60 research outputs found

    PrCYP707A1, an ABA catabolic gene, is a key component of Phelipanche ramosa seed germination in response to the strigolactone analogue GR24

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    After a conditioning period, seed dormancy in obligate root parasitic plants is released by a chemical stimulus secreted by the roots of host plants. Using Phelipanche ramosa as the model, experiments conducted in this study showed that seeds require a conditioning period of at least 4 d to be receptive to the synthetic germination stimulant GR24. A cDNA-AFLP procedure on seeds revealed 58 transcript-derived fragments (TDFs) whose expression pattern changed upon GR24 treatment. Among the isolated TDFs, two up-regulated sequences corresponded to an abscisic acid (ABA) catabolic gene, PrCYP707A1, encoding an ABA 8\u27-hydroxylase. Using the rapid amplification of cDNA ends method, two full-length cDNAs, PrCYP707A1 and PrCYP707A2, were isolated from seeds. Both genes were always expressed at low levels during conditioning during which an initial decline in ABA levels was recorded. GR24 application after conditioning triggered a strong up-regulation of PrCYP707A1 during the first 18h, followed by an 8-fold decrease in ABA levels detectable 3 d after treatment. In situ hybridization experiments on GR24-treated seeds revealed a specific PrCYP707A1 mRNA accumulation in the cells located between the embryo and the micropyle. Abz-E2A, a specific inhibitor of CYP707A enzymes, significantly impeded seed germination, proving to be a non-competitive antagonist of GR24 with reversible inhibitory activity. These results demonstrate that P. ramosa seed dormancy release relies on ABA catabolism mediated by the GR24-dependent activation of PrCYP707A1. In addition, in situ hybridization corroborates the putative location of cells receptive to the germination stimulants in seeds

    Risk factors for infections caused by carbapenem-resistant Enterobacterales: an international matched case-control-control study (EURECA)

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    Cases were patients with complicated urinary tract infection (cUTI), complicated intraabdominal (cIAI), pneumonia or bacteraemia from other sources (BSI-OS) due to CRE; control groups were patients with infection caused by carbapenem-susceptible Enterobacterales (CSE), and by non-infected patients, respectively. Matching criteria included type of infection for CSE group, ward and duration of hospital admission. Conditional logistic regression was used to identify risk factors. Findings Overall, 235 CRE case patients, 235 CSE controls and 705 non-infected controls were included. The CRE infections were cUTI (133, 56.7%), pneumonia (44, 18.7%), cIAI and BSI-OS (29, 12.3% each). Carbapenemase genes were found in 228 isolates: OXA-48/like, 112 (47.6%), KPC, 84 (35.7%), and metallo-beta-lactamases, 44 (18.7%); 13 produced two. The risk factors for CRE infection in both type of controls were (adjusted OR for CSE controls; 95% CI; p value) previous colonisation/infection by CRE (6.94; 2.74-15.53; <0.001), urinary catheter (1.78; 1.03-3.07; 0.038) and exposure to broad spectrum antibiotics, as categorical (2.20; 1.25-3.88; 0.006) and time-dependent (1.04 per day; 1.00-1.07; 0.014); chronic renal failure (2.81; 1.40-5.64; 0.004) and admission from home (0.44; 0.23-0.85; 0.014) were significant only for CSE controls. Subgroup analyses provided similar results. Interpretation The main risk factors for CRE infections in hospitals with high incidence included previous coloni-zation, urinary catheter and exposure to broad spectrum antibiotics

    Current concepts in clinical radiation oncology

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    Prise de risque, "dérives" et autres imprudences.

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    Examen de la spĂ©cificitĂ© et des diffĂ©rentes composantes de la prise de risque au travail : le danger, l'opĂ©rateur et les circonstances susceptibles de les mettre en prĂ©sence. La prise de risque s'exprime par des comportements trĂšs diffĂ©rents selon qu'il s'agit d'une situation oĂč le danger est manifeste, d'une situation incidentelle ou enfin d'une situation dans laquelle ne persistent que des risques peu critiques. Dans ce dernier cas, la notion de dĂ©rive est prĂ©sentĂ©e. Dans un deuxiĂšme temps sont examinĂ©es les diffĂ©rentes modalitĂ©s d'obtention d'un comportement conforme par les opĂ©rateurs. La rĂšgle, l'information, les actions propagandistes (concours de sĂ©curitĂ© notamment) et la gestion par les valeurs ou le contrĂŽle idĂ©ologique sont analysĂ©s en tant que processus d'influence. En conclusion, la prise de risque est envisagĂ©e comme le rĂ©sultat d'une confrontation entre les exigences techniques de la situation de travail et les diffĂ©rentes logiques de prudence recensĂ©es

    Evolution de l'accidentabilité au travail en France de 1974 à 1994 : quelques constats, des questions, quelles réponses ?

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    Le rappel de l'évolution des principaux résultats nationaux de sécurité (taux de fréquence, taux de gravité) de 1974 à 1994, permet de former un constat d'amélioration de l'accidentabilité au travail. Au-delà de ce constat, on distingue toutefois plusieurs motifs d'interrogation : évolution différenciée des groupements d'activité, dispersion des résultats, augmentation de la gravité, régression durant la période 1987-1990. De telles incertitudes sont l'occasion de souligner que la nécessité de conférer aux données statistiques une signification dépassant le seul constat, impose un changement de paradigme. Ce changement est illustré par les explications avancées au sujet de la régression évoquée (87-90). Le retour à l'amélioration permet également de rappeler l'existence de mécanismes de régulation internes à l'entreprise ou institutionnels tout en constatant que ni leur réactivité ni leur ampleur ne sont connues

    La fonction de prévention chez l'opérateur. Mise en évidence de conduites sécuritaires au cours d'une activité de chantier.

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    Cette Ă©tude de type clinique, a pour objet la gestion de la sĂ©curitĂ© par l'opĂ©rateur. A partir de l'analyse d'une activitĂ© de chantier (remplacement d'un coffret disjoncteur sur poteau) effectuĂ©e par une Ă©quipe de 2 ou 3 opĂ©rateurs, deux types de conduites sĂ©curitaires sont distinguĂ©es : les comportements prudents, conformes aux rĂšgles prescrites de sĂ©curitĂ© ; les pratiques informelles, ou "savoir-faire de prudence", qualifiĂ©es souvent de tours de mains, ficelles de mĂ©tier acquises par expĂ©rience professionnelle, "sur le tas". Les communications verbales Ă©changĂ©es au sein de l'Ă©quipe indiquent Ă©galement que celle-ci gĂšre non seulement la sĂ©curitĂ© immĂ©diate mais fait aussi spontanĂ©ment de la prĂ©vention Ă  plus long terme. L'ensemble des donnĂ©es analysĂ©es met en Ă©vidence la complexitĂ© de la prise en charge de la sĂ©curitĂ© par l'opĂ©rateur et souligne l'intĂ©rĂȘt qu'il y aurait Ă  amĂ©liorer la capacitĂ© d'anticipation pour une meilleure gestion des alĂ©as

    Anthropotechnological analysis of industrial accidents in Brazil.

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    The Brazilian Ministry of Labour has been attempting to modify the norms used to analyse industrial accidents in the country. For this purpose, in 1994 it tried to make compulsory use of the causal tree approach to accident analysis, an approach developed in France during the 1970s, without having previously determined whether it is suitable for use under the industrial safety conditions that prevail in most Brazilian firms. In addition, opposition from Brazilian employers has blocked the proposed changes to the norms. The present study employed anthropotechnology to analyse experimental application of the causal tree method to work-related accidents in industrial firms in the region of Botucatu, SĂŁo Paulo. Three work-related accidents were examined in three industrial firms representative of local, national and multinational companies. On the basis of the accidents analysed in this study, the rationale for the use of the causal tree method in Brazil can be summarized for each type of firm as follows: the method is redundant if there is a predominance of the type of risk whose elimination or neutralization requires adoption of conventional industrial safety measures (firm representative of local enterprises); the method is worth while if the company's specific technical risks have already largely been eliminated (firm representative of national enterprises); and the method is particularly appropriate if the firm has a good safety record and the causes of accidents are primarily related to industrial organization and management (multinational enterprise)
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