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871.
Mona-Rita Yacoub Matteo Trimarchi George Cremona Sara Dal Farra Giuseppe Alvise Ramirez Valentina Canti Emanuel Della Torre Mattia Baldini Patrizia Pignatti Mario Bussi Maria Grazia Sabbadini Angelo A Manfredi Giselda Colombo 《Clinical and molecular allergy : CMA》2015,13(1)
Background
The aetiopathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) is still unknown. The role of atopy and the concept of united airways in such patients are still a matter of debate. In this pilot study we aimed at evaluating the degree of eosinophilic inflammation and the frequency of atopy in a cohort of CRSwNP patients candidate for Functional Endoscopic Sinus Surgery (FESS) and assessing the association between these factors and relapsing forms of CRSwNP.Methods
30 patients (18 men, 12 women) with CRSwNP eligible for FESS were evaluated before and after surgery. Preoperative investigation included: history of previous relapse after FESS, clinical and laboratory allergologic assessment, spirometry, methacholine challenge, blood eosinophilia and determination of the fraction of nitric oxide in exhaled air (FeNO). Nasal fibroendoscopy, spirometry and FeNO determination were also assessed prospectively at 3 and 27 months post-FESS.Results
18/30 subjects were atopic, 6/18 (33 %) were monosensitized, 16/30 (53 %) were asthmatics and 10/30 (33 %) had non steroidalantinflammatory drugs (NSAIDs) hypersensitivity. Twenty-one patients (70 %) were classified as relapsers, 15/18 (83 %) among atopics, 6/12 (50 %) among non atopics (p = 0.05). Among patients with NSAIDs hypersensitivity, 9/10 (90 %) were relapsers. The median IgE concentration was 161.5 UI/mL in relapsers and 79 UI/mL in non-relapsers (ns). The mean FeNO decreased after FESS (43.1–26.6 ppb) in 84 % of patients, but this effect disappeared over time (FeNO = 37.7 ppb at 27 months). Higher levels of FeNO pre-FESS were detected in atopics, and in particular in relapsing ones (median 51.1 ppb vs 22.1, ns). Higher levels of FeNO pre-FESS were detected in asthmatic patients, especially in those who relapsed (median: 67 vs 64.85 ppb in non-relapsed patients, ns). The Tiffeneau Index (FEV1/FVC) was significantly lower in asthmatic relapsers than in non relapsers asthmatics (94.7 ± 11.1 versus 105 ± 5.9—p = 0.04). Patients with asthma and atopy had a major risk of relapse (p = 0.05).Conclusion
In our pilot study, atopy, severe asthma, bronchial inflammation, NSAIDs hypersensitivity and high level of total IgE are possible useful prognostic factors for the proneness to relapse after FESS. The role of allergy in CRSwNP pathogenesis should consequently be given deeper consideration. Allergen specific immunotherapy, combined with anti-IgE therapy, may have an immunomodulatory effect preventing polyps relapse and need to be investigated.Electronic supplementary material
The online version of this article (doi:10.1186/s12948-015-0026-8) contains supplementary material, which is available to authorized users. 相似文献872.
Glycosylation is one of the most abundant forms of protein posttranslational modification. O-glycosylation is a major type of protein glycosylation, comprising different types and structures expressed in several physiologic and pathologic conditions. The understanding of protein attachment site and glycan structure is of the utmost importance for the clarification of the role glycosylation plays in normal cells and in pathological conditions. Neoplastic transformation frequently shows the expression of immature truncated O-glycans. These aberrantly expressed O-glycans have been shown to induce oncogenic properties and can be detected in premalignant lesions, meaning that they are an important source of biomarkers. This article addresses the recent application of genetically engineered cancer cell models to produce simplified homogenous O-glycans allowing the characterization of cancer cells O-glycoproteomes, using advanced mass spectrometry methods and the identification of potential cancer-specific O-glycosylation sites. This article will also discuss possible applications of these biomarkers in the cancer field. 相似文献
873.
Eriston Vieira Gomes Lucas Breseguello
Do Nascimento Marcos Augusto
De Freitas Luiz Carlos Bhering Nasser Silvana Petrofeza 《Journal of Phytopathology》2011,159(2):94-99
Microsatellites are powerful markers to infer population genetic parameters. We used 10 microsatellite loci to characterize the genetic diversity and structure of 79 samples of Sclerotinia sclerotiorum isolated from four Brazilian dry bean populations and observed that eight of them were polymorphic within populations. We identified 102 different haplotypes ranging from 6 to 18 per locus. Analyses based on genetic diversity and fixation indices indicated variability among and within populations of 28.79% (FST = 28793) and 71.21%, respectively. To examine genetic relatedness among S. sclerotiorum isolates, we used internal spacer (ITS1‐5.8S‐ITS2) restriction fragment length polymorphism (PCR‐RFLP) and sequencing analysis. PCR‐RFLP analysis of these regions failed to show any genetic differences among isolates. However, we detected variability within the sequence, which does not support the hypothesis of clonal populations within each population. High variability within and among populations may indicate the introduction of new genotypes in the areas analysed, in addition to the occurrence of clonal and sexual reproduction in the populations of S. sclerotiorum in the Brazilian Cerrado. 相似文献
874.
Rodrigo Mendonça de Lucena Sávia Gavazza Lourdinha Florencio Mario T. Kato Marcos Antonio de MoraisJr 《World journal of microbiology & biotechnology》2011,27(12):2893-2902
The microorganisms diversity in a full-scale UASB reactor treating domestic sewage was studied by molecular techniques, with
the objective of identifying the population differences associated with the specific methanogenic activity (SMA) of the sludges.
Samples were collected at levels A (0.8 m; bottom), B (1.3 m), C (1.8 m), D (2.3 m) and E (2.8 m). Actinobacteria was dominant at the three lower points and should have been primarily responsible for the degradation of organic matter.
DNA sequences belonging to Methanomicrobiales order of Archaea domain was detected in all five levels with the majority producing methane from hydrogen and carbon dioxide. Points A and
E showed similar bacteria variety. The SMA of point A was the highest (0.374 g COD-CH4/g SSV.d); however, the point E showed much lower value, probably due to the predominance of Proteobacteria phylum, including sulfate-reducing bacteria. In the overall, the results obtained can be considered important because data
from full-scale UASB reactors treating domestic sewage remain scarce. 相似文献
875.
A wide variety of human diseases are associated with the formation of highly organized protein aggregates termed amyloid fibrils, whose growth (elongation) is due to the assembly of the basic molecular units (monomers) in a sequential polymerization process. Surface plasmon resonance (SPR) technology has been proposed as a powerful approach to study in detail the fibril elongation of some amyloidogenic peptides. In particular, the injection of monomers over immobilized fibrils allows to follow in real time, and on a very short time-scale, the kinetics of fibril growth. In the present study we confirmed and extended this application of SPR to Aβ(1-42), hampered till now by the very pronounced aggregation propensity of this peptide, involved in Alzheimer disease. We took advantage of a new synthetic strategy ("depsi-peptide" technique) which allows to obtain reliable seed-free solutions (monomers) as well as fibrils of Aβ(1-42). SPR data were consistent with a "dock-and-lock" mechanism underlying Aβ(1-42) elongation process. The setup of an assay monitoring the elongation kinetics is very useful for investigating potential anti-amyloidogenic compounds. Moreover, the possibility to reliably immobilize both Aβ(1-42) monomers and fibrils allows to measure the binding affinities of putative ligands for these different species. The approach applied here to Aβ(1-42) might well be also applied to the study of other fibrillogenic peptides/proteins or to the study of polymerization reactions in general. 相似文献
876.
Verónica Gomes Raquel Ribeiro Miguel A. Carretero 《Biodiversity and Conservation》2011,20(14):3577-3590
There is an increasing interest in understanding how species respond to the modifications of habitat attributes in urban areas.
Patterns in the occurrence and abundance of small mammal communities in 15 isolated patches of remnant natural and semi-natural
habitat of Porto Metropolitan Area (Portugal) were assessed against environmental characteristics (from both the patch and
the surrounding matrix) of each patch using multiple regressions and canonical correspondence analysis. Four species of common
small mammals were found: wood mouse (Apodemus sylvaticus), greater white-toothed shrew (Crocidura russula), Algerian mouse (Mus spretus) and house mouse (Mus musculus). Our results showed that both relative abundance and species richness were negatively affected by urbanization. The species
richness also displayed a negative association with the increase of forest around the patch but relative abundance showed
the opposite trend. At the species level, the relative abundance of A. sylvaticus and C. russula showed a negative association with urbanization. Our results reveal that these two species also benefit from a mosaic of
habitats and pervious areas in the surrounding matrix. The relative abundance of M. spretus and M. musculus showed a negative effect of forest area around the patch. Understanding how the increase of urbanization affects small mammals
will be particularly useful for the managers of urban landscapes, as these animals occupy a pivotal position in the ecosystems. 相似文献
877.
Chiral separation of flurbiprofen enantiomers by preparative and simulated moving bed chromatography 总被引:1,自引:0,他引:1
This study presents the chiral resolution of flurbiprofen enantiomers by preparative liquid chromatography using the simulated moving bed (SMB) technology. Flurbiprofen enantiomers are widely used as nonsteroidal anti‐inflammatory drugs, and although demonstrate different therapeutic actions, they are still marketed as a racemic mixture. The results presented here clearly show the importance of the selection of the proper solvent composition for the preparative separation of flurbiprofen enantiomers. Chiral SMB separation is carried out using a laboratory‐scale unit (the FlexSMB‐LSRE®) with six columns, packed with the Chiralpak AD® stationary phase (20 μm). Results presented include the experimental measurement of equilibrium and kinetic data for two very different solvent compositions, a traditional high hydrocarbon content [10%ethanol/90%n‐hexane/0.01% trifluoroacetic acid (TFA)] and a strong polar organic composition (100%ethanol/0.01%TFA). Experimental data, obtained using the two mobile phase compositions, are used to predict and optimize the SMB operation. After selecting 10%ethanol/90%n‐hexane/0.01%TFA as the most appropriate solvent composition, three feed concentrations of racemic flurbiprofen were considered. Using 40 g/l of racemic flurbiprofen feed solution, the purities for both outlet streams were above 99.4%, the productivity was 13.1 gfeed/(Lbed h), and a solvent consumption of 0.41 Lsolvent/gfeed was achieved. Chirality, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
878.
The vascular network is closely linked to the neural system, and an interdependence is displayed in healthy and in pathophysiological responses. How has close apposition of two such functionally different systems occurred? Here, we present a hypothesis for the evolution of the vascular network from an ancestral neural guidance system. Biological cornerstones of this hypothesis are the vascular endothelial growth factor (VEGF) protein family and cognate receptors. The primary sequences of such proteins are conserved from invertebrates, such as worms and flies that lack discernible vascular systems compared to mammals, but all these systems have sophisticated neuronal wiring involving such molecules. Ancestral VEGFs and receptors (VEGFRs) could have been used to develop and maintain the nervous system in primitive eukaryotes. During evolution, the demands of increased morphological complexity required systems for transporting molecules and cells, i.e., biological conductive tubes. We propose that the VEGF–VEGFR axis was subverted by evolution to mediate the formation of biological tubes necessary for transport of fluids, e.g., blood. Increasingly, there is evidence that aberrant VEGF-mediated responses are also linked to neuronal dysfunctions ranging from motor neuron disease, stroke, Parkinson’s disease, Alzheimer’s disease, ischemic brain disease, epilepsy, multiple sclerosis, and neuronal repair after injury, as well as common vascular diseases (e.g., retinal disease). Manipulation and correction of the VEGF response in different neural tissues could be an effective strategy to treat different neurological diseases. 相似文献
879.
Assreuy AM Pinto NV Lima Mota MR Passos Meireles AV Cajazeiras JB Nobre CB Soares PM Cavada BS 《Protein and peptide letters》2011,18(11):1107-1111
The vasorelaxant effect of the lectin of Pisum arvense (PAL) seeds was investigated in rat aorta. PAL (10-100 μg/ml) was applied on aorta rings, with or without endothelium, pre-contracted with phenylephrine (Phe; 0.1 μM). Participation of endothelium derived relaxant factors was evaluated incubating the tissue with indomethacin (10 μM), L-nitro arginine methyl ester (L-NAME, 100 μM) and tetraethylammonium (TEA, 5 mM) before addition of PAL. The role of the lectin domain was investigated by addition of PAL into tissue in presence of glucose (3x 10?? M), or N-acetyl Dglucosamine (GlcNAc; 3 x 10?? M). The importance of extracellular calcium (Ca2?e) or interaction with muscarinic receptors in the relaxant effect was evaluated by addition of PAL into aorta rings containing calcium free solution (OCa) and atropine (1 μ M), respectively. PAL induced concentration-dependent relaxation in endothelized aorta (IC50 =58.38 ± 1.87 μg/ml), which was reversed by L-NAME and glucose. The lectin effect was totally inhibited when the preparation was inserted in OCa, but not in presence of atropine. Summarizing, our data showed a relaxant effect of PAL in isolated rat aorta rings in presence of endothelium, suggestive of interaction between the lectin carbohydrate binding sites with specific receptors located in vascular endothelial cells leading to nitric oxide synthase activation. This effect seems to require Ca2?e but is independent on muscarinic receptors interaction. 相似文献
880.
Initial analysis of copy number variations in cattle selected for resistance or susceptibility to intestinal nematodes 总被引:1,自引:0,他引:1