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101.
Objective
To evaluate whether responses to dynamic case-vignettes accurately reflect actual practices in complex emergency situations. We hypothesized that when obstetricians were faced with vignette of emergency situation identical to one they previously managed, they would report the management strategy they actually used. On the other hand, there is no reason to suppose that their response to a vignette based on a source case managed by another obstetrician would be the same as the actual management.Methods
A multicenter vignette-based study was used in 7 French maternity units. We chose the example of severe postpartum hemorrhage (PPH) to study the use of case-vignettes for assessing the management of complex situations. We developed dynamic case-vignettes describing incidents of PPH in several steps, using documentation in patient files. Vignettes described the postpartum course and included multiple-choice questions detailing proposed clinical care. Each participating obstetrician was asked to evaluate 4 case-vignettes: 2 directly derived from cases they previously managed and 2 derived from other obstetricians’ cases. We compared the final treatment decision in vignette responses to those documented in the source-case by the overall agreement and the Kappa coefficient, both for the cases the obstetricians previously managed and the cases of others.Results
Thirty obstetricians participated. Overall agreement between final treatment decisions in case-vignettes and documented care for cases obstetricians previously managed was 82% (Kappa coefficient: 0.75, 95% CI [0.62–0.88]). Overall agreement between final treatment decisions in case-vignettes and documented care in vignettes derived from other obstetricians’ cases was only 48% (Kappa coefficient: 0.30, 95% CI [0.12–0.48]). Final agreement with documented care was significantly better for cases based on their own previous cases than for others (p<0.001).Conclusions
Dynamic case-vignettes accurately reflect actual practices in complex emergency situations. Therefore, they can be used to assess the quality of management in these situations. 相似文献102.
Frédérique Thonon Rym Boulkedid Tristan Delory Sophie Rousseau Mahasti Saghatchian Wim van Harten Claire O’Neill Corinne Alberti 《PloS one》2015,10(4)
Background
There is an increasing need to evaluate the production and impact of medical research produced by institutions. Many indicators exist, yet we do not have enough information about their relevance. The objective of this systematic review was (1) to identify all the indicators that could be used to measure the output and outcome of medical research carried out in institutions and (2) enlist their methodology, use, positive and negative points.Methodology
We have searched 3 databases (Pubmed, Scopus, Web of Science) using the following keywords: [Research outcome* OR research output* OR bibliometric* OR scientometric* OR scientific production] AND [indicator* OR index* OR evaluation OR metrics]. We included articles presenting, discussing or evaluating indicators measuring the scientific production of an institution. The search was conducted by two independent authors using a standardised data extraction form. For each indicator we extracted its definition, calculation, its rationale and its positive and negative points. In order to reduce bias, data extraction and analysis was performed by two independent authors.Findings
We included 76 articles. A total of 57 indicators were identified. We have classified those indicators into 6 categories: 9 indicators of research activity, 24 indicators of scientific production and impact, 5 indicators of collaboration, 7 indicators of industrial production, 4 indicators of dissemination, 8 indicators of health service impact. The most widely discussed and described is the h-index with 31 articles discussing it.Discussion
The majority of indicators found are bibliometric indicators of scientific production and impact. Several indicators have been developed to improve the h-index. This indicator has also inspired the creation of two indicators to measure industrial production and collaboration. Several articles propose indicators measuring research impact without detailing a methodology for calculating them. Many bibliometric indicators identified have been created but have not been used or further discussed. 相似文献103.
Chandree?L. Beaulieu Jacek Majewski Jeremy Schwartzentruber Mark?E. Samuels Bridget?A. Fernandez Francois?P. Bernier Michael Brudno Bartha Knoppers Janet Marcadier David Dyment Shelin Adam Dennis?E. Bulman Steve?J.M. Jones Denise Avard Minh?Thu Nguyen Francois Rousseau Christian Marshall Richard?F. Wintle Yaoqing Shen Stephen?W. Scherer FORGE Canada Consortium Jan?M. Friedman Jacques?L. Michaud Kym?M. Boycott 《American journal of human genetics》2014,94(6):809-817
Inherited monogenic disease has an enormous impact on the well-being of children and their families. Over half of the children living with one of these conditions are without a molecular diagnosis because of the rarity of the disease, the marked clinical heterogeneity, and the reality that there are thousands of rare diseases for which causative mutations have yet to be identified. It is in this context that in 2010 a Canadian consortium was formed to rapidly identify mutations causing a wide spectrum of pediatric-onset rare diseases by using whole-exome sequencing. The FORGE (Finding of Rare Disease Genes) Canada Consortium brought together clinicians and scientists from 21 genetics centers and three science and technology innovation centers from across Canada. From nation-wide requests for proposals, 264 disorders were selected for study from the 371 submitted; disease-causing variants (including in 67 genes not previously associated with human disease; 41 of these have been genetically or functionally validated, and 26 are currently under study) were identified for 146 disorders over a 2-year period. Here, we present our experience with four strategies employed for gene discovery and discuss FORGE’s impact in a number of realms, from clinical diagnostics to the broadening of the phenotypic spectrum of many diseases to the biological insight gained into both disease states and normal human development. Lastly, on the basis of this experience, we discuss the way forward for rare-disease genetic discovery both in Canada and internationally. 相似文献
104.
105.
106.
Ferron M Boudiffa M Arsenault M Rached M Pata M Giroux S Elfassihi L Kisseleva M Majerus PW Rousseau F Vacher J 《Cell metabolism》2011,14(4):466-477
Osteoporosis is a multifactorial genetic disease characterized by reduction of bone mass due to dysregulation of osteoclast differentiation or maturation. Herein, we identified a regulator of osteoclastogenesis, the murine homolog of inositol polyphosphate 4-phosphatase type IIα (Inpp4bα). Expression of Inpp4bα is detected from early osteoclast differentiation to activation stage. Targeted expression of native Inpp4bα ex?vivo repressed whereas phosphatase-inactive Inpp4bα stimulated osteoclast differentiation. Inpp4bα acts on intracellular calcium level that modulates NFATc1 nuclear translocation and activation. In?vivo mice deficient in Inpp4b displayed increased osteoclast differentiation rate and potential resulting in decreased bone mass and osteoporosis. Importantly, INPP4B in human was identified as a susceptibility locus for osteoporosis. This study defined Inpp4b as a major modulator of the osteoclast differentiation and as a gene linked to variability of bone mineral density in mice and humans. 相似文献
107.
Kaustov L Ouyang H Amaya M Lemak A Nady N Duan S Wasney GA Li Z Vedadi M Schapira M Min J Arrowsmith CH 《The Journal of biological chemistry》2011,286(1):521-529
The eight mammalian Cbx proteins are chromodomain-containing proteins involved in regulation of heterochromatin, gene expression, and developmental programs. They are evolutionarily related to the Drosophila HP1 (dHP1) and Pc (dPc) proteins that are key components of chromatin-associated complexes capable of recognizing repressive marks such as trimethylated Lys-9 and Lys-27, respectively, on histone H3. However, the binding specificity and function of the human homologs, Cbx1-8, remain unclear. To this end we employed structural, biophysical, and mutagenic approaches to characterize the molecular determinants of sequence contextual methyllysine binding to human Cbx1-8 proteins. Although all three human HP1 homologs (Cbx1, -3, -5) replicate the structural and binding features of their dHP counterparts, the five Pc homologs (Cbx2, -4, -6, -7, -8) bind with lower affinity to H3K9me3 or H3K27me3 peptides and are unable to distinguish between these two marks. Additionally, peptide permutation arrays revealed a greater sequence tolerance within the Pc family and suggest alternative nonhistone sequences as potential binding targets for this class of chromodomains. Our structures explain the divergence of peptide binding selectivity in the Pc subfamily and highlight previously unrecognized features of the chromodomain that influence binding and specificity. 相似文献
108.
109.
110.
Hill C Soares P Mormina M Macaulay V Clarke D Blumbach PB Vizuete-Forster M Forster P Bulbeck D Oppenheimer S Richards M 《American journal of human genetics》2007,80(1):29-43
Island Southeast Asia (ISEA) was first colonized by modern humans at least 45,000 years ago, but the extent to which the modern inhabitants trace their ancestry to the first settlers is a matter of debate. It is widely held, in both archaeology and linguistics, that they are largely descended from a second wave of dispersal, proto-Austronesian-speaking agriculturalists who originated in China and spread to Taiwan approximately 5,500 years ago. From there, they are thought to have dispersed into ISEA approximately 4,000 years ago, assimilating the indigenous populations. Here, we demonstrate that mitochondrial DNA diversity in the region is extremely high and includes a large number of indigenous clades. Only a fraction of these date back to the time of first settlement, and the majority appear to mark dispersals in the late-Pleistocene or early-Holocene epoch most likely triggered by postglacial flooding. There are much closer genetic links to Taiwan than to the mainland, but most of these probably predated the mid-Holocene "Out of Taiwan" event as traditionally envisioned. Only approximately 20% at most of modern mitochondrial DNAs in ISEA could be linked to such an event, suggesting that, if an agriculturalist migration did take place, it was demographically minor, at least with regard to the involvement of women. 相似文献