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Resume Introduction Une nouvelle generation d’incubateurs a chambres individuelles de faible volume a ete developpee afin d’ameliorer la stabilite des conditions de culture et ainsi reduire le stress environnemental sur l’embryon. Ce type d’incubateur dit sec fonctionne en hygrometrie ambiante sans systeme d’humidification de l’air en vue de diminuer la proliferation bacterienne et de permettre l’utilisation d’un systeme de monitorage video type time-lapse. Cependant, leur utilisation pourrait generer un risque d’evaporation plus importante des milieux de culture embryonnaire, en comparaison a l’utilisation de chambres d’incubation a atmosphere humidifiee. Cette etude a pour objectif principal de determiner l’impact du type d’incubateur utilise sur l’osmolalite des milieux de culture embryonnaire dans differentes conditions operatoires. Materiels et methodes Des micro-gouttes de 50 μL de milieu de culture embryonnaire ont ete deposees dans des boites de Petri de 60 mm de diametre et recouvertes par 7 ou 8 mL d’huile minerale sous une hotte a flux laminaire. Deux series de boites ont ete reparties de facon aleatoire et homogene soit dans un incubateur sec, soit dans un incubateur standard a atmosphere humidifiee. Les micro-gouttes de chaque boite ont ete prelevees a j0, j1, j2, j3 et j5 pour effectuer une mesure de l’osmolalite en triplicate a l’aide d’un osmometre cryoscopique. Les valeurs moyennes pour chaque type d’incubateur ont ete comparees respectivement a j0, j1, j2, j3 et j5, sur series appariees (j1–5 vs. j0 d’un meme incubateur) ou non appariees (j1–5 incubateur sec vs. j1–5 incubateur a atmosphere humidifiee) a l’aide des tests statistiques appropries, avec un seuil de significativite p Resultats L’osmolalite des micro-gouttes placees dans l’incubateur sec variait significativement a partir du 3e jour de culture, quel que soit le niveau d’huile ajoute. En effet, en utilisant respectivement 7 ou 8 mL d’huile, l’osmolalite a j3 et j5 des echantillons preleves dans l’incubateur sec etait significativement plus elevee lorsque comparee a celle de l’incubateur a atmosphere humidifiee (j3/7 mL : 273 ± 2,1 vs. 268 ± 1,0 mOsm/kg, p = 0,02 ; j3/8 mL : 282 ± 8,0 vs. 270 ± 0,7 mOsm/kg, p = 0,04 ; j5/7 mL : 283 ± 1,5 vs. 270 ± 3,6 mOsm/kg, p = 0,004 ; j5/8 mL : 287 ± 5,6 vs. 268 ± 2,3 mOsm/kg ; p = 0,005). Concernant l’analyse sur series appariees dans l’incubateur sec et compare a la valeur observee a j0 (265 ± 1,9 mOsm/kg), l’osmolalite etait significativement plus elevee a j5 (283 ± 1,5 mOsm/kg ; p = 0,003) en ajoutant 7 mL d’huile ou a j3 (282 ± 8,0 mOsm/kg ; p = 0,016) et j5 (287 ± 5,6 mOsm/kg ; p = 0,009), lorsque 8 mL d’huile minerale recouvraient les boites de culture. A l’inverse, aucune difference significative de l’osmolalite n’etait observee de j0 a j5 dans l’incubateur a atmosphere humidifiee. Conclusion Il existe une evaporation des milieux de culture embryonnaire dans les incubateurs secs a hygrometrie atmospherique ambiante dans nos conditions standards. Cette evaporation n’etait pas reduite par l’ajout d’1 mL d’huile minerale supplementaire. L’impact de ces variations d’osmolalite sur le developpement embryonnaire reste a definir, meme si les valeurs d’osmolalite des milieux de culture observees a j5 dans les incubateurs secs restent physiologiques.

STUDY QUESTION Does unilateral oophorectomy modify the relationship between serum anti-Müllerian hormone (AMH) levels and antral follicle count (AFC)? SUMMARY ANSWER No altered ‘per-ovary’ and ‘per-follicle’ AMH production and antral follicle distribution was evident in unilaterally oophorectomized women compared to matched controls. WHAT IS KNOWN ALREADY The age of menopause onset is relatively unchanged in patients having undergone unilateral oophorectomy. Mechanisms that occur to preserve and maintain ovarian function in this context remain to be elucidated. STUDY DESIGN, SIZE, DURATION Forty-one infertile women, with no polycystic ovary syndrome (PCOS) and no endometriosis, aged 19–42 years old, having undergone unilateral oophorectomy (One Ovary group; average time since surgery: 23.8 ± 2.2 months) were retrospectively age-matched (±1 year) with 205 infertile women having two intact ovaries and similar clinical features (Control group). PARTICIPANTS/MATERIALS, SETTING, METHODS Serum AMH levels, 3–4 mm AFC, 5–12 mm AFC, and total AFC (3–12 mm) were assessed on cycle Day 3 in both groups. Hormonal and ultrasonographic measurements obtained from patients in the Control group (i.e. having two ovaries) were divided by two to be compared with measurements obtained from patients of the One Ovary group (i.e. having one single remaining ovary). To estimate per-follicle AMH production, we calculated the ratio between serum AMH levels over 3–4 mm AFC, 5–12 mm AFC, and total AFC (3–12 mm), and the strength of the correlation between serum AMH levels and total AFC. The main outcome measure was to assess Day 3 AMH/Day 3 AFC ratio and hormonal-follicular correlation. MAIN RESULTS AND THE ROLE OF CHANCE As expected, before correction, mean serum AMH levels (1.46 ± 0.2 vs 2.77 ± 0.1 ng/ml, P LIMITATIONS/REASONS FOR CAUTION The retrospective character of the analysis might lead to potential bias. WIDER IMPLICATIONS OF THE FINDINGS The present investigation did not provide evidence of altered ‘per-ovary’ and ‘per-follicle’ AMH production and antral follicle distribution in unilaterally oophorectomized women compared to matched controls. Further studies are warranted to support the hypothesis that follicle-sparing mechanisms are clearly at stake in remaining ovaries after unilateral oophorectomy to explain their long-lasting function and timely menopausal onset. STUDY FUNDING/COMPETING INTEREST(S) The authors have no funding or competing interests to declare. TRIAL REGISTRATION NUMBER N/A.

Study question Do fresh and vitrified/warmed oocytes have the same developmental potential in low prognosis patients defined by POSEIDON criteria? Summary answer Embryos derived from vitrified/warmed oocytes show lower competence for embryo development when compared to those obtained from fresh oocytes in low prognosis patients. What is known already The strategy of oocyte accumulation has been proposed for the management of low-prognosis patients with the aim to increase the number of oocytes available for fertilization and further the number of embryos. The effect of oocyte vitrification/warming on the embryo developmental potential has mainly been studied in oocyte donation programs. Investigations on sibling-oocyte failed to show difference in the morphological embryo development, but the evaluation stopped after 2-3 days of embryo culture. In addition, morphokinetic evaluation revealed delayed development of embryos derived from vitrified oocytes, from the first cleavage to the time of blastulation. Study design, size, duration Single-center sibling-oocyte retrospective monocentric study including low-prognosis patients, defined by POSEIDON criteria, who had undergone an accumulation of oocyte strategy for managing their infertility, between November 2013 and January 2021. Only patients presenting fresh and vitrified/warmed oocytes at the time of insemination were analyzed for the sibling-oocyte comparison. Main study outcomes were fertilization, cleavage, blastulation rates, day-2 and day-5 embryo quality, and the rate of embryos available for transfer/cryopreservation. Participants/materials, setting, methods Forty-five patients were included, with a mean age of 34.8 ± 3.4 years. Oocyte vitrification/warming was performed using the Cryotop method. Top-quality and good-quality embryos were defined at day-2 respectively as 4 and 3-5 adequate-sized blastomeres, without multinucleation and containing Main results and the role of chance A total of 656 oocytes were inseminated, 225 fresh and 431 vitrified/warmed oocytes. The oocyte survival rate after warming was 82%, 95%CI [76-87%]. There was no difference between fresh and vitrified/warmed oocytes groups regarding the degeneration rate following ICSI (5.0% vs 4.8% respectively, p = 0.95), the fertilization rate (74.6% vs 71.4% respectively, p = 0.42) or the cleavage rate on day-2 (98.3% vs 95.4% respectively, p = 0.15). However, the embryo development was significantly different from day 2, with higher day 2 top-quality and good-quality embryos rates in the fresh oocytes group when compared to the vitrified/warmed oocytes group (top-quality: 38.3% vs 24.8% respectively, p = 0.01; good-quality 58.0% vs 45.2% respectively, p = 0.02). The same results were observed on blastocysts when extended culture was decided, with a higher blastulation rate in the fresh oocyte group (56.7% vs 31.7% respectively, p Limitations, reasons for caution The retrospective nature of the study, on a limited number of limited number of patients represents an inherent limitation. Embryo assessment was subjective, the evaluator knowing the oocyte’s source group. The impact of the morphological alterations observed in embryos derived from vitrified/warmed oocytes need to be confirmed with clinical outcomes. Wider implications of the findings The majority of studies comparing fresh and vitrified/warmed oocytes were performed in egg-donation programs. This study focuses on low-prognosis patients, who reflect perhaps more the patients who consult in ART centers. Further prospective studies are needed to confirm our findings. Trial registration number Not applicable

Study question Is IDA-score a useful tool to accurately classify embryos? Summary answer IDA-score is a reliable tool to categorize embryos into top/good/poor morphological quality. However, hierarchical classification of embryos between IDA-score and embryologists was significantly different. What is known already Since Preimplantation Genetic Test for aneuploidy is not authorized in France, morphological scoring by embryologists is the only way to select blastocysts for transfer at Day-5. However, morphological scoring cannot perfectly predict implantation likelihood. Promising recent artificial intelligence techniques might improve both hierarchical classification and clinical outcomes. For instance, IDA-score combined with Embryoscope (Vitrolife®) has been suggested as a way to objectively compare a given embryo to a large embryo dataset and generate a score that predicts the likelihood of implantation using a deep-learning approach. So far, no external independent analysis compares the accuracy of this score with human performance. Study design, size, duration This retrospective-monocentric-study was performed in our reproductive medicine unit from September to December 2021. A total of 167 embryos from 58 couples undergoing ICSI were monitored on a daily-basis and scored at Day-5 by IDA-score and morphological scoring by a panel of senior-embryologists blinded from results of IDA-score. In all, 52 single embryos selected by embryologists were transferred during fresh or frozen cycles. Clinical pregnancy rates were defined by presence of fetal heartbeat on ultrasound. Participants/materials, setting, methods Each embryo was monitored and scored at Day-5 by both morphological scoring and IDA-score. Only the best 3 embryos were ranked and compared. Morphological score was based on Gardner-and-Schoolcraft grading system and classified according to morphological score as top-quality (≥B4BB), good-quality (≥B3BB) and poor-quality ( Main results and the role of chance The mean age of women was 33.96±0.66 years. Morphological scoring led to 68.8% (115/167) top quality embryos, 80.2% (134/167) good quality embryos and 19.8% (33/167) poor quality embryos. Mean IDA-scores of embryos were respectively 9.06 ± 0.48 for top-quality, 8.72 ± 0.62 for good-quality and 7.12 ± 1.34 for poor-quality blastocysts (global p Limitations, reasons for caution These results should be interpreted with caution due to the retrospective design of the study and small effectives. Wider implications of the findings We present preliminary results of an external independent series to confirm the efficiency of IDA-score in daily routine practice. Since IDA-score is not consistent with human scoring concerning hierarchical classification, its performance has to be further assessed to clearly establish the input of artificial intelligence in IVF laboratory practice. Trial registration number not applicable

The main objective of this study is to valorize the flowers of poppy (Papaver rhoeas L.) plant belonging to the family of Papaveraceae, by studying the following parameters resulting from two types of methanolic extraction methods (maceration, soxhlet): polyphenols content, antioxidant power and antibacterial effects. The total phenolic contents (TPC) determined by Folin-Ciocalteu colorimetric assays in both maceration and soxhlet extracts are rich in total phenolic concentrations with the values of 95.4 ± 2.42 and 165.4 ± 3.84 mg GAE/g, respectively, while the flavonoid fractions represent the minor proportion with 8.67 ± 0.024 mgQE/g and 21.7 ± 2.05 mg QE/g, respectively. The antioxidant activity was evaluated using free radical scavenging method diphenyl picryl-hydrazyl (DPPH), the results obtained from both extracts are interesting than that of ascorbic acid used as a standard (IC50 = 0.13879 mg/ml). The highest and important antioxidant power recorded was attributed to soxhlet extract (IC50 = 3.81 mg/ml) compared to that of maceration extract (IC50 = 4.97 mg/ml). The antibacterial activities were conducted in agar medium against six types of bacterial species, half of which are Gram- (Escherichia coli, Klebsiella pneumonia, Salmonella spp) and the others are Gram+ (Staphylococcus aureus, Listeria monocytogenes, and Enterobacter feacalis). The potential antibacterial effect was revealed by soxhlet extract against Enterobacter feacalis, with MIC value of 0.11 mg/ml. All extracts present an interesting bacteriostatic effect on the studied strains and could be used as a natural and alternative to synthetic antibiotic drugs. Finally, the soxhlet extract has proven to be the best procedure for studying the Papaver rhoeas flowers, in terms of polyphenol recovery, antioxidant effect, and antimicrobial activities. Those properties might be explored, as a natural antibacterial with health benefits, and a source of natural antioxidants in food.

Human embryo culture under 2–8% O2 is recommended by ESHRE revised guidelines for good practices in IVF labs. Nevertheless, notably due to the higher costs of embryo culture under hypoxia, some laboratories perform embryo culture under atmospheric O2 tension (around 20%). Furthermore, recent meta-analyses concluded with low evidence to a superiority of hypoxia on IVF/ICSI outcomes. Interestingly, a study on mice embryos suggested that oxidative stress (OS) might only have an adverse impact on embryos at cleavage stage. Hence, we aimed to demonstrate for the first time in human embryos that OS has a negative impact only at cleavage stage and that sequential culture conditions (5% O2 from Day 0 to Day 2/3, then «conventional» conditions at 20% O2 until blastocyst stage) might be a valuable option for human embryo culture. 773 IVF/ICSI cycles were included in this randomized clinical trial from January 2016 to April 2018. At Day 0 (D0), patients were randomized using a 1:2 allocation ratio between group A (20% O2; n = 265) and group B (5% O2; n = 508). Extended culture (EC) was performed when ≥ 5 Day 2-good-quality-embryos were available (n = 88 in group A (20% O2)). In subgroup B, 195 EC cycles were randomized again at Day 2 (using 1:1 ratio) into groups B’ (5% O2 until Day 6 (n = 101)) or C (switch to 20% O2 from Day 2 to Day 6 (n = 94). Fertilization rate, cleavage-stage quality Day 2-top-quality-embryo (D2-TQE), blastocyst quality (Day 5-top-quality-blastocyst (D5-TQB) and implantation rate (IR) were compared between groups A and B (= cleavage-stage analysis), or A(20% O2), B’(5% O2) and C(5%-to-20% O2). Overall, characteristics were similar between groups A and B. Significantly higher rates of early-cleaved embryos, top-quality and good-quality embryos on Day 2 were obtained in group B compared to group A (P P 2 from Day 0 to Day 6 (group A) resulted in significantly lower Day 5-TQB number and rates (P P = 0.45). At Day 6, TQB numbers and rates were also significantly higher in groups B’ and C compared to group A (P P

Zusammenfassung Hintergrund Künstliche Intelligenz (KI) wird zunehmend in der bildgebenden Mammdiagnostik eingesetzt. Fragestellung Was sind die wesentlichen Anwendungsgebiete und bereits verfügbaren KI-gestützten Systeme auf dem Gebiet der senologischen Radiologie? Material und Methode Zusammenfassung, übersichtliche Darstellung sowie Diskussion relevanter Daten aus Grundlagenarbeiten und Herstellerinformationen. Ergebnisse KI-gestützte Befundsysteme sind bereits seit fast 25 Jahren in der Mammadiagnostik im Einsatz, werden jedoch in den USA weitaus häufiger angewandt als in Europa. Initiale CAD-Systeme (computergestützte Diagnostik) zeichneten sich durch eine limitierte diagnostische Aussagekraft mit überproportionalen Raten falsch-positiver Befunde aus. Seit 2012 kommen Deep–Learning-Algorithmen zum Einsatz und erweitern die Einsatzmöglichkeiten der KI. Schlussfolgerung Derzeit gibt es keinen Algorithmus, der – nachweislich validiert – die Doppelbefundung durch zertifizierte Mammaradiologen übertrifft. In der mittelbaren Zukunft ist jedoch die Übernahme von Aufgaben durch KI absehbar: So kann die Vorselektion abnormer Studien die Arbeitslast gerade in der Früherkennung substanziell verringern. Auch die Erfassung von komplexen radiopathogenomischen Zusammenhängen und besonders ihre Translation in die klinische Praxis ist ohne KI kaum denkbar.

Benchtop incubators with small individual chambers have been developed in order to improve the stability of embryo culture conditions reducing the environmental stress during the embryo development. These new dry incubators were designed without any air humidification system in order to prevent bacterial proliferation and to enable the use of time-lapse system. However, an elevated evaporation of the culture media could occur in these conditions. The main objective of the study is to analyse the impact of the used incubator type on the embryo culture media osmolality.Microdrops of 50μL of culture media were placed in 60mm diameter culture dishes, and quickly covered with either 7 or 8mL of mineral oil in an IVF workstation with laminar airflow. Two series of culture dishes have been randomly placed either in a humidified incubator or in a dry benchtop incubator. The microdrops of each culture dishes were sampled at D0, D1, D2, D3, and D5 respectively to measure the osmolality in triplicate using a cryoscopic osmometer. The mean values of osmolality in each incubator have been compared respectively on D0, D1, D2, D3 and D5 with appropriate statistical tests, and considered statistically significant when P0.05.The osmolality of the microdrops placed in the dry benchtop incubator differed significantly after the third day of culture, regardless of the level of mineral oil in the culture dishes. Indeed, using Petri dishes covered respectively with 7 or 8mL of mineral oil, osmolality values of samples from the dry incubator were significantly higher than those from the humidified one, at D3 and D5 (D3/7mL: 273±2.1 vs. 268±1.0mOsm/kg; P=0.02; D3/8mL: 282±8.0 vs. 270±0.7mOsm/kg; P=0.04) and D5 (D5/7mL: 283±1.5 vs. 270±3.6mOsm/kg; P=0.004; D5/8mL: 287±5.6 vs. 268±2.3mOsm/kg; P=0.005). Furthermore, the analysis on paired samples showed that the osmolality in the dry benchtop incubator at D5 using 7mL of oil (283±1.5mOsm/kg; P=0.003) and at D3 (273±2.1mOsm/kg; P=0.016) and D5 (287±5.6mOsm/kg; P=0.009) using 8mL of oil was significantly higher than that measured at D0 (265±1.9mOsm/kg).A significant increase of the embryo culture media osmolality was observed in the dry benchtop incubator with ambient hygrometry in our standard conditions. Adding 1mL of oil was not sufficient to reduce the evaporation of the media. Although maintained at a physiological level, the impact of the osmolality changes on the in vitro embryo development has to be further determined.

Digital ulcers generally arise in a context of microangiopathy-related focal ischemia. In women, connective tissue diseases are the main etiology, while in men the cause is often diffuse arterial disease, e.g. Leo-Buerger disease, or emboligenic heart disease. A paraneoplastic origin of digital necrosis due to ischemia is rarely reported. A 75-year-old man presented with cyanosis of the fingertips and toes that had begun one month earlier. The physical examination found pulp ulcers on the fingers and toes of both hands and feet. Two weeks later, necrotic damage developed distally, with no other associated symptoms. Blood tests were suggestive of Kahler disease; immunodeficiency disorders tests were negative; the cyroglobulin test was positive. Multiple-drug chemotherapy was followed by clinical improvement. Distal necrotic damage is a frequent inaugural symptom in vascular disease. If the common causal mechanisms (iatrogenic, occupational, toxic, atheromatous, emboligenic heart disease, or systemic disease) have been ruled out, it is important to search for a blood disorder or cancer as the cause of distal necrotic damage.

Introduction L’uveite est l’inflammation intraoculaire qui touche l’uvee. L’uveite granulomateuse se caracterise par des precipites de cellules inflammatoires de grande taille sur l’endothelium corneen, appeles « en graisse de mouton », des nodules inflammatoires sur le bord de la pupille (nodules de Koeppe) ou dans le stroma de l’iris (nodules de Busacca). C’est une pathologie relativement peu decrite, sa prise en charge diagnostique et therapeutique ne beneficie toujours pas de protocoles bien codife. Nous avons essaye d’en degager ses caracteristiques cliniques et therapeutiques ainsi que leur profil etiologique. Patients et methodes Il s’agit d’une etude retrospective realisee au sein de notre service colligeant 22 patients presentant une uveite granulomateuse sur une periode de 5 ans (janvier 2015–decembre 2020). Le diagnostic d’uveite granulomateuse etait base sur l’examen clinique ophtalmologique. Tous les patients ont beneficie d’une enquete etiologique comportant un interrogatoire, un examen physique complet et un bilan systematique (NFS, dosage de l’enzyme de conversion de l’angiotensine, une biopsie des glandes salivaires accessoires, une IDR a la tuberculine, recherche de Bacille de Koch dans les crachats, serologies virales(HSV,CMV),la syphilis, la toxoplasmose et la radiographie du thorax). Les modalites therapeutiques et evolutives ont ete analysees. Resultats Il s’agissait de 19 femmes et 3 hommes (sex ratio F/H = 6,33) dont l’âge moyen etait de 36,8 ± 15,2 ans (extremes de 17 a 69 ans). L’uveite granulomateuse etait revelee par une baisse de l’acuite visuelle chez 90 % des cas, une rougeur oculaire chez 81 % des cas et des douleurs oculaires chez 31 % des cas. Elle etait unilaterale chez 18 % des cas et bilaterale chez 81,8 % des cas. Il s’agissait d’une uveite anterieure dans 5 cas (22 %), d’une panuveite 5 cas (22 %), intermediaire dans 3 cas (14 %) et elle touchait le segment posterieur dans 9 cas (42 %). Elle etait severe par la presence d’un œdeme maculaire dans deux cas et d’un decollement retinien dans trois cas. L’uveite etait associee a une vascularite retinienne dans 3 cas (13,6 %). L’enquete etiologique revelait une sarcoidose dans 5 cas (22 %), une granulomatose avec polyangeite dans 3 cas (13,6 %), un syndrome de Vogt-Koyanagi-Harada dans 2 cas (9 %), une tuberculose dans 2 cas (9 %), une infection a HSV dans un cas et une maladie de Behcet dans un cas. L’enquete etiologique est en cours chez 2 cas et etait negative chez le reste des patients (soit 27 % des cas). Le traitement etait base sur une corticotherapie systemique chez 19 patients (86 %), un traitement immunosuppresseur par Cyclophosphamide avec relais par Azathioprine chez 7 patients (33 %), un traitement par anti-TNF dans 6 cas (27 %), methotrexate dans 5 cas (22 %) et un traitement antituberculeux chez 2 patients. L’evolution etait favorable dans 54,5 % des cas avec une remission chez 33 % des cas et amelioration chez 22 % des cas. Des complications etaient notees chez 27 % des malades : apparition d’une cataracte chez 4 malades avec une hypertonie associee dans un cas. Un diabete induit chez un patient et un trouble psychiatrique chez un patient. Conclusion Les uveites granulomateuses sont rarement reportees et representent un defi diagnostique et therapeutique permanent pour l’ophtalmologiste et l’interniste. La mise en jeu du pronostic visuel impose une demarche diagnostique exhaustive et une intensification therapeutique progressive.

International audience; Among the various mechanisms which occur during impact, the strain rate effect plays a significant role on the mechanical response of layered carbon fibre reinforced polymer structure. In this work, the viscoelastic behaviour of the material is studied to introduce a strain-rate dependency. To preserve numerical efficiency the generalised Maxwell model, formulated in the strain-space, is taken as a basis. The non-linear viscoelastic behaviour is introduced by coupling the generalised Maxwell model with a pre-existing intralaminar matrix continuum damage model. The fact that the Maxwell model preserves the explicit scheme of the damage model leads to an efficient material model for impact simulations. This paper proposes a complete framework to implement the strain-rate sensitive damage model in an explicit finite element code (for low-speed impact simulations). For this purpose, the procedure of parameter identification, based on DynamicMechanical Analysis, is given. Furthermore, a challenging experimental procedure on high-speed jack device with a particular attention paid to the consistency of the results is proposed to validate the developed model.

Introduction L’hematopoiese extramedullaire (HEM) est un phenomene physiologique reactionnel a une anemie chronique, frequemment observe au cours de nombreuses hemopathies. Ce processus prend naissance lors d’une dysfonction de la mœlle osseuse, quand la production de globules rouges devient insuffisante. Les pathologies hematologiques les plus souvent associees a l’HEM sont les anemies hemolytiques congenitales, les syndromes myeloproliferatifs et les syndromes myelodysplasiques. Nous presentons l’observation de deux patients qui ont developpe une hematopoiese extramedullaire de localisation paravertebrale et renale. Observation Observation 1 : patient de 36 ans, admis au service de medecine interne et onco-hematologie pour des douleurs thoraciques atypiques et dyspnee stade II de NYHA evoluant depuis trois semaines, avec un sub-ictere conjonctival, examen clinique normal. Au bilan paraclinique ; la radiographie du thorax a objective des opacites latero-tracheales bilaterales a limite externes polylobes et limites internes effaces par le mediastin et les bords du cœur, et au scanner thoracique la presence de part et d’autre du rachis dorsal des 2 masses spontanement denses rehaussees apres contraste mesurant (14,8 × 7,5 cm a gauche et 14 × 6 cm a droite). Ces 2 masses presentent un contact intime avec le poumon avec respect du lisere de separation, Il s’y associe un aspect epaissi de la trame osseuse des arcs posterieurs des 5, 6, 7, 8e cote ainsi que des corps vertebraux dorsaux avec lyse de la corticale par endroit. Sur le plan biologique, la numeration formule sanguine avait objective une legere anemie a 10 normochrome normocytaire regenerative, et au frottis sanguin la presence d’une erythroblastemie estimee a 78 % faite d’erythroblastes acidophiles avec corps de Howell–Jolly et presence d’une anisopoikylocytose des globules rouges faites d’hematies en cible et de drepanocytoses. Le bilan d’hemolyse etait positif. Nous avons realise Une electrophorese de l’hemoglobine, qui a montre un taux de l’hemoglobine F a 90 % et a la biologie moleculaire des mutations ponctuelles ont ete detectees par un sequencage de l’ADN genomique, sur les produits d’amplification des exons 1 et 2 du gene HBB, le resultat est en faveur d’une β0 thalassemie (allele β0/β0). La biopsie scanno-guidee des masses para-vertebrales n’a pas ete realisee vue le risque de saignement. Selon ces criteres cliniques, biologiques et radiologiques, nous avons etabli le diagnostic presomptif d’HEM secondaire a une β0 thalassemie majeur. Le patient est mis sous hydroxyuree avec un suivi regulier en consultation. Observation 2 : patient de 63 ans, admis pour bilan etiologique d’une splenomegalie arrivant jusqu’a l’ombilic. La numeration formule sanguine avait montre une anemie a 6,6 g/dL, normochrome normocytaire, des plaquettes a 244 000/mm3, et une hyperleucytose a 22 700/mm3, a predominance PNN avec une myelemie etagee a 15 %. Myelogramme normal, mutation V617F du gene Jak2 etait positive, biopsie osteomedullaire en cours. Pour explorer les douleurs abdominales, le patient a beneficie d’un scanner abdominal, il a montre une importante splenomegalie homogene mesuree a 28 × 14 cm, refoulant et comprimant le rein gauche vers le bas et vers l’arriere, les 2 reins sont de taille normale, mesures a droite 11,4 cm, a gauche 11,5 cm, secretent et excretent dans les delais, siege d’infiltrat tissulaire au niveau medullaire se rehaussant apres contraste. Une IRM abdominale faite en faveur d’une infiltration tissulaire medullaire des deux riens en hyposignal T2 et Fiesta, non restrictif et peu rehausse apres contraste, en rapport avec une HEM. La biopsie scanno-guidee des masses para-vertebrales n’a pas ete realisee vue le risque de saignement. Le patient est mis sous hydoxyuree en attendant le resultat de la biopsie osteomedullaire. Conclusion L’hematopoiese extramedullaire (HEM) est la consequence d’un mecanisme compensateur en reponse a une production insuffisante de cellules sanguines par la mœlle osseuse, ou a une destruction massive des erythrocytes. Le processus peut impliquer pratiquement n’importe quel organe ou tissu. Nous avons rapporte deux observations originales qui illustrent ce phenomene.

Artificial intelligence (AI) is increasingly applied in the field of breast imaging.What are the main areas where AI is applied in breast imaging and what AI and computer-aided diagnosis (CAD) systems are already available?Basic literature and vendor-supplied information are screened for relevant information, which is then pooled, structured and discussed from the perspective of breast imaging.Original CAD systems in mammography date almost 25 years back. They are much more widely applied in the United States than in Europe. The initial CAD systems exhibited limited diagnostic abilities and disproportionally high rates of false positive results. Since 2012, deep learning mechanisms have been applied and expand the application possibilities of AI.To date there is no algorithm that has beyond doubt been proven to outperform double reporting by two certified breast radiologists. AI could, however, in the foreseeable future, take over the following tasks: preselection of abnormal examinations to substantially reduce workload of the radiologists by either excluding normal findings from human review or by replacing the double reader in screening. Furthermore, the establishment of radio-patho-genomic correlations and their translation into clinical practice is hardly conceivable without AI.

Introduction Le purpura thrombopenique immunologique (PTI) est une affection autoimmune acquise caracterisee par une thrombopenie Patients et methodes Cette etude retrospective a ete conduite au service de medecine interne et d’oncohematologie entre janvier 2012 et decembre 2020, centree sur des patients âges de 16 a 29 ans et suivis pour purpura thrombopenique immunologique primaire nouvellement diagnostiques. La severite du syndrome hemorragique a ete evaluee par le score hemorragique Creteil (d’apres Khellaf et al.). L’objectif de cette etude etait de decrire les caracteristiques epidemiologiques, cliniques, therapeutiques et de suivi chez ces patients en comparaison avec celui des patients de plus de 29 ans. Resultats Quarante-deux patients ont ete inclus durant cette periode (27 % des patients suivis pour PTI) L’âge moyen au diagnostic etait de 19,9 ± 3,6 ans avec une predominance feminine (74 %). La presentation clinique initiale etait dominee par les episodes hemorragiques dans 89 % des cas. Il s’agit de 32 episodes d’hemorragies cutanees, 16 episodes de gingivorragie, 14 episodes d’epistaxis, 12 episodes d’hemorragie d’origine gynecologique, 5 episodes d’hematurie, un episode de rectorragie, une asthenie dans un cas et un caractere asymptomatique dans 5 cas. Le score hemorragique etait ≥ 8 dans 50 % des cas. Aucun facteur declenchant n’a ete retrouve dans 86 % des cas, un syndrome infectieux prealable et un etat de stress ont ete retrouves dans respectivement 10 % et 4 % des cas. Le taux moyen de plaquettes etait de 7,900 ± 6,400/mm3. Trente-huit patients (90 %) avaient un taux de plaquettes inferieur a 20,000/mm3. La thrombopenie etait isolee dans 48 % des cas. Une anemie, le plus souvent ferriprive etait associee dans 43 % des cas, une leucopenie dans 12 % des cas. Un traitement de premiere ligne a ete entrepris chez 95 % des patients (corticoides 90 % et/ou immunoglobulines intraveineuses 7 %). Le taux de reponse au traitement a 21 jours etait de 95 %. Une rechute precoce est survenue dans 10 % des cas et 15 % ont evolue vers la chronicite. Moins du tiers des patients ont justifie un traitement de deuxieme et troisieme ligne : Rituximab (9 cas), splenectomie (6 cas), Romiplostim (5 cas), Eltrombopag (3 cas), Azathioprine (2 cas), Vincristine (1 cas) et Dapsone (1 cas). Seuls 14 % des patients ont ete splenectomises, avec une reponse globale de 83 % :L’incidence de la splenectomie a diminue au profit du Rituximab, utilise dans 21 % des cas avec reponse a 21 jours a 89 % des cas mais avec une reponse durable au-dela de 6 mois dans seulement 22 % des cas. Vingt-neuf patients (72,5 % des patients symptomatiques) ont presente une poussee unique repondant au traitement de premiere ligne sans rechute ulterieure. En analyse multivariee, les saignements gynecologiques et cutaneo-muqueux etaient plus frequentes chez les patients jeunes (p = 0,016 et p = 0,038) sans difference significative du score hemorragique (p = 0,88). L’anemie et le caractere unique des poussees etaient egalement plus souvent observes chez les jeunes patients (p = 0,02 et p = 0,048). Conclusion Le PTI de « l’adolescent et jeune adulte » est similaire a celui de l’enfant et l’adulte en termes de diagnostic et de moyens therapeutiques. Les resultats de notre etude affirment que la presentation clinique est “hydride” entre le profil pediatrique et celui de l’adulte : de nombreux patients necessitent un traitement et la majorite rentrent en remission prolongee. Une attention particulaire doit etre soulignee sur la prophylaxie chez ces jeunes patients en pleine activite physique, ainsi qu’aux saignements « omis ou inapercus », principalement les menorragies abondantes. Un soutien psychologique et une prise de decision partagee permettent un meilleur controle de la maladie chez ces patients d’âge vulnerable.

International audience; The complex architecture of bone has been investigated for several decades. Some pioneer works proved an existing link between microstructure and external mechanical loading applied on bone. Due to sinuous network of canals and limitations of experimental acquisition technique, there has been little quantitative analysis of three-dimensional description of cortical network. The aim of this study is to provide an algorithmic process, using Python 3.5, in order to identify 3D geometrical characteristics of voids considered as canals. This script is based on micro-computed tomographic slices of two bone samples harvested from the humerus and femur of male cadaveric subject. Slice images are obtained from 2.94 μm isotropic resolution. This study provides a generic method of image processing which considers beam hardening artefact so as to avoid heuristic choice of global threshold value. The novelty of this work is the quantification of numerous three-dimensional canals features, such as orientation or canal length, but also connectivity features, such as opening angle, and the accurate definition of canals as voids which ranges from connectivity to possibly another intersection. The script was applied to one humeral and one femoral samples in order to analyse the difference in architecture between bearing and non-bearing cortical bones. This preliminary study reveals that the femoral specimen is more porous than the humeral one whereas the canal network is denser and more connected.

Polymers are currently used in several industrial applications such as the interior components of the vehicle. We find them for example in the design of dashboards or door panels. These materials may be subjected to different types of load like the temperature variation or high strain rates due to crash impact. It is therefore necessary to well understand and to anticipate the complex mechanical behaviour of the polymers. This paper describes the results of experimental research about the dependence between the strain rate and the temperature. The main objective is to be able to model the complete variety of the behaviour in order to predict the risk of failure under dynamic loadings. The material chosen for this study is a copolymer propylene ethylene mineral (talc) filled 15% impact modified.

Digital ulcers generally arise in a context of microangiopathy-related focal ischemia. In women, connective tissue diseases are the main etiology, while in men the cause is often diffuse arterial disease, e.g. Leo-Buerger disease, or emboligenic heart disease. A paraneoplastic origin of digital necrosis due to ischemia is rarely reported. A 75-year-old man presented with cyanosis of the fingertips and toes that had begun one month earlier. The physical examination found pulp ulcers on the fingers and toes of both hands and feet. Two weeks later, necrotic damage developed distally, with no other associated symptoms. Blood tests were suggestive of Kahler disease; immunodeficiency disorders tests were negative; the cyroglobulin test was positive. Multiple-drug chemotherapy was followed by clinical improvement. Distal necrotic damage is a frequent inaugural symptom in vascular disease. If the common causal mechanisms (iatrogenic, occupational, toxic, atheromatous, emboligenic heart disease, or systemic disease) have been ruled out, it is important to search for a blood disorder or cancer as the cause of distal necrotic damage.

IF=3.85; International audience; Needed to simulate the behaviour of industrial components through finite element analysis, a continuum damage model formulation for fabric reinforced polymers is provided. Based on the Onera Damage Microstructure Model, it considers the influence of privileged direction of intralaminar matrix damage on the stiffness. In this work, the stored strains are considered as representative of the position of the crack lips. Thus, after calculation of the stresses applied to the crack lips, a friction law has been newly implemented in order to represent the hysteresis loops during cyclic loading. Moreover, the possibility of a shear locking, very common among the textile simulations for large shearing, is introduced with its effect on the matrix damage. The present model is applied to simulate various fabric preforms (woven or non-crimp) under cyclic in-plane shear. Because of similarities of the physical phenomena which occur in each investigated materials, the present model is able to represent a realistic behaviour for every preforms investigated.

In this paper, an original and effective model of behaviour for short-fibre reinforced composites is presented. In particular, complex fibre distributions of orientation can be dealt with in a very easy way, without orientation averaging or additional homogenisation steps. The matrix material has elastoplastic damage behaviour with non-isochoric plastic flow. Ductile damage can be fully anisotropic depending on the reinforcement characteristics. The model is validated for the case of a polypropylene reinforced with short flax fibres. In addition, simulations are performed to investigate the influence of key parameters like fibre length and interfacial shear strength, as well as the impact of progressive debonding at the fibre tips.

Among currently available bio-based polymers, poly(lactic acid) (PLA) has interesting physical and mechanical properties (high tensile strength and stiffness, good processability and biodegradability) but relatively low thermal stability, low toughness and is extremely brittle, all of which can be obstacles to industrial applications. The influence of several additives is investigated in this paper, the aim being to confer mechanical properties to PLA-based compositions suitable for potential use in automotive applications. Comparisons of their mechanical properties with those of a mineral filled polypropylene, as frequently used for automotive applications, show that PLA-plasticizer-impact modifier-nanoclay quaternary compositions represent interesting bio-based alternatives.

In this paper, a behaviour model for damageable elastoplastic materials reinforced with short fibres that have complex orientations is proposed. The composite material is seen as the assembly of the matrix medium and several linear elastic fibre media. Its macroscopic behaviour is computed thanks to an additive decomposition of the state potential, with no need to implement complex methods of homogenisation. A 4th-order tensor that depends on the characteristics of each fibre medium is introduced to model the anisotropic damage of the matrix material induced by the reinforcement, as well as the progressive degradation of the fibre–matrix interface. The division of short fibres into several families means that complex distributions of orientation or random orientation can be easily modelled. The model is tested for the case of a polyamide reinforced with different contents of short-glass fibres with distributed orientations and subjected to uniaxial tensile tests in different loading directions. The comparison of the results with experimental data (extracted from the literature) demonstrates the efficiency of the model.

Introduction L’histiocytose avec lymphadenopathie massive ou maladie de Rosai-Dorfman est une pathologie benigne et rare, d’etiologie inconnue. Elle touche tous les âges avec un pic de frequence a 20 ans. Le diagnostic de certitude de la maladie repose sur l’examen histologique. Le traitement le plus utilise est la chimiotherapie faisant appel aux corticoides seuls ou associes a un agent cytotoxique. Observation Nous rapportons le cas d’une patiente âgee de 72 ans, sans antecedent pathologique, Le debut de sa symptomatologie remonte a 4 ans par l’installation d’une douleur lombaire gauche associee a une hematurie totale non caillotante, sans signes irritatifs ni obstructifs, le tout evoluant dans un contexte d’apyrexie et de conservation de l’etat generale. Le bilan biologique a objective une hyperleucocytose avec une predominance polynucleaire, un examen cytobacteriologique des urines a montre une hyperleucocyturie avec une culture negative, et une fonction renale correcte. Un uroscanner realise montre un processus tissulaire heterogene au niveau du pole superieur du rein gauche mesurant 8 cm de grand axe. Ce processus s’etend sur la region hilaire renale avec envahissement de la veine renale gauche. Le diagnostic de la maladie de Rosai de Dorfman ete retenu sur les resultats anatomopathologiques de la nephrectomie totale du rein gauche avec un immunomarquage positif l’Anticorps anti-CD68. Un bilan d’extension par un scanner cervico-thoracoabdominale a montre 2 lesions hepatiques hypodenses contigues, au niveau du segment V et VII, sans adenopathies profondes. Une corticotherapie est instauree en bolus de 1 g/j de methylprednisolone pendant trois jours, relayee par de la prednisone par voie orale. Devant la non-amelioration clinique et radiologique, la patiente a recu six cures de vimblastine a un mois d’intervalle l’evolution etait favorable, avec un recul de 2 ans. Discussion L’atteinte renale de la maladie est rare, et ne represente que 3,3 % des cas selon le registre de 1990 (14 cas/423). Il s’agissait soit d’une glomerulonephrite rapidement progressive (2 cas), soit d’une glomerulonephrite post-streptococcique (2 cas), soit d’une infiltration renale le plus souvent bilaterale (10 cas). Cette atteinte renale peut etre asymptomatique ou decouverte a l’occasion de signes de compression, de fievre ou d’insuffisance renale. C’est le cas de notre patiente chez laquelle la douleur lombaire a ete le signe revelateur de la maladie. L’abstention therapeutique est le plus souvent justifiee. Les indications therapeutiques sont reservees aux formes directement menacantes, aux formes progressives, ou devant la presence de facteurs de mauvais pronostic. C’est le cas de notre patiente ou la localisation renale est consideree comme facteur de mauvais pronostic. Conclusion L’atteinte renale au cours de la maladie de Rosai-Dorfman est rare et de mauvais pronostic, la combinaison d’arguments cliniques et histologiques permet de poser un diagnostic precoce.

Introduction L’angiœdeme bradykinique par deficit en C1 Inhibiteur acquis (AOA) est une forme rare d’angiœdeme bradykinique. Il se caracterise cliniquement par une survenue tardive apres l’âge de 40 ans, l’absence d’antecedents familiaux d’angiœdeme et une moindre frequence des crises abdominales par rapport aux angiœdemes hereditaires (AOH). Ses caracteristiques biologiques sont un dosage ponderal et une activite fonctionnelle de la proteine C1 inhibiteur (C1 Inh) abaisses ; il se distingue de l’AOH par une diminution du taux de C1q. Observation Nous rapportons le cas d’une patiente âgee de 58 ans diabetique sous ADO qui presente depuis l’âge de 36 ans des œdemes recurrents des mains et des pieds (durant 48 a 72 h, sans urticaire associee) regressant spontanement, avec des oedemes de Quincke tous les 8 mois, ne repondant pas au traitement par corticoides ni adrenaline. L’examen clinique entre les crises etait normal. Il n’y a pas d’allergie, pas d’atopie, pas d’antecedents familiaux d’angioeodeme. Hospitalisee en mois de mai 2017 dans un service de reanimation pour dyspnee laryngee compliquee par la suite par un œdeme. Apres stabilisation, la patiente est adressee dans notre service pour complement de prise en charge. Elle a rapporte comme signes systemiques une secheresse buccale, photosensibilite et des arthromyalgies. Au bilan de confirmation : C 1 inhibiteur ponderal a 38 mg/l (220–390) C1inhibiteur fonctionnel a 11 %. Le diagnostic d’angioedeme avec deficit en C1inhibiteur est pose. Mais devant l’absence d’histoire familiale et un depistage negatif chez les enfants, un angioedeme acquis est recherche. Le dosage du C1q, abaisse a 13 mg/l, a confirme l’origine acquise. La recherche d’une gammapathie monoclonale, d’un syndrome lymphoproliferatif ou d’une maladie auto-immune, pouvant etre responsables de cette symptomatologie, a ete effectuee : Les AAN etaient negatifs, bilan paraneoplasique etait negatif, et l’EPP etait sans anomalie. La patiente a ete mise sous Danazol avec 400 mg comme dose cliniquement efficace. Conclusion Le diagnostic d’angioedeme acquis avec deficit en C1inhibiteur doit etre evoque devant un âge tardif d’apparition des symptomes, generalement superieur a 40 ans (selon la litterature), et l’absence d’histoire familiale. Dans certains cas, comme presente ici, le debut des symptomes peut etre plus precoce. Que la pathologie d’angioedeme soit acquise ou hereditaire, la symptomatologie est identique.

International audience; A phenomenological finite strain non-associated elastoviscoplastic model coupled with damage is proposed in order to simulate the behaviour of a 20% mineral filled semi-crystalline polymer for a large strain rate range under several loading conditions. In the proposed model, the direct relation between the logarithmic rate of the Eulerian Hencky strain tensor (work-conjugate of the Cauchy stress) with the additively decomposition of the stretching tensor in an elastic and a viscoplastic part is used. The viscoplastic formulation is developed with the association of a pressure dependent yield surface coupled with damage to take the rate and the pressure dependency into account. In order to capture the non-isochoric deformation involving expansion under tensile loading and compaction under compression loading, a viscoplastic potential is developed. This model is implemented in a user-material subroutine in an implicit finite element code with a fully implicit viscoplastic return scheme for solid and shell elements. The particular case of shell elements is dealt with by using a second iteration loop to ensure the zero-normal-stress condition. All the material parameters are identified from experimental tests carried out at several kinds and speed loadings. Numerical responses of the proposed model are close to the experiments for several kinds and speed loadings.

This paper deals with the modelling of the behaviour of short-fibre reinforced composites. The composite is seen as an assembly of a matrix medium and of several fibre media. Each fibre medium, characterised by its own orientation of fibres and volume fraction, is considered as a one-dimensional elastic medium. The matrix material has an elastoplastic behaviour. All types of hardening laws can be considered, thanks to a valuable adaptivity of the modelling. The use of the Drucker–Prager criterion for plasticity and non-associative plasticity rules allow to deal with compressible plastic flow. Moreover, all kind of orientation of fibres, in particular random orientations and imperfect alignments, can be modelled in a simple way. The influence of the fibres’ orientation on the mechanical response of a polymer matrix composite subjected to tensile/compression tests is analysed in detail. Finally, simulated behaviours of composites are compared to experimental data found in the literature.

IF=2.371; International audience; Short-flax-fibre-composite materials are appealing for technical applications thanks to renewability, biodegradability but also potentially high ratio rigidity/density of flax fibres, in particular. However, the significant variability of technical flax fibres’ constitutive, geometrical and mechanical properties and especially lack of quantitative knowledge about its real impact on composite behaviour still prevent a widespread use of such composites. To overcome this obstacle, this study gives qualitative and quantitative information about impact of variability of flax fibre properties on numerically assessed tensile behaviour of short-flax-fibre-reinforced polypropylene, with particular attention paid to the determination of lower bound of composite behaviour. Different fibre contents and orientations, including in-plane random and distributed orientations, are considered. Results reveal that range of variation of composite behaviour strongly depends on weight of fibre contribution to composite response. It is therefore directly related to fibre content and orientation but also indirectly to manufacturing process, since this latter governs fibre orientation.

Resume Introduction La place de la maladie du Morbihan dans la nosographie est incertaine. Tantot denommee « œdeme facial persistant solide », tantot « rosacee lymphœdemateuse », elle pourrait correspondre a une forme clinicopathologique particuliere de lymphœdeme ou de rosacee. Elle est peu frequente et pose un veritable probleme de prise en charge chronique au long cours. Nous rapportons, pour la premiere fois dans la litterature francaise, un effet favorable du traitement par diuretiques dans trois cas de maladie du Morbihan. Observations Trois hommes âges de 38, 66 et 76 ans, suivis pour une maladie du Morbihan invalidante evoluant respectivement depuis deux, cinq et huit ans, presentaient un œdeme de la face predominant sur les paupieres. Le diagnostic etait retenu selon des criteres cliniques et paracliniques, apres exclusion d’un certain nombre d’affections (lupus cutane chronique, sarcoidose, causes infectieuses, notamment demodecie faciale, et enfin rosacee granulomateuse). Apres plusieurs echecs therapeutiques (cyclines, antipaludeens de synthese, danazol, corticoides et isotretinoine), ces patients ont recu un traitement par diuretiques : furosemide a la dose de 60 mg/j chez deux d’entre eux et spironolactone chez le troisieme, a raison de 75 mg deux fois par jour. Resultats Nous avons constate une regression quasi-totale, voire totale, de l’œdeme avec un recul allant d’un a 16 ans. Aucun effet secondaire n’a ete rapporte. Discussion La prise en charge de la maladie du Morbihan reste difficile et surtout empirique. Le traitement par diuretique est une alternative therapeutique interessante dans les formes severes de cette affection.

This paper deals with a viscoelastic–viscoplastic model for semi-crystalline polymers in crash applications. A polymer behaviour model is implemented in the commercial PAM CRASH© code thanks to a user material card. Global variables (load, displacement) and local variables (strain) are validated on flat and notched tensile specimens by comparing the numerical responses with data obtained by digital image correlation.

The increasing use of structural adhesives in industry encourages the need for a detailed description of their mechanical behaviour. In this paper, a structural adhesive, named BETAMATE 1496V™, which has been specially designed for applications in the automotive industry (crashworthiness) has been studied. The propose is to obtain as near a possible, a complete description of the mechanical behaviour by means of new measurement techniques, applied over a large range of strain rates using different kinds of loading devices. These results lead to important findings which we believe will have an impact on finite element modeling.

Introduction Au cours du purpura thrombopenique immunologique (PTI), le rituximab (RTX) est administre selon deux schemas : de 4 injections hebdomadaires a 375 mg/m2 « schema lymphome » ou « schema PR » (polyarthrite rhumatoide) de 1 gramme a j1 et j15. Patients et methodes Tous les malades consecutifs atteints de PTI suivis dans notre service entre janvier 2012 et juin 2018 ayant recu un traitement par RTX ont ete inclus dans cette analyse retrospective. La reponse (R) au RTX etait definie par l’obtention d’un nombre plaquettes > 30 G/L avec au moins un doublement du nombre initial et une reponse complete (RC) par un nombre de plaquettes > 100 G/L. L’existence d’un PTI secondaire etait un critere d’exclusion. Le but de notre travail est d’analyser l’efficacite du rituximab a long terme (remission qui depasse 12 mois). Les patients ayant recu le RTX selon un « schema lymphome » ont ete compare a ceux traites par « schema PR ».Resultats nous avons collige 25 patients (21 F/4H) d’âge median 39,2 ans [extremes : 16–76] ont ete inclus dans l’etude. Sept patients (28 %) ont ete traites par RTX a la phase initiale de la maladie (duree d’evolution du PTI 12 mois d’evolution).Dix huit patients (72 %)n’ avaient recu qu’une ligne therapeutique, Sept patients avaient recu au moins deux lignes therapeutiques prealablement au RTX (corticoides dans tous les cas, disulone n = 1, splenectomie n = 3, Nplate n = 1, revolade n = 1, immunoglobuline IV n = 2). Tous les patients avaient presente au moins une fois au cours du suivi des manifestations hemorragiques comprenant des manifestations severes pour 6 d’entre eux (24 %). Au total, 13 patients (52 %) ont ete traites selon le « schema PR » (groupe A) et 12 patients (48 %) selon le schema « lymphome » (groupe B). L’âge median au j1 du traitement par RTX etait comparable entre les deux groupes (39,2 versus 38 ans), la PTI etait en phase chronique pour les deux groupes. A douze mois de recul, une reponse globale etait observee chez 13 patients soit (52 %) dont neuf RC dans le groupe B comparee a 4 RC chez les patients du groupe A (p = 0,025). Conclusion Avec les limites d’un effectif relativement faible, cette etude suggere que dans le PTI ; le RTX administre selon un « schema lymphome » pourrait avoir une efficacite superieure a long terme comparativement au« schema PR » (p = 0,025). Ces resultats meritent d’etre confirmes sur un plus grand effectif de patients.

Introduction L’hemorragie intra-alveolaire (HIA) est definie par la presence diffuse dans les alveoles pulmonaires de sang provenant des capillaires ou des veinules pulmonaires. Elle traduit un saignement provenant de la microcirculation pulmonaire et doit etre distinguee d’un comblement alveolaire par du sang a la suite d’un saignement localise d’origine bronchique. L’HIA diffuse n’est pas une entite nosologique unique mais un syndrome pouvant avoir de multiples causes. La combinaison de l’HIA et de la maladie cœliaque (CD) est extremement rare ; les deux maladies peuvent avoir un lien pathogenique commun. Comme illustre par notre cas CD devrait etre specifiquement recherchee chez les patients atteints d’HIA, en particulier ceux chez qui la gravite de l’anemie est disproportionnee par rapport aux resultats radiologiques, meme en l’absence de symptomes gastro-intestinaux puisque les deux maladies peuvent beneficier d’un regime sans gluten. Observation Il s’agit d’un jeune patient âge de 17 ans, suivi pour une anemie ferriprive depuis l’enfance ; ayant comme antecedent familial un frere et une sœur suivis pour maladie cœliaque. Admis par le biais des urgences pour des episodes d’hemoptysies de moyennes abondances, avec une dyspnee stade 2 depuis cinq jours. L’examen clinique note un retard staturoponderal (RSP) et une pâleur cutaneomuqueuse, l’examen pulmonaire est normal. L’hemogramme montre une anemie hypochrome microcytaire a 10 g/dl. La radiographie thoracique met en evidence un syndrome alveolo-interstitiel bilateral. Un complement par scanner thoracique montre un aspect en verre depoli diffus correspondant a une hemorragie intra alveolaire. Le patient a ete mis en urgence sous bolus de methylprednisolone avec relai par voie orale ; et en parallele et vu l’antecedent personnel et familiale et le RSP un bilan de malabsorption objectivant une ferritinemie a 16 μg/L et cholesterol total a 0,70 g/L d’ou un complement par une fibroscopie digestive qui objective une gastrite antrofundique avec atrophie villositaire, et les Ac anti-transglutaminase, Ac anti-endomysium sont positifs. Au terme de ce bilan, le diagnostic d’HIA pulmonaire revelant une maladie cœliaque a ete retenu. L’evolution est favorable sous corticotherapie, traitement martial et regime sans gluten. Conclusion L’HIA associe une dyspnee, une hemoptysie (souvent absente), une anemie aigue, des opacites infiltrantes diffuses a l’imagerie thoracique et une hypoxemie. Le diagnostic repose sur un faisceau d’arguments et notamment sur l’imagerie et particulierement sur le LBA. Les causes d’HIA sont multiples, immunitaires ou non. Un bilan initial doit etre realise rapidement afin de rechercher une atteinte associee, notamment renale dans le cadre d’une maladie systemique, et de rechercher la maladie causale. Le pronostic immediat depend surtout de la gravite de l’atteinte respiratoire et du risque d’insuffisance respiratoire aigue.

International audience; The need to model fracture in crashworthiness by means of finite element codes is a real challenge for research. Before implementing fracture criteria, an excellent knowledge of the stress and strain states in the material just before the crack appearance is the first condition necessary to ensure the model development. At present, most of the material behaviour laws, for example for steel, are only defined until the maximum force when necking occurs. For polymers, the early occurrence of the diffuse necking leads to an experimental technique in which the speed loading is controlled in real time to maintain a constant strain rate during the test. This technique is not however used, due to technical limitations, for high strain rate behaviour laws. In this paper, the authors propose to use the heterogeneity of the displacement field on the surface of the tensile specimen as an initial condition to identify behaviour laws. The method developed uses the information in all the surface zone of the specimen by using digital image correlation. Stresses, strains and strain rates are then obtained to build a surface behaviour called the SEĖ surface. By cutting it, the experimental behaviour laws for a range of large strains and strain rates are then defined for model identification.

IF=2.035; International audience; Mechanical behaviour of short-fibre reinforced composites (SFRC) can be affected by numerous damage phenomena. This paper focuses on the modelling of fibre/matrix debonding initiated at fibre tips, which is the dominant damage mechanism when a majority of short-fibres are subjected to local tensile loadings. A failure criterion for SFRC is proposed based on a critical amount of voids located in debonded areas. Very accurate mechanical states at break can be predicted for SFRC with complex fibre distribution of orientation, for different kinds of uniaxial and biaxial tensile loadings.

International audience; Crashworthiness performance of automotives by introducing new materials is of high interest based on the global mass’ reduction of cars. Bonded techniques are tested at present with respect to the reduction of the mass/energy’s ratio combined with recycling processes. In this study, a compression test program is performed on a bulk structural adhesive under a very large range of strain rates, thus [0.1; 5000]/s. Uniaxial compression tests at 0.1 and 50/s are achieved using a high-speed hydraulic testing machine. A split Hopkinson bar’ device made of PA66 is experimented so as to characterize soft materials in the upper domain of strain rates, thus [500; 5000]/s. A special mold is used for the preparation of the adhesive plates. Two sheets are prepared (thickness 4 mm with 1 MPa pressure and 6 mm with 4 MPa pressure) in order to consider the effect of the pressure during the curing process. Water jet technique is used to extract cylindrical samples from the plates with accurate dimensions. The identification of the compression behaviour of the structural adhesive is lead with objective to find material parameters of a modified G’sell model for finite element modeling of crashworthiness.

IF=2.01; International audience; A specific damage characterization method using Digital Image Correlation for semi-crystalline polymers is proposed for a wide range of strain rates. This damage measurement is an extension of the SEĖ method [16] which was developed to characterize the behaviour laws at constant strain rates of polymeric materials. This procedure is compared to the well-known damage characterization by loss of stiffness technique under quasi-static loading. In addition, an in-situ tensile test, carried out in a microtomograph, is used to observe the cavitation phenomenon in real time. The different ways used to evaluate the damage evolution are compared and the proposed technique is also suitable for measuring the ductile damage observed in semi-crystalline polymers under dynamic loading.

The use of fabric reinforced polymers in the automotive industry is growing significantly. The high specific stiffness and strength, the ease of shaping as well as the great impact performance of these materials widely encourage their diffusion. The present model increases the predictability of explicit finite element analysis and push the boundaries of the ongoing phenomenological model. Carbon fibre composites made up various preforms were tested by applying different mechanical load up to dynamic loading. This experimental campaign highlighted the physical mechanisms affecting the initial mechanical properties, namely intra- and interlaminar matrix damage, viscoelasticty and fibre failure. The intralaminar behaviour model is based on the explicit formulation of the matrix damage model developed by the ONERA as the given damage formulation correlates with the experimental observation. Coupling with a Maxwell-Wiechert model, the viscoelasticity is included without losing the direct explicit formulation. Additionally, the model is formulated under a total Lagrangian scheme in order to maintain consistency for finite strain. Thus, the material frame-indifference as well as anisotropy are ensured. This allows reorientation of fibres to be taken into account particularly for in-plane shear loading. Moreover, fall within the framework of the total Lagrangian scheme greatly makes the parameter identification easier, as based on the initial configuration. This intralaminar model thus relies upon a physical description of the behaviour of fabric composites and the numerical simulations show a good correlation with the experimental results.

International audience; Damage evolution and characterization in semi-crystalline polymer filled with particles under various loadings is still a challenge. A specific damage characterization method using Digital Image Correlation is proposed for a wide range of strain rates considering tensile tests with hydraulic jacks as well as Hopkinson's bars. This damage measurement is obtained by using and adapting the SEE method [1] which was developed to characterize the behaviour laws at constant strain rates of polymeric materials in dynamic. To validate the characterization process, various damage measurement techniques are used under quasi-static conditions before to apply the procedure in dynamic. So, the well-known damage characterization by loss of stiffness technique under quasi-static loading is applied to a polypropylene. In addition, an in-situ tensile test, carried out in a microtomograph, is used to observe the cavitation phenomenon in real time. A good correlation is obtained between all these techniques and consequently the proposed technique is supposed suitable for measuring the ductile damage observed in semi-crystalline polymers under dynamic loading. By applying it to the semi-crystalline polymer at moderate and high speed loadings, the damage evolution is measured and it is observed that the damage evolution is not strain rate dependent but the failure strain on the contrary is strain rate dependent.

To accurately predict the damage and failure evolution occurring in crashworthiness and sheet metal-forming simulations, a realistic material description is required. The parameters needed to describe such damage models are not easy to obtain and there is no direct test to achieve these parameters. An inverse method to identify the Gurson and Lemaitre damage model parameters is presented. Quasi-static and high-rate tensile tests have been carried out on thin notched specimen made of high-strength steel (THR800) from ARCELOR. The aim was to study the combined effects of strain rate and stress triaxiality on the damage material behaviour. Macroscopic measured responses are the global forces and the width at the bottom of the notch versus the elongation. An image-processing software has been developed to measure the evolution of the width at the bottom of the notch versus the elongation from the video tests. The damage parameters are identified by correlating experimental and numerical macroscopic m...

International audience; Epoxy resins are widely used in Carbon Fiber Reinforced Polymers (CFRPs) for the aeronautical industry. They must ensure cohesion in most of the structural composite parts incorporated into the modern manufactured aircrafts. So fracture properties of epoxy resins are essential features to resist critical decohesions in case of impact. Surprisingly however, there are few experimental studies dedicated to the dynamic fracture of these thermoset polymers. Therefore, this research aims at developing an experimental procedure to characterize the dynamic fracture toughness of epoxy resins during propagation. Since glassy polymers exhibit viscous fracture, the crack speed å is known for influencing the toughness of these materials. Then a strain gage method is proposed to determine the mode I dynamic energy release rate G ID for various crack speeds å. Thus an experimental set-up is defined to simultaneously implement strain gage measurement and high speed cinematography. Finally, preliminary results are briefly reported to demonstrate the method validity.