Quelle est l'influence de l'utilisation d'anesthésie locorégionale en phase de latence, sur la prise en charge de cette phase, les issues obstétricales et le vécu des femmes ?: travail de Bachelor

Contexte : La douleur demeure une question prépondérante en obstétrique. L’anesthésie locorégionale (ALR) est le moyen antalgique le plus utilisé, mais non dénué d’impacts. La phase de latence est peu étudiée et peu considérée en pratique. L’innocuité de l’utilisation d’ALR en phase de latence reste à prouver. Objectif : Le but de cette revue de littérature est de mettre en évidence l’influence de l’utilisation d’ALR en phase de latence, sur la prise en charge de cette phase, les issues obstétricales et le vécu des femmes. Méthode : Une revue systématique de la littérature scientifique a été élaborée à partir de cinq études sélectionnées, dont une méta-analyse, dans les bases de données de la littérature scientifique actuelle (CINHAL, Cochrane Library, MEDLINE, MIDIRS). Résultats : La pose d’ALR en phase de latence n’augmenterait pas les conséquences inhérentes à l’ALR en général (durée de la 2eme phase du travail, utilisation d’ocytocine, survenue d’hypotension, d’état fébrile et de présentation dystocique, taux de césarienne et d’instrumentation) ; mais favoriserait la satisfaction maternelle. Cependant, il existe des facteurs prédictifs d’une demande précoce d’ALR et également prédictifs d’une césarienne (poids maternel augmenté, nulliparité/pauciparité, stimulation, provocation, rupture spontanée et prématurée des membranes [RSM et RPM1] et petit poids foetal). Les sages-femmes mettent en place des stratégies de prise en charge spécifiques au début de travail. Durant cette période, les femmes présenteraient un meilleur sentiment de contrôle ainsi qu’un niveau d’anxiété plus bas. Le lien entre l’anxiété et la demande d’antalgie n’a pas été démontré. Toutefois, l’anxiété est significativement liée à la douleur. De surcroit, une réévaluation, de la courbe de dilatation élaborée par Friedman, montre des différences notables ; remettant en question nos définitions et prises en charge actuelles. Conclusion : Notre revue de la littérature, par son faible niveau de preuves scientifiques, ne nous permet pas de généraliser les résultats à la pratique. L’ALR peut être une réponse à la douleur des femmes algiques en phase de latence. Cependant, d’autres facteurs influencent cette douleur et il convient de s’en soucier afin d’offrir une prise en charge optimale. Il paraît primordial de réadapter la courbe de progression du travail et nos définitions dans le soucis de maintenir la physiologie

Accelerated Cardiac Diffusion Tensor Imaging Using Joint Low-Rank and Sparsity Constraints

Objective: The purpose of this manuscript is to accelerate cardiac diffusion tensor imaging (CDTI) by integrating low-rankness and compressed sensing. Methods: Diffusion-weighted images exhibit both transform sparsity and low-rankness. These properties can jointly be exploited to accelerate CDTI, especially when a phase map is applied to correct for the phase inconsistency across diffusion directions, thereby enhancing low-rankness. The proposed method is evaluated both ex vivo and in vivo, and is compared to methods using either a low-rank or sparsity constraint alone. Results: Compared to using a low-rank or sparsity constraint alone, the proposed method preserves more accurate helix angle features, the transmural continuum across the myocardium wall, and mean diffusivity at higher acceleration, while yielding significantly lower bias and higher intraclass correlation coefficient. Conclusion: Low-rankness and compressed sensing together facilitate acceleration for both ex vivo and in vivo CDTI, improving reconstruction accuracy compared to employing either constraint alone. Significance: Compared to previous methods for accelerating CDTI, the proposed method has the potential to reach higher acceleration while preserving myofiber architecture features which may allow more spatial coverage, higher spatial resolution and shorter temporal footprint in the future.Comment: 11 pages, 16 figures, published on IEEE Transactions on Biomedical Engineerin

Détermination et différenciation du sexe chez l'algue brune Ectocarpus

Genetic sex determination is usually controlled by sex chromosomes carrying a non-recombining sex-determining region (SDR). Despite the common origin of sex (meiosis) in Eukaryotes, the evolution of sex chromosomes has evolved repeatedly and independently. Our knowledge in sex chromosomes comes mainly from the analysis of diploid systems (XY and ZW sex chromosomes) in animals and land plants. However the recent genome sequencing of the brown alga Ectocarpus, not only opens up the possibility of studying sex chromosomes in a phylogenetic distant group but also of analysing a haploid sex chromosome system (UV sex chromosomes). Indeed in Ectocarpus sex is expressed during the haploid phase of the life cycle, where U and V sex chromosomes are restricted to female and male, respectively. The Ectocarpus sex chromosomes have some unusual evolutionary features such as the size of the non-recombining region, which is surprisingly small for a 70 million year old system. Also the evolutionary aspect of sexual dimorphism was studied by analyzing male and female transcriptomes and by identifying several subtle sexual dimorphic traits. Parthenogenetic capacity is a sexual dimorphic trait in some populations of Ectocarpus. The genetic link between parthenogenesis and sex was analysed and a locus that controls parthenogenetic was located to the Ectocarpus sex chromosome, in the recombining pseudoautosomal region. Fitness analysis strongly suggested that the parthenogenetic locus is a sexual antagonistic locusLe déterminisme génétique du sexe nécessite souvent l’évolution d’une région non-recombinante (NR) formant ainsi paire de chromosomes sexuels. Bien que la reproduction sexuée ait une origine commune à tous les eucaryotes, l’évolution des chromosomes sexuels s’est quant à elle effectuée de manière répétée et indépendante. Les chromosomes du sexe ont été particulièrement étudiés dans les systèmes diploïdes (chromosomes sexuels XY et ZW) des plantes et animaux. Le récent séquençage du génome d’Ectocarpus, modèle d’étude des algues brunes, donne non seulement une chance unique d’analyser les chromosomes sexuels dans un groupe phylogénétiquement distant des opisthocontes et de la lignée verte ; mais il donne aussi l’opportunité d’examiner un système haploïde de chromosomes sexuels (système UV). Chez Ectocarpus l’expression du sexe a lieu pendant la phase haploïde du cycle de vie, avec les chromosomes U et V, respectivement spécifiques aux femelles et aux mâles. L’analyse des chromosomes sexuels chez Ectocarpus a montré que la taille de la région NR est restée modeste pour un système vieux de plus de 70 millions d’années. Une analyse des dimorphismes sexuels a été effectuée ainsi que l’étude comparative des transcriptomes mâle et femelle d’Ectocarpus. Le développement parthénogénétique est, dans certaines populations d’Ectocarpus, un dimorphisme sexuel. Le lien génétique entre parthénogenèse et sexe a été analysé et suggère qu’un locus contrôlant la parthénogenèse est localisé au niveau de la partie recombinante du chromosome sexuel d’Ectocarpus. De plus, une analyse de fitness indique que le locus de la parthénogenèse est soumis à une sélection antagoniste entre les deux sexes

Controllable Degradable Plasma Electrolytic Oxidation Coated Mg Alloy for Biomedical Application

A controllable degradable coating on Mg alloy based on plasma electrolytic oxidation (PEO) process is reported for the first time. The reported results show that introduction of silica nanoparticles into PEO electrolytes leads to their reactive incorporation in coatings and thus influencing the degradation behavior. Dissolution of amorphous phases facilitates chemical reaction with components of simulated body fluid, resulting in self-healing effect via redeposition of insoluble conversion products. The dynamic balance between dissolution of the original coating and reconstruction of corrosion layer is mainly determined by the phase composition of the coating as well as the surrounding corrosive medium

A design approach to a risk review for fuel cell-based distributed cogeneration systems

A risk review of a fuel cell-based distributed co-generation (FC-Based DCG) system was conducted to identify and quantify the major technological system risks in a worst-case scenario. A risk review entails both a risk assessment and a risk analysis of a designed system, and it is part of risk engineering. Thorough literature reviews and expert interviews were conducted in the field of fuel cells. A thorough literature review of the risk engineering field was also conducted. A procedure for a risk review of the FC-Based DCG System was developed. The representative system design was identified by the current DCG design technology. The risk assessment was carried out, identifying the system components and potential failure modes and consequences. Then, using probabilities of failure for the various system components, the risk associated with a particular system design was determined. A Monte Carlo simulation on the total system reliability was used to evaluate the potential for system failure at a time of 1 hour, 5 hours, 10 hours, 50 hours, 100 hours and 500 hours of continuous operation. The original system was found to be acceptable at the initial times, but after 100 hours was predicted to fail. The components which consistently contribute significantly to the overall system risk are the membrane electrode assembly (MEA) and the nickel-metal foam flow fields. A revised system was analyzed with the reliability of the MEA and the Ni-foam set to 100%. After the revision, the components which contributed significantly to the system risk were the pumps. Simulations were run for several alternative systems to provide feedback on risk management suggestions. The risk engineering process developed with the design approach for this research is applicable to any system and it accommodates the use of many different risk engineering tools

Traumatic Anterior Shoulder Dislocation With Concomitant Pectoralis Rupture and Bankart Lesion

Traumatic anterior shoulder dislocation is frequently associated with injury to the static soft tissue stabilizers of the glenohumeral joint, with the most common injury being an anterior inferior labral avulsion (Bankart lesion) in 73% of patients after a first time dislocation1. Bony injury can also occur from a single episode of instability. Glenoid rim fractures occur in 5.4%-11% of patients. Greater tuberosity fractures occur in 12%-15% in primary anterior shoulder dislocations. Hill-Sachs lesions occur in 38%-90% of primary anterior shoulder dislocations. Less commonly there can be vascular and nerve injury. Additionally, in patients over the age of 40, rotator cuff tears can occur with anterior shoulder dislocation. Pectoralis major tendon rupture commonly occurs in 20- to 40-year-old males secondary to a rapid eccentric contraction. Of 365 identified pectoralis injuries, 83% were due to indirect trauma, 48% of those occurring in weight-training activities. To our knowledge, this is the first report of a pectoralis major tendon rupture and a Bankart lesion with both lesions treated surgically, and only the second report in the literature of this combined pathology resulting from traumatic injury. In this report, a 20-year-old male patient dislocated his shoulder during an incline bench press causing pectoralis major rupture, Hill-Sachs defect, and an acute Bankart lesion. Only the pectoralis major tendon was repaired in this case. In a retrospective study looking at pectoralis major tendon rupture in the military, 53% of tears occurred during bench pressing. There have been few cases described where pec rupture occurred by another mechanism

Mg-based materials diminish tumor spreading and cancer metastases

Cancer metastases are the most common causes of cancer-related deaths. The formation of secondary tumors at different sites in the human body can impair multiple organ function and dramatically decrease the survival of the patients. In this stage, it is difficulty to treat tumor growth and spreading due to arising therapy resistances. Therefore, it is important to prevent cancer metastases and to increase subsequent cancer therapy success. Cancer metastases are conventionally treated with radiation or chemotherapy. However, these treatments elicit lots of side effects, wherefore novel local treatment approaches are currently discussed. Recent studies already showed anticancer activity of specially designed degradable magnesium (Mg) alloys by reducing the cancer cell proliferation. In this work, we investigated the impact of these Mg-based materials on different steps of the metastatic cascade including cancer cell migration, invasion, and cancer-induced angiogenesis. Both, Mg and Mg-6Ag reduced cell migration and invasion of osteosarcoma cells in coculture with fibroblasts. Furthermore, the Mgbased materials used in this study diminished the cancer-induced angiogenesis. Endothelial cells incubated with conditioned media obtained from these Mg and Mg-6Ag showed a reduced cell layer permeability, a reduced proliferation and inhibited cell migration. The tube formation as a last step of angiogenesis was stimulated with the presence of Mg under normoxia and diminished under hypoxia

Influence of the Microstructure and Silver Content on Degradation, Cytocompatibility, and Antibacterial Properties of Magnesium-Silver Alloys In Vitro

Implantation is a frequent procedure in orthopedic surgery, particularly in the aging population. However, it possesses the risk of infection and biofilm formation at the surgical site. This can cause unnecessary suffering to patients and burden on the healthcare system. Pure Mg, as a promising metal for biodegradable orthopedic implants, exhibits some antibacterial effects due to the alkaline pH produced during degradation. However, this antibacterial effect may not be sufficient in a dynamic environment, for example, the human body. The aim of this study was to increase the antibacterial properties under harsh and dynamic conditions by alloying silver metal with pure Mg as much as possible. Meanwhile, the Mg-Ag alloys should not show obvious cytotoxicity to human primary osteoblasts. Therefore, we studied the influence of the microstructure and the silver content on the degradation behavior, cytocompatibility, and antibacterial properties of Mg-Ag alloys in vitro. The results indicated that a higher silver content can increase the degradation rate of Mg-Ag alloys. However, the degradation rate could be reduced by eliminating the precipitates in the Mg-Ag alloys via T4 treatment. By controlling the microstructure and increasing the silver content, Mg-Ag alloys obtained good antibacterial properties in harsh and dynamic conditions but had almost equivalent cytocompatibility to human primary osteoblasts as pure Mg