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ABSTRACTThe reconstruction of blood velocity in a vessel from contrast-enhanced X-ray CT projections is a complex inverse problem. In this work, we investigate an inversion approach based on the adjoint method with a partial differential equation as constraint. The proper orthogonal decomposition method is used to accelerate the reconstruction with reduced basis for the velocity, the density and the adjoint method. The effectiveness of the reconstruction method is shown with simulated realistic stationary and non-stationary blood flows in a vessel.

X-ray in-line phase contrast imaging relies on the measurement of Fresnel diffraction intensity patterns due to the phase shift and the attenuation induced by the object. The recovery of phase and attenuation from one or several diffraction patterns is a nonlinear ill-posed inverse problem. In this work, we propose supervised learning approaches using mixed scale dense (MS-D) convolutional neural networks to simultaneously retrieve the phase and the attenuation from x-ray phase contrast images. This network architecture uses dilated convolutions to capture features at different image scales and densely connects all feature maps. The long range information in images becomes quickly available, and greater receptive field size can be obtained without losing resolution. This network architecture seems to account for the effect of the Fresnel operator very efficiently. We train the networks using simulated data of objects consisting of either homogeneous components, characterized by a fixed ratio of the induced refractive phase shifts and attenuation, or heterogeneous components, consisting of various materials. We also train the networks in the image domain by applying a simple initial reconstruction using the adjoint of the Fréchet derivative. We compare the results obtained with the MS-D network to reconstructions using U-Net, another popular network architecture, as well as to reconstructions using the contrast transfer function method, a direct phase and attenuation retrieval method based on linearization of the direct problem. The networks are evaluated using simulated noisy data as well as images acquired at NanoMAX (MAX IV, Lund, Sweden). In all cases, large improvements of the reconstruction errors are obtained on simulated data compared to the linearized method. Moreover, on experimental data, the networks improve the reconstruction quantitatively, improving the low-frequency behavior and the resolution.

Purpose: Management of a child’s anxiety early in their treatment is essential in dentistry. Sedative medications are used to overcome increased anxiety from previous appointments and to promote the cooperation of children during treatment. Hydroxyzine is currently prescribed to young patients as part of the first level of conscious sedation. The main objective was to evaluate the professional practice of oral hydroxyzine, when prescribed for children presenting anxiety during dental treatment procedure performed by students and senior practitioners. Methods: A retrospective study of dental records and questionnaires was conducted at the Dental Care Centre of the University Hospital of Rennes, France. Parameters related to the prescription of hydroxyzine in children were evaluated as potential predictors of the dental session success, with adjustments on potential confounders. Results: The therapeutic outcome was very encouraging with 78.3% of success during dental sessions under sedation with oral hydroxyzine. Anxiety levels before the dental procedure and the medication compliance of the child were the main predictors of success. On the other hand, lower age (< 6 years old) and longer treatments (such as pulpotomy) worsened the outcome. Conclusions: Careful analysis of the literature and results of this work showed the safety of hydroxyzine within the maximum dose authorized without adverse effects, compared to other molecules described and commonly used in dentistry. No adverse effects during dental procedure were noted. This allows for minimal sedation with efficiency for the great majority of pediatric treatment. This solution should be the first step in sedation to help practicing clinicians.

High resolution peripheral quantitative CT (HR-pQCT) permits to investigate bone micro-architecture in vivo. While it is a considerable progress over standard CT for this specific application, the spatial resolution remains so far limited for the investigation of bone topology. In this paper, we investigate super resolution techniques to improve 3-D HR-pQCT images via semi-coupled dictionary learning based on the knowledge of high resolution micro-CT images. We propose a method to select the number of atoms and study the impact of patch sizes. To handle the anisotropy of the 3-D bone structure, we propose a 2.5-D strategy learning low and high resolution dictionaries in a semi-coupled way on the three different directions. The results show that this strategy is superior to the application of the method in 2-D. The bone volume fraction is successfully recovered and the estimation of the connectivity is improved in most test samples. The images have a better quality compared with previously studied methods based on total variation (TV) regularization or a combination of TV and a double-well potential. In the future, we expect to further evaluate the method on a larger data set.

New markers are needed to improve diagnosis and to personalize treatments for patients with breast cancer (BC). Receptor-interacting protein of 140 kDa (RIP140) and ligand-dependent corepressor (LCoR), two transcriptional co-regulators of estrogen receptors, strongly interact in BC cells. Although their role in cancer progression has been outlined in the last few years, their function in BC has not been elucidated yet. In this study, we investigated RIP140 and LCoR localization (cytoplasm vsnucleus) in BC samples from a well-characterized cohort of patients (n = 320). RIP140 and LCoR were expressed in more than 80% of tumors, (predominantly in the cytoplasm), and the two markers were highly correlated. Expression of RIP140 and LCoR in the nucleus was negatively correlated with tumor size. Conversely, RIP140 and LCoR cytoplasmic expression strongly correlated with expression of two tumor aggressiveness markers: N-cadherin and CD133 (epithelial mesenchymal transition and cancer stem cell markers, respectively). Finally, high RIP140 nuclear expression was significantly correlated with longer overall survival, whereas high total or cytoplasmic expression of RIP140 was associated with shorter disease-free survival. Our study strongly suggests that the role of RIP140 and LCoR in BC progression could vary according to their prevalent sub-cellular localization, with opposite prognostic values for nuclear and cytoplasmic expression. The involvement in BC progression/invasiveness of cytoplasmic RIP140 could be balanced by the anti-tumor action of nuclear RIP140, thus explaining the previous contradictory findings about its role in BC.

Introduction : Le présent rapport de cas confirme l’hypothèse selon laquelle l’embryogenèse et la croissance maxillo-faciale sont sous l’influence du système nerveux périphérique et notamment du nerf trijumeau (V). Il devient intéressant d’utiliser les stigmates du nerf trijumeau comme référentiel pour analyser tridimensionnellement le volume maxillo-facial et comprendre sa croissance. L’objectif est d’évaluer la validité de l’analyse céphalométrique tridimensionnelle d’essence trigéminale de Treil. Présentation des cas : Le premier cas est un enfant caucasien de sexe féminin atteint du syndrome de Goldenhar. Le deuxième cas est un adulte caucasien de sexe masculin atteint du même syndrome. Dans les deux cas, l’IRM cérébrale montre une atteinte trigéminale unilatérale, homolatérale à l’atteinte faciale. Conclusion : Les résultats de l’étude radiologique de ces cas de syndrome de Goldenhar tendent à prouver le rôle matriciel du nerf trijumeau dans la croissance cranio-faciale. Ces cas mettent en évidence la validité de la conception de la croissance neuro-matricielle de Moss. Ils sont une des justifications anatomo-fonctionnelles de la biométrie tridimensionnelle de Treil d’essence trigéminale.

Les kératokystes ou tumeurs odontogéniques kératokystiques représentent 7 % de tous les kystes odontogéniques et se développent de manière asymptomatique dans la plupart des cas. Bien que l’énucléation soit la solution thérapeutique princeps, d’autres alternatives chirurgicales telles que la marsupialisation ou la décompression s’imposent dans certaines indications. Essentiellement lorsque la tumeur odontogénique kératokystique est de gros volume avec un risque fracturaire associé élevé ou lorsqu’elle présente une inclusion de structures nobles comme le nerf alvéolaire inférieur ou des dents avec comme conséquence un défaut de croissance de l’os alvéolaire. Les auteurs présentent le cas d’une enfant de 9 ans prise en charge pour un volumineux kératokyste secteur 4 incluant la canine et les deux prémolaires. La mise en place d’une décompression associée à un traitement orthodontique multibague a permis de tracter puis de mettre en occlusion sur l’arcade les 3 dents initialement incluses. Avec un recul de 7 ans depuis la première intervention chirurgicale et de 3 ans depuis la fin de traitement orthodontique, cette coordination orthodonticochirurgicale est une réussite aussi bien sur le plan fonctionnel qu’esthétique.

Keratocysts, also known as keratocystic odontogenic tumors (KCOT), make up 7% of all odontogenic cysts and develop asymptomatically in most cases. Enucleation is the benchmark treatment. However, there are surgical alternatives. Marsupialization and decompression are necessary in some cases, mainly when the KCOT is large, thus causing an increased risk of bone fracture, or if it has engulfed important elements such as the inferior alveolar nerve or teeth, consequently causing alveolar bone growth failure. The authors describe the case of a nine-year-old child treated for a large keratocyst situated in sector 4 (lower right jaw), impacting both premolars and the canine (45, 44 and 43). Surgical decompression associated with orthodontic multiband treatment were delivered to pull, and then place the three teeth in occlusion on the dental arch. With seven years hindsight since the first surgical procedure and three years since finishing orthodontic treatment, the cooperation between orthodontists and surgeons can be considered a success, from both the functional and esthetic points of view.

Le modèle céphalométrique à huit points de Treil et les paramètres alvéolo-dentaires permettent déjà une première description de l'architecture maxillo-faciale et de la denture. L'adjonction de six points permet la prise en compte d'un niveau intermédiaire, celui des bases osseuses maxillaires et mandibulaires. Ainsi, le modèle complet à 14 points permet une description complète de l'anatomie cranio-faciale avec trois niveaux d'analyse: la charpente ou l'enveloppe, les bases osseuses et les arcades alvéolo-dentaires. L'étude des corrélations dans les trois sens de l'espace, entre les paramètres des différents niveaux, précise la notion de compensation ; elle permet de comprendre la manière dont une dysmorphie squelettique se répartit entre les différents niveaux. Seules les compensations des dysmorphies verticales sont analysées ici.

Malgré une occlusion antérieure correcte et une classe I canine parfaite, les rapports molaires restent souvent imparfaits, en petite classe II ou en petite classe III : ceci est alors dû à une dysharmonie dento-dentaire maxillo-mandibulaire affectant les secteurs latéraux. L’étude de 62 sujets, traités en multi-attache sans extractions de prémolaires, nous a permis la détermination de la valeur du rapport idéal des diamètres des prémolaires et premières molaires inférieures à leurs homologues supérieures assurant la coïncidence classe I molaireclasse I canine. Cette valeur idéale est 1.062. Les applications thérapeutiques sont discutées, notamment l’influence du choix des extractions, et des solutions sont proposées en cas de dysharmonie avérée.

Une analyse céphalométrique tridimensionnelle complète, à partir d'une saisie scanner, a été élaborée à l'issue d'une longue collaboration entre le Dr Treil et le Service d'Orthopédie Dento-Faciale de Toulouse. Elle permet une lecture parfaite de l'architecture maxillo-faciale globale, basée sur l'identification de quatorze repères liés à l'axe trigéminal, identifiables sans ambiguïté. Cette analyse permet aussi un repérage parfait des positions dentaires linéaires et angulaires, par rapport aux arcades (coordonnées du centre d'inertie, torque et tipping de chaque dent) et un repérage des arcades par rapport à l'architecture maxillo-faciale. L'anatomie dento-maxillo-faciale peut ainsi être parfaitement décrite et reconstruite, avec trois niveaux : la charpente ou enveloppe maxillo-faciale globale, l'étage basi-maxillaire et le niveau alvéolo-dentaire. Cette analyse offre à l'orthodontiste une information dans le sens antéro-postérieur et le sens vertical beaucoup plus riche que la céphalométrie conventionnelle, mais elle ouvre en outre l'accès à la dimension transversale. Les applications sont innombrables tant au niveau de la clinique qu'au niveau de la recherche : cas chirurgico-orthodontiques limites, set-up chirurgical, asymétries faciales, analyse des compensations, définition des objectifs de compensation-décompensation, lecture occlusale et set-up virtuel, étude de l'évolution en anthropologie-primatologie, croissance... La méthode même de description de forme à partir de repères ponctuels s'adapte idéalement aux techniques modernes de morphométrie géométrique avec leurs développements : superposition Procustes, EDMA, TPS, FEM.

Structural Approaches of Polyethylene Environmental Stress-Crack Resistance This work was aimed at understanding and predicting of the long-term mechanical behavior of polyethylene in relation to molecular architecture. An insight into the semi-crystalline microstructure and the chain topology consisting of intercrystalline tie chains and loose folding loops was the main objective of the study. A two-stage crystallization segregation was used for separating the chain species which can easily crystallize by regular folding from those which cannot. The natural draw ratio that develops beyond the yield point proved to be a highly sensitive parameter for probing the chain topology via the crystalline lamella fragmentation and chain unfolding under tensile drawing. Small-angle X-ray scattering provided semi-quantitative evaluation of the stacking disorder of the lamellar microstructure. The data from the three approaches provided correlations with chain architecture in very good agreement with the stress crack resistance dependency. These correlations were discussed in terms of crystallization kinetics and molecular topology. A practical issue of the work is to provide relevant tools for predicting stress cracking resistance.

To assess via a questionnaire the changes in knowledge and prescription habits for systemic fluoride of physicians at maternal and infant protection centres (MIP) and paediatricians in private practice (PPP) in the Brittany region between 2003 and 2014. In both 2003 and 2014, the same seven-question survey was mailed to PPP (110 in 2003 and 101 in 2014) and MIP (61 in 2003 and 71 in 2014). An eighth question was added in 2014 about French guidelines published in 2008 (AFSSAPS guidelines). The overall response rate was significantly higher in 2003 (69.0%) than in 2014 (54.7%). In 2014 systemic fluoride was still considered an effective means of caries prevention (79.8% vs. 98.7% in 2003) and systematic prescription of fluoride supplements was less common (39.4 vs. 87.0% in 2003). When prescribed, systemic fluoride was given after the first 6 months of a child’s life in 2014 (79.8%) instead of within the first month of life (73.5%) in 2003. Paediatricians and MIP physicians in Brittany were significantly less prone to routinely prescribe systemic fluoride in 2014. Certain sources of fluoride were still not well known in 2014. Collaboration and information sharing between dentists and physicians is necessary.

BACKGROUND:We evaluated both estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) status on disseminated tumor cells (DTCs) in the bone marrow of 54 patients with early breast cancer and compared these with the corresponding primary tumor (PT). MATERIALS AND METHODS:Bone marrow aspirates were obtained at the time of first surgery, and ER and HER2 status on DTCs was assessed simultaneously by immunocytochemistry using a triple fluorescence staining method. RESULTS:The median number of DTCs was 13 (range 1-95). The concordance rate between ER status on DTC and PT was 74%. Patients with an ER-positive PT were significantly more likely to have at least one ER-positive DTC (34 out of 42) than patients with an ER-negative PT (6 out of 12; P= .031). Thirty-nine (93%) of the 42 patients with ER-positive PT had at least one ER-negative DTC. The concordance rate between HER2 status on DTC and PT was 52%. The probability of having at least one HER2-positive DTC was not related to the HER2 status of the PT (P= 0.56). Twenty-two (46%) of the 48 patients with a HER2-negative PT had at least one HER2-positive DTC. All the six patients with a HER2-positive PT had at least one HER2-negative DTC. CONCLUSION:Taken together, our study confirms that ER and/or HER2 status may differ between DTC and PT. This discordance could be important for patients lacking ER or HER2 expression on the PT but showing ER-positive or HER2-positive DTC because they might benefit from an endocrine and/or HER2-targeted therapy.

To assess retrospectively the efficacy of computer-assisted intraosseous anaesthesia (CAIO) in children using an anaesthetic solution with a lower concentration of epinephrine (1:400,000). In a retrospective study, CAIO was evaluated in healthy children and adolescents for restorative and endodontic treatments, uncomplicated tooth extractions or scalings using articaine 4 % plus epinephrine 1:400,000. Anaesthesia was performed in children who showed enough compliance (score of 0–3 according to modified behaviour Venham scale). Efficacy, amount of anaesthetic solution as well as need of a complementary injection was assessed. A total of 421 consecutive sessions were performed on 278 patients aged 7.1 ± 2.9 years with 518 teeth involved in the anaesthetic process and analysed process. When teeth to be anaesthetised were considered, the overall success rate was 97.2 %. In most of the cases, only 0.9 mL was needed to achieve anaesthesia. Permanent teeth needed significantly more anaesthetics than primary teeth. Sensitivity of the teeth anaesthetized reappeared in 5.7 % of cases after 30–60 min of treatment. These results suggest that CAIO with 4 % articaine and epinephrine diluted 1:400,000 can be an alternative to usual infiltration techniques or IO with epinephrine at a higher concentration for most of treatments in primary and permanent teeth. Further studies are needed to evaluate its efficacy in permanent teeth in case of endodontic treatment or extraction.

The anisotropy of the main chain conformation of a side-on fixed liquid crystal elastorner on application of a mechanical stress has been measured in the isotropic and nematic phases by small angle neutron scattering. The radii of gyration parallel and perpendicular to the stress field have been determined on elongation and as a function of temperature. A weak anisotropy of the main chain conformation is found only in the nematic phase at sufficiently high values of elongation. A comparison to a theory based on a Landau de Gennes expansion of the free energy for oriented monodomain samples which includes coupling between elastic deformation and nematic strain is made.

A film consisting of an amorphous photo-crosslinkable polymer matrix and a dispersion of microinclusions of a cholesteric polymer was investigated by transmission electron microscopy (TEM). The polymerization procedure of the blend provides a composite with many small nodules of spherical or ellipsoidal shapes, with sizes between 0.4 and 6 μm. The cholesteric stratification is well evidenced in transmission electron microscopy by dark lines due to diffraction contrast. The 3D organization was reconstructed by the observation of successive ultramicrotomed sections. Six types of nodules were distinguished according to the number of defects (foci or disclination lines), among which only three had already been observed and theoretically calculated. The confined geometry inherent in the size of the nodules, close to the cholesteric pitch, is responsible of these unexpected structures. In these conditions, the surface forces are in tight competition with the cholesteric elastic forces.

we report a low frequency mechanical relaxation study of molecular motions near and below glass transition in side chain liquid crystal polymers (SCLCP) in the cholesteric state. The SCLCP was a blend of crosslinked and uncrosslinked materials. Different compositions were studied. These materials exhibit low temperature relaxation processes and a main relaxation connected to the glass transition. Localised motions are responsible for the low temperature processes while the main relaxation exhibits cooperative features and is sensitive to the amount of crosslinked fraction. The relaxation time in the glass transition range when plotted against normalised reciprocal temperature shows that the molecular motions display a fragile character in agreement with the highly cooperative feature and strong physical aging effects. These observations are discussed in the frame of correlated motions involved in the liquid glass transition.

Based on a compressed single embedded fiber composite, constituted with a 7 μm or 49 μm fiber in an epoxy matrix, photoelasticity observables images are calculated. The microbuckling model, first developped by Lee and Harris [21] and then completed by Grandsire-Vinçon [14] (O.N.E.R.A.) is used. From it, it is possible to obtain the principal deformations, their difference as well as the principal directions. In addition to the active layer which contains the fiber microbuckling plane, some additional layers, corresponding to those which are situated above and below the fiber microbuckling plane, have also been taken into account. In the case of T300 fiber (7 μm of diameter), and for an initial undulation of 0.5 μm of amplitude, an oscillation period of 50 or 100 μm, and a global compression taken between 1 and 3 %, the results of the simulation, with or without additional layers and with or without quarter wave plates, show relatively dark images. The contrast is low and the amplitude of the deformations are rather the same as all over images. In the case of the C49 fiber (49 μm of diameter), the contrast is more pronounced and the results of the simulation show significant modifications with the variations of some parameters and are quite in agreement with experiment. In particular, the difference of the principal deformations decrease over a distance similar to the fiber diameter around the latter; we obtain a color alternance when the angle between the polarizer and the fiber axis changes, and finally, the local strain is larger near concave part of the undulation than near the convex one.

Les phénomènes de rupture en mode de traction et de compression dans des composites monofilamentaires carbone/époxydes ont été étudiés par photoélasticité. Les espériences ont été réalisées avec des fibres de carbone de 7 microns de diamètre mais aussi avec des fibres de diamètre plus élevé (49 μm) afin de mieux caractériser le comportement des contraintes à l'interface. Nous avons déterminé la cinétique de rupture. L'intervalle de fragmentation est nettement plus réduit en mode compression que celui obtenu en mode traction. En mode traction: les cas de rupture sans décohésion et avec décohésion ont été mis en évidence et discutés. Le réseau de franges des isocontraintes en cisaillement et les évolutions de l'interface fibre-matrice (longueur de décohésion, longueur de rechargement, stabilité), d'un brin de fibre ont été déterminés. La surface de friction de la zone de décohésion est rapidement insuffisante pour jouer un rôle de transfert de charge lorsque la déformation globale dépasse 3 %. La longueur critique Lcqui correspond à la longueur minimale d'un brin de fibre pouvant être rechargé jusqu'à la rupture, est fortement influencée par la décohésion. En mode compression: l'apparition d'un microflambage de la fibre dû aux conditions thermiques de préparation joue un rôle important, puisque les ruptures de la fibre n'apparaissent pas comme en traction aux défauts de la fibre, mais semblent provenir dans un premier temps des points particuliers engendrés par ce microflambage. Les ruptures interviennent préférentiellement aux ventres de la sinusoïde où la dualité traction-compression est présente. L'interface n'est pas l'objet des plus fortes contraintes en cisaillement.

We have observed birefringent spirals induced by a field in a fingerprint texture of a cholesteric polymer in solution in a nematic low molar weight liquid crystal. This paper describes the conditions of nucleation of these spirals and the part of different parameters which determine their characteristics.

Schimke immuno-osseous dysplasia (SIOD) is a rare, severe, autosomal recessive disorder that results in spondyloepiphyseal dysplasia, renal dysfunction, immunodeficiency, facial dysmorphism and growth failure. Little is known about oral features associated with SIOD. Some of the dental anomalies encountered are specific to SIOD and have only been reported in individuals with SIOD. This paper describes the clinical and radiographic dental manifestations of SIOD in two Caucasian brothers. Both lived to be about 10 years old. After a variety of symptoms were reported, a diagnosis of SIOD was finally made when the brothers were, respectively, 5 and 8 years old. At that time, dental anomalies, such as dyschromia, bulbous crowns, short and thin roots, had not been taken into account to establish the diagnosis. However, knowledge of the dental features characteristic of this disease could have helped make the diagnosis. Although both were caries- and periodontal disease-free, special attention was focused on prevention, including dietary counselling, plaque control, oral hygiene instructions and the use of fluoridated toothpaste. The two patients were followed every 6 months, for over 2 years (until their death), by both a private dentist and a university hospital dentist, which helped them maintain good oral health. Oral hygiene was assessed at each appointment and fissure sealants were placed by the private practitioner on their first permanent molars. This report describes dental anomalies specific to SIOD that could facilitate diagnosis. Clinicians and dentists should work in collaboration to diagnose and treat children with SIOD. These patients require regular and specific dental management because of their fragile health and their characteristic dental anomalies. Ideally, preventive visits should be scheduled every 6 months in addition to curative visits as needed.

The phase retrieval process is a nonlinear ill-posed problem. The Fresnel diffraction patterns obtained with hard x-ray synchrotron beam can be used to retrieve the phase contrast. In this work, we present a convergence comparison of several nonlinear approaches for the phase retrieval problem involving regularizations with sparsity constraints. The phase solution is assumed to have a sparse representation with respect to an orthonormal wavelets basis. One approach uses alternatively a solution of the nonlinear problem based on the Fréchet derivative and a solution of the linear problem in wavelet coordinates with an iterative thresholding. A second method is the one proposed by Ramlau and Teschke which generalizes to a nonlinear problem the classical thresholding algorithm. The algorithms were tested on a 3D Shepp–Logan phantom corrupted by white Gaussian noise. The best simulation results are obtained by the first method for the various noise levels and initializations investigated. The reconstruction errors are significantly decreased with respect to the ones given by the classical linear phase retrieval approaches.

Hormone therapy and anti-ErbB2 therapies are prescribed according to the hormone receptor [estrogen receptor α (ERα)/progesterone receptor] and ErbB2 status of the initial tumor, but it appears that circulating tumor cells (CTCs) and, consequently, the metastatic cells may have a different receptor status. As an attempt to meet the crucial need for identification of the subpopulation of patients that will benefit from more individualized therapies, rapidly evolving therapies should allow a profiling of the tumors and/or of the CTCs. We established a triple fluorescence staining using eight cell lines to visualize the CTCs (cytokeratin detection) and then to define their individual ERα and ErbB2 status. Afterward, we used this method for blood samples from 26 metastatic breast cancer patients. We identified major differences of ERα levels between the cell lines and even within one cell line. For the metastatic patients, we detected and characterized CTCs in 38.5% of the patients with a total of 92 CTCs. We could demonstrate that at least 69.6% of the CTCs exhibit an ERα and/or ErbB2 status different from the status of the primary tumor and that the CTCs from only 30% of the patients had no change of receptor status. Strikingly, heterogeneities of the status, aggregation, and size clearly appear within the CTCs. The data we generated outline the importance of a profiling not only of tumors but also of CTCs to establish individualized treatments. CTCs may then appear as new prognosis and treatment marker for both metastatic and adjuvant breast cancers.

Although estrogens are known to have a deleterious effect on the venous thrombosis risk and a preventive action on the development of arterial atheroma, their effect on platelet function in vivo remains unclear. Here, we demonstrate that a chronic high physiologic level of estradiol (E2) in mice leads to a marked decrease in platelet responsiveness ex vivo and in vivo compared with ovariectomized controls. E2 treatment led to increased bleeding time and a resistance to thromboembolism. Hematopoietic chimera mice harboring a selective deletion of estrogen receptors (ERs) α or β were used to demonstrate that the effects of E2 were exclusively because of hematopoietic ERα. Within ERα the activation function-1 domain was not required for resistance to thromboembolism, as was previously shown for atheroprotection. This domain is mandatory for E2-mediated reproductive function and suggests that this role is controlled independently. Differential proteomics indicated that E2 treatment modulated the expression of platelet proteins including β1 tubulin and a few other proteins that may impact platelet production and activation. Overall, these data demonstrate a previously unrecognized role for E2 in regulating the platelet proteome and platelet function, and point to new potential antithrombotic and vasculoprotective therapeutic strategies.

Although estrogens are known to have a deleterious effect on the venous thrombosis risk and a preventive action on the development of arterial atheroma, their effect on platelet function in vivo remains unclear. Here, we demonstrate that a chronic high physiologic level of estradiol (E2) in mice leads to a marked decrease in platelet responsiveness ex vivo and in vivo compared with ovariectomized controls. E2 treatment led to increased bleeding time and a resistance to thromboembolism. Hematopoietic chimera mice harboring a selective deletion of estrogen receptors (ERs) α or β were used to demonstrate that the effects of E2 were exclusively because of hematopoietic ERα. Within ERα the activation function-1 domain was not required for resistance to thromboembolism, as was previously shown for atheroprotection. This domain is mandatory for E2-mediated reproductive function and suggests that this role is controlled independently. Differential proteomics indicated that E2 treatment modulated the expression of platelet proteins including β1 tubulin and a few other proteins that may impact platelet production and activation. Overall, these data demonstrate a previously unrecognized role for E2 in regulating the platelet proteome and platelet function, and point to new potential antithrombotic and vasculoprotective therapeutic strategies.

Une interrogation sur la réalité du consentement de l’adolescent est proposée. Cette réflexion, de nature éthique, confronte le volet médico-légal du contrat de soins, spécifique lorsqu’il s’agit d’un mineur, avec le volet psychologique si particulier lorsqu’il s’agit d’un adolescent. Comment traitons-nous le mineur adolescent ? Au-delà du questionnement quasi-philosophique sur la relation interhumaine de soins, nous proposons des éléments de réponses très pratiques.

Une interrogation sur la réalité du consentement de l’adolescent est proposée. Cette réflexion, de nature éthique, confronte le volet médico-légal du contrat de soins, spécifique lorsqu’il s’agit d’un mineur, avec le volet psychologique si particulier lorsqu’il s’agit d’un adolescent. Comment traitons-nous le mineur adolescent ? Au-delà du questionnement quasi-philosophique sur la relation interhumaine de soins, nous proposons des éléments de réponses très pratiques.

The eight points cephalometric Treil model and the alveolodental parameters already allows an initial description of the maxillofacial framework and the teeth. Added six points allows taking into consideration an intermediate level: the maxillary and mandibular skeletal basis. So, the 14 points complete model allows a complete craniofacial anatomy description in three analysis levels: the framework or enveloppe, the osseous bases, the alveolodental arch. The correlation study between the 3D parameters at different levels defines the compensation notion. It allows understanding how skeletal disharmony may be distributed among the different levels. Only vertical direction compensations are analysed here. Le mod?le c?phalom?trique ? huit points de Treil et les param?tres alv?olo-dentaires permettent d?j? une premi?re description de l'architecture maxillo-faciale et de la denture. L'adjonction de six points permet la prise en compte d'un niveau interm?diaire, celui des bases osseuses maxillaires et mandibulaires. Ainsi, le mod?le complet ? 14 points permet une description compl?te de l'anatomie cranio-faciale avec trois niveaux d'analyse: la charpente ou l'enveloppe, les bases osseuses et les arcades alv?olo-dentaires. L'?tude des corr?lations dans les trois sens de l'espace, entre les param?tres des diff?rents niveaux, pr?cise la notion de compensation?; elle permet de comprendre la mani?re dont une dysmorphie squelettique se r?partit entre les diff?rents niveaux. Seules les compensations des dysmorphies verticales sont analys?es ici.

A 3D cephalometric analysis method from scanner acquisition has been developed thanks to a long collaboration between Dr Treil and the Department of Orthodontics in Toulouse III University. It allows a perfect knowledge of maxillo-facial architecture using fourteen landmarks related to the neuromatricial axis of facial growth. These landmarks can be identified without ambiguity. The marking of each tooth relative to dental arches (gravity centre coordinates and torque and tipping of each tooth), and the location of arches relative to maxillo-facial frame are given by the analysis. Description and reconstruction of dental and maxillo-facial anatomy are possible with three levels: maxillo-facial frame, maxillar and mandibular bases and dentoalveolar level. The method not only gives more precise information than conventional cephalometrics in anteroposterior and vertical directions, but it allows transversal analysis and asymmetry measurement. Applications are numerous in research as well as in clinical medicine: analyses of cases border line surgery, surgical set-up, facial asymmetry, analysis of dentoalveolar compensations, definition of therapeutic aims, occlusal analysis and set-up, study of evolution in anthropology-primatology, study of growth etc. This method of description using a pattern of landmarks is perfectly adapted to the last developments of modern research techniques: morphometric geometry with Procustes superimpositions, EDMA, TPS, FEM. Une analyse c?phalom?trique tridimensionnelle compl?te, ? partir d'une saisie scanner, a ?t? ?labor?e ? l'issue d'une longue collaboration entre le Dr Treil et le Service d'Orthop?die Dento-Faciale de Toulouse. Elle permet une lecture parfaite de l'architecture maxillo-faciale globale, bas?e sur l'identification de quatorze rep?res li?s ? l'axe trig?minal, identifiables sans ambigu?t?. Cette analyse permet aussi un rep?rage parfait des positions dentaires lin?aires et angulaires, par rapport aux arcades (coordonn?es du centre d'inertie, torque et tipping de chaque dent) et un rep?rage des arcades par rapport ? l'architecture maxillo-faciale. L'anatomie dento-maxillo-faciale peut ainsi ?tre parfaitement d?crite et reconstruite, avec trois niveaux?: la charpente ou enveloppe maxillo-faciale globale, l'?tage basi-maxillaire et le niveau alv?olo-dentaire. Cette analyse offre ? l'orthodontiste une information dans le sens ant?ro-post?rieur et le sens vertical beaucoup plus riche que la c?phalom?trie conventionnelle, mais elle ouvre en outre l'acc?s ? la dimension transversale. Les applications sont innombrables tant au niveau de la clinique qu'au niveau de la recherche?: cas chirurgico-orthodontiques limites, set-up chirurgical, asym?tries faciales, analyse des compensations, d?finition des objectifs de compensation-d?compensation, lecture occlusale et set-up virtuel, ?tude de l'?volution en anthropologie-primatologie, croissance... La m?thode m?me de description de forme ? partir de rep?res ponctuels s'adapte id?alement aux techniques modernes de morphom?trie g?om?trique avec leurs d?veloppements?: superposition Procustes, EDMA, TPS, FEM.

The hot‐compaction of polyoxymethylene powders in the solid state, otherwise pressure‐assisted sintering, is studied as an alternative way to the melt‐compression or injection molding processes. A native powder issued from suspension polymerization has been used, together with powders obtained from grinding of melt‐extruded pellets. The experimental conditions were optimized with regard to temperature, pressure, and time. Temperature is the most sensitive parameter of the process. Sintering at temperature close to the onset of the melting range turned out to be necessary for an efficient welding of the powder particles, as judged from mechanical properties. Despite a strong loss of ductility, the sintered samples have been easily machined out into strips for mechanical testing. A significant increase in crystallinity is observed for the sintered samples, as compared with the compression‐molded ones, accompanied with a nearly twofold increase of the Young's modulus. Scanning electron microscopy revealed that rupture of the sintered samples involves both inter‐ and intra‐granular fracture. Welding of the crystallites via molecular diffusion at the particle interface is suggested to be the mechanism of sintering. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1274–1284, 2006

Butyl and pentyl ether derivatives of (2-hydroxypropyl) cellulose (HPC) and butyl/pentyl mixed ethers of HPC (BPPC) with different alkyl compositions were prepared in nonaqueous solution and their thermotropic cholesteric properties examined. The temperature dependence and the composition dependence of the optical pitch, nP, were then determined for all of the ether derivatives. The molecular conformation and chirality of BPPC appeared to be to be variably smooth with the side chain composition of the polymer. The response rate of cholesteric configurational change of the thermotropic mesophases arising from a temperature jump from 45  to 75 °C, was also determined. The transformation of the cholesteric mesophase formed by an equimolar ether derivative (BP-50) was faster than that of the cholesteric one formed by a single-alkyl (pentyl) ether derivative (BP-0). This seemed to be a general result reflecting a pseudo-copolymer effect of cellulose derivatives on the properties of their thermotropic cholesteric mesophases.Butyl and pentyl ether derivatives of (2-hydroxypropyl) cellulose (HPC) and butyl/pentyl mixed ethers of HPC (BPPC) with different alkyl compositions were prepared in nonaqueous solution and their thermotropic cholesteric properties examined. The temperature dependence and the composition dependence of the optical pitch, nP, were then determined for all of the ether derivatives. The molecular conformation and chirality of BPPC appeared to be to be variably smooth with the side chain composition of the polymer. The response rate of cholesteric configurational change of the thermotropic mesophases arising from a temperature jump from 45  to 75 °C, was also determined. The transformation of the cholesteric mesophase formed by an equimolar ether derivative (BP-50) was faster than that of the cholesteric one formed by a single-alkyl (pentyl) ether derivative (BP-0). This seemed to be a general result reflecting a pseudo-copolymer effect of cellulose derivatives on the properties of their thermotropic cholesteric mesophases.

We present the optimization of a sterilization process with a N2 flowing afterglow post-discharge. First we study the inactivation of bacteria (E. coli) submitted to the post-discharge, and discuss the mechanisms of bacteria inactivation. Then we evaluate the volume repartition of the active species (N atoms produced by plasma discharge) in the chamber of treatment.

We present the optimization of a sterilization process with a N2flowing afterglow post-discharge. First we study the inactivation of bacteria (E. coli) submitted to the post-discharge, and discuss the mechanisms of bacteria inactivation. Then we evaluate the volume repartition of the active species (N atoms produced by plasma discharge) in the chamber of treatment.

Tout en se demandant d'abord si la carie dentaire est encore aujourd'hui un problème de santé publique dans nos pays, l'auteur ajoute quelques questions sur la nécessité des études épidémiologiques, et l'identification des sujets à risque ainsi que les méthodes de sa réalisation.

Tout en se demandant d'abord si la carie dentaire est encore aujourd'hui un problème de santé publique dans nos pays, l'auteur ajoute quelques questions sur la nécessité des études épidémiologiques, et l'identification des sujets à risque ainsi que les méthodes de sa réalisation.Vient ensuite l'enumeration des principaux facteurs de l'évaluation du risque carieux : statut socio-économique, antécédents et traitements médicaux, contrôle de plaque, habitudes alimentaires, utilisation du fluor, facteurs salivaires, critères cliniques.Tout en précisant leur intérêt, les tests et leur technique sont alors présentés.

Recently, plasmas have been largely studied to develop a new cold and safe sterilization process. The plasma efficiency on bacteria destruction has been proved at low or near atmospheric pressure. In our investigation we used a N2-O2post discharge at low pressure, where the experimental conditions allowing the optimal production of active species have been determined: 100 Watt, 1 Ln.min−1, 5 Torr. By exposing E. colito these plasma conditions, it is demonstrated a synergy of N and O active atoms on substrate temperature: a reduction of 6 log was achieved after a treatment time of 20 minutes at 80 °C and of 12 log after 5 minutes at 120 °C.

Recently, plasmas have been largely studied to develop a new cold and safe sterilization process. The plasma efficiency on bacteria destruction has been proved at low or near atmospheric pressure. In our investigation we used a N$_{2}$-O$_{2}$ post discharge at low pressure, where the experimental conditions allowing the optimal production of active species have been determined: 100 Watt, 1 L$_{\rm n}$.min$^{-1}$, 5 Torr. By exposing E. coli to these plasma conditions, it is demonstrated a synergy of N and O active atoms on substrate temperature: a reduction of 6 log was achieved after a treatment time of 20 minutes at 80 °C and of 12 log after 5 minutes at 120 °C.

We showed in a previous study that prenylated proteins play a role in estradiol stimulation of proliferation. However, these proteins antagonize the ability of estrogen receptor (ER) α to stimulate estrogen response element (ERE)-dependent transcriptional activity, potentially through the formation of a co-regulator complex. The present study investigates, in further detail, how prenylated proteins modulate the transcriptional activities mediated by ERα and by ERβ. The ERE-β-globin-Luc-SV-Neo plasmid was either stably transfected into MCF-7 cells or HeLa cells (MELN cells and HELN cells, respectively) or transiently transfected into MCF-7 cells using polyethylenimine. Cells deprived of estradiol were analyzed for ERE-dependent luciferase activity 16 hours after estradiol stimulation and treatment with FTI-277 (a farnesyltransferase inhibitor) or with GGTI-298 (a geranylgeranyltransferase I inhibitor). In HELN cells, the effect of prenyltransferase inhibitors on luciferase activity was compared after transient transfection of plasmids coding either the full-length ERα, the full-length ERβ, the AF-1-deleted ERα or the AF-2-deleted ERα. The presence of ERα was then detected by immunocytochemistry in either the nuclei or the cytoplasms of MCF-7 cells. Finally, Clostridium botulinumC3 exoenzyme treatment was used to determine the involvement of Rho proteins in ERE-dependent luciferase activity. FTI-277 and GGTI-298 only stimulate ERE-dependent luciferase activity in stably transfected MCF-7 cells. They stimulate both ERα-mediated and ERβ-mediated ERE-dependent luciferase activity in HELN cells, in the presence of and in the absence of estradiol. The roles of both AF-1 and AF-2 are significant in this effect. Nuclear ERα is decreased in the presence of prenyltransferase inhibitors in MCF-7 cells, again in the presence of and in the absence of estradiol. By contrast, cytoplasmic ERα is mainly decreased after treatment with FTI-277, in the presence of and in the absence of estradiol. The involvement of Rho proteins in ERE-dependent luciferase activity in MELN cells is clearly established. Together, these results demonstrate that prenylated proteins (at least RhoA, RhoB and/or RhoC) antagonize the ability of ERα and ERβ to stimulate ERE-dependent transcriptional activity, potentially acting through both AF-1 and AF-2 transcriptional activities.

Cette étude a eu pour objectif d’évaluer par culture la composition de la flore associée aux péricoronarites des troisièmes molaires mandibulaires et d’étudier sa sensibilité aux antibiotiques le plus souvent prescrits en France. Résultats : la flore isolée était hétérogène, le plus souvent polymicrobienne et mixte aérobie/anaérobie. La flore anaérobie était prédominante dans la plupart des cas. Les anaérobies stricts ont été retrouvés dans 53 des 61 échantillons. Les bactéries le plus souvent isolées ont été les streptocoques viridans (58/61), puis des genres anaérobies (Prevotella, Veillonella) ou à croissance préférentielle en anaérobie (Actinomyces, Capnocytophaga). L’amoxicilline est l’antibiotique le plus actif sur la flore totale et notamment les germes aérobies, mais peut favoriser la sélection de microorganismes résistants, en particulier ceux producteurs de bêtalactamases. Le métronidazole seul ou en association à la spiramycine a été le plus efficace sur les bactéries anaérobies strictes et le moins agressif pour la flore normale de la cavité buccale. Son utilisation est intéressante dans les cas de péricoronarites avec une flore mixte aérobie/anaérobie bien documentée. (Med Buccale Chir Buccale 2004; 10: 11-20)

Cette étude a eu pour objectif d’évaluer par culture la composition de la flore associée aux péricoronarites des troisièmes molaires mandibulaires et d’étudier sa sensibilité aux antibiotiques le plus souvent prescrits en France. Résultats : la flore isolée était hétérogène, le plus souvent polymicrobienne et mixte aérobie/anaérobie. La flore anaérobie était prédominante dans la plupart des cas. Les anaérobies stricts ont été retrouvés dans 53 des 61 échantillons. Les bactéries le plus souvent isolées ont été les streptocoques viridans (58/61), puis des genres anaérobies (Prevotella, Veillonella) ou à croissance préférentielle en anaérobie (Actinomyces, Capnocytophaga). L’amoxicilline est l’antibiotique le plus actif sur la flore totale et notamment les germes aérobies, mais peut favoriser la sélection de microorganismes résistants, en particulier ceux producteurs de bêtalactamases. Le métronidazole seul ou en association à la spiramycine a été le plus efficace sur les bactéries anaérobies strictes et le moins agressif pour la flore normale de la cavité buccale. Son utilisation est intéressante dans les cas de péricoronarites avec une flore mixte aérobie/anaérobie bien documentée. (Med Buccale Chir Buccale 2004; 10: 11-20)

This work assessed the polymicrobial flora of mandibular third molar pericoronitis. Obligate anaerobes were found in almost all cases (32 of 35). Amoxicillin and pristinamycin were the most effective against the flora, particularly aerobic organisms. Metronidazole alone or combined with spiramycin was the most effective drug against obligate anaerobes.

ABSTRACTThis work assessed the polymicrobial flora of mandibular third molar pericoronitis. Obligate anaerobes were found in almost all cases (32 of 35). Amoxicillin and pristinamycin were the most effective against the flora, particularly aerobic organisms. Metronidazole alone or combined with spiramycin was the most effective drug against obligate anaerobes.

The central involvement of estrogen in the development of the mammary gland and in the genesis of breast cancer has lent impetus to studies of the links between estrogen action and the cell cycle machinery. Recent studies of the estrogenic regulation of molecules with known roles in the control of G1/S phase progression have resulted in significant advances in understanding these links. Estrogens independently regulate the expression and function of c-Myc and cyclin D1 and the induction of either c-Myc or cyclin D1 is sufficient to recapitulate the effects of estrogen on cell cycle progression. These pathways converge at the activation of cyclin E-Cdk2 complexes. The active cyclin E-Cdk2 complexes are depleted of the cyclin dependent kinase (CDK) inhibitor p21(WAF1/CIP1) because of estrogen-mediated inhibition of nascent p21(WAF1/CIP1). Insulin and estrogen synergistically stimulate cell cycle progression, and the ability of estrogen to antagonize an insulin-induced increase in p21(WAF1/CIP1) gene expression appears to underlie this effect. Antiestrogen treatment of MCF-7 cells leads to an acute decrease of c-Myc expression, a subsequent decline in cyclin D1, and ultimately arrest of cells in a state with features characteristic of quiescence. An antisense-mediated decrease in c-Myc expression results in decreased cyclin D1 expression and inhibition of DNA synthesis, mimicking the effects of antiestrogen treatment and emphasizing the importance of c-Myc as an estrogen/antiestrogen target. These data identify c-Myc, cyclin D1, p21(WAF1/CIP1) and cyclin E-Cdk2 as central components of estrogen regulation of cell cycle progression and hence as potential downstream targets that contribute to the role of estrogen in oncogenesis.

Objectives.The purpose of this study was to evaluate the predominant flora associated with pericoronitis in third molars and to investigate the presence of β-lactamase-producing strains. Study design.The third molars in 26 adults were evaluated by cultures with nonselective media and with selective media containing amoxicillin, pristinamycin, spiramycin, metronidazole, and spiramycin plus metronidazole. Results.In the majority of cases (19/26), the flora found in an anaerobic atmosphere predominated. Obligate anaerobes were present in 21 of the 26 samples. The bacteria most commonly detected were α-hemolytic streptococci (26/26) and the genera Prevotella(15/26), Veillonella(15/26), Bacteroides(9/26), and Capnocytophaga(9/26). Amoxicillin and pristinamycin were the most active in reducing the anaerobic cultivable counts. β-Lactamase-producing strains were detected in 9 samples and were mostly bacteria of the genera Prevotella, Staphylococcus,and Bacteroides. Conclusion.These results highlight (1) the diversity of the microflora associated with pericoronitis and the importance of the anaerobic flora and (2) the existence of selection pressure related to the use of β-lactams that may culminate in failure of prescribed penicillins. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2003;95:655-9)

Background:Giving the immunosuppressive drug tacrolimus (FK506) to liver transplant patients has helped to considerably reduce oral side effects such as gingival hyperplasia. Patients taking cyclosporin who suffer from gingival hyperplasia are often switched to tacrolimus. Methods:We present here a pediatric liver transplantation case study. The patient has been followed for 5.5 years. She developed oral lesions that resulted in the immunosuppressive therapy being changed from tacrolimus to cyclosporin. In clinical terms, the atypical pathology consisted of hyperpigmented patches on the gingival margin, the internal surfaces of the cheeks, and the intraoral surfaces of the lips. When located on the lips, the hyperpigmented patches were associated with pruriginous and edematous lesions. Results:Optical and electronic microscopic examinations of a gingival tissue sample revealed the presence of melanin incontinence and lichenoid lesions with degenerated keratinocytes and a mild infiltrate of lymphocytes. This points to a chronic graft‐versushost disease (cGvHD)‐like syndrome linked to tacrolimus. This diagnosis was given further credence by improvement in the lesions following the switch to cyclosporin. Conclusion:To our knowledge, this is the first reported case of tacrolimus‐associated chronic GvHDlike syndrome occurring in the oral mucosa.J Periodontol 2003;74:552‐556.

Les troisièmes molaires peuvent présenter au cours de leur éruption des manifestations inflammatoires locales appelées péricoronarites. Dans les formes aiguës, des signes régionaux et généraux peuvent y être associés (fièvre, adénopathies, trismus) ainsi que des complications éventuelles de type cellulite par diffusion de l'infection dans les espaces anatomiques de voisinage. Une antibiothérapie est alors justifiée, associée ou non à un geste chirurgical. L'amoxicilline et l’association spiramycine-métronidazole sont les antibiotiques les plus utilisés par les opérateurs en France. L’objectif de ce travail a été d’évaluer ces antibiotiques, dans le cadre d’une étude clinique multicentrique dite de test d’équivalence en formation unilatérale (ou test de « non infériorité »), sur une population de 322 adultes (âge moyen 25,18 ± 7,15 ans). Un succès clinique a été constaté dans respectivement 84,8 % (amoxicilline) et 89,2 % (spiramycine-métronidazole) des cas. Il n’y a pas de différence statistiquement significative entre ces deux groupes. Des effets indésirables ont été constatés chez 25 (amoxicilline) et 26 (spiramycine-métronidazole) patients. Les résultats cliniques obtenus dans les deux groupes sont très satisfaisants et comparables statistiquement. Compte-tenu de l’analyse statistique utilisée, il peut être conclu à la légitimité de l’association spiramycinemétronidazole lors de traitement en première intention par antibiotiques des péricoronarites, au même titre que l’amoxicilline. (Med Buccale Chir Buccale 2003 ; 9 : 159-65)