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Resume L’activite d’hospitalisation a domicile (HAD) a double ces 10 dernieres annees, pour repondre a une demande croissante des patients a etre soignes chez eux, couplee a la recherche d’une plus grande maitrise des depenses hospitalieres. L’activite pediatrique reste marginale ; elle releve le plus souvent d’une expertise pediatrique au sein de certains etablissements HAD. Elle est essentiellement pratiquee par les HAD specialisees en pediatrie. Nous dressons un etat des lieux de l’activite pediatrique en HAD en France selon les donnees du Programme de medicalisation des systemes d’information (PMSI) et de la Federation nationale des etablissements d’HAD (FNEHAD). La repartition des equipes d’HAD pediatriques est inegale sur le territoire : 19 HAD pediatriques polyvalentes ou specialisees sur 8 regions en metropole et 2 en departements et regions d’Outre-Mer. L’activite pediatrique represente 4,7 % de l’activite totale des HAD, avec 60 % d’enfants de moins de 3 ans. En 2017, plus de la moitie des sejours pediatriques en HAD correspondaient a des pathologies perinatales (32 %) ou malignes (20 %). Pour faciliter l’acces aux soins en HAD des enfants quels que soient leurs lieux de vie, l’Association francaise des pediatres coordonnateurs d’HAD (AFPHAD) a ete creee en juin 2018 avec pour objectif principal de promouvoir l’activite pediatrique en HAD. Elle travaille notamment sur 2 points : une organisation du parcours des enfants relevant de soins hospitaliers et une revalorisation des sejours pediatriques (frein au developpement des activites pediatriques en HAD).

Resume Introduction Le Reseau Enfance et Handicap du grand Sud Ouest (REHSO) a ete fonde en novembre 2015 pour promouvoir la reeducation pediatrique sur ce territoire et harmoniser les pratiques au sein des structures participantes. Materiels et methodes En mai 2015, un etat des lieux sur la gestion des projets chirurgicaux chez les enfants en situation de handicap a ete dresse a partir d’un questionnaire adresse aux structures de reeducation pediatrique du grand ouest. Puis en juin 2015, un groupe de travail compose de 17 medecins pediatres, MPR et chirurgiens s’est reuni pour echanger sur leurs differentes pratiques et construire un consensus sur les etapes a mener lors d’un projet chirurgical chez l’enfant handicape. Dans un troisieme temps, ce consensus a ete conforte par les donnees de la litterature sur le parcours de soins de l’enfant en chirurgie. Resultats Sur les 12 sollicites, 7 centres ont repondu a l’enquete preliminaire. Les constats positifs etaient que tous ces centres realisaient une consultation multidisciplinaire, essentiellement en CHU, avant les interventions chirurgicales et que la majorite des centres pratiquaient une preparation a la chirurgie, plus ou moins formalisee. Les points faibles des parcours etaient que l’evaluation de la douleur, bien que systematique, n’etait pas suffisamment formalisee, que les transmissions pre- et postoperatoires manquaient de precision, et que l’accompagnement specifique des familles autour du projet chirurgical etait peu developpe. Le consensus elabore par le REHSO structure le parcours de l’enfant en chirurgie en prise en charge d’amont, periode operatoire, temps de la sortie d’hospitalisation, et prise en charge d’aval. Il souligne l’importance de la preparation multidisciplinaire a la chirurgie, de l’information aux familles, de la gestion de la douleur, et de la qualite des transmissions et du suivi. Il preconise notamment l’utilisation systematique des fiches de liaison de la mission handicap de l’AP–HP, et de la FLACC modifiee pour l’evaluation de la douleur. Conclusion Les 17 signataires de ce consensus se sont engages a le diffuser et le faire appliquer dans leurs etablissements respectifs.

International audience; AbstractA radiochemical method for producing 82Se sources with an ultra-low level of contamination of natural radionuclides (40K, decay products of 232Th and 238U) has been developed based on cation-exchange chromatographic purification with reverse removal of impurities. It includes chromatographic separation (purification), reduction, conditioning (which includes decantation, centrifugation, washing, grinding, and drying), and 82Se foil production. The conditioning stage, during which highly dispersed elemental selenium is obtained by the reduction of purified selenious acid (H2SeO3) with sulfur dioxide (SO2) represents the crucial step in the preparation of radiopure 82Se samples. The natural selenium (600 g) was first produced in this procedure in order to refine the method. The technique developed was then used to produce 2.5 kg of radiopure enriched selenium (82Se). The produced 82Se samples were wrapped in polyethylene (12 μm thick) and radionuclides present in the sample were analyzed with the BiPo-3 detector. The radiopurity of the plastic materials (chromatographic column material and polypropylene chemical vessels), which were used at all stages, was determined by instrumental neutron activation analysis. The radiopurity of the 82Se foils was checked by measurements with the BiPo-3 spectrometer, which confirmed the high purity of the final product. The measured contamination level for 208Tl was 8–54 μBq/kg, and for 214Bi the detection limit of 600 μBq/kg has been reached.

A prototype of a picosecond x-ray streak camera has been developed and tested by Commissariat a l’Energie Atomique et aux Energies Alternatives to provide plasma-diagnostic support for the Laser Megajoule. We report on the measured performance of this streak camera, which almost fulfills the requirements: 50-μm spatial resolution over a 15-mm field in the photocathode plane, 17-ps temporal resolution in a 2-ns timebase, a detection threshold lower than 625 nJ/cm2 in the 0.05–15 keV spectral range, and a dynamic range greater than 100.

Tritiated water has been standardized in the framework of a French–Romanian cooperation by two improved methods: liquid scintillation counting based on the triple to double coincidence ratio method and the internal gas proportional counting used in conjunction with a tritium generator for chemical reduction of water. The uncertainties of measurement for both methods were smaller than 0.6% and the two results were consistent within these uncertainties, indicating that either method is equally suited for standardizing tritiated water.

Resume Inscrites en preambule dans toutes les recommandations officielles sur la prise en charge de l'hypertension arterielle, les mesures hygienodietetiques ont fait la preuve de leur efficacite sur la reduction des chiffres de pression arterielle. Bien que l'impact reel de ces mesures non medicamenteuses sur le niveau de risque cardiovasculaire prete encore a discussion, elles sont ou devraient etre partie prenante du traitement antihypertenseur. Les cinq mesures efficaces sont : la reduction ponderale, un regime peu sale, une alimentation de type DASH (Dietary Approaches to Stop Hypertension) (favorisant les fruits, les legumes et les produits alleges en graisse), la pratique d'une activite physique et la reduction de la consommation d'alcool. Ces modifications de l'hygiene de vie ont demontre leur capacite a reduire la pression arterielle, quel que soit le niveau tensionnel initial. Il semble raisonnable de considerer que ces mesures non medicamenteuses agissent de facon au mieux additive avec les therapeutiques pharmacologiques. Sachant qu'il est toujours tres difficile d'obtenir une bonne observance des patients a ces mesures souvent contraignantes, l'education pour la sante et les mesures de sante publique devraient etre associees au colloque singulier pour esperer controler efficacement la pression arterielle en population generale.

Resume Objectif – Le but de ce travail a ete de comprendre les motivations et les obstacles dans le choix ou la poursuite de l'allaitement maternel. Population et methodes – L’enquete a ete menee aupres de 308 femmes ayant accouche depuis au moins trois mois a l'aide d'un auto-questionnaire distribue par des medecins ou des sages-femmes tires au sort sur une liste professionnelle departementale. Resultats – L'enquete a montre que l’allaitement maternel n’etait choisi que dans 50,6 % des cas et que sa duree moyenne etait de deux mois. Il s’agissait surtout des femmes de plus de 35 ans, multipares, ayant des antecedents d’allaitement personnel au sein et ayant suivi les cours de preparation a l’accouchement. La poursuite d’une relation mere–enfant (82 %) et le caractere adapte du lait (84 %) restaient les principales motivations dans ce choix. La crainte des affections mammaires (22 %) et les contraintes de disponibilite (50 %) semblaient orienter les femmes vers un allaitement artificiel. Cependant, le prix eleve du lait en poudre (38 %) et l’apparition de troubles digestifs chez l’enfant (29 %) constituaient un facteur limitant. Conclusion – La relance de l’allaitement maternel doit passer par des mesures incitatives financieres et sociales. L’encadrement des femmes allaitantes doit etre ameliore notamment par une meilleure formation des personnels de sante.

Commissariat a l’Energie Atomique et aux Energies Alternatives has developed the ARGOS X-ray framing camera to perform two-dimensional, high-timing resolution imaging of an imploding target on the French high-power laser facility Laser MegaJoule. The main features of this camera are: a microchannel plate gated X-ray detector, a spring-loaded CCD camera that maintains proximity focus in any orientation, and electronics packages that provide remotely-selectable high-voltages to modify the exposure-time of the camera. These components are integrated into an “air-box” that protects them from the harsh environmental conditions. A miniaturized X-ray generator is also part of the device for in situ self-testing purposes.

The present study was aimed at identifying surface-membrane molecules involved in the regulation of human B-cell ontogeny. For this purpose, murine monoclonal antibodies (MoAbs) were generated against Pre-Alp, a pre-B acute lymphoblastic leukemia (ALL) cell line, and MoAb R34.34 was selected for further characterization. R34.34 recognized a molecule expressed on normal B-cell precursors (BCP) but not on mature B cells. The antibody also reacted with T lymphocytes, a subpopulation of monocytes from peripheral blood, and a subset of CD34+ cells. Immunoprecipitation analysis indicated that R34.34 recognizes an 80-kD molecular weight antigen. Antibody R34.34 was further found to be directed against an epitope interfering with binding of interleukin-7 (IL-7) to Pre-Alp cells. Expression cloning from a Pre-Alp cDNA library showed that R34.34 antigen is CDw127, the 75- to 80-kD IL-7 receptor. Proliferation of the B-lineage ALL cell lines Reh and Mieliki was inhibited by IL-7, and this effect was specifically reverted by MoAb R34.34. In addition, antibody R34.34 specifically inhibited IL-7- dependent proliferation of normal BCP, Pre-Alp cells, and peripheral T cells. These results imply that both inhibitory and proliferative effects of IL-7 can be mediated through the same receptor on various lineages. R34.34 antibody should be important for the analysis of signal transduction through CDw127.

One of the relevant processes driven by political discussion under the United Framework Convention on Climate Change is the monitoring of Essential Climate Variables. Land Cover is one of those variables and efforts are therefore to be made to develop land cover observation approaches which meet the climate modelling community expectations. This paper aims at contributing to this necessity. First, consultation mechanisms were established with the climate modelling community to identify its specific requirements in terms of satellite-based global land cover products. This assessment highlighted specific needs in terms of land cover characterization and products accuracy, stability and consistency that are currently not met. Based on this outcome, the paper calls into question the current land cover representation and for revisiting global land cover mapping approaches. Increasing the flexibility of current classification systems and making the mapping techniques less sensitive to the period of observation are proposed as two key aspects to enhance the usability of global land cover dataset.

We have recently demonstrated that tumor necrosis factor alpha (TNF-alpha) potentiates interleukin 3 (IL-3) and granulocyte/macrophage colony-stimulating factor-induced growth of CD34+ hematopoietic progenitor cells (HPC), and favors the generation of dendritic/Langerhans cells. The stimulatory effect of TNF-alpha was detailed in the present study. Thus, CD34+ HPC entering in cycle (S/G2M) after a 48-h pulse with IL-3 expressed the transferrin receptor (TfR), and fluorescence-activated cell sorter-separated TfR+ HPC, but not TfR-HPC, showed a high proliferative response to IL-3. In contrast, TfR-HPC were found to undergo strong proliferation in response to IL-3 + TNF-alpha. Limiting dilution experiments indicated that TNF-alpha increased both the frequency and the average size of clones generated from TfR-HPC as a result of the development of a higher number of large clones. In contrast, TNF-alpha did not enhance the IL-3-dependent proliferation of TfR+ HPC. Preculturing CD34+ HPC for 48 h with TNF-alpha enhanced the subsequent generation of IL-3-dependent colony-forming units. Precultures with TNF-alpha or cultures with suboptimal doses of TNF-alpha allowed the recruitment of cells with both granulocytic and monocytic differentiation potential. Taken together, our results indicate that TNF-alpha recruits a subpopulation of CD34+ HPC hyposensitive to IL-3, with high proliferative capacity and some features of multipotential progenitors, that are likely to be more primitive than those responding to IL-3 alone.

The CD40 surface membrane molecule plays an important role in the activation of mature human B cells, but its role in earlier stages of B lineage development is unknown. Here, we have investigated the effects of triggering the CD40 antigen on B cell precursors (BCP) by crosslinking with anti-CD40 antibody presented by Fc gamma-receptor type II-transfected murine Ltk- cells (CD40 system). CD10+ surface immunoglobulin negative (sIg-) BCP, freshly isolated from fetal bone marrow or precultured on stromal cells, proliferated in the CD40 system. This effect required the presence of IL-3, which acted as a specific cosignal among a panel of cytokines examined. The association of IL-10 and IL-7 potentiated the observed IL-3 and CD40-dependent BCP proliferation, demonstrating that IL-10 can act on early B lineage cells. CD40-dependent activation of fetal BCP did not favor maturation to sIg+ B cells, but resulted in the induction of high levels of surface membrane CD23. The emerging CD23+ BCP lacked sIg and CD10, and represented an important proportion of the cycling cells in the CD40-dependent cultures. Taken together, our data demonstrate that stimulation of the CD40 antigen induces expression of the CD23 gene, and regulates cell proliferation during normal human B cell ontogeny.

Numerous studies have shown that interferon-gamma (IFN gamma) inhibits the proliferative effects of colony-stimulating factors (CSFs) on human bone marrow cells. In the present study we investigated the effects of IFN gamma and other described inhibitory factors on the proliferation of highly purified CD34+ human hematopoietic progenitor cells (HPC) in response to recombinant CSFs. While transforming growth factor-beta (TGF beta) and IFN alpha were highly inhibitory, IFN gamma strongly potentiated interleukin-3 (IL-3) and, to a lesser extent, granulocyte- macrophage-CSF (GM-CSF) induced growth of CD34+ HPC. IFN gamma had no significant proliferative effect per se, and did not affect granulocyte- CSF (G-CSF)-dependent cell proliferation. Within 10 days the number of viable cells generated in the presence of IL-3 + IFN gamma was two times higher than in the presence of IL-3 alone. Limiting dilution analysis showed that IFN gamma acts directly on its target cell to increase the frequency of IL-3-responding cells without affecting the average size of the IL-3-dependent clones. Enhanced frequency of IL-3- and GM-CSF-responding cells was also observed in colony assays where the addition of IFN gamma increased by twofold to threefold the number of granulocyte colony-forming units (CFU-G), macrophage CFUs (CFU-M), granulocyte-macrophage CFUs (CFU-GM), and mixed erythroid (E-MIX). In contrast, IFN gamma did not affect the generation of erythroid burst- forming units (BFU-e) in such cultures. In longer-term culture, the combination of IFN gamma and IL-3 did not alter the lineage distribution of the cells when compared with IL-3 alone. However, after 15 days, when mature cells were present in the cultures, IFN gamma displayed cell concentration-related growth-inhibitory effects. Thus, IFN gamma appears to stimulate the early stage of myelopoiesis by enhancing the frequency of growth factor-responding cells but, unlike tumor necrosis factor alpha (TNF alpha), does not alter cell differentiation.

Two electron spectrometers have been developed for the characterisation of scintillating counters with MeV range electrons. These spectrometers offer a monoenergetic electron beam ranging from 0.4 to 1.8 MeV with an energy resolution (FWHM) of 1.0 ± 0.2% at 1 MeV and a linearity better than 2%. The transverse profile of the beams consists of a typical 3.0 mm Gaussian width. These electron beams can automatically scan surfaces up to 60 × 200 cm2 in 1 mm increments. They have been used in the calorimeter module development for the SuperNEMO experiment.

This paper describes the framework used by the Canadian Food Inspection Agency to assess the risks to animal health associated with biotechnology-derived animals and their products. In Canada the risks to animal health associated with biotechnology-derived animals are one consideration among several other regulatory concerns (e.g. human health, the environment). The risk analysis process begins with hazard identification, includes a risk assessment for each hazard, and concludes with risk management and risk communication.

International audience; This paper deals with piconet topology issues in IEEE 802.15.3 High Rate Wireless Personal Area Network standard. These issues preventing two devices to establish a connection come from the coexistence of two conflicting concepts : ad-hoc networking and centralized coordination. An algorithm for the initialization of the topology of the piconet is proposed. This algorithm leads to a probability higher than 95% of connection success in the whole power emission range defined by the standard.

The aim of this study was to understand the women's motivations and hindrances for choosing and keeping on with breast-feeding.The survey was conducted in a group of 308 women chosen at random at least three months after their delivery. Practitioners and midwives submitted to them a self-questionnaire.The survey showed that breast-feeding was chosen only in 51% of the cases and that the average duration was of two months. Women who breast-fed were more than 35 years old, multiparous, having personal history of breast-feeding and having followed the courses of preparation for the delivery. The fear of mammary disease (22%) and the constraints of availability (50%) seem to influence the women towards an artificial feeding.The reflation of breast feeding should have financial and social incentive measures. The frame of breast feeding women should be improved notably by a better training of health professionals.

Modeling sea clutter of high resolution maritime surveillance radar must provide a validation of algorithms in a perfect well-known context, before comparison with real data. The purpose of the paper is to study modelling of the sea clutter. It considers the temporal evolution of sea clutter for which statistical analysis is carried out. High order statistics are used to solve the problem. It also deals with spatial correlation of sea clutter. >

In internal gas proportional counting, the evaluation of counting losses is important in order to obtain high accuracy measurement results. In this paper, counting losses due to the wall effect not counted and beta particles with very low energy are evaluated by analytical calculations. The calculated and experimental results are compared and a very good agreement is found.

The present study was aimed at identifying surface-membrane molecules involved in the regulation of human B-cell ontogeny. For this purpose, murine monoclonal antibodies (MoAbs) were generated against Pre-Alp, a pre-B acute lymphoblastic leukemia (ALL) cell line, and MoAb R34.34 was selected for further characterization. R34.34 recognized a molecule expressed on normal B-cell precursors (BCP) but not on mature B cells. The antibody also reacted with T lymphocytes, a subpopulation of monocytes from peripheral blood, and a subset of CD34+ cells. Immunoprecipitation analysis indicated that R34.34 recognizes an 80-kD molecular weight antigen. Antibody R34.34 was further found to be directed against an epitope interfering with binding of interleukin-7 (IL-7) to Pre-Alp cells. Expression cloning from a Pre-Alp cDNA library showed that R34.34 antigen is CDw127, the 75- to 80-kD IL-7 receptor. Proliferation of the B-lineage ALL cell lines Reh and Mieliki was inhibited by IL-7, and this effect was specifically reverted by MoAb R34.34. In addition, antibody R34.34 specifically inhibited IL-7-dependent proliferation of normal BCP, Pre-Alp cells, and peripheral T cells. These results imply that both inhibitory and proliferative effects of IL-7 can be mediated through the same receptor on various lineages. R34.34 antibody should be important for the analysis of signal transduction through CDw127.

Growth of human B-cell precursors (BCP) was achieved by plating fetal CD10+ surface-mu (s mu)- cells in liquid medium onto bone marrow- derived fibroblastic stromal cell layers deprived of hematopoietic cells. Proliferation of the fetal BCP was strongly potentiated by the addition of interleukin-7 (IL-7) to the cultures. Cultures included both a stroma-adherent and -nonadherent fraction of lymphoid cells, allowing us to expand the number of input BCP to 13-fold. In the presence of exogenous IL-7, proliferation was dose-dependent relative to the number of stromal cells, demonstrating that soluble IL-7 does not act alone to promote optimal growth. We further showed that the lymphoid cells recovered remain CD10+ sIg- BCP and that most cells expressed the maturation-associated CD20 antigen when IL-7 was added to the cultures. Whereas both freshly isolated CD20- and CD20bright BCP proliferated in the presence of stroma, we observed that high- proliferative capacity CD20dim cells were maintained in the cultures. Finally, CD20dim sorted cells were shown to subsequently acquire high levels of CD20 expression in culture, thus demonstrating a partial maturation sequence. The present culture system thus represents a useful model for studying the regulatory signals in early human B lymphopoiesis.

Differences in the plastic adhesive properties of bone marrow (BM) cells were used to initiate modified stromal layers (MSL) from long-term cultures by removing non-adherent cells shortly (4 to 18 hours) after initial seeding. Following this early modification, adherent cells generated a confluent layer after 21 days of culture. Cellular characteristics of volume and spontaneous fluorescence determined by flow cytometry showed that the MSL included 82% fibroblastic stromal cells, 8% macrophages and 10% myelomonocytic cells. Furthermore, clonogenic assays revealed that the MSL were devoid of hematopoietic progenitor cells. MSL were found to sustain long-term myelopoiesis for at least 7 weeks from exogenously added hematopoietic progenitors isolated from bone marrow (CD34+ cells), thereby demonstrating their functionality. The present experimental model appears of interest for the study of interactions between defined populations of hematopoietic cells and cells of the adherent layer. Of importance, our present modifications of human long-term bone marrow culture are technically simple and do not involve manipulation of the stromal cells.

Purified B cell precursors (BCP) (CD10+ CD19+ surface-membrane (s)Ig-cells) isolated from human fetal bone marrow (BM) were cultured with various cytokines, in the presence or absence of a fibroblastic stromal cell layer derived from adult human BM. We demonstrated that IL-7, IL-3, and stem-cell factor (SCF) participate in inducing low magnitude BCP proliferation in the absence of stroma. Addition of either IL-4, IFN (alpha and gamma), or TGF beta, resulted in significant inhibition of proliferation. Strikingly, BCP proliferated at remarkably higher levels when cultured on BM stromal cells, and this effect was further enhanced by exogenously supplied IL-7. Proliferating cells were mostly CD20+, and included both c mu- and c mu+ cells. Furthermore, BCP proliferated in response to anti CD40 antibody presented by Fc gamma RII-transfected murine fibroblastic Ltk- cells (CD40 system) (Banchereau et al. 1991), demonstrating a functional role for CD40 in B cell ontogeny. However, this effect was shown to require a second signal, which could be specifically provided by IL-3 among a panel of cytokines examined. Finally, although suggestive of BCP maturation, the culture systems examined did not permit the transition to mature B cells (sIgM+ sIgD+).

Purified B cell precursors (BCP) (CD10+ CD19+ surface-membrane (s)Ig- cells) isolated from human fetal bone marrow (BM) were cultured with various cytokines, in the presence or absence of a fibroblastic stromal cell layer derived from adult human BM. We demonstrated that IL-7, IL-3, and stem-cell factor (SCF) participate in inducing low magnitude BCP proliferation in the absence of stroma. Addition of either IL-4, IFN (α and γ), or TGFs, resulted in significant inhibition of proliferation.

The present study describes our efforts to induce the proliferation of human B cell precursors (BCP). Committed BCP (CD10+, sIgM-) isolated from fetal bone marrow (18-25 weeks) were induced to proliferate at low levels in the presence of IL7. IL3 potentiated this effect of IL7 on BCP, while IL4 partially inhibited this proliferation. However, neither of these cytokines allowed the emergence of mature B cells. The growth of BCP was strongly potentiated by the presence of an adherent fibroblastic bone marrow stromal layer devoid of cells of hematopoietic origin. Addition of IL7 to such cocultures further increased BCP proliferation. BCP were shown to proliferate as stroma-adherent and non adherent cells. Total cell numbers expanded during 3 weeks, as much as 8 fold in the presence of IL7 when compared with input BCP numbers. Finally, BCP remained sIgM- in stroma dependent cultures, and only a subpopulation of cells became CD20+ in the presence of IL7. Our present study demonstrates the feasibility of human BCP expansion in vitro. However, the signals required for the transition of BCP to mature B cells remain to be determined.

Using long-term culture techniques, we were able to characterize the different adherent cell elements of the in vitro bone marrow microenvironment by flow cytometry. After 2 weeks of culture, four adherent cell subsets, L, MM, F, and M, were distinguished according to their intrinsic cellular characteristics of volume and spontaneous fluorescence. Using four immunological markers, we identified each population as a hematopoietic lymphocytic group (L), CD45+, VIM2-, CD14-; a hematopoietic myelomonocytic group (MM), CD45+, VIM2+, CD14-; a hematopoietic macrophage group (M), brightly autofluorescent, CD45+, VIM2-, CD14+; and a group of fibroblastoid cells (F) with a very high volume, CD45-, VIM2-, CD14-, and collagen III+. Isolation of the different hematopoietic and nonhematopoietic components of long-term bone marrow culture is thus possible using flow cytometry analysis according to the cell characteristic of volume and spontaneous fluorescence alone.

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Normal human bone marrow stromal cells (BMSC) were isolated from Dexter- type long-term cultures according to their capacity to adhere to plastic and to their lack of hematopoietic antigens. The BMSC displayed a homogeneous appearance and a myofibroblastic phenotype in culture. The stromal cells (SC) were shown to support the proliferation of purified CD34+ hematopoietic progenitors and permitted us to maintain myeloid cells for several weeks in culture. In addition, the BMSC induced the proliferation of purified CD10+ s mu- fetal BM B-cell precursors (BCP). The capacity of the BMSC to induce the proliferation of early myeloid cells was shared by several other human fibroblastic- like cell types. In contrast, the BMSC were far superior to other adherent cells for induction of BCP proliferation. This capacity was largely mediated by endogenously produced interleukin-7 (IL-7), because it could be inhibited by anti-IL-7 antibody. In line with this finding, addition of IL-7 considerably enhanced BCP proliferation in cocultures with skin fibroblasts or synoviocytes. Thus, production of IL-7 appears to be a critical parameter that determines the ability of fibroblastic- like cells to induce BCP proliferation. Taken together, our data show that normal human myofibroblastic BMSC induce the proliferation of both early myeloid and B-lymphoid cells in the absence of accessory hematopoietic cells. The present system should constitute a model to study interactions between native human BM myofibroblastic stroma and various hematopoietic cell subsets.

International audience; L’introduction de ce volume collectif consacré à l’invention fictionnelle au XVIIe siècle en Europe se présente à la fois comme une présentation succincte des contributions originales qui suivent et comme une réflexion d’ordre méthodologique sur ce qu’est la fiction à cette époque. La fiction en prose se définit en effet par sa labilité. Les hésitations terminologiques soulignent assez la difficulté de cerner une production en plein essor, ce d’autant plus qu’auteurs, libraires et traducteurs jouent de la nouveauté pour mieux séduire un lectorat avide de romanesque. Une comparaison de la section de la Bibliothèque française de Charles Sorel consacrée aux fictions en prose avec le Catalogue of the Most vendible Books in England du libraire William London permet d’analyser l’évolution des genres du point de vue des discours descriptifs et prescriptifs qui, à l’époque, tentent de mettre un peu d’ordre dans la librairie et influencent en retour les pratiques de lecture.