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101.
Retinoid acid receptor-related Orphan Receptor Alpha (RORA) was recently identified as a susceptibility gene for asthma in a genome-wide association study. To investigate the impact of RORA on asthma susceptibility, we performed a genetic association study between RORA single nucleotide polymorphisms (SNPs) in the vicinity of the asthma-associated SNP (rs11071559) and asthma-related traits. Because the regulatory region of a previously implicated asthma susceptibility gene, Neuropeptide S receptor 1 (NPSR1), has predicted elements for RORA binding, we hypothesized that RORA may interact biologically and genetically with NPSR1. 37 RORA SNPs and eight NPSR1 SNPs were genotyped in the Swedish birth cohort BAMSE (2033 children) and the European cross-sectional PARSIFAL study (1120 children). Seven RORA SNPs confined into a 49 kb region were significantly associated with physician-diagnosed childhood asthma. The most significant association with rs7164773 (T/C) was driven by the CC genotype in asthma cases (OR = 2.0, 95%CI 1.36–2.93, p = 0.0003 in BAMSE; and 1.61, 1.18–2.19, p = 0.002 in the combined BAMSE-PARSIFAL datasets, respectively), and strikingly, the risk effect was dependent on the Gln344Arg mutation in NPSR1. In cell models, stimulation of NPSR1 activated a pathway including RORA and other circadian clock genes. Over-expression of RORA decreased NPSR1 promoter activity further suggesting a regulatory loop between these genes. In addition, Rora mRNA expression was lower in the lung tissue of Npsr1 deficient mice compared to wildtype littermates during the early hours of the light period. We conclude that RORA SNPs are associated with childhood asthma and show epistasis with NPSR1, and the interaction between RORA and NPSR1 may be of biological relevance. Combinations of common susceptibility alleles and less common functional polymorphisms may modify the joint risk effects on asthma susceptibility.  相似文献   
102.

Aim

Toll-like receptors (TLR) play a crucial role in innate immunity, protecting the host from pathogens such as viruses. Genetic variations in TLRs have been associated with the severity of viral bronchiolitis in infancy and with the later occurrence of post-bronchiolitis asthma. The aim of the present study was to evaluate if there are any exploratory associations between TLR gene polymorphisms and lung function at 5 to 7 years of age in former bronchiolitis patients.

Methods

We performed impulse oscillometry (IOS) at the median age of 6.3 years for 103 children who had been hospitalized for bronchiolitis at less than six months of age. The main parameters evaluated were airway resistance and reactance at 5Hz in baseline and post-exercise measurements. Data on single nucleotide polymorphisms (SNP) of TLR1 rs5743618, TLR2 rs5743708, TLR6 rs5743810 and TLR10 rs4129009 (TLR2 subfamily) and TLR3 rs3775291, TLR4 rs4986790, TLR7 rs179008, TLR8 rs2407992 and TLR 9 rs187084 were available for analyses.

Results

The TLR4 rs4986790 wild genotype A/A was associated with a greater Rrs5 response (0.72 vs. -0.42, p = 0.03) to exercise. In TLR6 rs5743810, the minor allele T was associated with greater Rrs5 response (0.80 vs. -0.03, p = 0.04) to exercise. In TLR7 rs179008, the major allele A was associated with baseline decline in dRrs/df (-1.03 vs 0.61, p = 0.01) and increased Fres (2.28 vs. 0.89, p = 0.01) in girls.

Conclusion

Among the nine studied TLRs, only TLR7 rs179008 showed some exploratory associations with post-bronchiolitis lung function deficiency, and polymorphisms of TLR4 rs4986790, and TLR6 rs5743810 in particular, with airway reactivity. These findings call for further confirmatory studies.  相似文献   
103.

Objective

To determine whether there are differences in age and sex distribution and presence of comorbidities between participants included in randomized controlled trials of acetylcholinesterase inhibitors and nationwide cohort of persons with Alzheimer’s disease.

Methods

PubMed, Scopus and Cochrane Library databases were searched for original articles from their inception to January 4, 2015. Double-blind randomized controlled trials with donepezil, rivastigmine or galantamine compared to placebo in participants with Alzheimer’s disease were included. Data from a nationwide cohort of persons with clinically verified diagnoses of Alzheimer’s disease was defined as a reference population.

Results

128 full-text articles were assessed for eligibility, 31 of them fulfilled criteria. Mean age of participants in randomized controlled trials (n = 15,032) was 5.8 years lower (95% CI 5.7 to 5.9, P < 0.001), compared to the mean age of 79.7 years in the reference population with Alzheimer’s disease (n = 28,093). Most of the articles did not report age distribution of participants. The proportion of women was 63.2% (9,475/14,991) in randomized controlled trials and 67.8% (19,043/28,093) (P < 0.001) in the reference population. Information on comorbidities and use of concomitant drugs were lacking or poorly reported in most articles.

Conclusions

There is a discrepancy between participants in randomized controlled trials of acetylcholinesterase inhibitors and real-life population with Alzheimer’s disease. Participants in randomized controlled trials were significantly younger. Further, more detailed reporting of age distribution, comorbidities and concomitant drugs would be important information for clinicians when evaluating conclusions from randomized controlled trials to real-life practice. The existing recommendations of inclusion of older people should be followed to ensure safe pharmacotherapy for older people.  相似文献   
104.
Eleven monoclonal antibodies, directed versus the T8 glycoprotein, were compared using enzyme digestion, phylogenetic comparisons, cross-blocking of antibody binding, and blocking of specific cell-mediated lympholysis (CML). It was found that none of the 11 anti-T8 antibodies tested define the same epitope on the T8 glycoprotein. Some of these antibodies react, however, with closely related structures, as shown by cross-blocking of antibody binding and similar enzyme sensitivity of the epitopes. Moreover, these structural related epitopes show a similar involvement in the effector phase of CML reactions, since the antibodies to these neighboring epitopes inhibit the same CML reactions. Thus, it is possible to apply structural and functional criteria to define "regions" on the T8 glycoprotein, some of which are consistently involved in CML reactions, some never, and some of these regions appear to be involved in specific effector-target cell combinations only.  相似文献   
105.
Cyclosporin was previously shown to interfere with--but not to abolish--the increased activities of lysosomes and mitochondria consequent to a mitogenic activation of normal mouse lymphocytes. This was evident from the fluorescence profiles of cell populations after vital staining with euchrysine (giving a lysosomal-specific red fluorescence) and rhodamine-123 (giving a mitochondrial-specific green fluorescence). Fluorescence profiles of the population of cells not exposed to a mitogen were also altered by cyclosporin, with lower lysosomal and mitochondrial fluorescence of these cell populations. In order to find out more precisely what could be the direct effects of cyclosporin on those cellular organelles, our cyclosporin-sensitive (BE7) and cyclosporin-resistant (LB7) lymphoblastoid cell lines were tested and showed clear-cut differences. Only minor effects could be detected for the lysosomal and mitochondrial activities of the resistant cells. On the contrary, cyclosporin caused, in the cells of the sensitive clone BE7, a clear decrease of mitochondrial activity together with an unexpected increase of the red fluorescence of euchrysine. The latter might not correspond to a real increase of the lysosomal activity of such cells. Indeed electron microscopy studies do not show higher numbers of lysosomes; rather they show that numerous vacuoles appear in the cytoplasm of the cyclosporin-treated BE7 cells (but not in the cells of the resistant clone and not in untreated cells of either types).  相似文献   
106.
Seppo Koponen 《Ecography》1987,10(4):278-285
Ground-living spiders were studied, using pitfall traps, in six habitats between 580 and 960 m (deciduous forest, fir forest, forest-line and three alpine mountain top sites) on Mont du Lac des Cygnes. Altogether 88 species of spiders were found during the study summer (June-mid-September 1985), of which 51 belonged to Linyphiidae (s. lat.), 9 to Lycosidae and 8 to Gnaphosidae. The highest species number and diversity were found in the forest-line habitat, the highest individual number on the main summit and the lowest in deciduous forest, the lowest site. Lycosidae and Gnaphosidae species and individuals characterized the alpine habitats. Linyphiidae (especially Linyphiinae) the forested sites and Amaurobiidae and Agelenidae the deciduous forest site. Erigoninae occurred commonly at all sites; their individual numbers were very high at coniferous forest sites. The dominant species in all three alpine habitats was Pardosa concinna , on the forest-line Hybocoptus gibbosus , in balsam fir forest Sisicottus montanus and in deciduous forest Amaurobius borealis . The material included several (sub)arctic-alpine species.  相似文献   
107.
Three groups of one summer old rainbow trout were exposed for 22 days either to normoxia (100%) or moderate oxygen supersaturation; 120% and 140%. After the exposure, all groups were transported for three hours in hyperoxic conditions (123% O2) thus simultaneously experiencing density and handling stress. The recovery of rainbow trout to multiple stressors was measured in normoxic conditions. Moderate oxygen supersaturation did not have any negative effects on growth, feed conversion and blood hematology measured over 22 days. On the other hand, the combined effects of the stressful environment in the fish farm and oxygen supersaturation resulted in a 3-fold increase in plasma cortisol levels in those with 100% and 120% O2 supersaturation and a 2-fold increase in the 140% supersaturation group. Furthermore, the stress response after transportation was lowest in the 140% group 24 hours after recovery but highest after 70 hours. Moderate hyperoxia or transportation stress did not change glutathione concentrations in liver indicating that routine sampling does not affect hepatic glutathione status. Our results indicate that moderate O2 supersaturation (<140%) could be considered as feasible in cultivation of rainbow trout since no harmful effects were found.  相似文献   
108.
A public concern is continuously arising about the presence of natural and anthropogenic compounds which affect human health by modulating normal endocrine functions. These substances, defined as endocrine disrupting compounds (EDC) represent an heterogeneous class of molecules either steroidal or not, sharing the ability of interfering with the endocrine system via nuclear receptor signaling pathways. Therefore there is an urgent need for high throughput screening systems able to detect EDCs and evaluate their biological activity. However, little attention has been dedicated to the development of assays for androgen-like compounds. The present work describes the development and optimization of a new rapid and sensitive bioluminescent yeast-based bioassay for androgen-like compounds in a 96-well microplate format. The bioassay is based on recombinant Saccharomyces cerevisiae cells modified to express human androgen receptor (hAR) and containing the sequence androgen response element (ARE) which drives the expression of Photinus pyralis luciferase, used as reporter gene. A recombinant yeast strain constitutively expressing luciferase was used as external control to correct the light signal accordingly to cell viability and sample matrix aspecific effects. The bioassay responds to testosterone as reference androgen in a concentration-dependent manner from 0.05 to 1000 nM allowing an accurate and precise quantitative evaluation in aqueous environmental samples down to 10(-11)mol/L. Other known androgen-like compounds exhibit similar dose-response behavior, thus permitting the use of the bioassay for an overall detection of androgen-like effect in environmental samples.  相似文献   
109.
A novel approach to localize and reconstruct conformational IgE-binding epitope regions of hevein (Hev b6.02), a major natural rubber latex allergen, is described. An antimicrobial protein (AMP) from the amaranth Amaranthus caudatus was used as an immunologically non-IgE-binding adaptor molecule to which terminal or central parts of hevein were fused. Hevein and AMP share a structurally identical core region but have different N-terminal and C-terminal regions. Only 1 of 16 hevein-allergic patients showed weak IgE binding to purified native or recombinant AMP. Chimeric AMP with the hevein N terminus was recognized by IgE from 14 (88%) patients, and chimeric AMP with the hevein C terminus was recognized by IgE from 6 (38%) patients. In contrast, chimeric AMP containing the hevein core region was recognized by IgE from only two patients. When both the N-terminal and C-terminal regions of hevein were fused with the AMP core, IgE from all 16 patients bound to the chimera. This chimera was also able to significantly inhibit (>70%) IgE binding to the native hevein. On the contrary, linear synthetic peptides corresponding to hevein regions in the AMP chimeras showed no significant IgE binding capacity in either enzyme-linked immunosorbent assay or inhibition enzyme-linked immunosorbent assay. These results suggest that the IgE binding ability of hevein is essentially determined by its N-terminal and C-terminal regions and that major IgE-binding epitopes of hevein are conformational. The chimera-based epitope mapping strategy described here provides a valuable tool for defining structural epitopes and creating specific reagents for allergen immunotherapy.  相似文献   
110.
The Saami are regarded as extreme genetic outliers among European populations. In this study, a high-resolution phylogenetic analysis of Saami genetic heritage was undertaken in a comprehensive context, through use of maternally inherited mitochondrial DNA (mtDNA) and paternally inherited Y-chromosomal variation. DNA variants present in the Saami were compared with those found in Europe and Siberia, through use of both new and previously published data from 445 Saami and 17,096 western Eurasian and Siberian mtDNA samples, as well as 127 Saami and 2,840 western Eurasian and Siberian Y-chromosome samples. It was shown that the “Saami motif” variant of mtDNA haplogroup U5b is present in a large area outside Scandinavia. A detailed phylogeographic analysis of one of the predominant Saami mtDNA haplogroups, U5b1b, which also includes the lineages of the “Saami motif,” was undertaken in 31 populations. The results indicate that the origin of U5b1b, as for the other predominant Saami haplogroup, V, is most likely in western, rather than eastern, Europe. Furthermore, an additional haplogroup (H1) spread among the Saami was virtually absent in 781 Samoyed and Ob-Ugric Siberians but was present in western and central European populations. The Y-chromosomal variety in the Saami is also consistent with their European ancestry. It suggests that the large genetic separation of the Saami from other Europeans is best explained by assuming that the Saami are descendants of a narrow, distinctive subset of Europeans. In particular, no evidence of a significant directional gene flow from extant aboriginal Siberian populations into the haploid gene pools of the Saami was found.  相似文献   
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