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ABSTRACT Exon sequences upstream of splice sites play a critical role in mRNA processing, which is dependent on spliceosome interactions with these sites. Using antisense oligodeoxynucleotides (ODN), we targeted these and other sequences of the proinflammatory tumor necrosis factor-alpha (TNF-alpha) gene because it is multiply spliced and has been difficult to regulate with ODN in the past. ODN targeting exon sequences upstream of the donor splice sites of internal exons 2 (ORF4) and 3 (ORF6) significantly reduced TNF-alpha levels in stimulated U937 cells by 62%+/-7% and 51%+/-9%, respectively, in a dose-dependent manner but did not affect interleukin-6 (IL-6) levels. In contrast, ODN targeting the exon sequences downstream of the acceptor splice sites of exons 1, 2, and 3 failed to reduce TNF-alpha levels significantly under the same conditions. End-phosphorothioated ORF4 (ORF4-PE) significantly reduced TNF-alpha mRNA levels by greater than 80% (p < 0.001) and protein levels by 60% (p < 0.001) in U937 cells. ORF4-PE reduced newly synthesized TNF-alpha protein levels by >80% in lipopolysaccharide (LPS)-stimulated human macrophages, by greater than 60% in phorbol myristate acetate/phyto-hemagglutinin (PMA/PHA)-stimulated human peripheral blood mononuclear cells (PBMC), and by approximately 50% in LPS-stimulated murine monocytes. These results suggest that exon sequences flanking donor splice sites are highly susceptible target domains for antisense inhibition of TNF-alpha gene expression. 相似文献
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We have examined whether individual cells of the zona incerta of the thalamus have widespread projections across the brain. Double injections of different coloured fluorescent latex beads (red or green) were made, in various combinations, into regions of neocortex, dorsal thalamus or brainstem of Sprague-Dawley rats. These regions were chosen since they have been shown previously to receive projections from the zona incerta. We also made injections of different coloured beads into different regions of these same brain centres (ie, distinct cortical areas or individual dorsal thalamic and brainstem nuclei). In general, our results show that cells of the zona incerta have projections limited to one of these brain centres only. We saw very few double-labelled incertal cells after double injections of different coloured latex beads into either the neocortex/dorsal thalamus, neocortex/brainstem or dorsal thalamus/brainstem. Further, we show that within each of these brain centres, the projection patterns of individual incertal cells is rather restricted, since double injections of different coloured beads into separate regions of the same centre resulted in few double-labelled incertal cells. Taken together, these results suggest a very clear specificity of projection among cells of the zona incerta. Thus, although the cells of the zona incerta receive a plethora of inputs from many sources, it appears that its cells have a very clear and focussed output to distinct regions of the brain. 相似文献
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F J Molnar M Man-Son-Hing W B Dalziel S L Mitchell B E Power A M Byszewski P St John 《CMAJ》1999,161(4):393-395
BACKGROUND: Medical advice columns in newspapers can provide a valuable service by educating the general public about important health-related issues. However, these columns may be harmful if the advice or information given in them is incomplete, inappropriate or misleading. The objective of this study was to assess the safety and appropriateness of advice given to elderly readers of newspapers in medical advice columns. METHODS: Medical advice columns published in Canadian newspapers in 1995 were identified from a CD-ROM database. The articles that were selected were published in English and contained medical advice pertinent to elderly people about topics that could be found in a textbook of geriatric medicine. Fifty articles, randomly selected from the 109 articles that met these criteria, were independently assessed by 5 geriatricians. A scoring system was used to rate the ability to determine to which population the article applied, how well fact was distinguished from opinion, the degree to which critical issues were addressed, the safety and the appropriateness of the advice. When the kappa statistic for inter-rater agreement was 0.74 or less, a 2-stage Delphi process was used in an attempt to reach consensus. RESULTS: Agreement (kappa > 0.74) was eventually achieved for 232 (92.8%) of the 250 ratings. In 4 (8%) of the articles there was a high probability that the advice given could be applied to the wrong patient population; in 7 (14%) there was a high probability that opinion might be interpreted as fact; and in 11 (22%) the major critical issues were not identified. Of greatest concern, however, the advice in 25 (50%) of the articles was judged to be inappropriate, and in 14 (28%) advice may have been dangerous and potentially life-threatening. INTERPRETATION: Although medical advice columns have the potential to improve the health of elderly readers, a significant percentage of these articles contain inappropriate or even potentially dangerous advice. 相似文献
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One response to the global trend of increasing rates of student participation in tertiary education has been for universities to increase the number of intensive mode of delivery subjects available. This phenomenon extends to science subjects. Embarking on offering an undergraduate science subject in intensive mode for the first time at the Australian case example university, it was essential to first learn about good pedagogical design and practice from other educational organisations. To achieve this, a website audit of Australian universities was undertaken in tandem with a critical review of the Australian and international literature on intensive mode of delivery. While it was found that a majority of Australian universities offer science subjects in intensive mode, these subjects were primarily at the postgraduate level of study. The literature focusing on intensive mode in science was minimal. It revealed definitional ambiguity and conceptual non-uniformity as well as a range of positive, negative and inconclusive results in relation to the academic and ‘real-world’ outcomes of intensive mode. This review identifies a need for evidenced-based empirical research into the pedagogy around intensive mode for undergraduate science subjects. 相似文献
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Dieback of Passion Fruit in Surinam 总被引:1,自引:0,他引:1
In Surinam, the commercial cultivation of the yellow passion fruit (Passiflora edulis f. flavicarpa) is difficult due to the occurrence of dieback. Symptoms referred to as dieback include a decrease in elongation of the shoot end internodes after a period of normal growth leading to wilting and death of the shoots. Fruits from plants showing dieback symptoms are much smaller than those from healthy plants. From shoots with dieback symptoms, three fungi were isolated including Colletotrichum gloeosporioides. However, inoculation experiments with these fungi on shoots of vigorously growing plants were negative, even after wound inoculation. It appeared that plants with dieback symptoms had a poorly developed root system, From these roots Fusarium solani was isolated, which appeared to be highly pathogenic to roots of the yellow passion fruit. After inoculation of the roots of 3-month-old plants, roots became infected and the aerial plant parts showed typical dieback symptoms. Plants with their root system reduced either by inoculating with F. solani or by clipping, and subsequently inoculated with C. gloeosporioides on the aerial parts 2 weeks later, showed dieback symptoms and infection by C. gloeosporioides in shoots with these symptoms. Thus, a badly functioning root system, for example caused by infection of F. solani leads to dieback and predisposes plants to infection by C. gloeosporioides. The latter fungus itself is not a primary pathogen of shoots of the yellow passion fruit in Surinam. 相似文献
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Samuel Gee John Langton Dyce Duckworth Harrison Cripps T. Lauder Brunton W. Bruce Clarke Norman Moore Anthony Bowlby Samuel West C. B. Lockwood J. A. Ormerod D'Arcy Power W. P. Herringham H. J. Waring H. H. Tooth W. McAdam Eccles A. E. Garrod R. C. Bailey James Calvert W. H. H. Jessop F. H. Champneys T. Holmes Spicer W. S. A. Griffith A. E. Cumberbatch 《BMJ (Clinical research ed.)》1903,2(2242):1622-1623