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Gallagher RM Kirkham JJ Mason JR Bird KA Williamson PR Nunn AJ Turner MA Smyth RL Pirmohamed M 《PloS one》2011,6(12):e28096
Aim
To develop and test a new adverse drug reaction (ADR) causality assessment tool (CAT).Methods
A comparison between seven assessors of a new CAT, formulated by an expert focus group, compared with the Naranjo CAT in 80 cases from a prospective observational study and 37 published ADR case reports (819 causality assessments in total).Main Outcome Measures
Utilisation of causality categories, measure of disagreements, inter-rater reliability (IRR).Results
The Liverpool ADR CAT, using 40 cases from an observational study, showed causality categories of 1 unlikely, 62 possible, 92 probable and 125 definite (1, 62, 92, 125) and ‘moderate’ IRR (kappa 0.48), compared to Naranjo (0, 100, 172, 8) with ‘moderate’ IRR (kappa 0.45). In a further 40 cases, the Liverpool tool (0, 66, 81, 133) showed ‘good’ IRR (kappa 0.6) while Naranjo (1, 90, 185, 4) remained ‘moderate’.Conclusion
The Liverpool tool assigns the full range of causality categories and shows good IRR. Further assessment by different investigators in different settings is needed to fully assess the utility of this tool. 相似文献13.
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Karen D. Bradham Brian D. Laird Pat E. Rasmussen Rosalind A. Schoof Sophia M. Serda Steven D. Siciliano 《人类与生态风险评估》2014,20(1):272-286
Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics and biological factors determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contamination may arise from multiple sources of toxic elements that may exist as different species that impact bioavailability. In turn, the bioaccessibility/bioavailability of soil and dust contaminants directly impacts human health risk. Research efforts focusing on development and application of in vitro and in vivo methods to measure the bioaccessibility/bioavailability of metal-contaminated soils have advanced in recent years. The objective of this workshop was to focus on developments in assessing the bioaccessibility/bioavailability of arsenic-contaminated soils, metals’ contamination in urban Canadian residences and potential children's exposures to toxic elements in house dust, an urban community-based study (i.e., West Oakland Residential Lead Assessment), bioavailability studies of soil cadmium, chromium, nickel, and mercury and human exposures to contaminated Brownfield soils. These presentations covered issues related to human health and bioavailability along with the most recent studies on community participation in assessing metals’ contamination, studies of exposures to residential contamination, and in vitro and in vivo methods development for assessing the bioaccessibility/bioavailability of metals in soils and dusts. 相似文献
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Pajon A Ionides J Diprose J Fillon J Fogh R Ashton AW Berman H Boucher W Cygler M Deleury E Esnouf R Janin J Kim R Krimm I Lawson CL Oeuillet E Poupon A Raymond S Stevens T van Tilbeurgh H Westbrook J Wood P Ulrich E Vranken W Xueli L Laue E Stuart DI Henrick K 《Proteins》2005,58(2):278-284
Data management has emerged as one of the central issues in the high-throughput processes of taking a protein target sequence through to a protein sample. To simplify this task, and following extensive consultation with the international structural genomics community, we describe here a model of the data related to protein production. The model is suitable for both large and small facilities for use in tracking samples, experiments, and results through the many procedures involved. The model is described in Unified Modeling Language (UML). In addition, we present relational database schemas derived from the UML. These relational schemas are already in use in a number of data management projects. 相似文献
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Moreland D. Gibbs Rosalind A. Reeves David Mandelman Qingli Mi Jun Lee Peter L. Bergquist 《Extremophiles : life under extreme conditions》2009,13(5):817-826
Thermus aquaticus DNA polymerase (Taq polymerase) made the polymerase chain reaction feasible and led to a paradigm shift in genomic analysis. Other Thermus polymerases were reported to have comparable performance in PCR and there was an analysis of their properties in the 1990s.
We re-evaluated our earlier phylogeny of Thermus species on the basis of 16S rDNA sequences and concluded that the genus could be divided into eight clades. We examined 22
representative isolates and isolated their DNA polymerase I genes. The eight most diverse polymerase genes were selected to
represent the eight clades and cloned into an expression vector coding for a His-tag. Six of the eight polymerases were expressed
so that there was sufficient protein for purification. The proteins were purified to homogeneity and examination of the biochemical
characteristics showed that although they were competent to perform PCR, none was as thermostable as commercially available
Taq polymerase; all had similar error-frequencies to Taq polymerase and all showed the expected 5′–3′ exonuclease activity. We conclude that the initial selection of T. aquaticus for DNA polymerase purification was a far-reaching and fortuitous choice but simple mutagenesis procedures on other Thermus-derived polymerases should provide comparable thermostability for the PCR reaction. 相似文献
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From simulations that begin with a random mix of two cell types, we monitor progress towards segregation driven by contact-mediated linkage of model cells, which is equivalent to the cell-cell adhesion of real cells. In comparison with real cell experiments, we show that this mechanical model can account for the observed extent of segregation obtained by differential adhesion in a 2D cell culture assay of cells with differentially expressed cadherin molecules. Calibration of virtual to real time allowed us to estimate a time course for these experiments that was within 50% agreement for the simulations compared to differential adhesion of cells. In contrast, simulations of differential adhesion do not account for the rate of segregation driven by interactions between EphB2 receptor and ephrinB1 expressing cells which occurs an order of magnitude faster. The latter result suggests that mechanisms additional or alternative to differential adhesion contribute to Eph-ephrin mediated cell segregation. 相似文献
20.
Yunfei Jiang Rachid Lahlali Chithra Karunakaran Thomas D. Warkentin Arthur R. Davis Rosalind A. Bueckert 《Plant, cell & environment》2019,42(1):354-372
Field pea (Pisum sativum), a major grain legume crop, is autogamous and adapted to temperate climates. The objectives of this study were to investigate effects of high temperature stress on stamen chemical composition, anther dehiscence, pollen viability, pollen interactions with pistil and ovules, and ovule growth and viability. Two cultivars (“CDC Golden” and “CDC Sage”) were exposed to 24/18°C (day/night) continually or to 35/18°C for 4 or 7 days. Heat stress altered stamen chemical composition, with lipid composition of “CDC Sage” being more stable compared with “CDC Golden.” Heat stress reduced pollen viability and the proportion of ovules that received a pollen tube. After 4 days at 35°C, pollen viability in flower buds decreased in “CDC Golden,” but not in “CDC Sage.” After 7 days, partial to full failure of anthers to dehisce resulted in subnormal pollen loads on stigmas. Although growth (ovule size) of fertilized ovules was stimulated by 35°C, heat stress tended to decrease ovule viability. Pollen appears susceptible to stress, but not many grains are needed for successful fertilization. Ovule fertilization and embryos are less susceptible to heat, but further research is warranted to link the exact degree of resilience to stress intensity. 相似文献