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1.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
2.
从芫花Daphne genkwa条的乙酸乙酯可溶部分分到3个结果性化合物,借助于波谱分析手段推断出Ⅱ为西瑞香素,Ⅲ为daphnodorin B。  相似文献   
3.
This article is a report of a meeting of dietitians held on 15 September 1992 in Birmingham to discuss the recommendations of a 'Medical Research Council Working Party on the Dietary Management of Phenylketonuria'. (Contributions on the day of the meeting came from Judith Houghton, Eleanor Weetch, Isabel Smith, Sheena Laing, Ruth Watling, John Walter, Rodney Pollitt.)  相似文献   
4.
应用聚合酶链反应(PCR)方法扩增苯丙氨酸羟化酶(PAH)基因的每个外显子及其侧翼的内含子,并克隆到M 13载体中进行序列分析。发现中国人苯丙酮尿症(Phenylketonuria,PKU)患者的PAH基因外显子3中有1个Arg~(111)→Ter~(111)的点突变,此突变与东方人最常见的突变单体型4呈连锁不平衡。此突变占中国人PAH等位基因的10%左右,但不存在于高加索人群中,表明在种族分化过程中PAH基因位点发生了互不相关的突变事件。  相似文献   
5.
Serum phenylalanine and tyrosine levels were measured in 26 patients with severe depression before and after receiving electroconvulsive therapy. The phenylalanine:tyrosine [P:T] ratio declined significantly for those responding to treatment but not for nonresponders. These findings are discussed in relation to tetrahydrobiopterin, the essential cofactor for the formation of noradrenaline, dopamine and serotonin and the hydroxylation of phenylalanine to tyrosine.  相似文献   
6.
A method for the simultaneous determination of the ratios of the three aromatic amino-acid residues in peptides was set up in acidic conditions. Binary and ternary mixtures of these amino acids were prepared, and first- and second-derivative spectra then calculated from their 0.1 nm resolution spectra between 240 and 320 nm. Certain spectral bands were chosen to differentiate tyrosine from tryptophan on the first-derivative spectra, and phenylalanine from tyrosine and tryptophan on the second-derivative spectra. Variation of the amplitude of the chosen bands was shown to be a linear function of the ratio of the aromatic amino acids in the mixture. This technique was validated with peptides whose sequence was known. The difference between theoretical and experimentally determined ratios was lower than 10%. Since the results are obtained as ratios, neither the concentration nor the nature of the peptide has to be known. The feasibility of application using a photodiode array detector with high resolution in reversed-phase high-performance liquid chromatography is discussed. © Munksgaard 1995.  相似文献   
7.
We previously reported that low levels of tyrosine (Tyr) and phenylalanine (Phe) alter the metastatic phenotype of B16-BL6 (BL6) murine melanoma and select for tumor cell populations with decreased lung colonizing ability. To more specifically characterize the effects of Tyr and Phe restriction on the malignant phenotype of BL6, we investigated in vitro attachment, invasion, proteinase expression, and chemotaxis of high and low metastatic BL6 variants. High metastatic variant cells were isolated from subcutaneous tumors of mice fed a nutritionally complete diet (ND cells) and low metastatic variant cells were isolated from mice fed a diet restricted in Tyr and Phe (LTP cells). Results indicate that attachment to reconstituted basement membrane (Matrigel) was significantly reduced in LTP cells as compared to ND cells. Attachment to collagen IV, laminin, and fibronectin were similar between the two variants. Invasion through Matrigel and growth factor-reduced Matrigel were significantly decreased in LTP cells as compared to ND cells. Zymography revealed the presence of M r 92 000 and M r 72 000 progelatinases, tissue plasminogen activator, and urokinase plasminogen activator in the conditioned medium of both variants; however, there were no differences in activity of these secreted proteinases between the two variants. Growth of the variants on growth factor-reduced Matrigel similarly induced expression of the M r 92 000 progelatinase. The variants exhibited similar chemotactic responses toward laminin. However, the chemotactic response toward fibronectin by LTP cells was significantly increased. MFR5, a monoclonal antibody which selectively blocks function of the 5 chain of the 5ß1 integrin, VLA-5, decreased the chemotactic response toward fibronectin of ND cells by 37%; the chemotactic response by LTP cells was reduced by 49%. This effect was specific for fibronectin-mediated chemotaxis since the chemotaxis toward laminin and invasion through Matrigel were not altered by the presence of MFR5. The surface expression of VLA-5 was significantly increased in LTP cells as compared to ND cells by flow cytometric analysis. These observations suggest that limitation of Tyr and Phe either directly modifies BL6 or selects for subpopulations with altered in vitro invasion, chemotaxis, and integrin expression.  相似文献   
8.
目的提高经典型苯丙酮尿症的产前诊断的成功率。方法在苯丙氨酸羟化酶(phenylalanine hydroxylase,PAH)基因附近选择了3个新的短串联重复序列(short tandem repeat,STR)位点(PAH26、PAH32和PAH9),进行扩增长度片段多态性分析,确定它们在中国人群的分布及在诊断中的应用价值。结果3个新的STR位点的多态信息含量分别为0.518(PAH26)、0.413(PAH32)和0.362(PAH9)。这3个位点之间,PAH9与第3内含子中的STR位点(TCTA)n之间存在连锁不平衡,其他位点组合不存在连锁不平衡。联合第3内含子中的STR位点(TCTA)n和2个新的位点,可以对家系中突变基因标记进行95%N断,并成功地用于4例产前诊断中。结论选择性地应用PAH基因中的3个STR位点组合,可以95%地区分经典型苯丙酮尿症家系中父母的两个基因,从而准确地进行快速产前诊断。  相似文献   
9.
内蒙古经典型苯丙酮尿症PAH基因外显子11突变的检测   总被引:2,自引:0,他引:2  
目的:研究内蒙古地区经典型苯丙酮尿症(PKU)苯丙氨酸羟化酶(PAH)基因突变的特点和频率,以提高该地区PKU的基因诊断率。方法:应用PCR—SSCP-银染法和DNA直接测序的方法,对22例内蒙古地区PKU病人PAH基因外显子11进行了检测。站果:检出一种已知突变Y356X(TAC→TAA),突变频率为13.6%。结论:内蒙古地区PKU病人PAH基因外显子11的突变频率均高于我国的其它北方人群,也高于云南PKU病人的突变频率,这为内蒙古地区PKU病人PAH基因分析和产前诊断提供了科学依据。  相似文献   
10.
Phenylketonuria (PKU, OMIM 261600) caused by phenylalanine hydroxylase (PAH) deficiency is an autosomal recessive disease that is characterized by abnormalities of phenylalanine metabolism. In this study, a total of 77 patients, originating from the central region of China and who were diagnosed with PAH deficiency at the third affiliated hospital of Zhengzhou University, were enrolled in this study. The 13 exons and 12 flanking introns of the PAH gene were analyzed by Sanger sequencing and next generation sequencing. The sequencing data were aligned to the hg19, PAHvdb and HGMD databases to characterize the genotypes of PKU patients, and genotype–phenotype correlations and BH4 responsiveness predictions were performed using BIOPKUdb. In total, 149 alleles were characterized among the 154 PKU alleles. These mutations were located in exons 2–13, and intron 12 of the PAH gene, with a relative frequency of ≥5%, for EX6-96A>G, p.R241C, p.R243Q, p.V399V and p.R53H. Additionally, a novel variant, p.D84G, was identified. The genotype correlated with clinical symptoms in 33.3–100% of the cases, depending on the disease severity, and BH4 responsiveness predictions show that only five patients with MHP-PKU and one patient with Mild-PKU were predicted to be BH4 responsive. In conclusion, we have characterized the mutational spectrum of PAH in the central region of China and have identified a novel mutation. The hotspot mutation information might be useful for screening, diagnosis and treatment of PKU.  相似文献   
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