Vie privée des ecclésiastiques prélats, et autres fonctionnaires publics qui n'ont point prêté leur serment sur la Constitution civile du clergé. [Partie 1-2] / [par M. J.-A. Dulaure]

Collection : Les archives de la Révolution française ; 8.1465

Fanconi anemia and genome stability : the role of FANCM

RÉSUMÉ: Le génome de toute cellule est susceptible d'être attaqué par des agents endogènes et exogènes. Afin de préserver l'intégrité génomique, les cellules ont développé des multitudes de mécanismes. La réplication de l'ADN, une étape importante durant le cycle cellulaire, constitue un stress et présente un danger important pour l'intégrité du génome. L'anémie de Fanconi est une maladie héréditaire rare dont les protéines impliquées semblent jouer un rôle crucial dans la réponse au stress réplicatif. La maladie est associée à une instabilité chromosomique ainsi qu'à une forte probabilité de développer des cancers. Les cellules des patients souffrant de l'anémie de Fanconi sont sensibles à des agents interférant avec la réplication de l'ADN, et plus particulièrement àdes agents qui fient les deux brins d'ADN d'une manière covalente. L'anémie de Fanconi est une maladie génétiquement hétérogène. Treize protéines ont pu être identifiées. Elles semblent figurer dans une même voie de signalisation qui est aussi connue sous le nom de « FA/BRCA pathway », car un des gènes est identique au gène BRCA2 (breast cancer susceptibility gene 2). Huit protéines forment un complexe nucléaire dont l'intégrité est nécessaire à la monoubiquitination de deux autres protéines, FANCD2 et FANCI, en réponse à un stress réplicatif. A ce jour, la fonction moléculaire des protéines du « FA/BRCA pathway »reste encore mal décrite. Au début de mon travail de thèse, nous avons donc décidé de purifier les protéines du complexe nucléaire et d'étudier leurs propriétés biochimiques. Nous avons tout d'abord étudié les cinq protéines connues à l'époque qui sont FANCA, FANCC, FANCE, FANCF et FANCG. Par la suite, nous avons étendu notre étude à des protéines découvertes plus récemment, FANCL, FANCM et FAAP24, en concentrant finalement notre travail sur la caractérisation de FANCM. FANCM, contrairement aux autres protéines du complexe, est constituée de deux domaines conservés suggérant un rôle important dans le métabolisme de l'ADN. Il s'agit d'un domaine « DEAH box hélicase »situé dans la partie N-terminale et d'un domaine « ERCC4 nuclease »situé dans la partie C-terminale de la protéine. Dans cette étude, nous avons purifié avec succès la protéine FANCM entière à partir d'un système hétérologue. Nous montrons que FANCM s'attache de manière spécifique à des jonctions de Holliday et des fourches de réplication. De plus, nous démontrons que FANCM peut déplacer le point de jonction de ces structures via son domaine hélicase de manière dépendante de l'ATP. FANCM est aussi capable de dissocier de grands intermédiaires de la recombinaison, via la migration de jonctions de Holliday à travers une région d'homologie de 2.6 kb. Tous ces résultats suggèrent que FANCM peut s'attacher spécifiquement à des fourches de réplication et à des jonctions de Holliday in vitro et que son domaine hélicase est associé à une activité migratoire efficace. Nous pensons que FANCM peut avoir un rôle direct sur les intermédiaires de réplication. Ceci est en accord avec l'idée que les protéines de l'anémie de Fanconi coordonnent la réparation de l'ADN au niveau des fourches de réplication arrêtées. Nos résultats donnent une première indication quant au rôle de FANCM dans la cellule et peuvent contribuer à élucider la fonction de cette voie de signalisation peu comprise jusqu'à présent. SUMMARY: The genome of every cell is subject to a constant offence by endogenous and exogenous agents. Not surprisingly; cells have evolved a multitude of mechanisms which aim at preserving genomic integrity. A key step during the life cycle of a cell, DNA replication itself, constitutes a special danger to the integrity of the genome. The proteins defective in the rare hereditary disease Fanconi anemia (FA) are suspected to play a crucial role in the cellular response to DNA replication stress. The disease is associated with chromosomal instability and pronounced cancer susceptibility. Cells from Fanconi anemia patients are sensitive to a variety of agents which interfere with DNA replication, DNA interstrand cross-linking agents being particularly threatening to their survival. Fanconi anemia is a genetically heterogeneous disease with 13 different proteins identified, which seem to work together in a common pathway. Since one of the FA genes is identical to the breast cancer susceptibility gene BRCA2, it is also referred to as the FA/BRCA pathway. Eight proteins form a nuclear complex, whose integriry is required for the monoubiquitination of two other FA proteins, FANCD2 and FANCI, in response to DNA replication stress. Despite intensive research, the function of the FA/BRCA pathway at a molecular level has remained largely elusive so far. At the beginning of my thesis, we therefore decided to purify the proteins of the FA core complex and to investigate their biochemical properties. We started with the five proteins which were known at that time, FANCA, FANCC, FANCE, FANCF, and FACG. Later on, we extended our studies to the newly discovered proteins FANCL, FANCM, and FAAP24, and eventually focused our work on the characterisation of FANCM. In contrast to the other core complex proteins, FANCM contains two conserved domains, which point to a role in DNA metabolism: an N-terminal DEAH box helicase domain and a C-terminal ERCC4 nuclease domain. In this study, we have successfully purified full-length FANCM from a recombinant source. We show that purified FANCM binds to branched DNA molecules, such as Holliday junctions and replication forks, with high specificity and affinity. In addition, we demonstrate that FANCM can translocate the junction point of branched DNA molecules due to its helicase domain in an ATPase-dependent manner. FANCM can even dissociate large recombination intermediates, via branch migration of Holliday junctions through a 2.6 kb region of homology. Taken together, our data suggest that FANCM can specifically bind to replication forks and Holliday junctions in vitro, and that its DEAH box helicase domain is associated with a potent branch migration activity. We propose that FANCM might have a direct role in the processing of DNA replication intermediates. This is consistent with the current view that FA proteins coordinate DNA repair at stalled replication forks. Our findings provide a first hint as to the context in which FANCM might play a role in the cell. We are optimistic that they might be key to further elucidate the function of a pathway which is far from being understood.

Telomere fluorescence measurements in granulocytes and T lymphocyte subsets point to a high turnover of hematopoietic stem cells and memory T cells in early childhood.

To study telomere length dynamics in hematopoietic cells with age, we analyzed the average length of telomere repeat sequences in diverse populations of nucleated blood cells. More than 500 individuals ranging in age from 0 to 90 yr, including 36 pairs of monozygous and dizygotic twins, were analyzed using quantitative fluorescence in situ hybridization and flow cytometry. Granulocytes and naive T cells showed a parallel biphasic decline in telomere length with age that most likely reflected accumulated cell divisions in the common precursors of both cell types: hematopoietic stem cells. Telomere loss was very rapid in the first year, and continued for more than eight decades at a 30-fold lower rate. Memory T cells also showed an initial rapid decline in telomere length with age. However, in contrast to naive T cells, this decline continued for several years, and in older individuals lymphocytes typically had shorter telomeres than did granulocytes. Our findings point to a dramatic decline in stem cell turnover in early childhood and support the notion that cell divisions in hematopoietic stem cells and T cells result in loss of telomeric DNA.

Infections pulmonaires : le point de vue du radiologue [Pulmonary infections: the radiologist's point of view]

La place de l'imagerie est essentielle au cours des infections pulmonaires. La TDM doit être effectuée en cas de forte suspicion clinique de pneumonie avec aspect radiographique normal, équivoque ou non spécifique, ce qui concerne particulièrement les sujets immunodéprimés. Elle permet de détecter les anomalies associées ou une affection sous-jacente, d'orienter un lavage broncho-alvéolaire ou de guider une biopsie pulmonaire percutanée ou transbronchique. Les expressions d'un germe peuvent varier selon le degré d'immunodépression. Il en est ainsi pour la tuberculose au cours du sida. Les germes impliqués varient selon le type d'immunodépression, certaines infections pouvant engager rapidement le pronostic vital. Le spectre radiologique de l'aspergillose pulmonaire, complexe, doit être connu, ce diagnostic devant être proposé dans des conditions particulières.

Sentence des juge et consuls de Paris ; qui condamne à payer deux lettres de change adhirées, quoiqu'elles ne soient point revêtues des signatures du tireur et de l'endosseur

[Acte. 1776-03-13. Paris]

Audit report on the City of Center Point, Iowa for the year ended June 30, 2014

Audit report on the City of Center Point, Iowa for the year ended June 30, 2014

Mise au point concernantl'utilisation du dosagede l'antigène carcino-embryonnaire (CEA)en clinique

The carcinoembryonic antigen (CEA) is a tumor marker defined by specific heterologous antisera. Elevated levels of circulating CEA have been detected by radioimmunoassay in 20-90 per cent of cases of colorectal carcinomas depending on the degree of tumor spread. The fact that elevation of CEA level can also be observed in other types of carcinomas and in several non malignant conditions greatly limit the value of the CEA test for the early diagnosis of colorectal carcinoma. Thus, the CEA assay should not be used as a screening test for cancer. Repeatecl CEA mesurements, however, appear to be of importance for the evaluation of tumor resection and the detection of tumor recurrence. The only localized tumors known to produce elevation of CEA above the levels observed in non malignant diseases are carcinomas of the large bowel and the pancreas. In carcinomas derived from other organs a marked increase of CEA level is always associated with the presence of distant metastasis. Therefore at the present time the clinical applications of the CEA radioimmunoassay should be limited to the differentiai diagnosis of patients with suspicion of primary colorectal or pancreatic carcinoma, to the detection of distant metastasis in other types of carcinomas and to the post operative follow up of patients who had elevated levels of CEA before surgery. Well-controlled studies are still needed to determine if therapeutic decisions based on CEA results can lead to improved survival.

Report on the Iowa Judicial Branch for the year ended June 30, 2014

Report on the Iowa Judicial Branch for the year ended June 30, 2014

Report on the Iowa Judicial Branch – County Clerks of District Courts, a part of the State of Iowa, for the year ended June 30, 2014

Report on the Iowa Judicial Branch – County Clerks of District Courts, a part of the State of Iowa, for the year ended June 30, 2014

Iowa Child Advocacy Board Recommendations to the Iowa Judicial Branch, February 15, 2008

The Iowa Child Advocacy Board (ICAB) is an independent board composed of nine members appointed by the Governor of Iowa and confirmed by the Iowa Senate. This report is about recommendations to the Iowa Judicial Branch.

The branch-site test of positive selection is surprisingly robust but lacks power under synonymous substitution saturation and variation in GC

Positive selection is widely estimated from protein coding sequence alignments by the nonsynonymous-to-synonymous ratio omega. Increasingly elaborate codon models are used in a likelihood framework for this estimation. Although there is widespread concern about the robustness of the estimation of the omega ratio, more efforts are needed to estimate this robustness, especially in the context of complex models. Here, we focused on the branch-site codon model. We investigated its robustness on a large set of simulated data. First, we investigated the impact of sequence divergence. We found evidence of underestimation of the synonymous substitution rate for values as small as 0.5, with a slight increase in false positives for the branch-site test. When dS increases further, underestimation of dS is worse, but false positives decrease. Interestingly, the detection of true positives follows a similar distribution, with a maximum for intermediary values of dS. Thus, high dS is more of a concern for a loss of power (false negatives) than for false positives of the test. Second, we investigated the impact of GC content. We showed that there is no significant difference of false positives between high GC (up to similar to 80%) and low GC (similar to 30%) genes. Moreover, neither shifts of GC content on a specific branch nor major shifts in GC along the gene sequence generate many false positives. Our results confirm that the branch-site is a very conservative test.

Oral flurbiprofen metabolic ratio assessment using a single-point dried blood spot.

We investigated whether a single blood measurement using the minimally invasive technique of a finger prick to draw a blood sample of 5 µl (to yield a dried blood spot (DBS)) is suitable for the assessment of flurbiprofen (FLB) metabolic ratio (MR). Ten healthy volunteers who had been genotyped for CYP2C9 were recruited as subjects. They received FLB alone in session 1 and FLB with fluconazole in session 2. In session 3, the subjects were pretreated for 4 days with rifampicin and received FLB with the last dose of rifampicin on day 5. Plasma and DBS samples were obtained between 0 and 8 h after FLB administration, and urine was collected during the 8 h after administration. The pharmacokinetic profiles of the drugs were comparable in DBS and plasma. FLB's apparent clearance values decreased by 35% in plasma and DBS during session 2 and increased by 75% in plasma and by 30% in DBS during session 3. Good correlations were observed between MRs calculated from urine, plasma, and DBS samples.