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Annemieke Schuurhof Riny Janssen Hanneke de Groot Hennie M Hodemaekers Arja de Klerk Jan LL Kimpen Louis Bont 《Respiratory research》2011,12(1):121
Background
Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis in infants. Following RSV bronchiolitis, 50% of children develop post-bronchiolitis wheeze (PBW). Animal studies have suggested that interleukin (IL)-10 plays a critical role in the pathogenesis of RSV bronchiolitis and subsequent airway hyperresponsiveness. Previously, we showed that ex vivo monocyte IL-10 production is a predictor of PBW. Additionally, heterozygosity of the single-nucleotide polymorphism (SNP) rs1800872 in the IL10 promoter region was associated with protection against RSV bronchiolitis.Methods
This study aimed to determine the in vivo role of IL-10 in RSV pathogenesis and recurrent wheeze in a new cohort of 235 infants hospitalized for RSV bronchiolitis. IL-10 levels in nasopharyngeal aspirates (NPAs) were measured at the time of hospitalization and the IL10 SNP rs1800872 genotype was determined. Follow-up data were available for 185 children (79%).Results
Local IL-10 levels during RSV infection turned out to be higher in infants that later developed physician diagnosed PBW as compared to infants without PBW in the first year after RSV infection (958 vs 692 pg/ml, p = 0.02). The IL10 promoter SNP rs1800872 was not associated with IL-10 concentration in NPAs.Conclusion
The relationship between high local IL-10 levels during the initial RSV infection and physician diagnosed PBW provides further evidence of the importance of the IL-10 response during RSV bronchiolitis. 相似文献113.
Sottofattori E Anzaldi M Mazzei M Miele M Balbi A Pyshnyi DS Zakharova OD Abramova TV 《Bioorganic & medicinal chemistry》2005,13(5):1515-1522
New compounds having tri- or pentamethylenamine linker functions were synthesized. These derivatives were covalently attached through the 5'-phosphoramide linkage to heptanucleotide pd(CCAAACA). Complementary complexes of the octanucleotide pd(TGTTTGGC) and above oligonucleotide conjugates were tested for their thermodynamic response. The T(m) data and thermodynamic parameters for complex formation confirmed the ability of chromone (gamma-pyrone) derivatives to stabilize strongly the 7-mer/8-mer complementary complex. Moreover, benzochromone (naphthopyrane) and, surprisingly, tetrahydropyrimidinethanone derivatives showed the capacity of stabilizing this 7-mer/8-mer complementary complex. The effect of all these compounds on the stability of the oligonucleotide complexes (DeltaDeltaG at 37 degrees C ranged from -1.2 to -2.0 kcal/mol) was shown to be comparable to the effect of one nucleotide base pair and similar to the effect (DeltaDeltaG at 37 degrees C ranged from -1.5 to -2.0 kcal/mol) found for acridine-oligonucleotide conjugates, which served as a reference in this study. 相似文献
114.
Phylogenetic relationships of the tribe Operophterini (Lepidoptera, Geometridae): a case study of the evolution of female flightlessness 总被引:1,自引:0,他引:1
NIINA SNÄLL TOOMAS TAMMARU NIKLAS WAHLBERG JAAN VIIDALEPP KAI RUOHOMÄKI MARJA-LIISA SAVONTAUS KIRSI HUOPONEN 《Biological journal of the Linnean Society. Linnean Society of London》2007,92(2):241-252
A molecular phylogenetic analysis was conducted in order to reconstruct the evolution of female flightlessness in the geometrid tribe Operophterini (Lepidoptera, Geometridae, Larentiinae). DNA variation in four nuclear gene regions, segments D1 and D2 of 28S rRNA, elongation factor 1α , and wingless , was examined from 22 species representing seven tribes of Larentiinae and six outgroup species. Direct optimization was used to infer a phylogenetic hypothesis from the combined sequence data set. The results obtained confirmed that Operophterini (including Malacodea ) is a monophyletic group, and Perizomini is its sister group. Within Operophterini, the genus Malacodea is the sister group to the genera Operophtera and Epirrita , which form a monophyletic group. This relationship is also supported by morphological data. The results suggest that female flightlessness has evolved independently twice: first in the lineage of Malacodea and, for the second time, in the lineage of Operophtera after its separation from the lineage of Epirrita . An alternative reconstruction (i.e. recovery of flight ability in an ancestor of Epirrita ) appears unlikely for various reasons. The similarities shared by Epirrita with a basal representative of Perizomini, Perizoma didymatum , allow the proposal of a sequence of evolutionary events that has led to flightlessness. It is likely that the transition to female flightlessness in the two lineages of Operophterini occurred after the colonization of stable forest habitats, followed by the evolution of a specific set of permissive traits, including larval polyphagy, limited importance of adult feeding, and adult flight during the cold months of the season. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 241–252. 相似文献
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Abstract The chemical compositions of a number of halophytes from salt marshes on Ynys Môn (Anglesey), Wales, and of some related mesophytes and sand dune plants have been determined. Analyses of the inorganic ions broadly confirmed the existence of a characteristic chemical composition of many monoco-tyledonous salt-marsh plants in that they contain high levels of potassium and relatively low levels of sodium. In contrast to most dicotyledonous halophytes, especially members of the Chenopodiacease, the monocots restrict the entry of inorganic ions and use high levels of soluble sugars to maintain an adequate solute potential. Low calcium levels were not found to be a feature of these plants, as was previously reported. The large amounts of sugars found in the monocotyle-donous plants suggested that they must be located mainly in the vacuoles, in contrast to glycinebetaine which is thought to accumulate principally in the cytoplasm of the salt accumulating Chenopodiaceae. The monocotyledonous halophytes which accumulate proline differ from the normal monocotyledonous physiotype in the accumulation of larger quantities of sodium. Triglochin maritima is one species of this type, and Puccinellia maritima a less extreme example. Spartina spp. accumulating glycinebetaine and β-dimethyl-sulphoniopropionate also have unusually high inorganic ion contents for monocots. Several salt marsh plants contained large quantities of amino acids other than proline. As with ionic composition, the nature of the organic solutes broadly followed taxonomic lines. The usefulness of the physiotype concept is discussed. 相似文献
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Prevention and treatment of respiratory syncytial virus bronchiolitis and postbronchiolitic wheezing
Jan LL Kimpen 《Respiratory research》2002,3(1):2
Growth factors mediate tissue interactions and regulate a variety of cellular functions that are critical for normal lung development and homeostasis. Besides their involvement in lung pattern formation, growth and cell differentiation during organogenesis, these factors have been also implicated in modulating injury-repair responses of the adult lung. Altered expression of growth factors, such as transforming growth factor β1, vascular endothelial growth factor and epidermal growth factor, and/or their receptors, has been found in a number of pathological lung conditions. In this paper, we discuss the dual role of these molecules in mediating beneficial feedback responses or responses that can further damage lung integrity; we shall also discuss the basis for their prospective use as therapeutic agents. 相似文献