Bcl9/Bcl9l are critical for Wnt-mediated regulation of stem cell traits in colon epithelium and adenocarcinomas.

Canonical Wnt signaling plays a critical role in stem cell maintenance in epithelial homeostasis and carcinogenesis. Here, we show that in the mouse this role is critically mediated by Bcl9/Bcl9l, the mammalian homologues of Legless, which in Drosophila is required for Armadillo/beta-catenin signaling. Conditional ablation of Bcl9/Bcl9l in the intestinal epithelium, where the essential role of Wnt signaling in epithelial homeostasis and stem cell maintenance is well documented, resulted in decreased expression of intestinal stem cell markers and impaired regeneration of ulcerated colon epithelium. Adenocarcinomas with aberrant Wnt signaling arose with similar incidence in wild-type and mutant mice. However, transcriptional profiles were vastly different: Whereas wild-type tumors displayed characteristics of epithelial-mesenchymal transition (EMT) and stem cell-like properties, these properties were largely abrogated in mutant tumors. These findings reveal an essential role for Bcl9/Bcl9l in regulating a subset of Wnt target genes involved in controlling EMT and stem cell-related features and suggest that targeting the Bcl9/Bcl9l arm of Wnt signaling in Wnt-activated cancers might attenuate these traits, which are associated with tumor invasion, metastasis, and resistance to therapy.

Prédiction des durées de séjour en réadaptation en fonction du statut fonctionnel. [Usefulness of functional status to predict length of stay in rehabilitation.]

Objectif : En Suisse, la réadaptation est financée en¦partie par l'assureur qui fixe préalablement à l'admission¦un nombre de jours (durée garantie) qu'il s'engage¦à rembourser. Lorsqu'une durée garantie est trop courte,¦une demande de prolongation est nécessaire, induisant¦des démarches administratives. Les objectifs de cette¦étude étaient a) d'étudier le lien entre durées garanties¦et caractéristiques du patient ; b) d'estimer les coûts¦liés aux demandes de prolongation ; c) d'évaluer¦l'impact de l'introduction d'un modèle d'attribution de¦durée garantie basé sur l'état fonctionnel du patient.¦Méthodes : Les corrélations entre état fonctionnel,¦durée effective et durée garantie ont été testées sur¦208 séjours représentatifs. Des durées garanties fictives¦ont été calculées à partir de la médiane de durée de¦séjour de 2 335 patients, groupés selon leur niveau¦fonctionnel (score des activités de base de la vie quotidienne¦(BAVQ) 0-1 vs 2-4 vs 5-6), puis comparées aux¦durées de séjour effectives et garanties.¦Résultats : L'état fonctionnel du patient n'est pas¦corrélé à la durée garantie, et 69 % des séjours nécessitent¦au moins une demande de prolongation, représentant¦2,6 équivalents temps plein en temps administratif¦projeté sur le canton. L'application du modèle proposé¦réduirait de 28 % les demandes de prolongation, et¦n'augmenterait que marginalement la proportion de¦jours garantis en surplus (11,2 % contre 6,5 % actuellement).¦Conclusion : L'utilisation systématique d'un modèle¦d'attribution de durées garanties basées sur l'état¦fonctionnel du patient permettrait de réduire sensiblement¦les coûts administratifs liés aux demandes de¦prolongation, sans entraîner de risque accru d'une augmentation¦de la durée de séjour.

Functional analysis of the post-transcriptional regulator RsmA reveals a novel RNA-binding site.

The RsmA family of RNA-binding proteins are global post-transcriptional regulators that mediate extensive changes in gene expression in bacteria. They bind to, and affect the translation rate of target mRNAs, a function that is further modulated by one or more, small, untranslated competitive regulatory RNAs. To gain new insights into the nature of this protein/RNA interaction, we used X-ray crystallography to solve the structure of the Yersinia enterocolitica RsmA homologue. RsmA consists of a dimeric beta barrel from which two alpha helices are projected. From structure-based alignments of the RsmA protein family from diverse bacteria, we identified key amino acid residues likely to be involved in RNA-binding. Site-specific mutagenesis revealed that arginine at position 44, located at the N terminus of the alpha helix is essential for biological activity in vivo and RNA-binding in vitro. Mutation of this site affects swarming motility, exoenzyme and secondary metabolite production in the human pathogen Pseudomonas aeruginosa, carbon metabolism in Escherichia coli, and hydrogen cyanide production in the plant beneficial strain Pseudomonas fluorescens CHA0. R44A mutants are also unable to interact with the small untranslated RNA, RsmZ. Thus, although possessing a motif similar to the KH domain of some eukaryotic RNA-binding proteins, RsmA differs substantially and incorporates a novel class of RNA-binding site.

Functional analysis and structural modeling of human APOBEC3G reveal the role of evolutionarily conserved elements in the inhibition of human immunodeficiency virus type 1 infection and Alu transposition.

Retroelements are important evolutionary forces but can be deleterious if left uncontrolled. Members of the human APOBEC3 family of cytidine deaminases can inhibit a wide range of endogenous, as well as exogenous, retroelements. These enzymes are structurally organized in one or two domains comprising a zinc-coordinating motif. APOBEC3G contains two such domains, only the C terminal of which is endowed with editing activity, while its N-terminal counterpart binds RNA, promotes homo-oligomerization, and is necessary for packaging into human immunodeficiency virus type 1 (HIV-1) virions. Here, we performed a large-scale mutagenesis-based analysis of the APOBEC3G N terminus, testing mutants for (i) inhibition of vif-defective HIV-1 infection and Alu retrotransposition, (ii) RNA binding, and (iii) oligomerization. Furthermore, in the absence of structural information on this domain, we used homology modeling to examine the positions of functionally important residues and of residues found to be under positive selection by phylogenetic analyses of primate APOBEC3G genes. Our results reveal the importance of a predicted RNA binding dimerization interface both for packaging into HIV-1 virions and inhibition of both HIV-1 infection and Alu transposition. We further found that the HIV-1-blocking activity of APOBEC3G N-terminal mutants defective for packaging can be almost entirely rescued if their virion incorporation is forced by fusion with Vpr, indicating that the corresponding region of APOBEC3G plays little role in other aspects of its action against this pathogen. Interestingly, residues forming the APOBEC3G dimer interface are highly conserved, contrasting with the rapid evolution of two neighboring surface-exposed amino acid patches, one targeted by the Vif protein of primate lentiviruses and the other of yet-undefined function.

Environment-dependent microevolution in a Mediterranean pine (Pinus pinaster Aiton).

BACKGROUND: A central question for understanding the evolutionary responses of plant species to rapidly changing environments is the assessment of their potential for short-term (in one or a few generations) genetic change. In our study, we consider the case of Pinus pinaster Aiton (maritime pine), a widespread Mediterranean tree, and (i) test, under different experimental conditions (growth chamber and semi-natural), whether higher recruitment in the wild from the most successful mothers is due to better performance of their offspring; and (ii) evaluate genetic change in quantitative traits across generations at two different life stages (mature trees and seedlings) that are known to be under strong selection pressure in forest trees. RESULTS: Genetic control was high for most traits (h2 = 0.137-0.876) under the milder conditions of the growth chamber, but only for ontogenetic change (0.276), total height (0.415) and survival (0.719) under the more stressful semi-natural conditions. Significant phenotypic selection gradients were found in mature trees for traits related to seed quality (germination rate and number of empty seeds). Moreover, female relative reproductive success was significantly correlated with offspring performance for specific leaf area (SLA) in the growth chamber experiment, and stem mass fraction (SMF) in the experiment under semi-natural conditions, two adaptive traits related to abiotic stress-response in pines. Selection gradients based on genetic covariance of seedling traits and responses to selection at this stage involved traits related to biomass allocation (SMF) and growth (as decomposed by a Gompertz model) or delayed ontogenetic change, depending also on the testing environment. CONCLUSIONS: Despite the evidence of microevolutionary change in adaptive traits in maritime pine, directional or disruptive changes are difficult to predict due to variable selection at different life stages and environments. At mature-tree stages, higher female effective reproductive success can be explained by differences in their production of offspring (due to seed quality) and, to a lesser extent, by seemingly better adapted seedlings. Selection gradients and responses to selection for seedlings also differed across experimental conditions. The distinct processes involved at the two life stages (mature trees or seedlings) together with environment-specific responses advice caution when predicting likely evolutionary responses to environmental change in Mediterranean forest trees.

Novel loci for adiponectin levels and their influence on type 2 diabetes and metabolic traits: a multi-ethnic meta-analysis of 45,891 individuals.

Circulating levels of adiponectin, a hormone produced predominantly by adipocytes, are highly heritable and are inversely associated with type 2 diabetes mellitus (T2D) and other metabolic traits. We conducted a meta-analysis of genome-wide association studies in 39,883 individuals of European ancestry to identify genes associated with metabolic disease. We identified 8 novel loci associated with adiponectin levels and confirmed 2 previously reported loci (P = 4.5×10(-8)-1.2×10(-43)). Using a novel method to combine data across ethnicities (N = 4,232 African Americans, N = 1,776 Asians, and N = 29,347 Europeans), we identified two additional novel loci. Expression analyses of 436 human adipocyte samples revealed that mRNA levels of 18 genes at candidate regions were associated with adiponectin concentrations after accounting for multiple testing (p<3×10(-4)). We next developed a multi-SNP genotypic risk score to test the association of adiponectin decreasing risk alleles on metabolic traits and diseases using consortia-level meta-analytic data. This risk score was associated with increased risk of T2D (p = 4.3×10(-3), n = 22,044), increased triglycerides (p = 2.6×10(-14), n = 93,440), increased waist-to-hip ratio (p = 1.8×10(-5), n = 77,167), increased glucose two hours post oral glucose tolerance testing (p = 4.4×10(-3), n = 15,234), increased fasting insulin (p = 0.015, n = 48,238), but with lower in HDL-cholesterol concentrations (p = 4.5×10(-13), n = 96,748) and decreased BMI (p = 1.4×10(-4), n = 121,335). These findings identify novel genetic determinants of adiponectin levels, which, taken together, influence risk of T2D and markers of insulin resistance.

D-JNKi, a peptide inhibitor of c-Jun N-terminal kinase, promotes functional recovery after transient focal cerebral ischemia in rats

The c-Jun-N-terminal kinase (JNK) pathway has been shown to play an important role in excitotoxic neuronal death and several studies have demonstrated a neuroprotective effect of D-JNKi, a peptide inhibitor of JNK, in various models of cerebral ischemia. We have now investigated the effect of D-JNKi in a model of transient focal cerebral ischemia (90 min) induced by middle cerebral artery occlusion (MCAo) in adult male rats. D-JNKi (0.1 mg/kg), significantly decreased the volume of infarct, 3 days after cerebral ischemia. Sensorimotor and cognitive deficits were then evaluated over a period of 6 or 10 days after ischemia and infarct volumes were measured after behavioral testing. In behavioral studies, D-JNKi improved the general state of the animals as demonstrated by the attenuation of body weight loss and improvement in neurological score, as compared with animals receiving the vehicle. Moreover, D-JNKi decreased sensorimotor deficits in the adhesive removal test and improved cognitive function in the object recognition test. In contrast, D-JNKi did not significantly affect the infarct volume at day 6 and at day 10. This study shows that D-JNKi can improve functional recovery after transient focal cerebral ischemia in the rat and therefore supports the use of this molecule as a potential therapy for stroke.

Validation of the French version of the Hierarchical Personality Inventory for Children (HiPIC): Influence of gender and age on personality traits from 8 to 12 years

The study was designed to investigate the psychometric properties of the French version and the cross-language replicability of the Hierarchical Personality Inventory for Children (HiPIC). The HiPIC is an instrument aimed at assessing the five dimensions of the Five-Factor Model for Children. Subjects were 552 children aged between 8 and 12 years, rated by one or both parents. At the domain level, reliability ranged from .83 to .93 and at the facet level, reliability ranged from .69 to .89. Differences between genders were congruent with those found in the Dutch sample. Girls scored higher on Benevolence and Conscientiousness. Age was negatively correlated with Extraversion and Imagination. For girls, we also observed a decrease of Emotional Stability. A series of exploratory factor analyses confirmed the overall five-factor structure for girls and boys. Targeted factor analyses and congruence coefficients revealed high cross-language replicability at the domain and at the facet levels. The results showed that the French version of the HiPIC is a reliable and valid instrument for assessing personality with children and has a particularly high cross-language replicability.

Adjuvant or radical fractionated stereotactic radiotherapy for patients with pituitary functional and nonfunctional macroadenoma.

Purpose: To evaluate the efficacy and toxicity of stereotactic fractionated radiotherapy (SFRT) for patients with pituitary macroadenoma (PMA).Methods and Materials: Between March 2000 and March 2009, 27 patients (male to female ratio, 1.25) with PMA underwent SFRT (median dose, 50.4 Gy). Mean age of the patients was 56.5 years (range, 20.3 - 77.4). In all but one patient, SFRT was administered for salvage treatment after surgical resection (transphenoidal resection in 23, transphenoidal resection followed by craniotomy in 2 and multiple transphenoidal resections in another patient). In 10 (37%) patients, the PMAs were functional (3 ACTH-secreting, 3 prolactinomas, 2 growth hormone-secreting and 2 multiple hormone-secretion). Three (11.1%) and 9 (33.3%) patients had PMA abutting and compressing the optic chiasm, respectively. Mean tumor volume was 2.9 +/- 4.6 cm(3). Eighteen (66.7%) patients had hypopituitarism prior to SFRT. The mean follow-up period after SFRT was 72.4 +/- 37.2 months.Results: Tumor size decreased for 6 (22.2%) patients and remained unchanged for 19 (70.4%) other patients. Two (7.4%) patients had tumor growth inside the prescribed treatment volume. The estimated 5-year tumor growth control was 95.5% after SFRT. Biochemical remission occurred in 3 (30%) patients with functional PMA. Two patients with normal anterior pituitary function before SFRT developed new deficits 25 and 65 months after treatment. The 5-year survival without new anterior pituitary deficit was thus 95.8%. Five patients with visual field defect had improved visual function and 1 patient with no visual defect prior to SFRT, but an optic chiasm abutting tumor, had a decline in visual function. The estimated 5-year vision and pituitary function preservation rates were 93.2% and 95.8%, respectively.Conclusions: SFRT is a safe and effective treatment for patients with PMA, although longer follow-up is needed to evaluate long-term outcomes. In this study, approximately 1 patient with visual field defect out of two had an improved visual.

Confirmation of functional zones within the human subthalamic nucleus: patterns of connectivity and sub-parcellation using diffusion weighted imaging.

The subthalamic nucleus (STN) is a small, glutamatergic nucleus situated in the diencephalon. A critical component of normal motor function, it has become a key target for deep brain stimulation in the treatment of Parkinson's disease. Animal studies have demonstrated the existence of three functional sub-zones but these have never been shown conclusively in humans. In this work, a data driven method with diffusion weighted imaging demonstrated that three distinct clusters exist within the human STN based on brain connectivity profiles. The STN was successfully sub-parcellated into these regions, demonstrating good correspondence with that described in the animal literature. The local connectivity of each sub-region supported the hypothesis of bilateral limbic, associative and motor regions occupying the anterior, mid and posterior portions of the nucleus respectively. This study is the first to achieve in-vivo, non-invasive anatomical parcellation of the human STN into three anatomical zones within normal diagnostic scan times, which has important future implications for deep brain stimulation surgery.

Scores de mesure fonctionnelle articulaire pour le praticien [Joint functional outcome score for the clinician].

The sports clinician faces multiple treatment options when dealing with overload injuries, and it is important to evaluate their outcomes. Multiple scores exist, some clincian rated (CRO), others patient rated (PRO), the latter being currently favoured. This review presents some of these scores and we selected the ones we feel are the most appropriate for a sports clinician. We considered these common problems: tennis elbow, rotator cuff issues, groin pain, patellofemoral pain syndrome, achilles tendinopathy and ankle instability. In addition, an activity level score is useful to weigh the result in the context of return to performance. These scores help to create a common language between therapists and to evaluate treatments objectively.

Neuronal traits are required for glucose-induced insulin secretion.

The transcriptional repressor RE1 silencer transcription factor (REST) is an important factor that restricts some neuronal traits to neurons. Since these traits are also present in pancreatic beta-cells, we evaluated their role by generating a model of insulin-secreting cells that express REST. The presence of REST led to a decrease in expression of its known target genes, whereas insulin expression and its cellular content were conserved. As a consequence of REST expression, the capacity to secrete insulin in response to mitochondrial fuels, a particularity of mature beta-cells, was impaired. These data provide evidence that REST target genes are required for an appropriate glucose-induced insulin secretion.

Early functional differentiation in the chick embryonic disc: interaction between mechanical activity and extracellular matrix

The mechanical behaviour of ectodermal cells in the area opaca and the supracellular organization of fibronectin in the adjacent extracellular matrix were studied in whole chick blastoderms developing in vitro. The pattern of spontaneous mechanical activity and its modification by immunoglobulins against fibronectin were determined using a real-time image-analysis system. The pattern of fibronectin was studied using immunocytochemical techniques. It was found that the ectodermal cells in the area opaca actively develop a radially oriented contraction, which leads to a distension of the area pellucida from which the embryo develops. Abnormally increased tension resulted in perturbations of gastrulation and neurulation. An optimized mechanical equilibrium within the blastoderm seems to be necessary for normal development. Anti-fibronectin antibodies applied to the basal side of the blastoderm led rapidly and reversibly to an increase of tension in the contracted cells. This observation indicates that modifications of the extracellular matrix can be transmitted to cytoskeletal elements within adjacent cells. The extracellular matrix of the area opaca contains fibronectin arranged in radially oriented fibrils. This orientation corresponds to the direction of migration of the mesodermal cells. Interestingly, the radial pattern of fibronectin is found in the regions where the ectodermal cells are contracted and develop radially oriented forces. This observation suggests that the supracellular assembly of the extracellular materials could be influenced by the mechanical activity of adjacent cells. Possible modulations of the supracellular organization of extracellular matrix by other factors, e.g. diffusible metabolites, is also discussed. The presence of characteristically organized extracellular matrix components, of spatially differentiated cell activities and of reciprocal interactions between them makes the young chick blastoderm an excellent system for physiological studies of the coordinated cellular activities that lead to changes in form, complexity and function.

Analysis of functional and anatomical success following endonasal dacryocystorhinostomy

RésuméLes sténoses des voies lacrymales sont fréquentes surtout chez les patients âgés et provoquent en général un epiphora avec parfois des dacryocystites aiguës ou chroniques. La dacryocystorhinostomie par voie externe (DCREX) a été la technique de choix pour traiter les sténoses post-canaliculaires au XXe siècle. Avec l'avènement de l'endoscopie nasale, l'abord endonasal est devenu facilement accessible et depuis une dizaine d'années, la dacryocystorhinostomie par voie endonasale (DCREN) est en train de supplanter la DCREX dans la majorité des cas.Le but de ce travail est de déterminer les étiologies des sténoses des voies lacrimales, d'évaluer le taux de succès et les complications de la DCREN et de détailler les gestes associés peropératoires.Cette étude rétrospective porte sur 98 patients ayant subi 104 DCREN entre janvier 1994 et février 2006. 78 patients (53 femmes et 25 hommes) présentant 84 sténoses post- canaliculaires remplissent les critères d'inclusion de l'étude. L'âge moyen est de 59 ans (4 - 89 ans).Les résultats obtenus montrent un taux de succès fonctionnel de 94.9% après une première intervention (59/84 DCREN) et de 63.6% pour les DCREN secondaires qui nous ont été référées après d'autres interventions des voies lacrymales (25/84 DCREN). Le suivi postopératoire est de 36,8 mois (12-77 mois). On dénombre 61 gestes rhino-sinusaux associés à la DCREN. Les complications per- et postopératoires sont rares, essentiellement liées aux drains bicanaliculaires. Une étiologie n'a été retrouvée que dans 28% des cas.En conclusion, la DCREN donne d'excellents résultats et peu de complications. En raison des nombreux avantages par rapport à la voie externe et la possibilité du traitement simultané de la pathologie ORL parfois associée, la DCREN est devenue le traitement de premier choix pour les sténoses postcanaliculaires. Le principal défi, quelque soit le type de DCR, est de poser la bonne indication opératoire et en cas d'échec opératoire savoir méticuleusement analyser ses causes