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91.
Background
Airway remodelling is a feature of asthma including fragmentation of elastic fibres observed in the superficial elastin network of the airway wall. Fibered confocal fluorescence microscopy (FCFM) is a new and non-invasive imaging technique performed during bronchoscopy that may visualize elastic fibres, as shown by in vitro spectral analysis of elastin powder. We hypothesized that FCFM images capture in vivo elastic fibre patterns within the airway wall and that such patterns correspond with airway histology. We aimed to establish the concordance between the bronchial elastic fibre pattern in histology and FCFM. Second, we examined whether elastic fibre patterns in histology and FCFM were different between asthmatic subjects and healthy controls. Finally, the association between these patterns and lung function parameters was investigated.Methods
In a cross-sectional study comprising 16 subjects (8 atopic asthmatic patients with controlled disease and 8 healthy controls) spirometry and bronchoscopy were performed, with recording of FCFM images followed by endobronchial biopsy at the airway main carina. Elastic fibre patterns in histological sections and FCFM images were scored semi-quantitatively. Agreement between histology and FCFM was analysed using linearly weighted kappa κw.Results
The patterns observed in histological sections and FCFM images could be divided into 3 distinct groups. There was good agreement between elastic fibre patterns in histology and FCFM patterns (κw 0.744). The semi-quantitative pattern scores were not different between asthmatic patients and controls. Notably, there was a significant difference in post-bronchodilator FEV1 %predicted between the different patterns by histology (p = 0.001) and FCFM (p = 0.048), regardless of asthma or atopy.Conclusion
FCFM captures the elastic fibre pattern within the airway wall in humans in vivo. The association between post-bronchodilator FEV1 %predicted and both histological and FCFM elastic fibre patterns points towards a structure-function relationship between extracellular matrix in the airway wall and lung function.Trial registration
Netherlands Trial Register NTR1306 相似文献92.
93.
Rhinogobius candidianus is a freshwater goby distributed in north, northwest, west, and south Taiwan, but this species has been introduced to east Taiwan and became dominant. To investigate its native population genetic diversity and structure and evaluate the sources and diversity of translocated populations, the mitochondrial DNA control region and cytochrome b gene (1981 bp) from 220 specimens were analyzed. These results indicated that (1) the east populations originated from two sources in west Taiwan; (2) translocated populations exist in east Taiwan and south Taiwan; (3) many populations have likely been moved secondarily by human intervention; (4) the effective size of the populations had declined greatly; (5) within the native populations, the ancestral populations colonized Taiwan during the land bridge phase in the Pleistocene through north Taiwan; (6) the landform changes in Taiwan shaped the population structure; and (7) the landforms of the coastline during glaciation also shaped the native range. The low‐level genetic diversity, high population differentiation, and population decline greatly suggest the need for resource management and conservation interventions. Four clades (α–δ) should be managed as four distinct evolutionarily significant units, while the translocated populations should be managed as separate management units. Moreover, the translocated populations in east Taiwan should be evaluated and monitored carefully. 相似文献
94.
Effects of lipopolysaccharide on the expression of plasma membrane monoamine transporter (PMAT) at the blood–brain barrier and its implications to the transport of neurotoxins 下载免费PDF全文
Kuo‐Chen Wu Ya‐Hsuan Lu Yi‐Hsuan Peng Lih‐Ching Hsu Chun‐Jung Lin 《Journal of neurochemistry》2015,135(6):1178-1188
95.
Carvedilol is a third-generation β-blocker, with the S-enantiomer being more active than the R-enantiomer. Clinically, it has been used in the treatment of hypertension, congestive heart failure and angina pectoris. Each enantiomer of Carvedilol exhibits differential pharmacological effects. However, the cellular effects of individual enantiomer are not well understood. To gain insights into how each enantiomer affects cells, we analysed differential protein expression levels in vascular smooth muscle cells (A7r5) incubated separately with S- and R-Carvedilol by iTRAQ-coupled 2-D LC–MS/MS approach. Thirteen proteins were identified with statistically significant changes in cells incubated with S-Carvedilol, while the changes of most proteins incubated with R-Carvedilol were less significant. Among these proteins, actin in aortic smooth muscle (ACTA2), calmodulin, S100-A6, S100-A10, S100-A11, thioredoxin, lactadherin and heat-shock protein 105 kDa were found to be closely relevant with the clinical effects of Carvedilol. Furthermore, the changes in protein levels were validated by Western blot. Our findings thus provided molecular evidence on a comprehensive protein profile on Carvedilol–cell interaction, which may shed new light in molecular events underlying Carvedilol treatment. 相似文献
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97.
Derivative of plant phenolic compound inhibits the type III secretion system of Dickeya dadantii via HrpX/HrpY two‐component signal transduction and Rsm systems 下载免费PDF全文
98.
Murat Acemoglu Ernst Küsters Jürgen Baumann Ivan Hernandez Ching Pong Mak 《Chirality》1998,10(4):294-306
Various cellulose-2,3-bis-arylcarbamate-6-O-arylesters and cellulose-2,3-bis-arylester-6-O-arylcarbamates, designed to test the possible combined effects of the known tris-arylcarbamate and tris-arylester classes, were synthesized with high regioselectivity at O-C(6), and their use as CSP s in liquid chromatography for enantiomeric separations was investigated. The separations obtained with the synthesized CSP s were compared to the separations achieved on a self-packed reference column, consisting of cellulose-tris-(3,5-dimethylphenyl-carbamate) as CSP standard. Among the synthesized, regioselectively substituted cellulose derivatives, 2,3-bis-O-(3,5-dimethylphenylcarbamate)-6-O-benzoate-cellulose and 2,3-bis-O-(benzoate)-6-O-(3,5-dichlorophenylcarbamate)-cellulose gave the best CSP s for the separation of the test racemates. CSP s from regioselectively substituted cellulose derivatives seem to exhibit higher selectivities than cellulose-tris-(3,5-dimethylphenylcarbamate) for certain classes of racemic compounds. Chirality 10:294–306, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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100.
Front Cover: Exploring the expression bar code of SAA variants for gastric cancer detection 下载免费PDF全文