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151.
152.
Munnikes RJ Muis C Boersma M Heijmans-Antonissen C Zijlstra FJ Huygen FJ 《Mediators of inflammation》2005,2005(6):366-372
The aim of this paper is to determine the involvement of tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-6 in intermediate CRPS 1 as locally formed mediators of inflammation. In this study, 25 patients with proven CRPS 1 (Bruehl criteria) were included. All patients participated in one of our earlier studies during the acute stage of their disease. After the disease developed into an intermediate stage, both the disease activity and the profile of inflammatory mediators were reevaluated. Disease activity and impairment were determined by means of a visual analogue scale, the McGill Pain Questionnaire, the difference in volume and temperature between the involved and uninvolved extremities, and the reduction in active range of motion of the involved extremity. Suction blisters were made on the involved and uninvolved extremities for measurement of IL-6 and TNF-alpha. A significant improvement in signs and symptoms of impairment was found. However, the levels of IL-6 and TNF-alpha in blister fluid in the involved extremity versus uninvolved extremity were still significantly raised. Although signs and symptoms are significantly improved, proinflammatory cytokines are still increased in CRPS 1 affected extremities during the intermediate stage of the disease. This indicates that the initiation and sustained development of the disease are only partially affected by proinflammatory cytokines. Follow-up in the chronic stage is necessary to draw more definite conclusions about the existence of a supposed relation between clinical signs and symptoms and the level of proinflammatory cytokines. 相似文献
153.
N-terminal acetylation in the yeast Saccharomyces cerevisiae is catalysed by any of three N-terminal acetyltransferases (NAT), NatA, NatB, and NatC, which contain the catalytic subunits Ard1p, Nat3p and Mak3p, respectively. Yeast 6-phosphofructo-2-kinase (PFK2) was found to be acetylated at the amino acid lysine 3. The Lys3-Arg mutant was not acetylated and the mutation causes a slight decrease in enzyme activity. PFK2 from yeast cells exposed to hypo-osmotic stress is known to be phosphorylated at Ser8 and Ser652 (Dihazi et al., 2001a). We have taken a mass spectrometric approach to investigate the influence of PFK2 acetylation on its phosphorylation. Wild-type PFK2 and the Lys3-Arg mutant were purified from hypo-osmotically stressed cells and analysed with MALDI-TOF MS for phosphorylation. Wild-type PFK2 without any tag sequence was found to be acetylated and two times phosphorylated at the N-terminal peptide T(1-40) carrying the acetylation. The same results were observed with C-terminally His-tagged PFK2. When the His-tag was added to the N-terminus of the protein PFK2, acetylation was found to be incomplete and only one phosphate was incorporated in the peptide T(1-41). The Lys3-Arg mutant of PFK2 was not at all post-translationally modified at the N-terminal peptide. Our data indicate that Lys3 acetylation affects the N-terminal phosphorylation of PFK2 under hypo-osmotic stress. 相似文献
154.
Jürgen?MierschEmail author Dieter?Neumann Sieglinde?Menge Felix?B?rlocher Renate?Baumbach Olaf?Lichtenberger 《Mycological Progress》2005,4(3):185-194
Growth of three strains of Tetracladium marchalianum was inhibited by Cd-, and, to a lesser extent, by Cu-and Zn-chloride. In the presence of 50 μM Cd(II), all strains increased
total thiol and glutathione production to 6, 11, and 21 μmoles · mg−1 dry mass, respectively. Cd(II) also induced the synthesis of one to several compounds reacting with 5,5′-dithio-bis-(2-nitrobenzoic
acid). In order to identify buffer-soluble thiolic compounds other than cysteine, γ-EC and γ-ECG (glutathione) were analyzed
and confirmed by mass spectrometry. No water soluble sulfides were detectable in any of the culture filtrates, but Cd(II)
exposure at a concentration of 50 μM raised sulfide levels in the mycelia of two of the strains between 3 and 7-fold, Cu(II)
and Zn(II) had no effect. Energy Dispersive X-ray-analysis (EDX) and Electron Spectrometry-Images (ES-I) of one strain revealed
increased levels of Cu and Zn in the cytoplasm and even higher levels in vacuolar precipitates. Zn and Cu are accumulated
in the vacuoles as polyphosphates, identified by Electron Energy Loss-Spectrometry (EELS). Cd was found only in the vacuoles. 相似文献
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156.
Salemi S Aeschlimann A Reisch N Jüngel A Gay RE Heppner FL Michel BA Gay S Sprott H 《Biochemical and biophysical research communications》2005,338(2):1012-1017
Opioid receptors (OR) are widely expressed in the central nervous system (CNS). Opioid antinociception might be initiated by activation of OR outside the CNS, indicating targeting of peripheral OR could be useful in the treatment of chronic pain. This study was designed to detect OR in skin tissues of healthy volunteers at both mRNA and protein levels. Skin samples from 10 healthy individuals were investigated. Total isolated RNAs were reverse transcribed, amplified and quantified by real-time PCR. Tissue and skin fibroblast OR protein was detected by immunohistochemistry, Western blot, and immunofluorescence. All skin tissue samples expressed delta- (DOR) and kappa-OR (KOR) mRNAs. Using immunohistochemistry, DOR and KOR were localized in skin fibroblast-like and mononuclear cells. Skin fibroblasts in culture expressed DOR and KOR mRNA. Using immunofluorescence, both DOR and KOR proteins were expressed predominantly on the cell membrane with minor staining in the cytoplasm. We suggest that enhanced expression of DOR and KOR in skin justifies the exploration of selective novel delta and kappa agonists for local pain treatment. 相似文献
157.
158.
Cornman RS Burke JM Wesselingh RA Arnold ML 《Evolution; international journal of organic evolution》2004,58(12):2669-2681
Studies of natural hybridization have suggested that it may be a creative stimulus for adaptive evolution and speciation. An important step in this process is the establishment of fit recombinant genotypes that are buffered from subsequent recombination with unlike genotypes. We used molecular markers and a two-generation sampling strategy to infer the extent of recombination in a Louisiana iris hybrid zone consisting predominantly of Iris fulva-type floral phenotypes. Genotypic diversity was fairly high, indicating that sexual reproduction is frequent relative to clonal reproduction. However, we observed strong spatial genetic structure even after controlling for clonality, which implies a low level of pollen and seed dispersal. We therefore used cluster analysis to explore the hypothesis that the fulva-type hybrids are an admixture of groups between which there has been limited recombination. Our results indicate that several such groups are present in the population and are strongly localized spatially. This spatial pattern is not attributable strictly to a lack of mating opportunities between dissimilar genotypes for two reasons: (1) relatedness of flowering pairs was uncorrelated with the degree of overlap in flowering, and (2) paternity analysis shows that pollen movement among the outcross fraction occurred over large distances, with roughly half of all paternity attributed to pollen flow from outside the population. We also found evidence of strong inbreeding depression, indicated by contrasting estimates of the rate of self-fertilization and the average inbreeding coefficient of fulva-type hybrids. We conclude that groups of similar hybrid genotypes can be buffered from recombination at small spatial scales relative to pollen flow, and selection against certain recombinant genotypes may be as important as or more important than clonal reproduction and inbreeding. 相似文献
159.
160.