this work, we present a surface science apparatus developed to study ion-surface interaction in fusion relevant systems. It combines laser-based techniques with contaminant-free ion/molecular beams, mass spectrometry, and surface science tools such as low-energy electron diffraction and Auger electron spectroscopy. It allows to cover a wide range of sample temperatures, from 130 to 2300 K, by changing the heating rate of samples from 0.1 to 135 K/s and maintaining the linearity of the heating ramps, a powerful feature to gain insight on adsorption, absorption, and desorption mechanisms. Experimental calibration and performance are presented in detail. Moreover, to provide a factual overview of the experimental capabilities, we focus on two different applications: the protocol used to clean a W(110) single crystal sample and the development of laser temperature programmed desorption to study helium retention in tungsten.

High-energy acceleration phenomena in extreme-radiation-plasma interactions.

We simulate, using a particle-in-cell code, the chain of acceleration processes at work during the Compton-based interaction of a dilute electron-ion plasma with an extreme-intensity, incoherent γ-ray flux with a photon density several orders of magnitude above the particle density. The plasma electrons are initially accelerated in the radiative flux direction through Compton scattering. In turn, the charge-separation field from the induced current drives forward the plasma ions to near-relativistic speed and accelerates backwards the nonscattered electrons to energies easily exceeding those of the driving photons. The dynamics of those energized electrons is determined by the interplay of electrostatic acceleration, bulk plasma motion, inverse Compton scattering and deflections off the mobile magnetic fluctuations generated by a Weibel-type instability. The latter Fermi-like effect notably gives rise to a forward-directed suprathermal electron tail. We provide simple analytical descriptions for most of those phenomena and examine numerically their sensitivity to the parameters of the problem.

Mechanical behavior and corrosion resistance of sol-gel derived 45S5 bioactive glass coating on Ti6Al4V synthesized by electrophoretic deposition.

The purpose of this work is the synthesis and the characterization of sol-gel derived 45S5 bioactive glass coatings deposited onto Ti6Al4V alloy substrates. This coating aims the improvement of the biocompatibility of metallic implants for use in dentistry and orthopedy. The 45S5 bioactive glass powder was synthetized by the sol-gel process and the coatings were produced by the electrophoretic deposition technique (EPD). A grinding protocol was developed to reduce the particle size distribution of the sol-gel powder in order to obtain a stable suspension needed for the electrophoretic deposition. The particle size distribution of the sol-gel powder was determined using Dynamic Light Scattering (DLS). Different characterization techniques including X-ray diffraction (XRD), Scanning electron microscopy (SEM) associated to X-ray microanalysis (EDXS), were used to investigate the microstructure and the morphology of the coatings before and after an optimized thermal treatment. Homogeneous 45S5 bioactive glass coatings were obtained with no observable defects. However these coatings are functional if they present good mechanical properties. Thus, a mechanical study using nano-indentation and micro-scratch testing was carried out. The obtained results showed that well adherent and cohesive coatings were obtained. The Young's modulus and the hardness are improved with the thermal treatment. Indeed, they increased from 11 ± 0.54 GPa and 100 ± 4.34 MPa respectively to 28 ± 1.34 GPa and 300 ± 14.21 MPa. The corrosion resistance of the coatings was also studied. The electrochemical were carried using a Potentiostat-Galvanostat PGZ301 in 3.5% NaCl solution at 37 °C. It was observed that the 45S5 sol-gel derived bioactive glass coatings allowed the enhancement of corrosion resistance of the implant.

Time-resolved structural dynamics of the out-of-equilibrium charge density wave phase transition in GdTe3.

We use ultrafast electron diffraction to study the out-of-equilibrium dynamics of the charge density wave (CDW) phase transition in GdTe3, a quasi-two-dimensional compound displaying a unidirectional CDW state. Experiments were conducted at different incident fluences and different initial sample temperatures below Tc. We find that following photo-excitation, the system undergoes a non-thermal ultrafast phase transition that occurs in out-of-equilibrium conditions. The intrinsic crystal temperature was estimated at each time delay from the atomic thermal motion, which affects each Bragg peak intensity via the Debye Waller factor. We find that the crystal temperature stabilizes with a 6 ps timescale in a quasi-equilibrium state at temperature Tq.e.. We then relate the recovery time of the CDW and its correlation lengths as a function of Tq.e.. The charge density wave is suppressed in less than a picosecond while its recovery time increases linearly with incident fluence and initial temperature. Our results highlight that the dynamics is strongly determined by the initial sample temperature. In addition, the transient CDW phase recently observed along the transverse direction in LaTe3 and CeTe3 is not observed in GdTe3.

Symmetric and asymmetric shocked gas jets for laser-plasma experiments.

Shocks in supersonic flows offer both high density and sharp density gradients that are used, for instance, for gradient injection in laser-plasma accelerators. We report on a parametric study of oblique shocks created by inserting a straight axisymmetric section at the end of a supersonic "de Laval" nozzle. The effect of different parameters, such as the throat diameter and straight section length on the shock position and density, is studied through computational fluid dynamics (CFD) simulations. Experimental characterizations of a shocked nozzle are compared to CFD simulations and found to be in good agreement. We then introduce a newly designed asymmetric shocked gas jet, where the straight section is only present on one lateral side of the nozzle, thus providing a gas profile well adapted for density transition injection. In this case, full-3D fluid simulations and experimental measurements are compared and show excellent agreement.

[Flap harvest training on a new ultrarealistic simulation model: In-training operator feedback about a pulsating reperfused and reventilated cadaver Simlife®]. / Prélèvement des lambeaux sur sujet anatomique et nouveau modèle de simulation ultra-réaliste : retour d'expérience d'un opérateur en formation sur corps reperfusé pulsatile et reventilé Simlife®.

INTRODUCTION: The anatomical subject is still a key element to learn complex procedures in plastic surgery. We present here the evaluation of an in-training operator on a SIMLIFE® model, hyper realistic model consisting in human bodies donated to science equipped with pulsating recirculation and reventilation device. MATERIAL AND METHODS: From February 2019 to October 2019, 8 forearm flaps with radial proximal pedicle were harvested by the learner on a SIMLIFE® model. Conditions were as close as possible to the operating room : asepsy, sterile draping, assistant and instrumentation including electrocoagulation. RESULTS: The procedure was decomposed in 13 distinct steps. Mean total surgery time was 90,5±11,62minutes. There was only one case of arterial pedicle lesion resulting in major blood leak. Bleeding was measured by fake blood loss from the SIMLIFE® console. Mean intraoperatoy bleeding was 171±108 milliliters. We review pros and cons of this new technology particulary suited for complex plastic and reconstructive surgery training. CONCLUSION: Using SIMLIFE® technology we have a new mean to train for complex procedures in plastic and reconstructive surgery. This new technology could be applied to numerous other surgical procedures. Broader applications are still limited by cost and cadaver use legislation.

[Training simulation during the announcement of fetal malformation discovered on screening ultrasound: Results of a pilot study]. / Formation par simulation à l'annonce d'une malformation fœtale découverte en échographie de dépistage : résultats d'une étude pilote.

OBJECTIVES: Breaking bad news (BBN) to a pregnant woman with fetal abnormalities (FA) on ultrasound (US) examination is a challenge. Announcement technique influences patient reaction. Physicians receive little training in BBN. The simulation and using a BBN protocol as the English SPIKES protocol which guides the announcement consultation according to 6 steps (Setting Up, Perception, Invitation, Knowledge, Emotions and Empathy, Strategy and Summary) can be used for this teaching. The objective was to assess feasibility simulation scenarii of BBN for FA discovered during US and to evaluate the usefulness of SPIKES protocol in this situation. METHODS: Two scenarios have been created combining US simulator (US Mentor, Symbionix®) with simulated patient (SP). Scenarii objectives were to diagnose FA and break it to SP. Checklist derived from SPIKES was fulfilled by two investigators thanks to video recording, the SP and every participant (residents, physicians, fetal medicine specialists [FMS]). Participants filled out survey about the usefulness of this exercise too. RESULTS: Nine physicians (3 residents, 4 physicians, 2 FMS) produced 18 scenarii. Seventy-eight percent of physicians thought simulation was like real situation of BBN during US examination. Majority of participant (88%) found that this simulation training could help them to increase their ability to BBN and that it can be used to teach residents (89%) or physicians (100%). FMS had better SPIKES checklist than physicians (P<0,05). CONCLUSION: Simulation scenario of BBN for FA discovered during US is feasible by combining US simulator and SP. SPIKES protocol can be useful but a validated checklist should be created.

SimLife model: introducing a new teaching device in endocrine surgery simulation.

To evaluate the validity and reliability of an innovative training model for endocrine surgical procedures. A simulator training model for endocrine procedures (SimLife) was developed at an academic center. The model consisted of a realistic operating environment with a coherent simulated patient dynamized by pulsatile vascularization with simulated blood warmed to 37 °C, and ventilation. Training sessions were designed for adrenal and thyroid surgery, as well as neck dissection. The primary outcome of interest was to evaluate learners' performance and satisfaction. Learners' performance was evaluated based on a scoring scale that followed the Downing method for the assessment of competency. While learners' satisfaction was evaluated using a Likert scale of 1 to 10 on four items (ease of learning, anatomic correspondence of landmarks, realism, and overall satisfaction). Participants were engaged in 32 training sessions. These included 24 adrenalectomies (conventional and laparoscopic both transabdominal and posterior), and 4 thyroid lobectomies with concomitant functional lateral compartment neck dissection. competency scores were procedure-specific addressing specific core components of a given procedure. Learners' performance scored above average in all procedures evaluated. Satisfaction scores for the specified four items ranged between 8.43 (SD 0.87) and 8.89 (SD 0.96). No major events were reported for the adrenalectomies, while only one jugular vein injury occurred during neck dissection. SimLife is a hyper-realistic training model that allows for satisfactory acquisition of skills and the evaluation of performance progression. It has the potential to become a cornerstone in specialized surgical training.

Clinical, functional and genetic characterization of 16 patients suffering from chronic granulomatous disease variants - identification of 11 novel mutations in CYBB.

Chronic granulomatous disease (CGD) is a rare inherited disorder in which phagocytes lack nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity. The most common form is the X-linked CGD (X91-CGD), caused by mutations in the CYBB gene. Clinical, functional and genetic characterizations of 16 CGD cases of male patients and their relatives were performed. We classified them as suffering from different variants of CGD (X910 , X91- or X91+ ), according to NADPH oxidase 2 (NOX2) expression and NADPH oxidase activity in neutrophils. Eleven mutations were novel (nine X910 -CGD and two X91- -CGD). One X910 -CGD was due to a new and extremely rare double missense mutation Thr208Arg-Thr503Ile. We investigated the pathological impact of each single mutation using stable transfection of each mutated cDNA in the NOX2 knock-out PLB-985 cell line. Both mutations leading to X91- -CGD were also novel; one deletion, c.-67delT, was localized in the promoter region of CYBB; the second c.253-1879A>G mutation activates a splicing donor site, which unveils a cryptic acceptor site leading to the inclusion of a 124-nucleotide pseudo-exon between exons 3 and 4 and responsible for the partial loss of NOX2 expression. Both X91- -CGD mutations were characterized by a low cytochrome b558 expression and a faint NADPH oxidase activity. The functional impact of new missense mutations is discussed in the context of a new three-dimensional model of the dehydrogenase domain of NOX2. Our study demonstrates that low NADPH oxidase activity found in both X91- -CGD patients correlates with mild clinical forms of CGD, whereas X910 -CGD and X91+ -CGD cases remain the most clinically severe forms.

Sensibilización central en la artrosis / Central sensitization in osteoarthritis

El dolor de los pacientes con artrosis es un problema sociosanitario de primera magnitud y es el responsable de la importante limitación funcional y pérdida de calidad de vida en esta enfermedad.A pesar de haberse producido avances importantes en el conocimiento de los mecanismos fisiopatológicos del dolor, son muchos los interrogantes del dolor artrósico que todavía quedan por contestar.Uno de los aspectos menos estudiados del dolor crónico en la artrosis es el fenómeno de sensibilización central.La resonancia magnética nuclear funcional se ha mostrado como una técnica útil para el abordaje de este fenómeno.Diferentes estudios realizados a pacientes afectos de artrosis con distintos grados de sensibilización ponen de manifiesto que la incidencia de este fenómeno es elevada, que los pacientes sensibilizados y no sensibilizados muestran patrones diferentes en cuanto a la magnitud de la repuesta cerebral al dolor y que los patrones de conectividad difieren de una enfermedad a otra.Finalmente, en los pacientes candidatos a artroplastia de rodilla es importante evaluar el grado de sensibilización previo a la cirugía, puesto que son los pacientes con mayor grado de sensibilización los que presentarán evoluciones más tórpidas y mayores niveles de dolor posquirúrgico.(AU)

Pain in patients with osteoarthritis is a social and health problem of great magnitude and is responsible for the significant functional limitation and loss of quality of life in this disease.Despite the important advances made in the knowledge of the pathophysiological mechanisms of pain, many questions about arthritic pain remain unanswered.One of the least studied aspects of chronic pain in osteoarthritis is the phenomenon of central sensitization.Functional Magnetic Resonance Imaging has shown to be a useful technique for addressing this phenomenon.Many studies carried out in patients with osteoarthritis with different degrees of sensitization show that the incidence of this phenomenon is high, that sensitized and non-sensitized patients show different patterns in terms of the magnitude of the cerebral response to pain and that the connectivity patterns differ from one disease to another.Finally, in patients who are candidates for knee arthroplasty, it is important to evaluate the degree of sensitization prior to surgery, since it is the patients with the highest degree of sensitization who will present more torpid evolutions and higher levels of post-surgical pain.(AU)

Bariatric Surgical Simulation: Evaluation in a Pilot Study of SimLife, a New Dynamic Simulated Body Model.

BACKGROUND: The demand for bariatric surgery is high and so is the need for training future bariatric surgeons. Bariatric surgery, as a technically demanding surgery, imposes a learning curve that may initially induce higher morbidity. In order to limit the clinical impact of this learning curve, a simulation preclinical training can be offered. The aim of the work was to assess the realism of a new cadaveric model for simulated bariatric surgery (sleeve and Roux in Y gastric bypass). AIM: A face validation study of SimLife, a new dynamic cadaveric model of simulated body for acquiring operative skills by simulation. The objectives of this study are first of all to measure the realism of this model, the satisfaction of learners, and finally the ability of this model to facilitate a learning process. METHODS: SimLife technology is based on a fresh body (frozen/thawed) given to science associated to a patented technical module, which can provide pulsatile vascularization with simulated blood heated to 37 °C and ventilation. RESULTS: Twenty-four residents and chief residents from 3 French University Digestive Surgery Departments were enrolled in this study. Based on their evaluation, the overall satisfaction of the cadaveric model was rated as 8.52, realism as 8.91, anatomic correspondence as 8.64, and the model's ability to be learning tool as 8.78. CONCLUSION: The use of the SimLife model allows proposing a very realistic surgical simulation model to realistically train and objectively evaluate the performance of young surgeons.

Development of a program for teaching practical skills in visceral and digestive surgery by simulation.

Up until 2013 in France, practical training for DES/DESC (advanced level) residents in visceral and digestive surgery was not standardized. Since 2017, the third cycle of medical studies has been restructured around three major thematic axes: academic knowledge, and technical and non-technical skills. The curriculum now includes a practical training program by means of simulation outside the operating theater, and it is structured, uniformized and standardized nationwide. Development of this training program is derived from the deliberations of a national consensus panel working under the umbrella of the French college of visceral and digestive surgery, program presenting a training guide to all future surgeons in the specialty. Four consensus conference sessions bringing together an eight-member commission have led to the drafting of a "Resident's manual for practical teaching in visceral and digestive surgery". As a reference document, the manual details in 272 pages the objectives (phase I), the learning resources for each skill (phase II) and, lastly, the means of evaluation for the cornerstone phases as well as the in-depth phases of an advanced degree (DES) in visceral and digestive surgery. As a complement to the manual, we have conducted a review of the structuring and implementation of the program as of November 2017 on a nationwide scale; the conclusions of the review are detailed at the end of this article.

SimLife® technology in surgical training - a dynamic simulation model.

In initial surgical formation and continuing surgical education, simulation has become a compulsory technique. Just as becoming an airplane pilot requires skills, the acquisition of technical skills is essential to becoming a surgeon. The old apprenticeship model "I see, I do, and I teach" is no longer entirely compatible with the socio-economic constraints of the operating room, demands for guaranteeing patient safety, and the compulsory reduction in resident working hours. We propose a new surgical simulation model, using cadavers donated to science that are rendered dynamic with pulsatile vascularization and ventilation. Such models are available for simulation of both open surgery and laparoscopy. Surgery on a human body donated to science makes it possible to accurately reproduce the hand gestures characteristic of surgical procedures. Learning in an appropriate and realistic simulation context increases the level of skills acquired by residents and reduces stress and anxiety when they come to perform real procedures.

Outcome of medical therapy for keratomalacia in dogs.

OBJECTIVES: To evaluate the clinical and visual outcomes following intensive medical therapy for keratomalacia in dogs. MATERIALS AND METHODS: Medical records were screened to identify dogs with corneal ulcers and keratomalacia. All patients were given the same topical treatment protocol with frequent administrations of tobramycin in combination with equine serum. Surgical treatment during the first 15 days of follow-up was considered as medical treatment failure. RESULTS: We report on 57 ulcers with keratomalacia from 53 dogs. Medical treatment was successful in 31 of 57 ulcers with a median healing time of 5 days (range 2 to 15 days). At 60 days after epithelialisation, 14/15 medically-treated eyes were visual. In one case, corneal perforation was observed 1 month after healing and required surgical stabilisation. CLINICAL SIGNIFICANCE: Intensive medical therapy has the potential to achieve healing of some ulcers with keratomalacia. Surgical stabilisation in response to progression of stromal loss was required in less than half of the cases.

[Male to female sex reassignment surgery with a new surgical simulation device using a human perfused cadaver SIMLIFE®: New paradigm in transsexual surgery education ?] / Aïdoïopoïèse sur modèle cadavérique humain revascularisé pulsatile et ventilé SIMLIFE® : cas isolé ou futur changement de paradigme en chirurgie de réassignation génitale ?

INTRODUCTION: In 2015, we reported our experience with the learning curve in genital reassignment surgery and highlighted a four-step learning concept. CLINICAL CASE: In this article, we present our first vaginoplasty performed on a humanoid model SIMLIFE®, a human body associated with a pulsating circulation device and a ventilation device. RESULTS: The surgical technique included 14 steps. The total surgical time was 182minutes. There was no intraoperative complication, and there was no damage to the urethra or rectum. The intraoperative bleeding measured by the loss of operative fluid was 280mL. We discuss the advantages of this technology perfectly adapted to transsexual surgery. CONCLUSION: We demonstrated the feasibility of vaginoplasty performed on a humanoid model SIMLIFE® and highlighted improvement of the surgical skills with this model. This technology could find many other surgical applications. However, it faces cost constraints and legislation on corpses.

Numerical modelling of the suspended particulate matter dynamics in a regulated river network.

Understanding and predicting the propagation, deposition and resuspension of suspended particulate matter (SPM) in river networks is important for managing water resources, ecological habitat, pollution, navigation, hydropower generation, reservoir sedimentation, etc. Observational data are scarce and costly, and there is little feedback on the efficiency of numerical simulation tools for compensating the lack of data on a river scale of several hundreds of kilometers. This paper aims at exploring the use of a one-dimensional (1-D) hydrodynamical model for understanding the source and fate of SPM during complex events. The numerical model was applied to the May-June 2008 flood in the Lower Rhône River, France. This event was a combination of floods of the Isère (including dam flushing operations in the Lower Isère River) and Durance tributaries over a two-week period. The simulation code was used to model the SPM fluxes at a high spatial and temporal resolution using a multi-class approach. Approximately half of the 4.9 Mt of SPM measured at the outlet at Beaucaire were found to come from the Isère River and the other half from the Durance River, whereas previous studies estimated that most of the SPM flux at the outlet came from the Durance River. The amount of SPM trapped within the river network, mainly behind the first hydropower structure downstream of the Isère confluence, was estimated to be 3.7 Mt due to the deposition of the coarsest particles. Such a model proved to be able to compute the interaction of various grain size classes with dams and other structures. In turn, the quality of the results of SPM fluxes and deposition is highly sensitive to particle parameters, especially grain size distribution, and to the operational rules of reservoirs.

Contribution of minimally invasive bone augmentation to primary stabilization of the osteosynthesis of Schatzker type II tibial plateau fractures: Balloon vs bone tamp.

BACKGROUND: Schatzker type II tibial plateau fractures necessitate the least invasive treatment possible. Arthroscopic reduction by bone tamp followed by osteosynthesis is the current gold standard for this type of tibial plateau fracture. The objective of this study was to compare this technique to anterior approach tuberoplasty with balloon reduction. The comparison criteria were residual articular step off, metaphyseal cavity volume formed during reduction, and mechanical strength to separation and to depression displacement. METHODS: Fractures were created on 12 human cadaveric tibiae and reduced by a minimally invasive approach in six specimens by a balloon, and by bone tamp in the six others. Articular step off and metaphyseal-epiphyseal cavity volume were measured by TDM. Mechanical tests were performed up to assembly failure to characterize structural strength. Secondary displacements, fracture depression displacement and separation were measured by optical methods. FINDINGS: There was no significant difference in step off measurement after balloon reduction or bone tamp (0.29 cm vs 0.37 cm; p = 0.06). The cavity volume formed by balloon reduction was significantly smaller than the volume created by bone tamp reduction (0.45 cm3 vs 5.12 cm; p = 0.002). The compressive load required for assembly failure was significantly greater in the balloon group than in the bone tamp group (1210.17 N vs 624.50 N; p = 0.015). INTERPRETATION: There exists a correlation between load to failure of the assembly frame and the metaphyseal volume required for bone fracture reduction. The minimally invasive balloon technique has fewer negative effects on the osseous stock, thereby enabling better primary structural strength of the fracture.