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501.
Asthma has been systematically stigmatized in Hollywood feature films, including films seen by children. Through content analysis of 66 movies containing one or more scenes showing asthma, and through informant interviews with a dozen U.S. children about representative scenes, the study explores how stigmatizing portrayals are interpreted, accepted, or resisted. Children suffering from asthma actively counterargued with incriminating excerpts, but in some respects their healthy friends were less critical. Overall, children viewed stigmatizing scenes in terms of the social interaction and the social ethics entailed. They did not scrutinize the characters for damaged selfhood, per se, but dwelled on the social processes out of which stigma is erected.  相似文献   
502.
In allergic diseases such as asthma, eosinophils, basophils and mast cells, through release of preformed and newly generated mediators, granule proteins and cytokines, are recognized as key effector cells. While their surface protein phenotypes, mediator release profiles, ontogeny, cell trafficking and genomes have been generally explored and compared, there has yet to be any thorough analysis and comparison of their glycomes. Such studies are critical to understand the contribution of carbohydrates to the induction and regulation of allergic inflammatory responses and are now possible using improved technologies for detecting and characterizing cell-derived glycans. We thus report here the application of high-sensitivity mass spectrometric-based glycomics methodologies to the analysis of N-linked glycans derived from isolated populations of human mast cells, eosinophils and basophils. The samples were subjected to matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF) screening analyses and MALDI-TOF/TOF sequencing studies. Results reveal substantive quantities of terminal N-acetylglucosamine containing structures in both the eosinophil and the basophil samples, whereas mast cells display greater relative quantities of sialylated terminal epitopes. For the first time, we characterize the cell surface glycan structures of principal allergic effector cells, which by interaction with glycan-binding proteins (e.g. lectins) have the possibility to dictate cellular functions, and might thus have important implications for the pathogenesis of inflammatory and allergic diseases.  相似文献   
503.
α-Dystroglycan (DG) is a key component of the dystrophin-glycoprotein complex. Aberrant glycosylation of the protein has been linked to various forms of congenital muscular dystrophy. Unusually α-DG has previously been demonstrated to be modified with both O-N-acetylgalactosamine and O-mannose initiated glycans. In the present study, Fc-tagged recombinant mouse α-DG was expressed and purified from human embryonic kidney 293T cells. α-DG glycopeptides were characterized by glycoproteomic strategies using both nano-liquid chromatography matrix-assisted laser desorption ionization and electrospray tandem mass spectrometry. A total of 14 different peptide sequences and 38 glycopeptides were identified which displayed heterogeneous O-glycosylation. These data provide new insights into the complex domain-specific O-glycosylation of α-DG.  相似文献   
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506.

Background

The long-acting muscarinic antagonist (LAMA) umeclidinium (UMEC) and the combination of UMEC with the long-acting β2-agonist (LABA) vilanterol (UMEC/VI) are approved maintenance treatments for chronic obstructive pulmonary disease (COPD) in the US and EU. They are not indicated for the treatment of asthma.

Methods

In this 52-week, double-blind, placebo-controlled, parallel-group safety study (GSK study DB2113359; NCT01316887), patients were randomized 2:2:1 to UMEC/VI 125/25 mcg, UMEC 125 mcg, or placebo. Study endpoints included adverse events (AEs), clinical chemistry and hematology parameters, vital signs, 12-lead, and 24-hour Holter electrocardiograms. COPD exacerbations and rescue medication use were assessed as safety parameters; lung function was also evaluated.

Results

The incidence of on-treatment AEs, serious AEs (SAEs), and drug-related AEs was similar between treatment groups (AEs: 52–58%; SAEs: 6–7%; drug-related AEs: 12–13%). Headache was the most common AE in each treatment group (8–11%). AEs associated with the LAMA and LABA pharmacologic classes occurred at a low incidence across treatment groups. No clinically meaningful effects on vital signs or laboratory assessments were reported for active treatments versus placebo. The incidences of atrial arrhythmias with UMEC/VI 125/25 mcg were similar to placebo; for UMEC 125 mcg, the incidences of ectopic supraventricular beats, sustained supraventricular tachycardia, and ectopic supraventricular rhythm were ≥2% greater than placebo. With active treatments, COPD exacerbations were fewer (13–15% of patients reporting ≥1 exacerbation) and on average less rescue medication was required (1.6–2.2 puffs/day) versus placebo (24% reporting ≥1 exacerbation, 2.6 puffs/day). Both active treatments improved lung function versus placebo.

Conclusion

UMEC/VI 125/25 mcg and UMEC 125 mcg were well tolerated over 12 months in patients with COPD.  相似文献   
507.
Fish oil supplementation provides an inconsistent degree of protection from cardiovascular disease (CVD), which may be attributed to genetic variation. Single nucleotide polymorphisms (SNPs) in the elongation-of-very-long-chain-fatty-acids-2 (ELOVL2) gene have been strongly associated with plasma proportions of n-3 long-chain polyunsaturated fatty acids (LC-PUFA). We investigated the effect of genotype interaction with fish oil dosage on plasma n-3 LC-PUFA proportions in a parallel double-blind controlled trial, involving 367 subjects randomised to treatment with 0.45, 0.9 and 1.8 g/day eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (1.51:1) or olive oil placebo for 6 months. We genotyped 310 subjects for ELOVL2 gene SNPs rs3734398, rs2236212 and rs953413. At baseline, carriers of all minor alleles had lower proportions of plasma DHA than non-carriers (P = 0.021–0.030). Interaction between genotype and treatment was a significant determinant of plasma EPA (P < 0.0001) and DHA (P = 0.004–0.032). After the 1.8 g/day dose, carriers of ELOVL2 SNP minor alleles had approximately 30 % higher proportions of EPA (P = 0.002–0.004) and 9 % higher DHA (P = 0.013–0.017) than non-carriers. Minor allele carriers could therefore particularly benefit from a high intake of EPA and DHA in maintaining high levels of plasma n-3 PUFA conducive to protection from CVD.

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-013-0362-6) contains supplementary material, which is available to authorized users.  相似文献   
508.
Inconsistent effects of fish oil supplementation on plasma lipids may be influenced by genetic variation. We investigated 12 single nucleotide polymorphisms (SNPs) associated with dyslipidaemia in genome-wide association studies, in 310 participants randomised to treatment with placebo or 0.45, 0.9 and 1.8 g/day eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA) (1.51:1) in a 12-month parallel controlled trial. Effects of risk alleles were assessed as trait-specific genetic predisposition scores (GPS) and singly. GPS were positively associated with baseline concentrations of plasma total cholesterol, low-density-lipoprotein cholesterol and triglyceride (TG) and negatively with high-density-lipoprotein cholesterol. The TG-GPS was associated with 0.210 mmol/L higher TG per risk allele (P < 0.0001), but no effects of single TG SNPs were significant at baseline. After treatment with EPA and DHA, TG-GPS was associated with 0.023 mmol/L lower TG per risk allele (P = 0.72). No interactions between GPS and treatment were significant; however, FADS1 SNP rs174546 C/T interaction with treatment was a significant determinant of plasma TG concentration (P = 0.047, n = 267). Concentration differed between genotype groups after the 1.8 g/day dose (P = 0.026), decreasing by 3.5 (95 % CI −15.1 to 8.2) % in non-carriers of the risk T-allele (n = 30) and by 21.6 (95 % CI −32.1 to −11.2) % in carriers (n = 37), who showed a highly significant difference between treatments (P = 0.007). Carriers of the FADS1 rs174546 risk allele could benefit from a high intake of EPA and DHA in normalising plasma TG.

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-014-0412-8) contains supplementary material, which is available to authorized users.  相似文献   
509.
Changing temperature can substantially shift ecological communities by altering the strength and stability of trophic interactions. Because many ecological rates are constrained by temperature, new approaches are required to understand how simultaneous changes in multiple rates alter the relative performance of species and their trophic interactions. We develop an energetic approach to identify the relationship between biomass fluxes and standing biomass across trophic levels. Our approach links ecological rates and trophic dynamics to measure temperature‐dependent changes to the strength of trophic interactions and determine how these changes alter food web stability. It accomplishes this by using biomass as a common energetic currency and isolating three temperature‐dependent processes that are common to all consumer–resource interactions: biomass accumulation of the resource, resource consumption and consumer mortality. Using this framework, we clarify when and how temperature alters consumer to resource biomass ratios, equilibrium resilience, consumer variability, extinction risk and transient vs. equilibrium dynamics. Finally, we characterise key asymmetries in species responses to temperature that produce these distinct dynamic behaviours and identify when they are likely to emerge. Overall, our framework provides a mechanistic and more unified understanding of the temperature dependence of trophic dynamics in terms of ecological rates, biomass ratios and stability.  相似文献   
510.
The recognition of sialic acids by two strains of minute virus of mice (MVM), MVMp (prototype) and MVMi (immunosuppressive), is an essential requirement for successful infection. To understand the potential for recognition of different modifications of sialic acid by MVM, three types of capsids, virus-like particles, wild type empty (no DNA) capsids, and DNA packaged virions, were screened on a sialylated glycan microarray (SGM). Both viruses demonstrated a preference for binding to 9-O-methylated sialic acid derivatives, while MVMp showed additional binding to 9-O-acetylated and 9-O-lactoylated sialic acid derivatives, indicating recognition differences. The glycans recognized contained a type-2 Galβ1-4GlcNAc motif (Neu5Acα2-3Galβ1-4GlcNAc or 3′SIA-LN) and were biantennary complex-type N-glycans with the exception of one. To correlate the recognition of the 3′SIA-LN glycan motif as well as the biantennary structures to their natural expression in cell lines permissive for MVMp, MVMi, or both strains, the N- and O-glycans, and polar glycolipids present in three cell lines used for in vitro studies, A9 fibroblasts, EL4 T lymphocytes, and the SV40 transformed NB324K cells, were analyzed by MALDI-TOF/TOF mass spectrometry. The cells showed an abundance of the sialylated glycan motifs recognized by the viruses in the SGM and previous glycan microarrays supporting their role in cellular recognition by MVM. Significantly, the NB324K showed fucosylation at the non-reducing end of their biantennary glycans, suggesting that recognition of these cells is possibly mediated by the Lewis X motif as in 3′SIA-LeX identified in a previous glycan microarray screen.  相似文献   
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