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排序方式: 共有125条查询结果,搜索用时 15 毫秒
31.
Niels H Chavannes Juanita HJ Vernooy Tjard RJ Schermer Jan A Jacobs Mieke A Dentener Chris van Weel Onno CP van Schayck Emiel FM Wouters 《BMC pulmonary medicine》2006,6(1):1-7
Background
Although both smoking and respiratory complaints are very common, tools to improve diagnostic accuracy are scarce in primary care. This study aimed to reveal what inflammatory patterns prevail in clinically established diagnosis groups, and what factors are associated with eosinophilia.Method
Induced sputum and blood plasma of 59 primary care patients with COPD (n = 17), asthma (n = 11), chronic bronchitis (CB, n = 14) and smokers with no respiratory complaints ('healthy smokers', n = 17) were collected, as well as lung function, smoking history and clinical work-up. Patterns of inflammatory markers per clinical diagnosis and factors associated with eosinophilia were analyzed by multiple regression analyses, the differences expressed in odds ratios (OR) with 95% confidence intervals.Results
Multivariately, COPD was significantly associated with raised plasma-LBP (OR 1.2 [1.04–1.37]) and sTNF-R55 in sputum (OR 1.01 [1.001–1.01]), while HS expressed significantly lowered plasma-LBP (OR 0.8 [0.72–0.95]). Asthma was characterized by higher sputum eosinophilic counts (OR 1.3 [1.05–1.54]), while CB showed a significantly higher proportion of sputum lymphocytic counts (OR 1.5 [1.12–1.9]). Sputum eosinophilia was significantly associated with reversibility after adjusting for smoking, lung function, age, gender and allergy.Conclusion
Patterns of inflammatory markers in a panel of blood plasma and sputum cells and mediators were discernable in clinical diagnosis groups of respiratory disease. COPD and so-called healthy smokers showed consistent opposite associations with plasma LBP, while chronic bronchitics showed relatively predominant lymphocytic inflammation compared to other diagnosis groups. Only sputum eosinophilia remained significantly associated with reversibility across the spectrum of respiratory disease in smokers with airway complaints. 相似文献32.
J Kindermann Y El-Ayouti GJ Samuels CP Kubicek 《Fungal genetics and biology : FG & B》1998,24(3):298-309
Sequences of the internal transcribed spacer region 1 (ITS1) of the ribosomal DNA were used to determine the phylogenetic relationships of species of Trichoderma sect. Pachybasium. To this end, 85 strains-including all the available ex-type strains-were analyzed. Parsimony analysis demonstrated that the section is nonmonophyletic, distributing the 85 strains among three main groups that were supported by bootstrap values. Group A comprises two clades (A1 and A2), with A1 including T. polysporum, T. piluliferum, and T. minutisporum, while A2 included T. hamatum, T. pubescens, and T. strigosum in addition to species previously included in sect. Trichoderma (i.e., T. viride, T. atroviride, and T. koningii). The ex-type strain of T. fasciculatum formed a separate branch basal to clade A. Clade B contained the sect. Pachybasium members T. harzianum, T. fertile, T. croceum, T. longipile, T. strictipile, T. tomentosum, T. oblongisporum, T. flavofuscum, T. spirale, and the anamorphs of Hypocrea semiorbis and H. cf. gelatinosa. Sequence differences among clades A1, A2, and B were in the same order of magnitude as between each of them and T. longibrachiatum, which was used as an outgroup in these analyses. Sequence differences within clades A1, A2, and B were considerably smaller: in some cases (i.e., T. virens and T. flavofuscum; T. strictipile and H. cf. gelatinosa), the ITS1-sequences were identical, suggesting conspecifity. In other cases (e.g., T. crassum and T. longipile; T. harzianum, T. inhamatum, T. croceum, T. fertile, and H. semiorbis; T. hamatum and T. pubescens; and T. viride, T. atroviride, and T. koningii) differences were in the range of 1-3 nt only, suggesting a very close phylogenetic relationship. The sequence of a previously described aggressive mushroom competitor group of T. harzianum strains (Th2) was strikingly different from that of the ex-type strain of T. harzianum and closely related species and is likely to be a separate species. Copyright 1998 Academic Press. 相似文献
33.
The swi8(+) gene of Schizosaccharomyces pombe appears to be involved in the termination step of copy synthesis during mating-type (MT) switching. Mutations in swi8 confer a general mutator phenotype and, in particular, generate specific mutations in the MT region. Sequencing of the MT cassettes of the h(90) swi8-137 mutant revealed three altered sites. One is situated at the switching (smt) signal adjacent to the H1 homology box of the expression locus mat1:1. It reduces the rate of MT switching. The alteration at the smt signal arose frequently in other h(90) swi8 strains and is probably caused by gene conversion in which the sequence adjacent to the H1 box of mat2:2 is used as template. This change might be generated during the process of MT switching when hybrid DNA formation is anomalously extended into the more heterologous region flanking the H1 homology box. In addition to the gene conversion at mat1:1, two mutations were found in the H3 homology boxes of the silent cassettes mat2:2 and mat3:3. 相似文献
34.
Bror Edlund Örjan Zetterqvist Ulf Ragnarsson Lorentz Engström 《Biochemical and biophysical research communications》1977,79(1):139-144
Cyclic GMP-stimulated protein kinase from pig lung has been shown to phosphorylate synthetic peptides. The rate of phosphorylation was about one order of magnitude higher than that for mixed histones at a comparable concentration, 0.1 mM. The peptides represented sites, phosphorylatable by cyclic AMP-stimulated protein kinase, in pyruvate kinase type L from rat liver, calf thymus histone H2B and the α-subunit of rabbit muscle phosphorylase b kinase. The shortest pyruvate kinase peptide that could be phosphorylated at a significant rate by cyclic GMP-stimulated protein kinase was Arg-Arg-Ala-Ser-Val-Ala, which is one amino acid residue longer than the minimal substrate of cyclic AMP-stimulated protein kinase. The apparent Km was 0.3 mM which is about 10 times higher than that with cyclic AMP-stimulated protein kinase. The Km was only slightly decreased upon successive extension of the peptide in the N-terminal direction to Gly-Val-Leu-Arg-Arg-Ala-Ser-Val-Ala. Modification of the sequence showed the importance of two adjacent arginyl residues, and substitution of arginine for the C-terminal alanine abolished the measurable activity. Thus, it has been demonstrated that there are both differences and similarities in substrate specificity of the two protein kinases. 相似文献
35.
36.
Sellge G Lorentz A Gebhardt T Levi-Schaffer F Bektas H Manns MP Schuppan D Bischoff SC 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(1):260-267
In rodents, fibroblasts (FBs) mediate stem cell factor (SCF)-dependent growth of mast cells (MCs). In humans, SCF is mandatory for MC differentiation and survival. Other factors such as IL-3, IL-4, and nerve growth factor (NGF) act in synergism with SCF, thus enhancing proliferation and/or preventing apoptosis in MCs. In this study, we studied in vitro interactions between human MCs and human FBs, both isolated from the intestine and purified to homogeneity. In coculture with FBs, MCs survived for up to 3 wk, whereas purified MCs cultured alone died within a few days. TNF-alpha and IL-1beta, which both did not affect MC survival directly, enhanced FB-dependent MC growth. We provide evidence that FB-derived MC growth factors are soluble, heat-sensitive molecules which down-regulate MC apoptosis without enhancing MC proliferation. However, only low amounts of SCF were measured in FB-conditioned medium (<0.2 ng/ml). Moreover, blocking of SCF/c-kit interaction by anti-SCF or anti-c-kit Abs and neutralization of IL-3, IL-4, and NGF did not affect MC survival in the coculture system. In conclusion, our data indicate that human FBs promote survival of human MCs by mechanisms independent of SCF, IL-3, IL-4, and NGF. Such interactions between MCs and FBs may explain why MCs accumulate at sites of inflammatory bowel disease and intestinal fibrosis. 相似文献
37.
Human intestinal mast cells are capable of producing different cytokine profiles: role of IgE receptor cross-linking and IL-4 总被引:6,自引:0,他引:6
Lorentz A Schwengberg S Sellge G Manns MP Bischoff SC 《Journal of immunology (Baltimore, Md. : 1950)》2000,164(1):43-48
Mast cells are recognized as a new type of immunoregulatory cells capable of producing different cytokines. So far, little is known about the cytokine profile of mature human mast cells isolated from intestinal tissue and cultured in the presence of stem cell factor (SCF). We observed that these cells express the proinflammatory cytokines TNF-alpha, IL-1 beta, IL-6, IL-8, IL-16, and IL-18 without further stimulation. Both IgE-dependent and IgE-independent agonists (e.g., Gram-negative bacteria) enhanced expression of TNF-alpha. Another set of cytokines consisting of IL-3, IL-5, IL-9, and IL-13 was expressed following activation by IgE receptor cross-linking. If mast cells were cultured in the presence of IL-4 and SCF, the production and release of IL-3, IL-5, and IL-13 was increased up to 4-fold compared with mast cells cultured with SCF alone. By contrast, IL-6 expression was completely blocked in response to culture with IL-4. In summary, our data show that mature human mast cells produce proinflammatory cytokines that may be up-regulated following triggering with IgE-independent agonists such as bacteria, whereas activation by IgE receptor cross-linking results in the expression of Th2-type cytokines. IL-4 enhances the expression of Th2-type cytokines but does not affect or even down-regulates proinflammatory cytokines. 相似文献
38.
Background
Unravelling the path from genotype to phenotype, as it is influenced by an organism's environment, is one of the central goals in biology. Gene expression profiling by means of microarrays has become very prominent in this endeavour, although resources exist only for relatively few model systems. As genomics has matured into a comparative research program, expression profiling now also provides a powerful tool for non-traditional model systems to elucidate the molecular basis of complex traits. 相似文献39.
40.
Soares MP Gaya LG Lorentz LH Batistel F Rovadoscki GA Ticiani E Zabot V Di Domenico Q Madureira AP Pértile SF 《Genetics and molecular research : GMR》2011,10(3):1942-1947
Artificial insemination has been used to improve production in Brazilian dairy cattle; however, this can lead to problems due to increased inbreeding. To evaluate the effect of the magnitude of inbreeding coefficients on predicted transmitting abilities (PTAs) for milk traits of Holstein and Jersey breeds, data on 392 Holstein and 92 Jersey sires used in Brazil were tabulated. The second-degree polynomial equations and points of maximum or minimal response were estimated to establish the regression equation of the variables as a function of the inbreeding coefficients. The mean inbreeding coefficient of the Holstein bulls was 5.10%; this did not significantly affect the PTA for percent milk fat, protein percentage and protein (P = 0.479, 0.058 and 0.087, respectively). However, the PTAs for milk yield and fat decreased significantly after reaching inbreeding coefficients of 6.43 (P = 0.034) and 5.75 (P = 0.007), respectively. The mean inbreeding coefficient of Jersey bulls was 6.45%; the PTAs for milk yield, fat and protein, in pounds, decreased significantly after reaching inbreeding coefficients of 15.04, 9.83 and 12.82% (P < 0.001, P = 0.002, and P = 0.001, respectively). The linear regression was only significant for fat and protein percentages in the Jersey breed (P = 0.002 and P = 0.005, respectively). The PTAs of Holstein sires were more affected by smaller magnitudes of inbreeding coefficients than those of Jersey sires. It is necessary to monitor the inbreeding coefficients of sires used for artificial insemination in breeding schemes in Brazil, since the low genetic variability of the available sires may lead to reduced production. 相似文献