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381.

Background

COPD patients have increased numbers of macrophages and neutrophils in the lungs. Interleukin-6 (IL-6) trans-signaling via its soluble receptor sIL-6R, governs the influx of innate immune cells to inflammatory foci through regulation of the chemokine CCL3. We hypothesized that there would be enhanced levels of IL-6, sIL-6R and CCL3 in COPD sputum.

Methods

59 COPD patients, 15 HNS and 15 S underwent sputum induction and processing with phosphate buffered saline to obtain supernatants for IL-6, sIL-6R and CCL3 analysis. Cytoslides were produced for differential cell counting and immunocytochemistry (COPD; n = 3) to determine cell type surface expression of the CCL3 receptors CCR5 and CCR1.

Results

COPD patients expressed higher levels (p < 0.05) of sIL-6R and CCL3 compared to controls (sIL-6R medians pg/ml: COPD 166.4 vs S 101.1 vs HNS 96.4; CCL3 medians pg/ml: COPD 117.9 vs S 0 vs HNS 2.7). COPD sIL-6R levels were significantly correlated with sputum neutrophil (r = 0.5, p < 0.0001) and macrophage (r = 0.3, p = 0.01) counts. Immunocytochemical analysis revealed that CCR5 and CCR1 were exclusively expressed on airway macrophages.

Conclusion

Enhanced airway generation of sIL-6R may promote IL-6 trans-signaling in COPD. Associated upregulation of CCL3 may facilitate the recruitment of macrophages into the airways by ligation of CCR1 and CCR5.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-014-0103-4) contains supplementary material, which is available to authorized users.  相似文献   
382.
Heavy metal contamination of water bodies has been a cause of grave concern around the globe. Analysis of various industrial effluents has revealed a perilous level of Cr (VI) and Ni (II). Pseudomonas aeruginosa is an extracellular polymeric substances (EPSs) producing bacterium. EPS has a great potential in the sequestration of heavy metal ions. In the present study efforts have been made to understand the effect of time, pH, and temperature on production of EPS by P. aeruginosa (MTCC 1688). The extracted EPS has been applied for removal of Ni (II) and Cr (VI) ions from aqueous system. The results revealed that highest EPS yield (26 mg/50 mL) can be obtained after 96 h of incubation at pH 6 and 32 °C temperature in 50 mL of culture. Treatment of 10 mg/L Cr (VI) and Ni (II) with 30 mg/L EPS resulted in the removal of 26% and 9% of Cr (VI) and Ni (II), respectively. Fourier-transform infrared spectral analysis revealed the involvement of –OH, –NH, C–O, diketone, and ester functional groups of EPS in the attachment of Cr (VI) ion while involvement of amide and –CO groups in Ni (II) binding with EPS. Scaling-up the production of EPS using bioreactor may further help in developing an efficient process for treatment of water polluted with Cr and Ni.  相似文献   
383.
Leishmania donovani, causative organism for visceral leishmaniasis, is responsible for considerable mortality and morbidity worldwide. Generation of drug-resistant variants continue to challenge the chemotherapy, the mainstay to fight the disease. The aim of current study was proteomic profiling of wild type (Ld-Wt) and arsenite-resistant (Ld-As20) L. donovani. Significant differences in protein profiles were observed between Ld-As20 and its parent Ld-Wt strain. Proteomic analysis of 158 spots from Ld-Wt and 144 spots from, Ld-As20 identified 77 and 74 protein entries, respectively, through MALDI-TOF/TOF based mass spectrometry and database search. A shift in the isoelectric point of few proteins was observed both in Ld-Wt and Ld-As20, which raises the possibility of continuous arsenite stress, resulting in the differences in the protein profiles of drug-resistant strain from its parent wild type strain. The comparative proteomic data holds the key for elucidation of the multifactorial and complex drug resistance mechanism, like arsenite resistance, in the parasite.  相似文献   
384.
Summary Effects of water content of the topsoil on the supply of manganese, zinc and copper to plants from an acid, siliceous sandy soil were investigated. The experiment was designed to provide a good supply of water and of nutrients other than those mentioned above at all times.Water content of the topsoil affected the root growth in that layer significantly. However, drying of the topsoil for as long as 42 days did not significantly affect the concentration of micronutrients in the shoots of oats, provided the plants did not experience water stress.Despite the acidic, siliceous sandy nature of the topsoil it showed a surprisingly high ability to render added manganese, zinc and copper unavailable. This phenomenon, probably mediated by organic matter, had a dominant effect on the exchangeable micronutrients in comparison to the effects due to fluctuations in soil water content.  相似文献   
385.
Summary A glasshouse experiment was conducted to study the effects of water content of the topsoil on the micronutrient nutrition of Italian ryegrass (Lolium multiflorum Lam.) growing in a siliceous sandy soil of marginal micronutrient status, with and without a supply of micronutrients at lower depths. The main objectives were to investigate whether micronutrient supplies would be sustained for the regrowth of defoliated grass after the topsoil had dried, and to assess the contribution made by small amounts of micronutrients in the subsoil to nutrient supply.In the absence of supply from deeper layers, topsoil drying rapidly induced deficiency of micronutrients, particularly of manganese, resulting in significant yield depression. When small amounts of micronutrients were present in a deeper, wet layer there was little reduction in yield after the topsoil had dried.The evidence suggests that, provided the roots had access to water in the subsoils, significant amounts of manganese, zinc and copper can be absorbed from topsoils as dry or drier than wilting point. Supply of micronutrients to the subsoil appears to have enhanced the efficiency of manganese absorption from dry topsoil.  相似文献   
386.
An efficient protocol for direct somatic embryogenesis in Capparis decidua has been developed. Mature zygotic embryos cultured in Murashige and Skoog (MS) liquid medium with 2,4-0 (0.1 mg l?1) and BA (0.5 mg l?1) produced somatic embryos directly without an intervening callus phase from the subepidermal cells. Treatment with ABA promoted maturation of somatic embryos and BA (1 mg l?1)promoted germination. One zygotic embryo produced approximately 230 somatic embryos within 14 to 15 weeks. Embryos germinated in eight weeks and acclimatized plants were transferred to pots.  相似文献   
387.
Expression of bovine pancreatic ribonuclease A in Escherichia coli   总被引:3,自引:0,他引:3  
A synthetic gene for bovine pancreatic ribonuclease A (RNase A) has been expressed in Escherichia coli as a fusion protein with beta-galactosidase linked by the tetrapeptide Ile-Glu-Gly-Arg. RNase A was cleaved from the fusion using factor Xa, and the resulting product purified and reconstituted. The isolated RNase A was chromatographically, catalytically, and immunologically identical with authentic RNase A. This work argues that the method suggested by Nagai and Thogersen [Nagai, K. & Thogersen, H. C. (1984) Nature (Lond.) 309, 810-812] for releasing fusion proteins is quite general, even when applied to particularly complicated expression problem. The procedure here makes RNase A available for the first time as a model for studying structure-function relationships in proteins using site-directed mutagenesis.  相似文献   
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