982 resultados para spermatozoa, microtubular defect


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Agates from the Bighorn district in Montana (USA), the so-called Dryhead area, and their adjacent host rocks have been examined in the present study. Analyses by XRD, polarizing microscopy, LA-ICP-MS, cathodoluminescence (CL), SEM and of oxygen isotopes were performed to obtain information surrounding the genesis of this agate type. Investigations of the agate microstructure by polarizing microscopy and CL showed that chalcedony layers and macrocrystalline quartz crystals may have formed by crystallization from the same silica source by a process of self-organization. High defect densities and internal structures (e. g. sector zoning) of quartz indicate that crystallization went rapidly under non-equilibrium conditions. Most trace-element contents in macrocrystalline quartz are less than in chalcedony due to a process of `self-purification', which also caused the formation of Fe oxide inclusions and spherules. Although the agates formed in sedimentary host rocks, analytical data indicate participation of hydrothermal fluids during agate formation. Trace elements (REE distribution patterns, U contents up to 70 ppm) and CL features of agate (transient blue CL), as well as associated minerals (fluorite, REE carbonates) point to the influence of hydrothermal processes on the genesis of the Dryhead agates. However, formation temperatures <120 degrees C were calculated from O-isotope compositions between 28.9 parts per thousand (quartz) and 32.2 parts per thousand (chalcedony).

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Vaginal delivery can cause lesions of the various pelvic structures responsible for the mechanisms of continence. These lesions may perhaps be prevented in the future by measuring pressure generated during childbirth. Tear of the anal sphincter during childbirth is a marker of a global impairment of the urinary, ano-rectal and sexual pelvic functions in the short and medium term. Persistence of a defect of the anal sphincter is frequent in spite of immediate suture. The correlation between these defects and ano-rectal incontinence are not established in our experience. The quality of the contraction of the sphincter complex and pubo-rectal sling seems to play a more important role in ano-rectal continence after a traumatic childbirth.

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Atresia of the coronary sinus (ACS) is a rare congenital anomaly. When associated with persistent left superior vena cava (PLSVC), this defect could have no significant hemodynamic effect, and the patient might remain asymptomatic. However, vascular interventions might induce changes or complications that could show the anomaly. Appropriate management requires a good understanding of this condition. We present the first reported case of ACS and PLSVC occurring after thrombosis of the innominate vein (IV) after central venous catheter placement. The patient presented with atypical subacute chest pain and recurrent extrasystoles. Diagnosis and characterization of vascular anomalies was made by computed tomography phlebography, and the patient was successfully managed by endovascular recanalization of the IV.

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Peptide signaling presumably occupies a central role in plant development, yet only few concrete examples of receptor-ligand pairs that act in the context of specific differentiation processes have been described. Here we report that second-site null mutations in the Arabidopsis leucine-rich repeat receptor-like kinase gene barely any meristem 3 (BAM3) perfectly suppress the postembryonic root meristem growth defect and the associated perturbed protophloem development of the brevis radix (brx) mutant. The roots of bam3 mutants specifically resist growth inhibition by the CLAVATA3/ENDOSPERM SURROUNDING REGION 45 (CLE45) peptide ligand. WT plants transformed with a construct for ectopic overexpression of CLE45 could not be recovered, with the exception of a single severely dwarfed and sterile plant that eventually died. By contrast, we obtained numerous transgenic bam3 mutants transformed with the same construct. These transgenic plants displayed a WT phenotype, however, supporting the notion that CLE45 is the likely BAM3 ligand. The results correlate with the observation that external CLE45 application represses protophloem differentiation in WT, but not in bam3 mutants. BAM3, BRX, and CLE45 are expressed in a similar spatiotemporal trend along the developing protophloem, up to the end of the transition zone. Induction of BAM3 expression upon CLE45 application, ectopic overexpression of BAM3 in brx root meristems, and laser ablation experiments suggest that intertwined regulatory activity of BRX, BAM3, and CLE45 could be involved in the proper transition of protophloem cells from proliferation to differentiation, thereby impinging on postembryonic growth capacity of the root meristem.

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The issue of specificity of delusions in schizophrenia is still a matter of debate. The authors analyze the delusion formation in schizophrenia from a prototypical, phenomenological point of view, focusing on the subject's experience. This perspective links delusion formation to the autistic predisposition, which is considered here as the elementary phenotypic expression of the vulnerability to schizophrenia. Autism is viewed as a defective preconceptual (i.e., before language) attunement to the world. It impedes the individual's sharing of "common sense" with others and impairs the ability to project into the future. The development of delusions is illustrated, in part, by Klaus Conrad's work on the onset of paranoid schizophrenia. Delusions are viewed as transformations of the structure of experiencing. When threatened in future ability to be, the autistic, vulnerable person looks for the clues to becoming by attributing significance to disparate elements of the environment, which become self-referential. The link established between these disparate elements is based on universal characteristics that give the schizophrenic delusion a metaphysical quality. The transitivistic experience in delusions of control and omnipotence points to a specific way of crossing the border between "mine" and "yours" (disturbances of the experiencing "I"). What strikes a clinician in these delusions is that the normally tacit link between the sense of being and the sense of acting becomes quite apparent. The authors also propose a specificity in the themes of schizophrenic delusions. Delusions acquire a schizophrenic quality when ontological (i.e., universal) elements of the discourse between the locutor and the Other dominate at the expense of the worldly elements. It is emphasized that delusional content and form are dialectically related and hardly distinguishable. The authors consider the delusion formation as a phenomenon of emergence, a situation in which a new qualitative order arises from the reorganization of essentially unchanged elements. To consider schizophrenia as an emergent, particular way of experiencing, related to the autistic defect, has important consequences for research and for treatment. A dialectic exchange is needed between prototypical models generated by phenomenological inquiry and empirical, operational validation of testable aspects of such models.

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INTRODUCTION: Mutations in the TMEM70 are the most common cause of nuclear ATP synthase deficiency resulting in a distinctive phenotype characterized by severe neonatal hypotonia, hypertrophic cardiomyopathy (HCMP), facial dysmorphism, severe lactic acidosis, hyperammonemia and 3-methylglutaconic aciduria (3-MGA). METHODS AND RESULTS: We collected 9 patients with genetically confirmed TMEM70 defect from 8 different families. Six were homozygous for the c.317-2A>G mutation, 2 were compound heterozygous for mutations c.317-2A>G and c.628A>C and 1 was homozygous for the novel c.701A>C mutation. Generalized hypotonia, lactic acidosis, hyperammonemia and 3-MGA were present in all since birth. Five patients presented acute respiratory distress at birth requiring intubation and ventilatory support. HCMP was detected in 5 newborns and appeared a few months later in 3 additional children. Five patients showed a severe and persistent neonatal pulmonary hypertension (PPHN) requiring Nitric Oxide (NO) and/or sildenafil administration combined in 2 cases with high-frequency oscillatory (HFO) ventilation. In 3 of these patients, echocardiography detected signs of HCMP at birth. CONCLUSIONS: PPHN is a life-threatening poorly understood condition with bad prognosis if untreated. Pulmonary hypertension has rarely been reported in mitochondrial disorders and, so far, it has been described in association with TMEM70 deficiency only in one patient. This report further expands the clinical and genetic spectrum of the syndrome indicating PPHN as a frequent and life-threatening complication regardless of the type of mutation. Moreover, in these children PPHN appears even in the absence of an overt cardiomyopathy, thus representing an early sign and a clue for diagnosis.

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Objective: The aim of this study was to investigate the feasibility of transventricular-transseptal approach (TVSA) for extrapleural transcatheter aortic valved stent implantation via a subxyphoidian access. Methods: In five porcine experiments (52.3 +/- 10.9 kg) the right ventricle was exposed via subxyphoidian access. Under the guidance of intracardiac echocardiography (ICE) and fluoroscopy, the transseptal access from right ventricle to left ventricle was created progressively by puncture and dilation with dilators (8F-26F). Valved stents built in-house from commercial tanned pericardium and self-expandable Nitinol stents were loaded into a cartridge. A delivery sheath was then introduced from the right ventricle into the left ventricle and then into the ascending aorta. The cartridge was connected and the valved stent was deployed in the aortic position. Then, the ventricular septal access was sealed with an Amplatzer septal occluder device and the right ventricular access was closed by tying prepared purse-string suture directly. Thirty minutes after the whole procedure, the animals were sacrificed for macroscopic evaluation of the position of valved stent and septal closure device. Result: Procedural success of TVSA was 100% at the first attempt. Mean procedure time was 49 +/- 4 min. Progressive dilatation of the transseptal access resulted in a measurable ventricular septal defect (VSD) after dilator sizes 18F and more. All valved stents were delivered at the target site over the native aortic valve with good acute valve function and no paravalvular leaks. During the procedure, premature beats (5/5) and supraventriclar tachycardias (5/5) were observed, but no atrial-ventricular block (0/5) occurred. Heart rate before (after) was 90 +/- 3 beats min(-1) (100 +/- 2 beats min(-1): p < 0.05), whereas blood pressure was 60 + 1 mm Hg (55 + 2 mm Hg (p < 0.05)). Total blood loss was 280 + 10 ml. The Amplatzer septal occluder devices were fully deployed and the ventricular septal accesses were sealed successfully, without detectable residual shunt. Conclusion: Trans-catheter implantation of aortic valved stent via extrapleural transventricular-transseptal access is technically feasible and has the potential for a simplified procedure under local anaesthesia. (C) 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B. V. All rights reserved.

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Fraser syndrome is a rare autosomal recessive disorder characterized by cryptophthalmos, cutaneous syndactyly, laryngeal, and urogenital malformations. We present a population-based epidemiological study using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network of birth defect registries. Between January 1990 and December 2008, we identified 26 cases of Fraser syndrome in the monitored population of 12,886,464 births (minimal estimated prevalence of 0.20 per 100,000 or 1:495,633 births). Most cases (18/26; 69%) were registered in the western part of Europe, where the mean prevalence is 1 in 230,695 births, compared to the prevalence 1 in 1,091,175 for the rest of Europe (P = 0.0003). Consanguinity was present in 7/26 (27%) families. Ten (38%) cases were liveborn, 14 (54%) pregnancies were terminated following prenatal detection of a serious anomaly, and 2 (8%) were stillborn. Eye anomalies were found in 20/24 (83%), syndactyly in 14/24 (58%), and laryngeal anomalies in 5/24 (21%) patients. Ambiguous genitalia were observed in 3/24 (13%) cases. Bilateral renal agenesis was present in 12/24 (50%) and unilateral in 4/24 (17%) cases. The frequency of anorectal anomalies was particularly high (42%). Most cases of Fraser syndrome (85%) are suspected prenatally, often due to the presence of the association of renal agenesis and cryptophthalmos. In the European population, a high proportion (82%) of pregnancies is terminated, thus reducing the live birth prevalence to a third of the total prevalence rate.

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Many studies demonstrate that intestinal inflammation is either initiated or exaggerated by a component of the normal microbiota, most likely commensal bacteria or products derived from these organisms. We review the nature of human inflammatory bowel disease, the evidence for the involvement of the normal bacterial flora in these disorders and the relevance of maintaining the integrity of the epithelial barrier. Moreover, we, and others, have shown abnormal mitochondria structure in tissue resections from patients with inflammatory bowel disease and tissues from rodents that demonstrated psychological stress-induced increases in epithelial permeability. Thus, we also consider the possibility that a defect in epithelial mitochondrial function would predispose an individual to respond to their commensal bacteria flora - no longer considering them as a beneficial passive inhabitant, but rather perceiving them as a threatening and pro-inflammatory stimulus. In support of this postulate, we discuss our recent findings from an in vitro model showing that the human colon-derived T84 cell line exposed to the metabolic stressor, dinitrophenol, and the non-pathogenic, non-invasive, Escherichia coli (strain HB101) display a loss of barrier function, increased signal transduction and increased production of the chemokine, interleukin 8.

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BACKGROUND: There have been anecdotal reports of anterior ischemic optic neuropathy (AION) occurring in eyes with optic disc drusen (ODD), but the clinical features of this condition have not been well characterized. OBJECTIVES: To better describe the clinical features of AION associated with ODD and to compare the clinical features of this condition with those of "garden variety" nonarteritic AION. METHODS: We reviewed the medical records of 20 patients who experienced an episode of AION in an eye with ODD. In 4 patients, both eyes were affected; thus, 24 eyes were studied. The diagnosis of ODD was made by ophthalmoscopic identification, orbital ultrasonography, or computed tomographic scanning. We recorded age, sex, vascular risk factors, symptoms, visual acuity, visual fields, and results of the follow-up examination in all patients. These findings were compared with data from previously reported series of patients with nonarteritic AION. RESULTS: Our 20 patients included 14 men and 6 women (age range, 18-69 years; mean, 49.4 years). Vascular risk factors were identified in 10 patients (50%). Three patients reported episodes of transient visual loss before their fixed deficit. The visual acuity at the initial examination was 20/60 or better in 15 (62%) of the 24 eyes; 8 had a visual acuity of 20/20. The predominant pattern of visual field loss was an altitudinal or arcuate defect in 19 (79%) and a centrocecal scotoma in 5 (21%) of the 24 eyes. There was subjective worsening of vision before the initial neuro-ophthalmic examination in 11 eyes (46%) and objective documentation of progression in 7 eyes (29%). The final visual acuity was 20/40 or better in 13 (62%) of 21 eyes and 20/200 or worse in 3 (14%) of 21 eyes. CONCLUSIONS: Our patients were strikingly similar to those with nonarteritic AION unassociated with drusen in regard to prevalence of vascular risk factors, pattern of visual field loss, and occurrence of a subsequent similar event in the fellow eye. In contrast, however, patients with ODD-AION were younger than those with nonarteritic AION, were more likely to report preceding episodes of transient visual obscuration, and enjoyed a more favorable visual outcome.

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Abstract : Host-Cell Factor 1 (HCF-1) was first discovered in the study of the herpes simplex virus (HSV) infection. HCF-1 is one of the two cellular proteins that compose the VP16-induced complex, a key activator of HSV lytic infection. lncleed, when HSV infects human cells, it is able to enter two modes of infection: lytic or latent. The V`P16-induced complex promotes the lytic mode and in so doing the virus targets important cellular regulatory proteins, such as HCF-1, to manipulate the status of the infected cell. Indeed, HCF-1 regulates human cell proliferation and the cell cycle at different steps. In human, HCF-1 is unusual in that it undergoes a process of proteolytic maturation that results from cleavages at six centrally located 26 amino acid repeats called HCF-1pro repeats. This generates a heterodimeric complex of stably associated amino- (HCF-1n) and carboxy- (HCF-1c) terminal subunits. The absence of the HCF-1 N or HCF-1; subunit leads predominantly to either G1 or M phase defects, respectively. We have hypothesized that HCF-1 forms a heterodimeric complex to permit communication between the two subunits of HCF-1 involved in regulating different phases of the cell cycle. Indeed, there is evidence for such inter-subunit communication because a point mutation called P134S in the HCF-1N subunit in the temperature-sensitive hamster cell line tsBN67 causes, addition to G1- phase defects associated with the HCF-1n subunit, M-phase defects similar to the defects seen upon loss of HCF-1 function. Furthermore, inhibition of the proteolytic maturation of HCF-1 by deletion of the six HCF-1pro repeats (HCF-1Aimo) also leads to M-phase defects, specifically cytokinesis defects leading to binucleation, indicating that there is loss of HCF-15 function in the absence of HCF-1 maturation. I demonstrate that individual point mutations in each of the six HCF-1pro repeats that prevent HCF-1 proteolytic maturation also lead to binucleation; however, this defect can be latgely rescued by the presence of just one HCF-1pRO sequence in I-ICF»1. These results argue that processing itself is important for the HCF-1g function. In fact, until now, the hypothesis was that the proteolytic processing per se is more important for HCF-1C function than the proteolytic processing region. But I show that processing per se is not sufticient to rescue multinucleation, but that the HCF-lpm sequence itself is crucial. This discovery leads to the conclusion that the I-ICF-1pRO repeats have an additional function important for HCF-le function. From the studies of others, one potential function of the HCF-lrxo tepeats is as a binding site for O-link NAcetyl glycosamine tansferase (OGT) to glycosylate an HCF-1n-sunbunit region called the Basic region. This new function suggests the Basic region of HCF-1n is also implicated in the communication between the two subunits. This inter-subunit communication was analyzed in more detail with the studies of the Pl34S mutation and the residues 382-450 region of HCF-l that when removed prevents HCF-l subunit association. I demonstrate that the point mutation also leads to a binucleation defect in Hela cells as well as in the tsBN67 cells. In addition, the effect of this mutation on the regulation of HCF-1c activity seems to interfere with that of the HCF-lpgg repeats because the sum of the deletion of the proteolytic processing region and the point mutation surprisingly leads to re-establishment of correct cytokinesis. The study of the 382-450 HCF-lN region also yielded surprising results. This region important for the association of the two subunits is also important for both HCF-1c function in M phase and G1 phase progression. Thus, I have discovered two main functions of this region: its role in the regulation of HCF-lc function in M phase and its involvement in the regulation of G1/S phase ?- an HCF-1n function. These results support the importance of inter-subunit communication in HCF-1 functions. My research illuminates the understanding of the interaction of the two subunits by showing that the whole HCF-1n subunit is involved in the inter-subunit communication in order to regulate HCF-1c function. For this work, I was concentrated on the study of cytokinesis; the first phenotype showing the role of HCF-1c in the M phase. Then, I extended the study of the M phase with analysis of steps earlier to cytokinesis. Because some defects in the chromosome segregation was already described in the absence of HCF-1, I decided to continue the study of M phase by checking effects on the chromosome segregation. I showed that the HCF-1n subunit and HCF-1pro repeats are both important for this key step of M phase. I show that the binucleation phenotype resulting from deletion or mutation in HCF-1pro repeats, Pl34S point mutation or the lack of the region 382-450 are correlated with micronuclei, and chromosome segregation and alignment defects. This suggests that HCF«lç already regulates M phase during an early step and could be involved in the complex regulation of chromosome segregation. Because one of the major roles of HCF-1 is to be a transcription regulator, I also checked the capacity of HCF-1 to bind to the chromatin in my different cell lines. All my recombinant proteins can bind the chromatin, except for, as previously described, the HCF-1 with the P134S point mutation, This suggests that the binding of HCF-1 to the chromatin is not dependant to the Basic and proteolytic regions but more to the Kelch domain. Thus, if the function of HCF-ig in M phase is dependant to its chromatin association, the intercommunication and the proteolytic region are not involved in the ability to bind to the chromatin but more to bind to the right place of the chromatin or to be associated with the co-factors. Résumé : L'étude de l'infection par le virus Herpes Simplex (HSV) a permis la découverte de la protéine HCF-1 (Host-Cell Factor). HCF-1 est une des protéines cellulaires qui font partie du complexe induit par VP16 ; ce complexe est la clef pour l'activation de la phase lytique de HSV. Afin de manipuler les cellules infectées, le complexe induit pas le VPIG devrait donc cibler les protéines importantes pour la régulation cellulaire, telles que la protéine HCF-1. Cette dernière s'avère donc être un senseur pour la cellule et devrait également jouer un rôle de régulation lors des différentes phases du cycle cellulaire. Chez l'humain, HCF-1 a la particularité de devoir passer par une phase de maturation pour devenir active. Lors de cette maturation, la protéine subit une coupure protéolytique au niveau de six répétitions composées de 26 acides aminés, appelé HCF-1pro repeats. Cette coupure engendre la formation d'un complexe formé de deux sous-unités, HCF-1n et HCF-1c, associées l'une à l'autre de façon stable. Enlever la sous-unité HCF-IN ou C entraîne respectivement des défauts dans la phase G1 et M. Nous pensons donc que HCF-1 forme un complexe hétérodimérique afin de permettre la communication entre les molécules impliquées dans la régulation des différentes phases du cycle cellulaire. Cette hypothèse est déduite suite à deux études: l'une réalisée sur la lignée cellulaire tsBN67 et l'autre portant sur l'inhibition de la maturation protéolytique. La lignée cellulaire tsBN67, sensible à la température, porte la mutation Pl 345 dans la sous-unité HCF-1n. Cette mutation, en plus d'occasionner des défauts dans la phase G1 (défauts liés à la sous-unité HCF-1N), a aussi pour conséquence d'entrainer des défauts dans la phase M, défauts similaires à ceux dus a la perte de la sous-unité HCF-1c. Quant à la maturation protéolytique, l'absence de la région de la protéolyse provoque la binucléation, défaut lié à la cytokinèse, indiquant la perte de la fonction de la sous-unité HCF-1c. Au cours de ma thèse, j'ai démontré que des mutations dans les HCF-1=no repeats, qui bloquent la protéolyse, engendrent la binucléation ; cependant ce défaut peut être corrigé pas l'ajout d'un HCF-1pro repeat dans un HCF-1 ne contenant pas la région protéolytique. Ces résultats soutiennent l'idée que la région protéolytique est importante pour le bon fonctionnement de HCF-1c. En réalité jusqu'a maintenant on supposait que le mécanisme de coupure était plus important que la région impliquée pour la régulation de la fonction de HCF-1;. Mais mon étude montre que la protéolyse n'est pas suffisante pour éviter la binucléation ; en effet, les HCF-1pro repeats semblent jouer le rôle essentiel dans le cycle cellulaire. Cette découverte conduit à la conclusion que les HCF-1pro repeats ont sûrement une fonction autre qui serait cruciale pour la foncton de HCF-1c. Une des fonctions possibles est d'être le site de liaison de l'O-linked N-acetylglucosamine transférase (OGT) qui glycosylerait la région Basique de HCF-1n. Cette nouvelle fonction suggère que la région Basique est aussi impliquée dans la communication entre les deux sous- unités. L'intercommunication entre les deux sous-unités ai été d'ailleurs analysée plus en détail dans mon travail à travers l'étude de la mutation Pl34S et de la région 382-450, essentielle pour l'association des deux sous»unités. J'ai ainsi démontré que la mutation P134S entraînait aussi des défauts dans la cytokinése dans la lignée cellulaire Hela, de plus, son influence sur HCF-1c semble interférer avec celle de la région protéolytique. En effet, la superposition de ces deux modifications dans HCF-1 conduit au rétablissement d'une cytokinése correcte. Concernant la région 382 à 450, les résultats ont été assez surprenants, la perte de cette région provoque l'arrêt du cycle en G1 et la binucléation, ce qui tend à prouver son importance pour le bon fonctionnement de HCF-1n et de HCF-1c. Cette découverte appuie par conséquent l'hypotl1èse d'une intercommunicatzion entre les deux sous-unités mettant en jeu les différentes régions de HCF-1n. Grâce à mes recherches, j'ai pu améliorer la compréhension de l'interaction des deux sous-unités de HCF-1 en montrant que toutes les régions de HCF-1n sont engagées dans un processus d'intercommunication, dont le but est de réguler l'action de HCF-1c. J'ai également mis en évidence une nouvelle étape de la maturation de HCF-1 qui représente une phase importante pour l'activation de la fonction de HCF-1c. Afin de mettre à jour cette découverte, je me suis concentrée sur l'étude de l'impact de ces régions au niveau de la cytokinése qui fut le premier phénotype démontrant le rôle de HCF-1c dans la phase M. A ce jour, nous savons que HCF-1c joue un rôle dans la cytokinèse, nous ne connaissons pas encore sa fonction précise. Dans le but de cerner plus précisément cette fonction, j'ai investigué des étapes ultérieures ai la cytokinèse. Des défauts dans la ségrégation des chromosomes avaient déjà été observés, ai donc continué l'étude en prouvant que HCF-1n et les HCF-1pro repeats sont aussi importants pour le bon fonctionnement de cette étape clef également régulée par HCF-1c. J' ai aussi montré que la région 382-450 et la mutation P134S sont associées à un taux élevé de micronoyaux, de défauts dans la ségrégation des chromosomes. L'une des fonctions principales de HCF-1 étant la régulation de la transcription, j'ai aussi contrôlé la capacité de HCF-1 à se lier à la chromatine après insertion de mutations ou délétions dans HCF-1n et dans la région protéolytique. Or, à l'exception des HCF-1 contenant la mutation P134S, la sous-unité HCF-1c des HCF-1 tronquées se lie correctement à la chromatine. Cette constatation suggère que la liaison entre HCF-1c et chromatine n'est pas dépendante de la région Basique ou Protéolytique mais peut-être vraisemblablement de la région Kelch. Donc si le rôle de HCF-1c est dépendant de sa capacité â activer la transcription, l'intercommunication entre les deux sous-unités et la région protéolytique joueraient un rôle important non pas dans son habileté à se lier à la chromatine, mais dans la capacité de HCF-1 à s'associer aux co-facteurs ou à se placer sur les bonnes régions du génome.

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Signal transducer and activator of transcription (STAT) 3 is a pleiotropic transcription factor with important functions in cytokine signaling in a variety of tissues. However, the role of STAT3 in the intestinal epithelium is not well understood. We demonstrate that development of colonic inflammation is associated with the induction of STAT3 activity in intestinal epithelial cells (IECs). Studies in genetically engineered mice showed that epithelial STAT3 activation in dextran sodium sulfate colitis is dependent on interleukin (IL)-22 rather than IL-6. IL-22 was secreted by colonic CD11c(+) cells in response to Toll-like receptor stimulation. Conditional knockout mice with an IEC-specific deletion of STAT3 activity were highly susceptible to experimental colitis, indicating that epithelial STAT3 regulates gut homeostasis. STAT3(IEC-KO) mice, upon induction of colitis, showed a striking defect of epithelial restitution. Gene chip analysis indicated that STAT3 regulates the cellular stress response, apoptosis, and pathways associated with wound healing in IECs. Consistently, both IL-22 and epithelial STAT3 were found to be important in wound-healing experiments in vivo. In summary, our data suggest that intestinal epithelial STAT3 activation regulates immune homeostasis in the gut by promoting IL-22-dependent mucosal wound healing.

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Islet-brain 1 (IB1), a regulator of the pancreatic beta-cell function in the rat, is homologous to JIP-1, a murine inhibitor of c-Jun amino-terminal kinase (JNK). Whether IB1 and JIP-1 are present in humans was not known. We report the sequence of the 2133-bp human IB1 cDNA, the expression, structure, and fine-mapping of the human IB1 gene, and the characterization of an IB1 pseudogene. Human IB1 is 94% identical to rat IB1. The tissue-specific expression of IB1 in human is similar to that observed in rodent. The IB1 gene contains 12 exons and maps to chromosome 11 (11p11.2-p12), a region that is deleted in DEFECT-11 syndrome. Apart from an IB1 pseudogene on chromosome 17 (17q21), no additional IB1-related gene was found in the human genome. Our data indicate that the sequence and expression pattern of IB1 are highly conserved between rodent and human and provide the necessary tools to investigate whether IB1 is involved in human diseases.

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BACKGROUND: Prospective assessment of pedicled extrathoracic muscle flaps for the closure of large intrathoracic airway defects after noncircumferential resection in situations where an end-to-end reconstruction seemed risky (defects of > 4-cm length, desmoplastic reactions after previous infection or radiochemotherapy). METHODS: From 1996 to 2001, 13 intrathoracic muscle transpositions (6 latissimus dorsi and 7 serratus anterior muscle flaps) were performed to close defects of the intrathoracic airways after noncircumferential resection for tumor (n = 5), large tracheoesophageal fistula (n = 2), delayed tracheal injury (n = 1) and bronchopleural fistula (n = 5). In 2 patients, the extent of the tracheal defect required reinforcement of the reconstruction by use of a rib segment embedded into the muscle flap followed by temporary tracheal stenting. Patient follow-up was by clinical examination bronchoscopy and biopsy, pulmonary function tests, and dynamic virtual bronchoscopy by computed tomographic (CT) scan during inspiration and expiration. RESULTS: The airway defects ranged from 2 x 1 cm to 8 x 4 cm and involved up to 50% of the airway circumference. They were all successfully closed using muscle flaps with no mortality and all patients were extubated within 24 hours. Bronchoscopy revealed epithelialization of the reconstructions without dehiscence, stenosis, or recurrence of fistulas. The flow-volume loop was preserved in all patients and dynamic virtual bronchoscopy revealed no significant difference in the endoluminal cross surface areas of the airway between inspiration and expiration above (45 +/- 21 mm(2)), at the site (76 +/- 23 mm(2)) and below the reconstruction (65 +/- 40 mm(2)). CONCLUSIONS: Intrathoracic airway defects of up to 50% of the circumference may be repaired using extrathoracic muscle flaps when an end-to-end reconstruction is not feasible.

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Background and aim: Wilson disease (WD) is an inherited disorder ofhepatic copper excretion leading to toxic accumulation of copper in theliver as well as the brain, cornea, and other organs. The defect is due tomutations of the copper-transporting ATPase ATP7B. Here, we describethe adult cases of hepatic WD diagnosed at the CHUV between 2005and 2010.Methods: Clinical manifestions, results of diagnostic tests, and follow-upof adult patients with hepatic WD were recorded systematically.Results: Seven new adult cases of hepatic WD were diagnosed in ourcenter between 2005 and 2010. Three were women and 4 men, with amedian a ge at d iagnosis o f 24 (range, 1 8-56) years. Three patientspresented with acute liver failure (ALF), three with persistently elevatedliver function tests, and one with a dvanced cirrhosis. None hadneurological manifestations. Only one patient, presenting with ALF, had aKayser-Fleischer corneal ring. Median ceruloplasmin levels at diagnosiswere 0.13 (range, <0.03-0.30) g/l, median 24 h urinary copper excretion6.3 (range, 0.4-62.0) μmol/24 h, and median hepatic copperconcentration 591 (range, 284-1049) μg/g. At least one mutation in theATP7B g ene was i dentified in a ll patients. Allelic frequency of t hecommon H1069Q mutation was 14%. Two patients presenting with ALFand the one with advanced cirrhosis underwent successful l ivertransplantation. One patient with ALF recovered under chelator therapy.D-penicillamine was used as first-line chelator treatment, with a switch totrientine due to adverse effects in 2 out of 4 patients u nder l ong-termtreatment.Conclusions: The clinical presentation of WD and the performance ofdiagnostic tests are variable. A high index of suspicion i n clinicallycompatible situations i s key, with a combination of tests allowing thediagnosis of WD.