189 resultados para 312.235


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BACKGROUND: Obesity and African American ethnicity are established independent risk factors for the development of chronic kidney disease. No data exist about the association between obesity and renal hemodynamics in the African region. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: 301 nondiabetic participants (97 lean, 108 overweight, and 96 obese) of African descent with a positive family history of hypertension from the Seychelles islands. PREDICTOR: Body mass index (BMI). OUTCOMES: Glomerular hyperfiltration, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), and filtration fraction. MEASUREMENTS: GFR and ERPF were measured using inulin and para-aminohippurate clearances, respectively. Participants' baseline demographics, laboratory data, and blood pressure were measured using standard techniques. RESULTS: The prevalence of glomerular hyperfiltration (defined as GFR >or=140 mL/min) increased across BMI categories (7.2%, 14.8%, and 27.1% for lean, overweight, and obese participants, respectively; P < 0.001). Higher BMI was associated with higher median GFR (99, 110, and 117 mL/min for lean, overweight, and obese participants, respectively; P < 0.001), ERPF (424, 462, and 477 mL/min, respectively; P = 0.01), and filtration fraction (0.23, 0.24, and 0.25; P < 0.001). Multivariate analyses adjusting for age, sex, blood pressure, fasting glucose level, and urinary sodium excretion and accounting for familial correlations confirmed the associations between high BMI (>25 kg/m(2)) and increased GFR, ERPF, and filtration fraction. No association between BMI categories and GFR was found with adjustment for body surface area. LIMITATIONS: Participants had a positive family history of hypertension. CONCLUSION: Overweight and obesity are associated with increased GFR, ERPF, and filtration fraction and a high prevalence of glomerular hyperfiltration in nondiabetic individuals of African descent. The absence of associations between BMI categories and GFR indexed for body surface area raises questions regarding the appropriateness of indexing GFR for body surface area in overweight populations.

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The pool of mature T cells comprises a heterogeneous mixture of naive and memory CD4(+) and CD8(+) cells. These cells are long lived at a population level but differ markedly in their relative rates of turnover and survival. Here, we review how contact with exogenous stimuli, notably self MHC ligands and various gamma(c) cytokines, plays a decisive role in controlling normal T cell homeostasis.

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Enjeux et contexte : Dans les questions de santé mentale, internet constitue de plus en plus une source d'information pour les personnes souffrant de troubles psychiatriques ainsi que de leurs proches. D'autre part, le trouble obsessionnel compulsif revêt une importance grandissante et bénéficie d'un intérêt croissant en raison de sa fréquence et de la charge qu'il représente pour le patient et pour la société. Les patients souffrant de trouble obsessionnel compulsif, qu'ils soient diagnostiqués ou non, ainsi que leurs proches peuvent être amenés à rechercher une information de bonne qualité sur net sur le sujet. Cette étude vise à évaluer la qualité de l'information issue de l'internet concernant les sites anglophones traitant du trouble obsessionnel compulsif et de comparer les résultats des requêtes en utilisant un moteur de recherche général (Google) à celles obtenues avec un moteur de recherche spécialisé (Omni Medical Search). Des mots-clés relatifs au trouble obsessionnel compulsif ont été introduits dans Google et Omni Medical Search. Les sites retenus ont été évalués selon leur responsabilité, interactivité, lisibilité et la qualité de leur contenu. Le Label HON et la version brève de l'échelle DISCERN ont été utilisés comme indicateurs possibles de la qualité du contenu. Sur les 235 adresses retrouvées, 53 sites retenus ont été analysés. Résultats : La qualité du contenu des sites examinés est relativement bonne. L'utilisation d'un moteur de recherche spécialisé ne constitue pas un avantage par comparaison au moteur général utilisé par la grande majorité des internautes. Un score > 16 de la version brève du DISCERN est associé à une meilleure qualité du contenu. En conclusion : cette étude montre que le contenu des sites web concernant le trouble obsessionnel compulsif est acceptable. L'utilisation d'un moteur de recherche spécialisé n'offre pas d'avantage par rapport à Google. Comme implications pratiques : internet renferme des sites de haute qualité sur le trouble obsessionnel compulsif. L'accès à ces sites ne nécessite pas l'utilisation d'un moteur de recherche spécialisé. En revanche, une discussion entre le patient et le soignant à propos de l'information disponible sur internet demeure indispensable Perspectives : en dépit des limitations de notre étude, on peut dire que l'information contenue dans le web concernant le trouble obsessionnel compulsif est acceptable. Le contenu et la présentation de cette information pourraient être améliorés. Quant à l'internaute qui cherche une information de qualité, il pourrait être guidé par deux éléments : le HON et la version brève du DISCERN.

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Cet article se propose de lire l'AT comme littérature de crise à partir d'un paradigme fourni par la sociologie moderne. Trois attitudes principales caractérisent les réactions intellectuelles face à la situation de crise : l'attitude utopique, l'attitude nostalgique et l'attitude scientifique. Ces trois réactions permettent d'analyser les grands courants idéologiques du peuple hébreu face au drame national de l'Exil babylonien. Pour les prophètes, l'Exil apparaît comme un temps intermédiaire annonçant une ère de salut. Les milieux sacerdotaux présentent le retour aux institutions religieuses passées comme la seule solution à la crise. Les intellectuels de l'école deutéronomiste cherchent à comprendre les raisons du drame de l'Exil sans proposer de solution immédiate. Ces trois courants, caractérisant chacun une des trois attitudes, se retrouvent dans la société juive post-exilique

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RésuméEn agriculture d'énormes pertes sont causées par des champignons telluriques pathogènes tels que Thielaviopsis, Fusarium, Gaeumannomyces et Rhizoctonia ou encore l'oomycète Pythium. Certaines bactéries dites bénéfiques, comme Pseudomonas fluorescens, ont la capacité de protéger les plantes de ces pathogènes par la colonisation de leur racines, par la production de métabolites secondaires possédants des propriétés antifongiques et par l'induction des mécanismes de défenses de la plante colonisée. P. fluorescens CHAO, une bactérie biocontrôle isolée d'un champ de tabac à Payerne, a la faculté de produire un large spectre de métabolites antifongiques, en particulier le 2,4- diacétylphloroglucinol (DAPG), la pyolutéorine (PLT), le cyanure d'hydrogène (HCN), la pyrrolnitrine (PRN) ainsi que des chélateurs de fer.La plante, par sécrétion racinaire, produit des rhizodéposites, source de carbone et d'azote, qui profitent aux populations bactériennes vivant dans la rhizosphere. De plus, certains stresses biotiques et abiotiques modifient cette sécrétion racinaire, en terme quantitatif et qualitatif. De leur côté, les bactéries bénéfiques, améliorent, de façon direct et/ou indirect, la croissance de la plante hôte. De nombreux facteurs biotiques et abiotiques sont connus pour réguler la production de métabolites secondaires chez les bactéries. Des études récentes ont démontré l'importance de la communication entre la plante et les bactéries bénéfiques afin que s'établisse une interaction profitant à chacun des deux partis. Il est ainsi vraisemblable que les populations bactériennes associées aux racines soient capables d'intégrer ces signaux et d'adapter spécifiquement leur comportement en conséquence.La première partie de ce travail de thèse a été la mise au point d'outils basés sur la cytométrie permettant de mesurer l'activité antifongique de cellules bactériennes individuelles dans un environnent naturel, les racines des plantes. Nous avons démontré, grâce à un double marquage aux protéines autofluorescentes GFP et mCherry, que les niveaux d'expression des gènes impliqués dans la biosynthèse des substances antifongiques DAPG, PLT, PRN et HCN ne sont pas les mêmes dans des milieux de cultures liquides que sur les racines de céréales. Par exemple, l'expression de pltA (impliqué dans la biosynthèse du PLT) est quasiment abolie sur les racines de blé mais atteint un niveau relativement haut in vitro. De plus cette étude a mis en avant l'influence du génotype céréalien sur l'expression du gène phlA qui est impliqué dans la biosynthèse du DAPG.Une seconde étude a révélé la communication existant entre une céréale (orge) infectée par le pathogène tellurique Pythium ultimum et P. fluorescens CHAO. Un système de partage des racines nous a permis de séparer physiquement le pathogène et la bactérie bénéfique sur la plante. Cette méthode a donné la possibilité d'évaluer l'effet systémique, causé par l'attaque du pathogène, de la plante sur la bactérie biocontrôle. En effet, l'infection par le phytopathogène modifie la concentration de certains composés phénoliques dans les exsudats racinaires stimulant ainsi l'expression de phi A chez P.fluorescens CHAO.Une troisième partie de ce travail focalise sur l'effet des amibes qui sont des micro-prédateurs présents dans la rhizosphere. Leur présence diminue l'expression des gènes impliqués dans la biosynthèse du DAPG, PLT, PRN et HCN chez P.fluorescens CHAO, ceci en culture liquide et sur des racines d'orge. De plus, des molécules provenant du surnageant d'amibes, influencent l'expression des gènes requis pour la biosynthèse de ces antifongiques. Ces résultats illustrent que les amibes et les bactéries de la rhizosphere ont développé des stratégies pour se reconnaître et adapter leur comportement.La dernière section de ce travail est consacrée à l'acide indole-acétique (LA.A), une phytohormone connue pour son effet stimulateur sur phlA. Une étude moléculaire détaillée nous a démontré que cet effet de l'IAA est notamment modulé par une pompe à efflux (FusPl) et de son régulateur transcriptionnel (MarRl). De plus, les gènes fusPl et marRl sont régulés par d'autres composés phénoliques tels que le salicylate (un signal végétal) et l'acide fusarique (une phytotoxine du pathogène Fusarium).En résumé, ce travail de thèse illustre la complexité des interactions entre les eucaryotes et procaryotes de la rhizosphère. La reconnaissance mutuelle et l'instauration d'un dialogue moléculaire entre une plante hôte et ses bactéries bénéfiques associées? sont indispensables à la survie des deux protagonistes et semblent être hautement spécifiques.SummaryIn agriculture important crop losses result from the attack of soil-borne phytopathogenic fungi, including Thielaviopsis, Fusarium, Gaeumannomyces and Rhizoctonia, as well as from the oomycete Pythium. Certain beneficial microorganisms of the rhizosphere, in particular Pseudomonas fluorescens, have the ability to protect plants against phytopathogens by the intense colonisation of roots, by the production of antifungal exoproducts, and by induction of plant host defences. P. fluorescens strain CHAO, isolated from a tobacco field near Payerne, produces a large array of antifungal exoproducts, including 2,4-diacetylphloroglucinol (DAPG), pyoluteorin (PLT), hydrogen cyanide (HCN), pyrrolnitrin (PRN) and iron chelators. Plants produce rhizodeposites via root secretion and these represent a relevant source of carbon and nitrogen for rhizosphere microorganisms. Various biotic and abiotic stresses influence the quantity and the quality of released exudates. One the other hand, beneficial bacteria directly or indirectly promote plant growth. Biotic and abiotic factors regulate exoproduct production in biocontrol microorganisms. Recent studies have highlighted the importance of communication in establishing a fine-tuned mutualist interaction between plants and their associated beneficial bacteria. Bacteria may be able to integrate rhizosphere signals and adapt subsequently their behaviour.In a first part of the thesis, we developed a new method to monitor directly antifungal activity of individual bacterial cells in a natural environment, i.e. on roots of crop plants. We were able to demonstrate, via a dual-labelling system involving green and red fluorescent proteins (GFP, mCherry) and FACS-based flow cytometry, that expression levels of biosynthetic genes for the antifungal compounds DAPG, PLT, PRN, and HCN are highly different in liquid culture and on roots of cereals. For instance, expression of pltA (involved in PLT biosynthesis) was nearly abolished on wheat roots whereas it attained a relatively high level under in vitro conditions. In addition, we established the importance of the cereal genotype in the expression of phi A (involved in DAPG biosynthesis) in P. fluorescens CHAO.A second part of this work highlighted the systemic communication that exists between biocontrol pseudomonads and plants following attack by a root pathogen. A split-root system, allowing physical separation between the soil-borne oomycete pathogen Phytium ultimum and P. fluorescens CHAO on barley roots, was set up. Root infection by the pathogen triggered a modification of the concentration of certain phenolic root exudates in the healthy root part, resulting in an induction ofphlA expression in P. fluorescens CHAO.Amoebas are micro-predators of the rhizosphere that feed notably on bacteria. In the third part of the thesis, co-habitation of Acanthamoeba castellanii with P. fluorescens CHAO in culture media and on barley roots was found to significantly reduce bacterial expression of genes involved in the biosynthesis of DAPG, PLT, HCN and PRN. Interestingly, molecular cues present in supernatant of A. castelanii induced the expression of these antifungal genes. These findings illustrate the strategies of mutual recognition developed by amoeba and rhizosphere bacteria triggering responses that allow specific adaptations of their behaviour.The last section of the work focuses on indole-3-acetic acid (IAA), a phytohormone that stimulates the expression of phi A. A detailed molecular study revealed that the IAA-mediated effect on phi A is notably modulated by an efflux pump (FusPl) and its transcriptional regulator (MarRl). Remarkably, transcription of fusPl and marRl was strongly upregulated in presence of other phenolic compounds such as salicylate (a plant signal) and fusaric acid (a phytotoxin of the pathogenic fungus Fusarium).To sum up, this work illustrates the great complexity of interactions between eukaryotes and prokaryotes taking place in the rhizosphere niche. The mutual recognition and the establishment of a molecular cross-talk between the host plant and its associated beneficial bacteria are essential for the survival of the two partners and these interactions appear to be highly specific.

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We investigated respiratory responses during film clip viewing and their relation to the affective dimensions of valence and arousal. Seventy-six subjects participated in a study using a between groups design. To begin with, all participants viewed an emotionally neutral film clip. Then, they were presented with one out of four emotional film clips: a positive high-arousal, a positive low-arousal, a negative high-arousal and a negative low-arousal clip. Respiration, skin conductance level, heart rate, corrugator activity and affective judgments were measured. Expiratory time was shorter and inspiratory duty cycle, mean expiratory flow and minute ventilation were larger during the high-arousal clips compared to the low-arousal clips. The pleasantness of the stimuli had no influence on any respiratory measure. These findings confirm the importance of arousal in respiratory responding but also evidence differences in comparison to previous studies using visual and auditory stimuli. [Authors]

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The relationship of rat brain spectrin isoforms to microtubules of newborn and adult animals was studied. Spectrins were minor components in microtubule preparations. The microtubule-associated spectrin is a major calmodulin-binding protein. Radiolabelled brain spectrin(240/235) revealed specific microtubule binding activity in vitro, possibly via a tubulin.

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Concerns have been raised about the use of topical retinoids since the publication of isolated cases of characteristic retinoid embryopathy, originally described after oral use. A collaborative study of the European Network of Teratology Information Services was carried out to evaluate the rate of congenital malformations following first-trimester topical retinoid exposure. A population of 235 exposed pregnant women was compared with 444 controls. No significant differences were observed between groups with regard to the rates of spontaneous abortion (odds ratio [95% confidence interval], 1.5 [0.8-2.7]), minor birth defects (1.3 [0.4-3.7]), and major birth defects (1.8 [0.6-5.4]). No child showed features of retinoid embryopathy. The rate of elective termination in the exposed group was increased 3-fold (3.4 [1.5-7.8]). In conclusion, these results do not suggest an increased risk of retinoid embryopathy. However, according to current knowledge, topical retinoids cannot be advised for use during pregnancy because their risk/benefit ratio remains questionable.

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Enquête auprès de Michel Badré, Dominique Bourg, Jean-René Brunetière, Jean Gadrey, Alain Grandjean, Bernard Perret et Bruno Villalba.

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BACKGROUND: After a peak in the late 1980s, cancer mortality in Europe has declined by ∼10% in both sexes up to the early 2000s. We provide an up-to-date picture of patterns and trends in mortality from major cancers in Europe. METHODS: We analyzed cancer mortality data from the World Health Organization for 25 cancer sites and 34 European countries (plus the European Union, EU) in 2005-2009. We computed age-standardized rates (per 100 000 person-years) using the world standard population and provided an overview of trends since 1980 for major European countries, using joinpoint regression. RESULTS: Cancer mortality in the EU steadily declined since the late 1980s, with reductions by 1.6% per year in 2002-2009 in men and 1% per year in 1993-2009 in women. In western Europe, rates steadily declined over the last two decades for stomach and colorectal cancer, Hodgkin lymphoma, and leukemias in both sexes, breast and (cervix) uterine cancer in women, and testicular cancer in men. In central/eastern Europe, mortality from major cancer sites has been increasing up to the late 1990s/early 2000s. In most Europe, rates have been increasing for lung cancer in women and for pancreatic cancer and soft tissue sarcomas in both sexes, while they have started to decline over recent years for multiple myeloma. In 2005-2009, there was still an over twofold difference between the highest male cancer mortality in Hungary (235.2/100 000) and the lowest one in Sweden (112.9/100 000), and a 1.7-fold one in women (from 124.4 in Denmark to 71.0/100 000 in Spain). CONCLUSIONS: With the major exceptions of female lung cancer and pancreatic cancer in both sexes, in the last quinquennium, cancer mortality has moderately but steadily declined across Europe. However, substantial differences across countries persist, requiring targeted interventions on risk factor control, early diagnosis, and improved management and pharmacological treatment for selected cancer sites.

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Purpose: To compare the performance Glaucoma Quality of Life-15 (GQL-15) Questionnaire, intraocular pressure measurement (IOP Goldmann tonometry) and a measure of visual field loss using Moorfields Motion Displacement Test (MDT) in detecting glaucomatous eyes from a self referred population. Methods: The GQL-15 has been suggested to correlate with visual disability and psychophysical measures of visual function in glaucoma patients. The Moorfields MDT is a multi location perimetry test with 32 white line stimuli presented on a grey background on a standard laptop computer. Each stimulus is displaced between computer frames to give the illusion of "apparent motion". Participants (N=312, 90% older than 45 years; 20.5% family history of glaucoma) self referred to an advertised World Glaucoma Day (March 2009) Jules Gonin Eye Hospital, Lausanne Switzerland. Participants underwent a clinical exam (IOP, slit lamp, angle and disc examination by a general ophthalmologist), 90% completed a GQL-15 questionnaire and over 50% completed a MDT test in both eyes. Those who were classified as abnormal on one or more of the following (IOP >21 mmHg/ GQL-15 score >20/ MDT score >2/ clinical exam) underwent a follow up clinical examination by a glaucoma specialist including imaging and threshold perimetry. After the second examination subjects were classified as "healthy"(H), "glaucoma suspect" (GS) (ocular hypertension and/or suspicious disc, angle closure with SD) or "glaucomatous" (G). Results: One hundred and ten subjects completed all 4 initial examinations; of these 69 were referred to complete the 2nd examination and were classified as; 8 G, 24 GS, and 37 H. MDT detected 7/8 G, and 7/24 GS, with false referral rate of 3.8%. IOP detected 2/8 G and 8/24 GS, with false referral rate of 8.9%. GQL-15 detected 4/8 G, 16/24 GS with a false referral rate of 42%. Conclusions: In this sample of participants attending a self referral glaucoma detection event, the MDT performed significantly better than the GQL-15 and IOP in discriminating glaucomatous patients from healthy subjects. Further studies are required to assess the potential of the MDT as a glaucoma screening tool.

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(1) The common shrew Sorex araneus and Millet's shrew S. coronatus are sibling species.They are morphologically and genetically very similar but do not hybridize. Their parapatric distribution throughout south-western Europe, with a few narrow zones of distributional overlap, suggests that they are in competitive parapatry. (2) Two of these contact zones were studied; there was evidence of coexistence over periods of 2 years as well as habitat segregation. In both zones, the species segregated on litter thickness and humidity variables. (3) A simple analysis of spatial distribution showed that habitats visible in the field corresponded to the habitats selected by the species. Habitat selection was found throughout the annual life-cycle of the shrews. (4) In one contact zone, a removal experiment was performed to test whether habitat segregation is induced by interspecific interactions. The experiment showed that the species select habitats differentially when both are present and abandon habitat selection when their competitor is removed. (5) These results confirm the role of resource partitioning in promoting narrow rangesof distributional overlap between such parapatric species and qualitatively support the prediction of habitat selection theory that, in a two-species system, coexistence may be achieved by differential habitat selection to avoid competition. The results also support the view that the common shrew and Millet's shrew are in competitive parapatry.