Fonctions du plancher pelvien: de la phase expulsive à la consultation du post-partum [Pelvic floor functions: from the beginning of the second phase of labor to the postpartum consultation].

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.

PHE-CRCE-010: Estimating Local Mortality Burdens associated with Particulate Air Pollution

The increase in mortality risk associated with long-term exposure to particulate air pollution is one of the most important, and best-characterised, effects of air pollution on health. This report presents estimates of the size of this effect on mortality in local authority areas in the UK, building upon the attributable fractions reported as an indicator in the public health outcomes framework for England. It discusses the concepts and assumptions underlying these calculations and gives information on how such estimates can be made. The estimates are expected to be useful to health and wellbeing boards when assessing local public health priorities, as well as to others working in the field of air quality and public health. The estimates of mortality burden are based on modelled annual average concentrations of fine particulate matter (PM2.5) in each local authority area originating from human activities. Local data on the adult population and adult mortality rates is also used. Central estimates of the fraction of mortality attributable to long-term exposure to current levels of anthropogenic (human-made) particulate air pollution range from around 2.5% in some local authorities in rural areas of Scotland and Northern Ireland and between 3 and 5% in Wales, to over 8% in some London boroughs. Because of uncertainty in the increase in mortality risk associated with ambient PM2.5, the actual burdens associated with these modelled concentrations could range from approximately one-sixth to about double these figures. Thus, current levels of particulate air pollution have a considerable impact on public health. Measures to reduce levels of particulate air pollution, or to reduce exposure of the population to such pollution, are regarded as an important public health initiative.

Review of methods for estimating life expectancy by social class using the ONS Longitudinal Study

Life expectancy by socio-economic status is an important measure of health inequality. This article presents proposed changes in the methods used to estimate life expectancy by social class using the ONS Longitudinal Study.

Analysis of angiotensin II- and ACTH-driven mineralocorticoid functions and omental adiposity in a non-genetic, hyperadipose female rat phenotype

The hypothalamic damage induced by neonatal treatment with monosodium l-glutamate (MSG) induces several metabolic abnormalities, resulting in a rat hyperleptinemic-hyperadipose phenotype. This study was conducted to explore the impact of the neonatal MSG treatment, in the adult (120 days old) female rat on: (a) the in vivo and in vitro mineralocorticoid responses to ACTH and angiotensin II (AII); (b) the effect of leptin on ACTH- and AII-stimulated mineralocorticoid secretions by isolated corticoadrenal cells; and (c) abdominal adiposity characteristics. Our data indicate that, compared with age-matched controls, MSG rats displayed: (1) enhanced and reduced mineralocorticoid responses to ACTH and AII treatments, respectively, effects observed in both in vivo and in vitro conditions; (2) adrenal refractoriness to the inhibitory effect of exogenous leptin on ACTH-stimulated aldosterone output by isolated adrenocortical cells; and (3) distorted omental adiposity morphology and function. This study supports that the adult hyperleptinemic MSG female rat is characterized by enhanced ACTH-driven mineralocorticoid function, impaired adrenal leptin sensitivity, and disrupted abdominal adiposity function. MSG rats could counteract undesirable effects of glucocorticoid excess, by developing a reduced AII-driven mineralocorticoid function. Thus, chronic hyperleptinemia could play a protective role against ACTH-mediated allostatic loads in the adrenal leptin resistant, MSG female rat phenotype.

Overlapping, additive and counterregulatory effects of type II and I interferons on myeloid dendritic cell functions.

Dendritic cells (DCs) are central player in immunity by bridging the innate and adaptive arms of the immune system (IS). Interferons (IFNs) are one of the most important factors that regulate both innate and adaptive immunity too. Thus, the understanding of how type II and I IFNs modulate the immune-regulatory properties of DCs is a central issue in immunology. In this paper, we will address this point in the light of the most recent literature, also highlighting the controversial data reported in the field. According to the wide literature available, type II as well as type I IFNs appear, at the same time, to collaborate, to induce additive effects or overlapping functions, as well as to counterregulate each one's effects on DC biology and, in general, the immune response. The knowledge of these effects has important therapeutic implications in the treatment of infectious/autoimmune diseases and cancer and indicates strategies for using IFNs as vaccine adjuvants and in DC-based immune therapeutic approaches.

Anti-leishmania effector functions of CD4+ Th1 cells and early events instructing Th2 cell development and susceptibility to Leishmania major in BALB/c mice.

Resistance and susceptibility to infection with the intracellular parasite, Leishmania major, are mediated by parasite-specific CD4+ Th1 and Th2 cells, respectively. It is well established that the protective effect of parasite-specific CD4+ Th1 cells is largely dependent upon the IFN-gamma produced. However, recent results indicate that the effect of Th1 cells on resolution of lesions induced by L. major in genetically resistant mice also requires a functional Fas-FasL pathway of cytotoxicity. In contrast to resistant mice, susceptible BALB/c mice develop aberrant Th2 responses following infection with L. major and consequently suffer progressive disease. These outcomes clearly depends upon the production of interleukin 4 (IL-4) early after infection. We have shown that a burst of IL-4 mRNA, peaking in draining lymph nodes of BALB/c mice 16 hrs after infection, occurs within CD4+ T cells that express V beta 4-V alpha 8 T cell receptors. In contrast to control and V beta 6-deficient mice, V beta 4-deficient BALB/c mice were resistant to infection, demonstrating the role of these cells in Th2 development. The early IL-4 response was absent in these mice, and Th1 responses occurred following infection. The LACK antigen of L. major induced comparable IL-4 production in V beta 4-V alpha 8 CD4+ T cells. Thus, the IL-4 required for Th2 development and susceptibility to L. major is produced by a restricted population of V beta 4-V alpha 8 CD4+ T cells after cognate interaction with a single antigen from this complex parasite. The IL-4 produced rapidly by these CD4+ T cells induces within 48 hours a state of unresponsiveness to IL-12 among parasite-specific CD4+ T cell precursors by downregulating the IL-12 receptor beta 2 chain expression.

Estimating attributable mortality due to nosocomial infections acquired in intensive care units.

BACKGROUND: The strength of the association between intensive care unit (ICU)-acquired nosocomial infections (NIs) and mortality might differ according to the methodological approach taken. OBJECTIVE: To assess the association between ICU-acquired NIs and mortality using the concept of population-attributable fraction (PAF) for patient deaths caused by ICU-acquired NIs in a large cohort of critically ill patients. SETTING: Eleven ICUs of a French university hospital. DESIGN: We analyzed surveillance data on ICU-acquired NIs collected prospectively during the period from 1995 through 2003. The primary outcome was mortality from ICU-acquired NI stratified by site of infection. A matched-pair, case-control study was performed. Each patient who died before ICU discharge was defined as a case patient, and each patient who survived to ICU discharge was defined as a control patient. The PAF was calculated after adjustment for confounders by use of conditional logistic regression analysis. RESULTS: Among 8,068 ICU patients, a total of 1,725 deceased patients were successfully matched with 1,725 control patients. The adjusted PAF due to ICU-acquired NI for patients who died before ICU discharge was 14.6% (95% confidence interval [CI], 14.4%-14.8%). Stratified by the type of infection, the PAF was 6.1% (95% CI, 5.7%-6.5%) for pulmonary infection, 3.2% (95% CI, 2.8%-3.5%) for central venous catheter infection, 1.7% (95% CI, 0.9%-2.5%) for bloodstream infection, and 0.0% (95% CI, -0.4% to 0.4%) for urinary tract infection. CONCLUSIONS: ICU-acquired NI had an important effect on mortality. However, the statistical association between ICU-acquired NI and mortality tended to be less pronounced in findings based on the PAF than in study findings based on estimates of relative risk. Therefore, the choice of methods does matter when the burden of NI needs to be assessed.

Estimating the incidence of cancers in Switzerland: 1983-1987.

Estimates have recently been made of the incidence of cancers in the countries of the European Community. Similar estimates are given for Switzerland, based on data from the six Swiss cantonal cancer registries, all of which have been operating for at least 12 years. These registries cover Basel, Geneva, Neuchatel, St Gall and Appenzell, Vaud and Zurich, which account for about 50% of the Swiss population as a whole. Two different methods were used to extrapolate from the incidences observed in the regions covered by cancer registration to the entire country. The first method is based solely on the distribution of populations according to the country's main linguistic groups, whereas the second relies on mortality data. Estimates obtained by the second approach are presented and their reliability is discussed. Comparison of the age incidence curve with that of Denmark tends to confirm the validity of the estimations. Estimated standardised rates (world population) for all sites except nonmelanomatous skin cancer are 294.3 for males and 214.2 for females. Comparisons with other European countries show that in males, lung cancer is relatively less common in Switzerland, whereas in females, breast cancer is relatively more frequent.

Transnational study of roles/functions and associated ICT competencies for Higher Education teachers

Aquest estudi forma part del projecte eLene-TLC1 Virtual Campus (2007-2008) recolzat pel programa eLearning de la Comissió Europea. L'objectiu d'aquest projecte és que els professors i els estudiants facin el millor ús possible de les TIC en l'educació superior, preparant als professors per als estudiants de la generació xarxa, permetent als estudiants a la transferència de coneixements i pràctiques de la vida quotidiana per al seu aprenentatge i estimular tant la integració plena de pràctiques innovadores d'ensenyament i d'aprenentatge possibilitades per un entorn tecnològic en constant evolució. Per tal de cobrir part d'aquest objectiu general, es va concebre un estudi per examinar les competències en TIC professors d'Educació Superior en entorns d'aprenentatge en línia.

Comparing methods for dimensionality reduction when data are density functions

Functional Data Analysis (FDA) deals with samples where a whole function is observedfor each individual. A particular case of FDA is when the observed functions are densityfunctions, that are also an example of infinite dimensional compositional data. In thiswork we compare several methods for dimensionality reduction for this particular typeof data: functional principal components analysis (PCA) with or without a previousdata transformation and multidimensional scaling (MDS) for diferent inter-densitiesdistances, one of them taking into account the compositional nature of density functions. The difeerent methods are applied to both artificial and real data (householdsincome distributions)

Hilbert space on probability density functions with Aitchison geometry

Compositional data analysis motivated the introduction of a complete Euclidean structure in the simplex of D parts. This was based on the early work of J. Aitchison (1986) and completed recently when Aitchinson distance in the simplex was associated with an inner product and orthonormal bases were identified (Aitchison and others, 2002; Egozcue and others, 2003). A partition of the support of a random variable generates a composition by assigning the probability of each interval to a part of the composition. One can imagine that the partition can be refined and the probability density would represent a kind of continuous composition of probabilities in a simplex of infinitely many parts. This intuitive idea would lead to a Hilbert-space of probability densitiesby generalizing the Aitchison geometry for compositions in the simplex into the set probability densities

Genetic investigation of the functions of c-Myc and N-Myc in Hematopoietic stem cells

Résumé : c-Myc, le premier facteur de transcription de la famille Myc a été découvert il y a maintenant trente ans. Il reste à l'heure actuelle parmi les plus puissants proto-oncogènes connus. c-Myc est dérégulé dans plus de 50% des cancers, où il promeut la prolifération, la croissance cellulaire, et la néoangiogenèse. Myc peut aussi influencer de nombreuses autres fonctions de par sa capacité à activer ou à réprimer la transcription de nombreux gènes, et à agir globalement sur le génome à travers des modifications épigénétiques de la chromatine. La famille d'oncogènes Myc comprend, chez les mammifères, trois protéines structurellement proches: c-Myc, N-Myc et L-Myc. Ces protéines ont les mêmes proprietés biochimiques, exercent les mêmes fonctions mais sont le plus souvent exprimées de façon mutuellement exclusive. Myc a été récemment identifié comme un facteur clef dans la maintenance des cellules souches embryonnaires et adultes ainsi que dans la réacquisition des proprietés des cellules souches. Nous avons précédemment démontré que l'élimination de c-Myc provoque une accumulation de cellules souches hématopoïétiques (CSH) suite à un défaut de différenciation lié à la niche. Les CSH sont responsables de la production de tous les éléments cellulaires du sang pour toute la vie de l'individu et sont définies par leur capacité à s'auto-renouveler tout en produisant des précurseurs hématopoïétiques. Afin de mieux comprendre la fonction de Myc dans les CSH, nous avons choisi de combiner l'utilisation de modèles de souris génétiquement modifiées à une caractérisation systématique des schémas d'expression de c-Myc, N-Myc et L-Myc dans tout le système hématopoïétique. Nous avons ainsi découvert que les CSH les plus immatures expriment des quantités équivalentes de transcrits de c-myc et N-myc. Si les CSH déficientes en N-myc seulement ont une capacité d'auto-renouvellement à long-terme réduite, l'invalidation combinée des gènes c-myc et N-myc conduit à une pan-cytopénie suivie d'une mort rapide de l'animal, pour cause d'apoptose de tous les types cellulaires hématopoïétiques. En particulier, les CSH en cours d'auto-renouvelemment, mais pas les CSH quiescentes, accumulent du Granzyme B (GrB), une molécule fortement cytotoxique qui provoque une mort cellulaire rapide. Ces données ont ainsi mis au jour un nouveau mécanisme dont dépend la survie des CSH, à savoir la répression du GrB, une enzyme typiquement utilisée par le système immunitaire inné pour éliminer les tumeurs et les cellules infectées par des virus. Dans le but d'évaluer l'étendue de la redondance entre c-Myc et N-Myc dans les CSH, nous avons d'une part examiné des souris dans lesquelles les séquences codantes de c-myc sont remplacées par celles de N-myc (NCR) et d'autre part nous avons géneré une série allèlique de myc en éliminant de façon combinatoire un ou plusieurs allèles de c-myc et/ou de N-myc. Alors que l'analyse des souris NCR suggère que c-Myc et N-Myc sont qualitativement redondants, la série allélique indique que les efficiences avec lesquelles ces deux protéines influencent des procédés essentiels à la maintenance des CSH sont différentes. En conclusion, nos données génétiques montrent que l'activité générale de MYC, fournie par c-Myc et N-Myc, contrôle plusieurs aspects cruciaux de la fonction des CSH, notamment l'auto-renouvellement, la survie et la différenciation. Abstract : c-Myc, the first Myc transcription factor was discovered 30 years ago and is to date one of the most potent proto-oncogenes described. It is found to be misregulated in over 50% of all cancers, where it drives proliferation, cell growth and neo-angiogenesis. Myc can also influence a variety of other functions, owing to its ability to activate and repress transcription of many target genes and to globally regulate the genome via epigenetic modifications of the chromatin. The Myc family of oncogenes consists of three closely related proteins in mammals: c-Myc, N-Myc and L-Myc. These proteins share the same biochemical properties, exert mostly the same functions, but are most often expressed in mutually exclusive patterns. Myc is now emerging as a key factor in maintenance of embryonic and adult stem cells as well as in reacquisition of stem cell properties, including induced reprogramming. We previously showed that c-Myc deficiency can cause the accumulation of hematopoietic stem cells (HSCs) due to a niche dependent differentiation defect. HSCs are responsible for life-long replenishment of all blood cell types, and are defined by their ability to self-renew while concomitantly giving rise to more commited progenitors. To gain further insight into the function of Myc in HSCs, in this study we combine the use of genetically-modified mouse models with the systematic characterization of c-myc, N-myc and L-myc transcription patterns throughout the hematopoietic system. Interestingly, the most immature HSCs express not only c-myc, but also about equal amounts of N-myc transcripts. Although conditional deletion of N-myc alone in the bone marrow does not affect steady-state hematopoiesis, N-myc null HSCs show impaired long-term self-renewal capacity. Strikingly, combined deficiency of c-Myc and N-Myc results in pan-cytopenia and rapid lethality, due to the apoptosis of most hematopoietic cell types. In particular, self-renewing HSCs, but not quiescent HSCs or progenitor cell types rapidly up-regulate and accumulate the potent cytotoxic molecule GranzymeB (GrB), causing their rapid cell death. These data uncover a novel pathway on which HSC survival depends on, namely repression of GrB, a molecule typically used by the innate immune system to eliminate tumor and virus infected cells. To evaluate the extent of redundancy between c-Myc and N-Myc in HSCs, we examined mice in which c-myc coding sequences are replaced by that of N-myc (NCR) and also generated an allelic series of myc, by combinatorially deleting one or several c-myc and/or N-myc alleles. While the analysis of NCR mice suggests that c-Myc and N-Myc are qualitatively functionally redundant, our allelic series indicates that the efficiencies with which these two proteins affect crucial HSC maintenance processes are likely to be distinct. Collectively, our genetic data show that general "MYC" activity delivered by c-Myc and N-Myc controls crucial aspects of HSC function, including self-renewal, survival and niche dependent differentiation.

Novel functions of the polymeric Ig receptor: well beyond transport of immunoglobulins.

The polymeric Ig receptor (pIgR) ensures efficient secretion of polymeric IgA (pIgA) at mucosal surfaces. On basal to apical transport across epithelial cells, the pIgR extracellular domain is cleaved, releasing secretory component (SC) in association with pIgA. This finds its raison d'être in the recent observation that SC is directly involved in the protective function of secretory IgA. In addition, free SC exhibits scavenger properties with respect to enteric pathogens. However, although pIgR dedicates its life to mucosal protection, it also seems to permit pathogen entrance through the epithelial barrier. The multiple mechanisms that they are involved in make pIgR and SC instrumental to mucosal immunity.

Estimating the motion of an underwater robot from a monocular image sequence

When underwater vehicles perform navigation close to the ocean floor, computer vision techniques can be applied to obtain quite accurate motion estimates. The most crucial step in the vision-based estimation of the vehicle motion consists on detecting matchings between image pairs. Here we propose the extensive use of texture analysis as a tool to ameliorate the correspondence problem in underwater images. Once a robust set of correspondences has been found, the three-dimensional motion of the vehicle can be computed with respect to the bed of the sea. Finally, motion estimates allow the construction of a map that could aid to the navigation of the robot