900 resultados para insertion sites


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This report presents systematic empirical annotation of transcript products from 399 annotated protein-coding loci across the 1% of the human genome targeted by the Encyclopedia of DNA elements (ENCODE) pilot project using a combination of 5' rapid amplification of cDNA ends (RACE) and high-density resolution tiling arrays. We identified previously unannotated and often tissue- or cell-line-specific transcribed fragments (RACEfrags), both 5' distal to the annotated 5' terminus and internal to the annotated gene bounds for the vast majority (81.5%) of the tested genes. Half of the distal RACEfrags span large segments of genomic sequences away from the main portion of the coding transcript and often overlap with the upstream-annotated gene(s). Notably, at least 20% of the resultant novel transcripts have changes in their open reading frames (ORFs), most of them fusing ORFs of adjacent transcripts. A significant fraction of distal RACEfrags show expression levels comparable to those of known exons of the same locus, suggesting that they are not part of very minority splice forms. These results have significant implications concerning (1) our current understanding of the architecture of protein-coding genes; (2) our views on locations of regulatory regions in the genome; and (3) the interpretation of sequence polymorphisms mapping to regions hitherto considered to be "noncoding," ultimately relating to the identification of disease-related sequence alterations.

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Many diurnal bird species roost at night in holes. As a regular visitor of a hole they are therefore a welcome host for several species of ectoparasites. The interactions of ectoparasites with the behaviour, life-history traits and population demography of their hosts are largely unknown. In the present study the effects of the haematophagous hen flea, Ceratophyllus gallinae , on the great tit's choice of winter roost site were investigated experimentally. Three experiments tested (1) whether great tits prefer a clean nestbox to one containing an old, but parasite-free nest, (2) whether they prefer a parasite-free nestbox to one infested with the haematophagous hen flea, and (3) whether they prefer not to use a nestbox when there is only an infested box available in their territory. In the first experiment there was no discrimination and both kinds of boxes were used equally often. In the second experiment the great tits clearly preferred to roost in the box without ectoparasites. In the third experiment a significantly higher proportion of the infested nestboxes were not used for roosting compared with the parasite-free boxes. Recently the validity of the conclusions drawn from nestbox studies where the naturally occurring detrimental ectoparasites are eliminated by the routine removal of old nests between breeding seasons has been questioned. This study shows that ectoparasites affect host behaviour and therefore lends support to that criticism.

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RESUME« L'insertion sociale plurielle des femmes cadres supérieurs en Suisse. Contribution à l'étude du bien-être subjectif au quotidien. Approche intégrative qualitative. »Depuis une quarantaine d'années, nombreux sont les travaux qui étudient les relations entre les différents milieux de vie au quotidien et, plus particulièrement, l'impact de leurs articulations singulières sur la santé. Nous y identifions deux axes principaux : l'un aborde ce phénomène selon une perspective de « conflit travail-famille » en termes de « stress », l'autre se focalise davantage sur la promotion du « bien-être » au travers d'une approche d'« équilibre travail-vie ». Or, l'ensemble de ces recherches considère comme «pathogènes» les désajustements, les contradictions et les tensions vécus au quotidien. Selon cette tendance, le « bien-être » apparaît comme un état d'équilibre ultime indépendant du contexte de vie du sujet. Toutefois, peu de recherches portent sur la dimension située du bien-être dans son rapport à l'activité concrète au sein des milieux deNotre étude s'intéresse à cette question auprès des femmes cadres supérieurs, selon une perspective critique et développementale en psychologie de la santé (Lyons & Chamberlain, 2006 ; Santiago-Delefosse, 2002,2011 ; Malrieu, 1989 ; Vygotski, 1985). En effet, cette population constitue un terrain privilégié pour comprendre le sens donné à l'activité à partir des contraintes, responsabilités et demandes perçues dans des contextes parfois contradictoires, et pour analyser le rôle de ces derniers dans un bien-être subjectif.En cohérence avec notre positionnement théorique, nous avons mené des entretiens qualitatifs focalisés sur l'activité quotidienne auprès de 20 femmes, et ceci en deux temps (T1-T2) (40 entretiens). Les résultats issus des analyses du contenu des discours permettent de définir le vécu de l'articulation des milieux de vie chez nos participantes, selon trois axes à la fois interdépendants et autonomes. Chaque axe se définit par une série de supports spécifiques jouant un rôle structurant dans leur bien-être subjectif. Ainsi, le premier axe se caractérise par des supports de maîtrise subjective, ainsi que par l'appropriation de contraintes sociales et corporelles, selon un rythme de l'activité soutenu. Le deuxième s'accompagne de supports qui favorisent la prise de distance au travers du relâchement du rythme et du lâcher prise de la maîtrise, par la création d'espaces personnels et sociaux « pour soi ». Enfin, le troisième porte sur le positionnement de soi par rapport à autrui en termes de « personnalisation ».Construits en rapport à la corporéité et à autrui au sein de contextes spécifiques, ces différents supports prennent leur sens au sein d'un système de pratiques global, unique pour chaque femme. Selon cette conception critique, le bien-être subjectif chez les femmes cadres se définit comme le fruit d'un processus mouvant issu des tensions vécues entre les trois axes de l'articulation des milieux de vie. Il est par conséquent social, corporel et psychologique.Nos résultats ouvrent des perspectives de recherche et d'intervention, notamment en santé et travail. Ces ouvertures sont orientées vers une approche intégrative en psychologie de la santé, c'est-à-dire, de la prise en compte dans des questions de santé et de bien-être du processus de construction du sujet en relation à son insertion sociale plurielle.ABSTRACT« Plural social participation among women senior managers in Switzerland. Contribution to the study of subjective well-being in everyday life. An integrative and qualitativeapproach.»For the last forty years, a large body of literature has studied the relationships between different social realms in everyday life and, more particularly, the impact of their singular intertwinements with health. We identify two main trends : The first one focuses on this phenomenon through the « work-family conflict » perspective in terms of « stress » whilst the second one is more concerned by the promotion of « well-being » through a « work-life balance » approach. However, both of these trends consider disadjustments, contradictions and tensions in everyday life as « pathogenic ». According to this conception, « well- being » appears as an ultimate state of balance which is indépendant from the subject's life context. Nevertheless, few studies have examined the situated dimension of well-being in its link to concrete activity in social realms.Our research is concerned with this issue among women senior managers from a critical and developmental perspective in Health Psychology (Lyons & Chamberlain, 2006 ; Santiago-Delefosse, 2002, 2011 ; Malrieu, 1989 ; Vygotski, 1985). In fact, this population represents a favourable field so as to study : how the meaning of daily activity is constructed accross different and often conflictive social realms ; to understand the many ways in which this population deals with perceived constraints, responsibilities and requests, and to analyse the role of situated plural activity in subjective well-being.Consitent with our theoretical framework, we have designed a qualitative method. We have conducted two-time (T1-T2) interviews with 20 women by focusing on their daily activity (40 interviews). The Thematic Content Analysis reveals that four different social realms are articulated among our participants through three main axes, which are at the same time interdependent and autonomous. Each one of these axis is defined by a certain number of specific supports that play an important role in these women's subjective well- being. The first axis is concerned by several supports that signify a « feeling of control » along with the appropriation of social and body constraints by means of a rapid pace of activity. The second one regards the use of supports that contribute to « put things into perspective » by means of the slowing down of the pace of activity and through letting go of the feeling of control. This mechanism includes the creation of personal and social spaces of « one's own ». The third axis is defined by the positioning of the self in regard to others through a process of « personnalization ».Developed in specific contexts through the intertwinnements between the body and social others, supports belonging to these axes acquire significance and meaning on the basis of their relationship to a global system of activities of which they are part. However, this articulation is uniquely defined for each participant. According to this critical approach, subjective well-being among women senior managers emerges as a meaningful and changing process, situated in a plural social context. This is, it appears as the result of conflictual interactions defining the three different axis that we have identified. Subjective well-being is hence a social, embodied and psychological phenomena that is closely linked to the articulation of different social realms. Our findings open new research and practice perspectives, especially concerning health and work issues. These perspectives convey an integrative approach in Health Psychology by considering health and well-being by taking into account the process of construction of the subject in regard to his or her plural social participation.

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Despite the key importance of altered oceanic mantle as a repository and carrier of light elements (B, Li, and Be) to depth, its inventory of these elements has hardly been explored and quantified. In order to constrain the systematics and budget of these elements we have studied samples of highly serpentinized (>50%) spinel harzburgite drilled at the Mid-Atlantic Ridge (Fifteen-Twenty Fracture zone, ODP Leg 209, Sites 1272A and 1274A). In-situ analysis by secondary ion mass spectrometry reveals that the B, Li and Be contents of mantle minerals (olivine, orthopyroxene, and clinopyroxene) remain unchanged during serpentinization. B and Li abundances largely correspond to those of unaltered mantle minerals whereas Be is close to the detection limit. The Li contents of clinopyroxene are slightly higher (0.44-2.8 mu g g(-1)) compared to unaltered mantle clinopyroxene, and olivine and clinopyroxene show an inverse Li partitioning compared to literature data. These findings along with textural observations and major element composition obtained from microprobe analysis suggest reaction of the peridotites with a mafic silicate melt before serpentinization. Serpentine minerals are enriched in B (most values between 10 and 100 mu g g(-1)), depleted in Li (most values below I mu g g(-1)) compared to the primary phases, with considerable variation within and between samples. Be is at the detection limit. Analysis of whole rock samples by prompt gamma activation shows that serpentinization tends to increase B (10.4-65.0 mu g g(-1)), H2O and Cl contents and to lower Li contents (0.07-3.37 mu g g(-1)) of peridotites, implying that-contrary to alteration of oceanic crust-B is fractionated from Li and that the B and Li inventory should depend essentially on rock-water ratios. Based on our results and on literature data, we calculate the inventory of B and Li contained in the oceanic lithosphere, and its partitioning between crust and mantle as a function of plate characteristics. We model four cases, an ODP Leg 209-type lithosphere with almost no igneous crust, and a Semail-type lithosphere with a thick igneous crust, both at I and 75 Ma, respectively. The results show that the Li contents of the oceanic lithosphere are highly variable (17-307 kg in a column of I m x I m x thickness of the lithosphere (kg/col)). They are controlled by the primary mantle phases and by altered crust, whereas the B contents (25-904 kg/col) depend entirely on serpentinization. In all cases, large quantities of B reside in the uppermost part of the plate and could hence be easily liberated during slab dehydration. The most prominent input of Li into subduction zones is to be expected from Semail-type lithosphere because most of the Li is stored at shallow levels in the plate. Subducting an ODP Leg 209-type lithosphere would mean only very little Li contribution from the slab. Serpentinized mantle thus plays an important role in B recycling in subduction zones, but it is of lesser importance for Li. (C) 2008 Elsevier Ltd. All rights reserved.

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The effects of the thyroid hormones on target cells are mediated through nuclear T3 receptors. In the peripheral nervous system, nuclear T3 receptors were previously detected with the monoclonal antibody 2B3 mAb in all the primary sensory neurons throughout neuronal life and in peripheral glia at the perinatal period only (Eur. J. Neurosci. 5, 319, 1993). To determine whether these nuclear T3 receptors correspond to functional ones able to bind T3, cryostat sections and in vitro cell cultures of dorsal root ganglion (DRG) or sciatic nerve were incubated with 0.1 nM [125I]-labeled T3, either alone to visualize the total T3-binding sites or added with a 10(3) fold excess of unlabeled T3 to estimate the part due to the non-specific T3-binding. After glutaraldehyde fixation, radioautography showed that the specific T3-binding sites were largely prevalent. The T3-binding capacity of peripheral glia in DRG and sciatic nerve was restricted to the perinatal period in vivo and to Schwann cells cultured in vitro. In all the primary sensory neurons, specific T3-binding sites were disclosed in foetal as well as adult rats. The detection of the T3-binding sites in the nucleus indicated that the nuclear T3 receptors are functional. Moreover the concomitant presence of both T3-binding sites and T3 receptors alpha isoforms in the perikaryon of DRG neurons infers that: 1) [125I]-labeled T3 can be retained on the T3-binding 'E' domain of nascent alpha 1 isoform molecules newly-synthesized on the perikaryal ribosomes; 2) the alpha isoforms translocated to the nucleus are modified by posttranslational changes and finally recognized by 2B3 mAb as nuclear T3 receptor. In conclusion, the radioautographic visualization of the T3-binding sites in peripheral neurons and glia confirms that the nuclear T3 receptors are functional and contributes to clarify the discordant intracellular localization provided by the immunocytochemical detection of nuclear T3 receptors and T3 receptor alpha isoforms.

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At mucosal surfaces, we must co-exist with a high density of diverse microorganisms; therefore, protection against these occurs on multiple levels. Leukocyte- and epithelial derived-antimicrobial peptides and proteins (AMPs) comprise an essential component of immune defense. These molecules possess antibacterial, antifungal and signalling properties and probably contribute to defence and maintenance of homeostasis between the host and commensal microorganisms. Among these AMPs is bactericidal/permeability-increasing protein (BPI), an antimicrobial protein with potent endotoxin-neutralising activity, and several homologs. This review explores the roles of BPI and and its homologs at the mucosal interface. Congeners of BPI are under biopharmaceutical development as novel anti-infective agents, highlighting the potential therapeutic relevance of this protein family.

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Tat activates transcription by interacting with Sp1, NF-kappaB, positive transcription elongation factor b, and trans-activator-responsive element (TAR). Tat and Sp1 play major roles in transcription by protein-protein interactions at human immunodeficiency virus, type 1 (HIV-1) long terminal repeat. Sp1 activates transcription by interacting with cyclin T1 in the absence of Tat. To disrupt the transcription activation by Tat and Sp1, we fused Sp1-inhibiting polypeptides, zinc finger polypeptide, and the TAR-binding mutant Tat (TatdMt) together. A designed or natural zinc finger and Tat mutant fusion was used to target the fusion to the key regulatory sites (GC box and TAR) on the long terminal repeat and nascent short transcripts to disrupt the molecular interaction that normally result in robust transcription. The designed zinc finger and TatdMt fusions were targeted to the TAR, and they potently repressed both transcription and replication of HIV-1. The Sp1-inhibiting POZ domain, TatdMt, and zinc fingers are key functional domains important in repression of transcription and replication. The designed artificial zinc fingers were targeted to the high affinity Sp1-binding site, and by being fused with TatdMt and POZ domain, they strongly block both Sp1-cyclin T1-dependent transcription and Tat-dependent transcription, even in the presence of excess expressed Tat.

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INTRODUCTION: Quantitative sensory testing (QST) is widely used in human research to investigate the integrity of the sensory function in patients with pain of neuropathic origin, or other causes such as low back pain. Reliability of QST has been evaluated on both sides of the face, hands and feet as well as on the trunk (Th3-L3). In order to apply these tests on other body-parts such as the lower lumbar spine, it is important first to establish reliability on healthy individuals. The aim of this study was to investigate intra-rater reliability of thermal QST in healthy adults, on two sites within the L5 dermatome of the lumbar spine and lower extremity. METHODS: Test-retest reliability of thermal QST was determined at the L5-level of the lumbar spine and in the same dermatome on the lower extremity in 30 healthy persons under 40 years of age. Results were analyzed using descriptive statistics and intraclass correlation coefficient (ICC). Values were compared to normative data, using Z-transformation. RESULTS: Mean intraindividual differences were small for cold and warm detection thresholds but larger for pain thresholds. ICC values showed excellent reliability for warm detection and heat pain threshold, good-to-excellent reliability for cold pain threshold and fair-to-excellent reliability for cold detection threshold. ICC had large ranges of confidence interval (95%). CONCLUSION: In healthy adults, thermal QST on the lumbar spine and lower extremity demonstrated fair-to-excellent test-retest reliability.

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In cells, DNA is routinely subjected to significant levels of bending and twisting. In some cases, such as under physiological levels of supercoiling, DNA can be so highly strained, that it transitions into non-canonical structural conformations that are capable of relieving mechanical stress within the template. DNA minicircles offer a robust model system to study stress-induced DNA structures. Using DNA minicircles on the order of 100 bp in size, we have been able to control the bending and torsional stresses within a looped DNA construct. Through a combination of cryo-EM image reconstructions, Bal31 sensitivity assays and Brownian dynamics simulations, we have been able to analyze the effects of biologically relevant underwinding-induced kinks in DNA on the overall shape of DNA minicircles. Our results indicate that strongly underwound DNA minicircles, which mimic the physical behavior of small regulatory DNA loops, minimize their free energy by undergoing sequential, cooperative kinking at two sites that are located about 180° apart along the periphery of the minicircle. This novel form of structural cooperativity in DNA demonstrates that bending strain can localize hyperflexible kinks within the DNA template, which in turn reduces the energetic cost to tightly loop DNA.

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INTRODUCTION. Multimodal strategy targeted at prevention of catheter-related infection combine education to general measures of hygiene with specific guidelines for catheter insertion and dressing (1). OBJECTIVES. In this context, we tested the introduction of chlorhexidine(CHX)-impregnated sponges (2). METHODS. In our 32-beds mixed ICU, prospective surveillance of primary bacteremia and of microbiologically documented catheter-related bloodstream infections (CRBSI) is performed according to standardized definitions. New guidelines for central venous catheter (CVC) dressing combined a CHX-impregnated sponge (BioPatch_) with a transparent occlusive dressing (Tegaderm _) and planning for refection every 7 days. To contain costs, Biopatch_ was used only for internal jugular and femoral sites. Other elements of the prevention were not modified (overall compliance to hand hygiene 65-68%; non coated catheters except for burned patients [173 out of 9,542 patients];maximal sterile barriers for insertion; alcoholic solution ofCHXfor skin disinfection). RESULTS. Median monthly CVC-days increased from 710, to 749, 855 and 965 in 2006, 2007, 2008 and 2009, respectively (p\0.01). Following introduction of the new guidelines (4Q2007), the average monthly rate of infections decreased from 3.7 (95% CI: 2.6-4.8) episodes/1000 CVC-days over the 24 preceding months to 2.2 (95% CI: 1.5-2.8) over the 24 following months (p = 0.031). Dressings needed to be changed every 3-4 days. The decrease of catheter-related infections we observed in all consecutive admitted patients is comparable to that recently showed in a placeborandomized trial2. Further generalization to all CVC and arterial catheters access may be justified. CONCLUSIONS. Our data strongly suggest that combined with occlusive dressings, CHXimpregnated sponges for dressing of all CVC catheters inserted in internal jugular and/or femoral sites, significantly reduces the rate of primary bacteremia and CRBSI. REFERENCES. (1) Eggimann P, Harbarth S, Constantin MN, Touveneau S, Chevrolet JC, Pittet D. Impact of a prevention strategy targeted at vascular-access care on incidence of infections acquired in intensive care. Lancet 2000; 355:1864-1868. (2) Timsit JF, Schwebel C, Bouadma L, Geffroy A, Garrouste-Org, Pease S et al. Chlorhexidine- impregnated sponges and less frequent dressing changes for prevention of catheter-related infections in critically ill adults: a randomized controlled trial. JAMA 2009; 301(12):1231-1241.

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The ability to determine the location and relative strength of all transcription-factor binding sites in a genome is important both for a comprehensive understanding of gene regulation and for effective promoter engineering in biotechnological applications. Here we present a bioinformatically driven experimental method to accurately define the DNA-binding sequence specificity of transcription factors. A generalized profile was used as a predictive quantitative model for binding sites, and its parameters were estimated from in vitro-selected ligands using standard hidden Markov model training algorithms. Computer simulations showed that several thousand low- to medium-affinity sequences are required to generate a profile of desired accuracy. To produce data on this scale, we applied high-throughput genomics methods to the biochemical problem addressed here. A method combining systematic evolution of ligands by exponential enrichment (SELEX) and serial analysis of gene expression (SAGE) protocols was coupled to an automated quality-controlled sequence extraction procedure based on Phred quality scores. This allowed the sequencing of a database of more than 10,000 potential DNA ligands for the CTF/NFI transcription factor. The resulting binding-site model defines the sequence specificity of this protein with a high degree of accuracy not achieved earlier and thereby makes it possible to identify previously unknown regulatory sequences in genomic DNA. A covariance analysis of the selected sites revealed non-independent base preferences at different nucleotide positions, providing insight into the binding mechanism.

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We report a Spanish family with autosomal-dominant non-neuropathic hereditary amyloidosis with a unique hepatic presentation and death from liver failure, usually by the sixth decade. The disease is caused by a previously unreported deletion/insertion mutation in exon 4 of the apolipoprotein AI (apoAI) gene encoding loss of residues 60-71 of normal mature apoAI and insertion at that position of two new residues, ValThr. Affected individuals are heterozygous for this mutation and have both normal apoAI and variant molecules bearing one extra positive charge, as predicted from the DNA sequence. The amyloid fibrils are composed exclusively of NH2-terminal fragments of the variant, ending mainly at positions corresponding to residues 83 and 92 in the mature wild-type sequence. Amyloid fibrils derived from the other three known amyloidogenic apoAI variants are also composed of similar NH2-terminal fragments. All known amyloidogenic apoAI variants carry one extra positive charge in this region, suggesting that it may be responsible for their enhanced amyloidogenicity. In addition to causing a new phenotype, this is the first deletion mutation to be described in association with hereditary amyloidosis and it significantly extends the value of the apoAI model for investigation of molecular mechanisms of amyloid fibrillogenesis.

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White adipose tissue (WAT) is a disperse organ acting as energy storage depot and endocrine/paracrine controlling factor in the management of energy availability and inflammation. WAT sites response under energy-related stress is not uniform. In the present study we have analyzed how different WAT sites respond to limited food restriction as a way to better understand the role of WAT in the pathogenesis of the metabolic syndrome.