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Sex chromosomes are generally derived from a pair of classical type-A chromosomes, and relatively few alternative models have been proposed up to now. B chromosomes (Bs) are supernumerary and dispensable chromosomes with non-Mendelian inheritance found in many plant and animal species, that have often been considered as selfish genetic elements that behave as genome parasites. The observation that in some species Bs can be either restricted or predominant in one sex raised the interesting hypothesis that Bs could play a role in sex determination. The characterization of putative B master sex-determining (MSD) genes, however, has not yet been provided to support this hypothesis. Here, in Astyanax mexicanus cavefish originating from Pachon cave, we show that Bs are strongly male-predominant. Based on a high-quality genome assembly of a B-carrying male, we characterized the Pachon cavefish B sequence and found that it contains two duplicated loci of the putative MSD gene growth differentiation factor 6b gdf6b). Supporting its role as an MSD gene, we found that the Pachon cavefish gdf6b gene is expressed specifically in differentiating male gonads, and that its knockout induces male-to-female sex reversal in B-carrying males. This demonstrates that gdf6b is necessary for triggering male sex determination in Pachon cavefish. Altogether these results bring multiple and independent lines of evidence supporting the conclusion that the Pachon cavefish B is a “B-sex” chromosome containing duplicated copies of the gdf6b gene acting as an MSD gene promoting male sex determination in this species.

Coordonnateur : Thierry Higuero Auteurs : Laurent Abramowitz L, Helene Pillant-Le Moult; Philippe Hemery, Ghislain Staumont; Thierry Higuero, Francois Pigot, Agnes Senejoux, Jean-Luc Suduca, Cecile Laclotte Duhoux, Alain Castinel, Nadia Fathallah, Beatrice Vinson-Bonnet, Laurent Siproudhis. Groupe de lecture : Laurent Abramowitz, Paul Bendfredj, Dominique Bouchard, Carole Cordonnier, Hubert Dereux, Paul Dieterling, Jean-Luc Faucheron, Philippe Godeberge, Michel Gompel, Thierry Higuero, Pierre Moreau, Francois Mion, Francois Pigot, Elise Pommaret, Agnes Senejoux, Laurent Siproudhis, Denis Soudan, Marc Souffran, Ghislain Staumont, Jean Jacques Tassou, Christian, Thomas, Beatrice Vinson-Bonnet et autres membres anonymes de la SNFCP.

Summary Introduction As little data is available about secondary bleeding after proctological surgery, we conducted a specific survey. Patients and methods Patients operated between November 2008 and April 2009 were prospectively included. Patients were followed until last visit (day 21–28). Severity of bleeding was low (at home stay), moderate (hospitalisation for observation), or severe (transfusion, and/or homeostasis in operating room). Results Included were 1269 patients: haemorrhoidectomy/pexy 527 (41%), fistula treatment 273 (21%), fissurectomy 197 (15%), perianal and pilonidal abscesses 124 (10%), others 148 (12%). Before surgery 78 patients were under long-term treatment with antiplatelet or anticoagulant therapy. Seventy-eight patients (6%) demonstrated 85 bleeding events. Severity rate was: low 22%, moderate 51%, and severe 27%. Ninety-five percent of events occurred before day 15. Univariate study showed increased risk after haemorrhoidopexy ( P −3 ) and anticoagulant treatment ( P = 0.002), decreased risk after fissurectomy and fistulotomy ( P −3 ), and no relation with age, sex or operator. After multivariate study only relationship with anticoagulant treatment remained significant. Conclusion Secondary bleeding occurred in 6% of patients after proctological surgery, requiring a readmission and/or an active treatment in about 75%. Treatment with anticoagulant exposed to increased bleeding frequency.

Resume Le rugby est un sport de contact parfois violent qui expose a un risque medullaire par traumatisme mais aussi par lesions degeneratives precoces. La prevalence de ces pathologies cervicales a augmente avec le professionnalisme. Elles surviennent souvent sur des canaux cervicaux etroits developpementaux, ce qui majore le risque de complication neurologique grave. Une premiere classification des criteres d’aptitude a la pratique du rugby professionnel avait ete adoptee par la Ligue Nationale de Rugby peu apres l’avenement du professionnalisme. Les bilans d’imagerie devenus obligatoires ont permis de depister de tres nombreux canaux cervicaux retrecis chez des joueurs asymptomatiques. L’indice de Torg, utilise initialement, s’avere imparfait. Ces elements ont rendu necessaire l’adaptation de cette classification. Le nouvel outil decisionnel permet une evaluation precise du risque medullaire a l’aide des donnees de l’examen clinique et de l’IRM, voire, si necessaire, des radiographies cervicales. La nouvelle classification est presentee avec ses quatre groupes de risque et d’aptitude (groupe 0 [G0] : aucune pathologie cervicale ; groupe 1 [G1] : pathologie n’entrainant pas de contre-indication a la pratique du rugby en competition ; groupe 2 [G2] : contre-indication relative [sur risque connu, a faire accepter par le joueur] ; groupe 3 [G3] : contre-indication absolue). Elle est discutee. Le risque structurel lie a la pratique du rugby persistant neanmoins, il reste indispensable de responsabiliser le joueur en l’impliquant dans le processus decisionnel.

The 2001/2002 and 2002/2003 breeding seasons of New Zealand sea lions (NZSLs) on the Auckland Islands were marked by a high pup mortality caused by acute bacterial infections. As part of a health survey from 1998/1999 to 2004/2005, tissues and swabs of lesions had been collected at necropsy to identify the bacteria associated with pup mortality. Klebsiella pneumoniae was grown in pure culture from 83% of various organs and lesions in 2001/2002 and 76% in 2002/2003, and less frequently in the following seasons (56% in 2003/2004 and 49% in 2004/2005). Pup isolates of K. pneumoniae showed identical minimal inhibitory concentrations (MIC) of cefuroxime, neomycin, cephalotin, cephalexin and dihydrostreptomycin, suggesting clonal aetiology of the pathogen. Isolates also tested negative for production of extended-spectrum beta-lactamases (ESBLs), which was not in favour of an anthropogenetic origin of the epidemic strain. Pulsed-field gel electrophoresis (PFGE) of XbaI DNA macrorestriction fragments was performed on isolates of K. pneumoniae and Klebsiella oxytoca from 35 pups, thee NZSL adult females, and from three human patients for comparison. PFGE showed that pup isolates of K. pneumoniae were genetically indistinguishable but were neither related to K. pneumoniae from humans and from NZSL adults, nor to K. oxytoca from NZSLs. It is concluded that the 2001/2002 and 2002/2003 epidemics at Sandy Bay rookery were caused by a single K. pneumoniae clonal lineage, genetically different from the strain carried by adult NZSLs. An anthropogenic origin of the K. pneumoniae clone could not be confirmed, but further investigations are required to rule-out such occurrence.

Resume Buts de l'etude. – L'anopexie permet de traiter chirurgicalement la maladie hemorroidaire, avec des suites moins douloureuses que l'hemorroidectomie. Cette information importante a communiquer au patient, peut etre source d'insatisfaction si la douleur vecue depasse la douleur attendue. Evaluer la douleur et l'incapacite physique ressenties apres anopexie par rapport a celles attendues. Evaluer les resultats fonctionnels en fonction des donnees pre- et peroperatoires. Resultats. – Soixante-huit malades consecutifs (56 hommes), d'âge moyen 51 ans (25–83) ont ete inclus prospectivement. Les hemorroides etaient quatre fois de grade 2 (6 %), 52 de grade 3 (76 %) et 12 de grade 4 (18 %). La douleur postoperatoire etait egale ou moindre a celle attendue pour 85 %, avec une meilleure tolerance superieure a 45 ans (p Conclusion. – Une information pragmatique bien qu'imprecise sur la moindre douleur a attendre apres anopexie n'expose pas a la deception des malades. Les resultats fonctionnels ne sont pas influences par la technique operatoire. A l'inverse les troubles de la continence sont peu severes, mais frequents si la ligne d'agrafage est a moins de 6,5 mm de la ligne pectinee.

Resume Objectif : Evaluer, de facon prospective, le risque de recidive locale des cancers du bas rectum stade T2 ou T3 traites par exerese transanale et radiotherapie preoperatoire. Patients et methodes : De 1992 a 1999, 34 patients ont ete traites apres radiotherapie par exerese locale d’un adenocarcinome envahissant (stade T2) ou depassant la musculeuse (stade T3), sans adenopathie perirectale en echographie endorectale ou a l’examen sous anesthesie. Quatre patients traites de facon palliative ou perdus de vue ont ete exclus de l’etude. L’analyse a porte sur les 30 patients restants (huit uT2, huit uT3 et 14 de stade pretherapeutique indetermine). Resultats : Apres un suivi moyen de 74 mois (mediane : 46), le taux de recidive locale a cinq ans etait de 33 %. Le benefice de la radiotherapie n’apparait dans aucun des sous groupes de patients avec ou sans facteur de risque significatif de recidive : taille > 40 mm, marge saine Conclusion : L’exerese locale des cancers du bas rectum de stade T2 ou T3, quelles que soient leurs caracteristiques, expose a un risque important de recidive locale. Ce resultat est constate meme en y associant une radiotherapie preoperatoire. Ce traitement ne peut etre propose qu’a un patient informe et ayant formellement refuse une exerese radicale.

We investigated the effects of two sex steroids (17 β estradiol and testosterone) on five human leukemia cell lines. We observed a statistically significant inhibition of proliferation, dose and time dependent, of the human monoblastic leukemia cell line U937. This inhibition was associated with a dose dependent decrease in the number of CFU-blasts in clonogenic cultures. Cytostatic effect was obtained with doses of 5 μM for estrogen and 10 μM for androgen and was not due to a non-specific cytotoxic effect, some cell viability remained high (>90%) even after 6 days of incubation. More accurately, we demonstrated that growth inhibition was associated with a cell cycle arrest, U937 cells accumulating in G2/M phase. This blockade was dose related with a maximum number of cells accumulating at day 4. Sensitivity of these cells to an S-phase specific agent (hydroxyurea) was not increased, suggesting that these cells were blocked in G2/M and did not undergo mitosis. Expression in U937 cells of high affinity nuclear receptors for estrogen and androgen was negative which was in favour of a type II estrogen binding site, mediated mechanism. Moreover, a small fraction of these cells underwent apoptosis or differentiation with about 12% apoptotic cells and a significant increase (more than 30%) of two myelomonocytic markers (CD13 and CD64). These results demonstrate that the proliferation of some leukemic cells may be inhibited by micromolar concentrations of sex steroids, independently of nuclear receptor expression. The main mechanism seems to be a block in cell cycle associated with modulation of apoptosis and differentiation. It provided additional evidence for the potential value of sex steroids and their analogues in the treatment of leukemias.

A SSFSE sequence is proposed in the sagittal plane for a cine-MRI of the cervical spine in front-line rugby players. Thus one can complete the static study and improve the detection of canal stenosis and the prevention of spinal cord injuries.

But L’infliximab est le traitement de reference des fistules ano-perineales de la maladie de Crohn (MC) [1,2]. Cependant, son effet semble suspensif et les trajets fistuleux persistent en IRM. Le but de cette etude prospective etait d’evaluer, au cours des fistules ano-perineales complexes de MC, l’efficacite a court et a long terme d’un traitement associant infliximab en induction, methotrexate en traitement de fond, et chirurgie proctologique optimale. Patients et Methodes Entre janvier 2006 et novembre 2007, tous les malades avec fistules ano-perineales complexes de MC ont ete inclus prospectivement et consecutivement apres le drainage initial de la suppuration. A l’inclusion, tous recevaient un traitement par methotrexate (25 mg/semaine pendant toute la duree de l’etude) et trois perfusions d’infliximab (5 mg/kg aux semaines 0, 2 et 6). Lors du deuxieme temps chirurgical proctologique, realise a la semaine 4, les setons etaient retires et une procedure optimale etait realisee. L’infliximab etait interrompu apres l’induction et le methotrexate etait poursuivi en entretien. La reponse clinique initiale etait definie par une diminution d’au moins 50 % du nombre des ecoulements fistuleux lors d’au moins deux visites consecutives. L’objectif principal de l’etude etait la reponse clinique a la semaine 14. Les objectifs secondaires etudies etaient : 1) le delai median de perte de reponse chez les repondeurs a la semaine 14 ; 2) l’evolution du Perineal Disease Activity Index (PDAI) et du score IRM de Van Assche ; 3) la tolerance du traitement. Resultats Trente-quatre malades (26 femmes, âge median : 38,5 ans) atteints de fistules ano-perineales fistules complexes ont ete inclus : 29 % avaient une stenose ano-rectale et 26 % une fistule recto-vaginale ; 62 % etaient cortico-dependants ou cortico-resistants, 62 % avaient deja recu de l’azathioprine et 26 % de l’infliximab. Le deuxieme temps chirurgical proctologique a consiste en une ablation simple de seton (n = 7), une fistulotomie (4), une application de colle biologique (10), un lambeau (11), une intervention de Musset (2). A la semaine 14, 85 % des malades etaient repondeurs dont 73,5 % de reponse complete. Le delai median de perte de reponse etait de 69 semaines. Aux semaines 0, 14 et 50, le PDAI median etait respectivement de 11, 3 puis 0 (p Conclusion Un traitement associant infliximab en induction et chirurgie proctologique optimisee permet d’obtenir une reponse clinique rapide en cas de fistules ano-perineales complexes de MC. Le traitement d’entretien par le methotrexate en monotherapie permet ensuite de maintenir cette reponse clinique et anatomique (IRM) pendant plus d’un an. Le methotrexate pourrait etre compare a l’infliximab en traitement d’entretien de la MC ano-perineale fistulisante.

Infrared spectra of NH 2 CHRCOO − Na + and [NH 2 CHRCOO] − Ag + (where R = H, CH 3 ,C 6 H 5 CH 2 H 2 and p OHC 6 H 4 CH 2 ) were studied using N-deuterated analogs. Assignments of frequencies are proposed for the different structural groups, with emphasis on the wagging amino vibration γ(NH 2 ) and a comparison with other works on amino acid chelatea is made.