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Resume Introduction La luxation radio-carpienne (LRC) se definit par une perte de contact totale des surfaces articulaires du carpe avec la surface articulaire radiale. Rare, peu de series ont ete publiees sur le sujet. L’objectif de notre etude etait d’apprecier les resultats fonctionnels apres chirurgie, en particulier sans reparation ligamentaire, d’une LRC. Hypothese Le resultat fonctionnel postoperatoire a distance est satisfaisant pour une utilisation du poignet dans les activites de vie quotidienne. Materiels et methodes Une etude retrospective a ete menee de janvier 2012 a juillet 2017. Les criteres d’inclusion etaient la presence d’une LRC sur les radiographies preoperatoires chez des sujets majeurs et un recul minimum de 6 mois ; les criteres d’exclusion etaient la presence de cartilages de croissance non fusionnes et une fracture de l’epiphyse radiale distale a grand deplacement. Le type de LRC etait evalue par la classification de Dumontier. Le resultat fonctionnel etait evalue par les amplitudes articulaires postoperatoires du poignet, la force de prehension (Jamar®), les scores fonctionnels QuickDash, et Green O’Brien modifie par Cooney. Resultats Quatorze patients ont ete revus a 31 mois (7–60). Trois patients presentaient une LRC de type I, 11 de type II. Tous les patients ont ete pris en charge chirurgicalement. Aucune suture ligamentaire n’a ete realisee. La flexion moyenne etait de 63° (20–90°), l’extension de 51° (25-90°), la pronation de 79° (60–90), la supination de 80° (50–90), la force de prehension de 27,9 kg (8–40). Le QuickDASH et le score de Green O’Brien modifie par Cooney moyens etaient respectivement de 25,6 (4,54–40,9) et de 74 (35–100). Discussion Nos resultats fonctionnels etaient satisfaisants et comparables a la litterature, et ce, malgre l’absence de suture ligamentaire radio-carpienne, dans les LRC de type I. Niveau de preuve IV.

Mesenchymal stromal cells (MSCs) exhibit anti-inflammatory and immune-regulatory properties, and preclinical studies suggest a potential benefit in solid organ transplantation. We report on the 1-year follow-up of an open-label phase I-II trial of a single infusion of third-party MSC post-kidney transplantation, in addition to standard immunosuppression. Ten kidney transplant recipients from deceased donors received third-party bone marrow MSCs (∼2 × 106/kg) on day 3 ± 2 post-transplant and were compared to 10 concurrent controls. No adverse effects were noted at MSC injection. One participant with a history of cardiac disease had a non-ST-elevation myocardial infarction approximately 3 hours after MSC infusion. Incidences of opportunistic infections and acute rejection were similar. At day 7 post-transplant, estimated glomerular filtration rate (eGFR) in MSC-treated recipients reached 48.6 ml/min/1.73m2, compared to 32.5 ml/min/1.73m2 in controls and 29.3 ml/min/1.73m2 in our overall cohort of kidney transplant recipients. No difference in eGFR was found at 1 year. MSC-treated recipients showed increased frequencies of regulatory T cells at day 30, with no significant change in B cell frequencies compared to concurrent controls. Four MSC-treated participants developed antibodies against MSC or shared kidney-MSC HLA, with only 1 with MFI >1500. A single infusion of third-party MSC following kidney transplantation appears to be safe, with one cardiac event of unclear relationship to the intervention. MSC therapy is associated with increased regulatory T cell proportion and with improved early allograft function. Long-term effects, including potential immunization against MSC, remain to be studied.

Resume Objectif Il existe une correlation entre la reussite d’une greffe de sang de cordon et le nombre de cellules souches hematopoietiques (CSH) presents dans une unite de don de sang de cordon prelevee lors de l’accouchement. L’objectif de cette analyse est de mettre en evidence des facteurs obstetricaux qui peuvent influencer la qualite d’une unite de sang de cordon. Methodes Une etude retrospective a ete realisee a la banque de sang de cordon de Liege sur un echantillon de 7,463 unites de sang de cordon prelevees entre 2000 et 2016. Huit variables obstetricales ont ete analysees par rapport a deux variables dependantes : le nombre de cellules nucleees totales (CNT) et le volume d’une unite de sang de cordon. Le test de Welch, les medianes et les percentiles 25 et 75 et le test non-parametrique de Mann-Whitney Wilcoxon ont ete utilises. Resultats Les parametres obstetricaux qui influencent la qualite de l’unite de sang de cordon sont : le clampage du cordon (> 15 secondes), l’utilisation d’ocytociques durant le travail, un âge gestationnel plus avance (38–41 semaines), un poids du nouveau-ne plus eleve (> 3300 gr) et un poids du placenta plus important (> 500 gr). Un nouveau-ne de sexe feminin et l’utilisation d’une peridurale sont associes significativement (p Conclusion Le poids du nouveau-ne, le poids du placenta, l’âge gestationnel et le clampage du cordon sont des parametres qui pourraient etre utilises par les maternites, comme indicateurs des naissances qui menent a des unites de sang de cordon plus volumineux et plus riches en CNT.

Objectif Malgre l’optimisation de l’equilibre metabolique pendant la grossesse, les complications materno-fœtales des diabetiques de type 1 (DT1) restent superieures a celles de la population generale. L’objectif etait d’evaluer si les taux d’HbA1c avaient une valeur predictive des complications. Patients & methode s Etude retrospective de 678 grossesses DT1 au CHU de Lille (1997-2019). L’association entre variations de l’HbA1c et complications a ete etudiee. Le critere composite (CC) a ete defini comme au moins une des complications suivantes: prematurite, preeclampsie, LGA, SGA ou cesarienne. Resultats Parmi les 678 naissances, l’HbA1c mediane pregestationnel etait de 7,2 % (6,5 % a 8,1 %), Le taux de LGA etait de 56 % et de SGA de 4,5 %. 504 etaient des naissances sans accouchement premature (76,1 %). Le CC est present dans 81,8 %. Une HbA1c plus elevee au cours du 1er trimestre etait associee au CC (OR = 1,04 [IC 95 %, 1,02 a 1,06] pour une augmentation de 0,1 %; p Discussion L’HbA1c est associee aux complications materno-fœtales. Malgre l’optimisation de l’equilibre metabolique au 3e trimestre, pour les patients presentant un desequilibre glycemique precoce, le risque de macrosomie persistait. L’HbA1c est un marqueur pour surveiller l’equilibre glycemique permettant une prise en charge personnalisee qui pourrait etre couplee a la mesure continue de glucose.

The objective of this study is to develop a numerical tool using the commercial software, Abaqus and Python, to predict the fatigue crack front shape while taking into account the influence of plasticity induced crack closure on crack propagation in three Dimensional (3D) structures. In this aim, a 3D model of a compact tension specimen made out of stainless steel 304L, and subjected to a constant loading scheme, is proposed. The crack propagation is considered to be driven by the stress fields developed in the vicinity of the crack tip and thus by the stress intensity factor K. Two parallel simulations are used: an elastic simulation intends to calculate the local maximum stress intensity factor while the other, an elasto-plastic one, aims at obtaining the plastic wake and the resulting crack closure load. The results of both simulations are combined in order to constitute the effective stress intensity factor range, which is in turn used, along with Paris law, to calculate the crack propagation along the thickness. The local crack advancements obtained allow to construct the new crack front. Finally, a node release technique is used with geometry remeshing to issue new iterations with new boundary conditions that respond to the changes in the crack front. The procedure is repeated until the stabilization of the effective stress intensity factor values all along the specimen thickness is reached. The results obtained are compared with previously issued experimental results, showing very good results in small scale yielding and beyond that a large dependency on the plastic zone size developed in the neighborhood of the crack front.

Several studies have reported an impact of adult hematopoietic stem cell donor cytomegalovirus (CMV) serostatus on allogeneic hematopoietic cell transplantation outcomes. Limited data, however, are available on the impact of cord blood unit (CBU) CMV serostatus on allogeneic umbilical cord blood transplantation (UCBT) outcomes. We analyzed, retrospectively, the impact of CBU CMV serostatus on relapse incidence (RI) and 2-year nonrelapse mortality (NRM) of single-unit CBU transplantation for acute leukemia. Data from 1177 de novo acute leukemia pediatric and adult patients transplanted within European Group for Blood and Marrow Transplantation centers between 2000 and 2012 were analyzed. CBUs were provided by the European Cord Blood Banks. The median follow-up time for live patients was 59.9 months. The recipients of CMV-seropositive and -seronegative CBUs showed a comparable RI (33% versus 35%, respectively, P = .6) and 2-year cumulative incidence of NRM (31% versus 32%, respectively, P = .5). We conclude that CBU CMV serostatus did not influence RI and NRM in de novo acute leukemia patients after allo-UCBT and should not be included as a criteria for cord blood choice.

Fatigue crack growth was investigated in commercially pure Ti grade 4 processed by severe plastic deformation. The ultrafine-grained structure was prepared by means of equal channel angular pressing technique followed by cold drawing. The growth of fatigue cracks was investigated also in the as-received coarse-grained state of material for comparison. The fatigue crack growth rate in the ultrafine-grained material was found to be higher and the threshold stress intensity range ΔKth for crack growth lower than in the coarse-grained Ti, 2.5 and 4.7 MPa m1/2, respectively. A combination of transcrystaline and intercrystaline crack growth was typical for all crack growth rates in the coarse-grained material. Contrary to the combined fracture mechanism in coarse-grained Ti only transcrystalline crack growth was a characteristic feature of crack propagation in the ultrafine-grained material. It has been found that the experimentally and theoretically determined values of closure are in reasonable agreement. Crack closure calculated according to the Newman model taking into account only plasticity induced closure was in the range from 67% to 69% of Kmax for as-received and 70% for UFG state of material. Crack closure determined experimentally was 67% of Kmax for as-received and 67% for UFG CP Ti grade 4. Investigation of fracture surfaces did not bring any evident signs of the effects of fracture surface morphology resulting in roughness induced closure or oxide induced closure under testing conditions used. This indicates that plasticity induced closure seems to be a dominant closure mechanism in both states of the investigated Ti grade 4.

Turbo generators for nuclear plants are mostly equipped with hydrogen cooling systems. Current practice of characterizing the growth of fatigue cracks on the basis of fracture mechanics primarily relies on fatigue tests for long cracks which are typically of several millimeters in length. However, in view of extended life for the plants, the damage tolerance evaluation of such fatigue-critical engineering components requires understanding of the propagation of cracks of significantly smaller dimensions. Then the near threshold of short cracks is investigated and compared to the behavior of long crack by experiments under 4 bar hydrogen atmosphere. The short crack fatigue propagation in hydrogen atmosphere is shown similar to that in air, growing faster than the long crack and at ΔK ranging below the long crack threshold; this effect is related to a reduced crack closure shielding. The propagation behavior of long crack under hydrogen atmosphere is shown similar to that obtained in air in the low rate range, i.e. when the maximum of the stress intensity factor K max is lower than a critical level of about 16 MPa m 1/ 2 with higher crack growth rate than in high vacuum. This environment effect is related to the presence of residual water vapor in both gases. For higher K max , much faster growth rates under hydrogen atmosphere in comparison to air and vacuum are observed and related to hydrogen assisted intergranular propagation combining fatigue and sustained loading damage. The results are discussed on the basis of micrographic observations supporting the involved mechanisms.

To date, despite an existing regulatory framework and standards, there are no true technical recommendations. A survey of 23 cell processing facilities (France, Belgium and Switzerland) has allowed to overview current practices according to cellular products specifications upon arrival at the facility, with modalities for their preparation prior to cryopreservation, storage, thawing and finally for infusion to patient. Data analysis shows great variability of collected volumes and cell concentrations in cellular products. Despite homogeneous practices for handling cells at the facility, methods vary between centers, especially for the choice of cryoprotective solutions and thawing methods. During the workshop, practices have been discussed and summarized to write of recommendations about the following topics: processing and cryopreservation, thawing, bedside precautions (for infusion). This work identifies some improvements in terms of collection, choice of wash solution of thawed cells and validation of the conditions of carriage.

An efficient and direct approach was developed for the synthesis of α,β-dehydroamino acid derivatives with a broad range of substrates. Amido-substituted Malonic Acid Half Oxyesters (MAHOs) have proven to be excellent partners of various aromatic aldehydes in the presence of secondary amine, trifluoromethanesulfonic acid to perform a Knoevenagel–Doebner condensation under mild conditions with good to excellent yields. A mechanistic study revealed that the sequence involved the formation of an iminium intermediate to provide stereoselectively Z-α,β-unsaturated amino acids.

The fatigue crack propagation threshold ΔKth is of paramount importance for any kind of damage tolerant design, but in contrast to this importance, the determination and application of the parameter is not on the firm ground as previously assumed. The paper discusses questions of its experimental determination as well as of its application to components. In both fields, new questions have been raised with the potential to challenge or modify long-standing knowledge. Against this background, the paper is an attempt to systematize the established knowledge as well as questions and open issues.

The influence of frequency (20kHz ultrasonic tests and conventional 20 to 35Hz tests) and environment (air and vacuum) on near-threshold fatigue crack propagation of three metallic alloys, Ti-6Al-4V, 2024-T351 and 12% Cr stainless steel is compared experimentally. The effective stress-intensity factor which is considered as the propagation driving force is determined from closure measurements or tests run at high R-ratio. Based on microfractographic observations, the results are discussed in terms of a preexisting model for intrinsic and environmentally assisted fatigue crack propagation.

Damage tolerance is today imposed by the regulations to dimension aeronautical turbine critical parts. Thus resistance of these parts to potential anomalies is assessed. It requires to study, besides standard long cracks, the propagation of cracks of little dimension (some tenth of mm for initial length) which can have an atypical behavior consisting in crack propagation at lower stress intensity factor range than the threshold for long crack. In this context, this study is focused on a bimodal Titanium alloy (TA6V) tested at different temperatures: room temperature and 400°C at a low load ratio R of 0.1, which corresponds to loading of manufactured compressor impellers in these materials. Tests are run on compact tension specimens initially pre-cracked at constant applied stress intensity factor range (ΔK) and then cracked to threshold in view of obtaining a long crack of a/W˜0,5. Physically 2D through-thickness short fatigue cracks are created by gradually removing the plastic wake of this long crack in order to obtain a crack length as short as possible (0.1 mm). Next the short crack obtained is propagated in view of getting different thresholds for different crack lengths according to a procedure of load decrease. Crack closure contribution is systematically measured using the compliance variation technique with numerical data acquisition and filtering for accurate detection of the stress intensity factor (SIF) at the crack opening. 2D short crack propagation behavior is compared to long crack behavior with a special attention given to crack closure. The threshold evolution in function of the crack length is investigated using a Kitagawa diagram approach for determining a non-propagation criterion of short cracks.

Resume Selon l’etude Diabetes Attitudes, Wishes, and Needs 2 (DAWN2™), malgre le soutien apporte par les equipes soignantes, une attention encore insuffisante est portee aux aspects psychologiques du vecu du diabete. L’amputation est l’une des trois complications qui retentit le plus sur la qualite de vie des patients diabetiques. Nous avons cherche a explorer le vecu singulier de la premiere amputation, du point de vue du patient diabetique lui-meme. Par une etude qualitative, douze entretiens ont ete menes. Les patients diabetiques selectionnes avaient un antecedent d’amputation d’orteil depuis au moins 6 mois, et consultaient dans le cadre d’une surveillance habituelle. Une annonce bien effectuee a ete retrouvee comme essentielle au bon vecu de cette amputation. Les criteres mis en evidence d’une « bonne annonce », selon ces patients, etaient une annonce anticipee, survenant dans le cadre d’un sauvetage de membre, de facon claire. Cette annonce a ete l’amorce d’une modification de comportement authentique, mais fragile, et qui doit etre entretenue.

Thousands of autologous and at less extent allogeneic hematopoietic stem cells (HSC) bags are cryopreserved in France. The majority of autologous HSC grafts are used within a year after collection. However, many bags are still unused and cryopreserved for many years. In France and on a European scale, the ever-growing number of cryopreserved bags represents a real economic health concern. Indeed, the cost of storage is about 100€ per bag and per year. In addition, quality and therapeutic value of these long-term cryopreserved grafts needs to be evaluated. In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapies (SFGM-TC) set up its fourth annual series of workshops which brought together practitioners from its member centers across France. These workshops took place in September 2013 in Lille. In this article, we addressed the issue of the destruction of long-term cryopreserved grafts be them autologous or allogeneic and provide recommendations regarding their destruction.

Introduction La prise en charge d’une arthrite septique de hanche chez l’enfant est une urgence chirurgicale. Devant un tableau clinique associant flexum de hanche et fievre, l’echographie comparative qui peut etre realisee par le chirurgien permet de confirmer le diagnostic et de poser l’indication chirurgicale. Si la ponction-lavage a l’aiguille est un moyen simple et rapide, ce geste expose neanmoins a un taux de recidive eleve. Le but de notre etude est de montrer que l’arthroscopie de hanche par abord extracapsulaire de dehors en dedans est une alternative efficace et accessible en urgence. Materiel et methodes Nous rapportons 2 cas (7 ans–135 cm ; 13 ans–143 cm) d’echec de ponction-lavage a l’aiguille traite dans un deuxieme temps par arthroscopie de hanche. La technique extracapsulaire de dehors en dedans a ete realise sous controle radioscopique et arthroscopique sur table orthopedique classique, a l’aide d’un arthroscope a 30 degres et d’un couteau motorise de diametre 3,5 mm. Par 2 abords anterolateraux proximal et distal par rapport au muscle tenseur du fascia lata, il a ete successivement realise sans ancillaire dedie, une capsulotomie anterieure longitudinale minimale, des prelevements, un lavage par 3 poches de 3 litres, l’ablation des fausses membranes, des biopsies synoviales, une synovectomie partielle, un bilan cartilagineux du compartiment central puis peripherique et la mise en place d’un drainage du compartiment peripherique. Resultats Cette prise en charge a permis dans les deux cas, la disparition complete de l’epanchement et la normalisation progressive du bilan inflammatoire sous antibiotherapie sans re intervention et sans complication lie a l’abord. L’appui etait repris a 3 semaines. Le suivi, respectivement a 6 mois et 15 mois de recul retrouve dans les deux cas, apres la reprise des activites sportives, un examen indolore de la hanche et l’absence d’atteinte radiologique. Discussion Cette technique d arthroscopie de hanche est la seule accessible dans le cadre de l’urgence car independante d’un ancillaire. Elle parait ainsi sans risque pour le cartilage ou le labrum. L’utilisation d’un arthroscope de 4,5 mm de diametre est possible a partir de 7ans–130 cm. La disponibilite et l’utilisation d’un arthroscope de 2,9 mm est a anticiper en dessous de cette taille. Conclusion L’arthroscopie de hanche par abord extracapsulaire de dehors en dedans nous semble pouvoir repondre efficacement aux cas d’echec de ponction-lavage a l’aiguille de l’arthrite septique de hanche de l’enfant. Elle pourrait etre propose en premiere intention en urgence en cas d’arthrite septique purulente ou de prise en charge tardive, en remplacement de l’arthrotomie.

International audience; The fatigue threshold is determined experimentally following international standards, but its measurement is laborious and time consuming. This paper proposes a numerical approach to determine the fatigue threshold based on the analysis of the crack tip opening displacement, CTOD, evaluated using the finite element method. It assumes that fatigue crack propagation only occurs with plastic deformation at the crack tip. However, a factor of about two was found between the numerical predictions and experimental results of effective fatigue threshold from literature. This difference was attributed to a different mechanism of fatigue crack growth at relatively low load ranges, resulting from environmental effects at the crack tip. Therefore, the approach proposed is adequate to predict the fatigue threshold in vacuum, which is supposed to be controlled by crack tip plastic deformation.