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51.
Mohamed A. Elemraid Michelle Muller David A. Spencer Stephen P. Rushton Russell Gorton Matthew F. Thomas Katherine M. Eastham Fiona Hampton Andrew R. Gennery Julia E. Clark 《PloS one》2014,9(8)
Introduction
World Health Organization (WHO) radiological classification remains an important entry criterion in epidemiological studies of pneumonia in children. We report inter-observer variability in the interpretation of 169 chest radiographs in children suspected of having pneumonia.Methods
An 18-month prospective aetiological study of pneumonia was undertaken in Northern England. Chest radiographs were performed on eligible children aged ≤16 years with clinical features of pneumonia. The initial radiology report was compared with a subsequent assessment by a consultant cardiothoracic radiologist. Chest radiographic changes were categorised according to the WHO classification.Results
There was significant disagreement (22%) between the first and second reports (kappa = 0.70, P<0.001), notably in those aged <5 years (26%, kappa = 0.66, P<0.001). The most frequent sources of disagreement were the reporting of patchy and perihilar changes.Conclusion
This substantial inter-observer variability highlights the need for experts from different countries to create a consensus to review the radiological definition of pneumonia in children. 相似文献52.
Claire L. Cole Graham Rushton Gordon C. Jayson Egle Avizienyte 《The Journal of biological chemistry》2014,289(15):10488-10501
Heparan sulfate (HS) is a component of cell surface and extracellular matrix proteoglycans that regulates numerous signaling pathways by binding and activating multiple growth factors and chemokines. The amount and pattern of HS sulfation are key determinants for the assembly of the trimolecular, HS-growth factor-receptor, signaling complex. Here we demonstrate that HS 6-O-sulfotransferases 1 and 2 (HS6ST-1 and HS6ST-2), which perform sulfation at 6-O position in glucosamine in HS, impact ovarian cancer angiogenesis through the HS-dependent HB-EGF/EGFR axis that subsequently modulates the expression of multiple angiogenic cytokines. Down-regulation of HS6ST-1 or HS6ST-2 in human ovarian cancer cell lines results in 30–50% reduction in glucosamine 6-O-sulfate levels in HS, impairing HB-EGF-dependent EGFR signaling and diminishing FGF2, IL-6, and IL-8 mRNA and protein levels in cancer cells. These cancer cell-related changes reduce endothelial cell signaling and tubule formation in vitro. In vivo, the development of subcutaneous tumor nodules with reduced 6-O-sulfation is significantly delayed at the initial stages of tumor establishment with further reduction in angiogenesis occurring throughout tumor growth. Our results show that in addition to the critical role that 6-O-sulfate moieties play in angiogenic cytokine activation, HS 6-O-sulfation level, determined by the expression of HS6ST isoforms in ovarian cancer cells, is a major regulator of angiogenic program in ovarian cancer cells impacting HB-EGF signaling and subsequent expression of angiogenic cytokines by cancer cells. 相似文献
53.
The application of GIS-modelling to mustelid landscape ecology 总被引:1,自引:0,他引:1
54.
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56.
On association in a copula with time transformations 总被引:2,自引:0,他引:2
57.
We investigated how the interplay between environmental factors and presence of neighbouring populations determines the distribution and abundance of a small, endangered rodent, the water vole ( Arvicola terrestris ). We studied thriving and non-fragmented populations of water voles in the absence of their main predator, the introduced American mink ( Mustela vison ). A low degree of population fragmentation, such as the one characterizing the studied populations, was probably typical of water voles before their decline started. We found that under these conditions water voles' distribution is mainly determined by three environmental factors: presence of freshwater, adequate food, and cover. Variance in other factors is well tolerated by water voles. We obtained this result by the use of rule-based models in two separate areas. The two models correctly classified 81% and 83% of the observed cases, respectively. When optimised on one area and cross-validated on the other area the performance of the models was still high (73% and 79%) indicating that the models were robust and generalizable. We also found that the density of animals was lower in sub-optimal than in optimal habitat. We then tested the hypothesis that the number of neighbouring colonies determines the probability of finding voles in a given section. We found that the presence of nearby colonies was an important factor in determining the presence of water voles in sub-optimal habitat, while isolated patches of suitable habitat were less likely to host water voles. These observations suggest the possible presence of a source-sink dynamic, where an optimal habitat acts as a source for populating sub-optimal habitats that may be considered a sink habitat. These findings are discussed in the context of water vole conservation. 相似文献
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S. L. Schor A. M. Schor A. M. Grey J. Chen G. Rushton M. E. Grant I. Ellis 《In vitro cellular & developmental biology. Plant》1989,25(8):737-746
Summary We have previously demonstrated that confluent fetal fibroblasts migrate into three-dimensional collagen gels to a significantly
greater extent than their normal adult counterparts. Recent studies have revealed that this behavioral difference results
from the secretion by fetal fibroblasts of a soluble migration-stimulating factor (MSF) which acts on these cells in an autocrine
fashion. Adult fibroblasts do not produce MSF but remain responsive to it. Skin fibroblasts from cancer patients resemble
fetal fibroblasts (rather than normal adult cells) with respect to their migratory behavior on collagen gels and continued
production of MSF. This communication is concerned with elucidating the biochemical basis of MSF activity. Data are presented
indicating that a) hyaluronic acid is required for the elevated migratory activity displayed by confluent fetal and breast
cancer patient skin fibroblast; b) adult fibroblasts exhibit a bell-shaped dose-response to MSF, with maximal stimulation
of migration observed at a concentration of 10 ng/ml; c) the migratory activity of adult fibroblasts pre-incubated with MSF
remains high in the absence of additional factor: and d) MSF affects both the quantity and size class distribution of hyaluronic
acid synthesized by adult fibroblasts. We have previously speculated that the persistent fetal-like fibroblasts of breast
cancer patients play a direct role in disease pathogenesis by perturbing normal epithelial-mesenchymal interactions. The observations
reported here suggest that MSF-induced alterations in hyaluronic acid synthesis may contribute to the molecular basis of such
perturbations.
This work was funded by grants from the Cancer Research Campaign (CRC) and Medical Research Council (MRC), London, England. 相似文献