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Sympathoadrenergic pathways are crucial to the communication between the nervous system and the immune system. The present review addresses emerging issues in the adrenergic modulation of immune cells, including: the specific pattern of adrenoceptor expression on immune cells and their role and changes upon cell differentiation and activation; the production and utilization of noradrenaline and adrenaline by immune cells themselves; the dysregulation of adrenergic immune mechanisms in disease and their potential as novel therapeutic targets. A wide array of sympathoadrenergic therapeutics is currently used for non-immune indications, and could represent an attractive source of non-conventional immunomodulating agents. 相似文献
3.
Rita Businaro Evandro Fioretti Lorenzo Fumagalli Gennaro Citro Gabriella De Renzis Franca Ascoli 《The Histochemical journal》1988,20(4):187-193
Summary In addition to bovine pancreatic trypsin inhibitor (BPTI), three BPTI-related molecular forms (isoinhibitors I, II and III) were isolated from bovine lung by affinity chromatography on immobilized trypsin and subsequently purified by Fast Protein Liquid Chromatography. These inhibitors are identical to the isoinhibitors previously isolated from bovine spleen. Their localization in bovine lung was studied by immunohistochemical techniques, using two different immunoglobulin preparations, selectively recognizing BPTI or the other molecular forms.BPTI-related immunoreactivity was found to be restricted to isolated cells, often identified as mast cells by Toluidine Blue staining. In contrast, isoinhibitor-related immunoreactivity, which also occurs in the mast cells, is present in a number of other cell types. These types include: (i) the smooth muscle cells of different calibre vessels, (ii) the ciliated cells of the bronchial epithelium and the related mucus, and (iii) many cells at alveolar level.Comparison of these data with previous results obtained for bovine spleen suggest multiple physiological roles for these inhibitors. 相似文献
4.
Annarosa Selli Franca Crociani Diego Matteuzzi Giorgio Crisetig 《Current microbiology》1986,13(1):33-38
Feedback inhibition of crude and purified extracts of homoserine dehydrogenase and threonine deaminase activities in the genusBifidobacterium was studied. Homoserine dehydrogenase was partially or completely inhibited byl-threonine, and a marked inhibitory effect byl-isoleucine on threonine deaminase was observed. In the speciesBifidobacterium cuniculi high levels ofl-valine reversed the inhibitory effect ofl-isoleucine. The -aminobutyric acid-resistant mutant Ru 326/106 of the speciesB. ruminale, overproducer ofl-isoleucine, had a derepressed homoserine dehydrogenase and a lesser feedback inhibition byl-threonine. Homoserine dehydrogenase appeared to be in bifids specifically NAD dependent. The regulatory mechanisms of aspartate family amino acid biosynthesis in bifidobacteria was discussed. 相似文献
5.
Increase of the glycolytic rate in human resting fibroblasts following serum stimulation. The possible role of the fructose-2,6-bisphosphate 总被引:2,自引:0,他引:2
We report that glycolysis in human quiescent fibroblasts stimulated by serum addition is increased, and that the changes of the metabolic route reflect the activity of the phosphofructokinase. A possible role of fructose-2,6-bisphosphate as a positive modulator of the key enzyme is proposed. 相似文献
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7.
Elisabetta Zennaro Ilaria Ciabatti Francesca Cutruzzola Rosanna D'Alessandro Maria Chiara Silvestrini 《FEMS microbiology letters》1993,109(2-3):243-250
Abstract The expression of nitrite reductase has been tested in a wild-type strain of Pseudomonas aeruginosa (Pao1) as a function of nitrate concentration under anaerobic and aerobic conditions. Very low levels of basal expression are shown under non-denitrifying conditions (i.e. absence of nitrate, in both aerobic and anaerobic conditions); anaerobiosis is not required for high levels of enzyme production in the presence of nitrate. A Pseudomonas aeruginosa strain, mutated in the nitrite reductase gene, has been obtained by gene replacement. This mutant, the first of this species described up to now, is unable to grow under anaerobic conditions in the presence of nitrate. The anaerobic growth can be restored by complementation with the wild-type gene. 相似文献
8.
C. Olivari Maria Chiara Pugliarello Franca Rasi-Caldogno Maria Ida De Michelis 《Plant biology (Stuttgart, Germany)》1993,106(1):13-19
The aqueous two-phase partitioning technique was utilized to isolate a plasma membrane (PM) fraction from etiolated seedlings of Arabidopsis thaliana. The purification procedure adopted yielded a fraction highly enriched in PM as compared to inner membranes, with a recovery of about 30%, as judged from the activities of PM markers such as vanadate-sensitive ATPase, FC binding and UDP-glucose sterol glucosyltransferase. The purified PM fraction displayed vanadate-sensitive H+ pumping activity. Its purity was confirmed by the biochemical characteristics of its ATPase activity assayed in the absence of Ca2+: sensitivity to vanadate (IC50 ca. 1 μM), Mg2+-dependence, insensitivity to molybdate, oligomycin and nitrate, pH optimum at 6.6. The PM H+-ATPase activity was stimulated by fusicoccin and by a controlled treatment of the PM with trypsin. In both cases stimulation was much stronger on the activity assayed at pH 7.5 than on the activity at pH 6.6. Moreover, neither fusicoccin nor the treatment with trypsin stimulated the portion of activity (30 to 40% at pH 7.5) which decayed upon preincubation of the PM in assay medium without ATP. 相似文献
9.
Jennifer L. Wright Heather A. Stewart Ivette Candanedo Evan D'Alessandro Maria Estevanez Rafael J. Araújo 《Biotropica》2023,55(2):299-305
We conducted visual fish surveys in coexisting mangrove-coral (CMC) habitats in Panama to analyze the effect of coral presence in mangrove habitats on the fish assemblage. Our study revealed that CMC habitats harbor distinct fish assemblages compared to mangrove habitats without coral, with greater species richness and increased herbivore abundance. Abstract in Spanish is available with online material. 相似文献
10.
The presence of keratinophilic fungi was revealed by sampling the air of Pavia (Italy) from March 1981 to February 1982. The species isolated were: Chrysosporium indicum, Geomyces pannorum var.pannorum, Microsporum gypseum, Myceliophtora vellerea and Trichophyton terrestre. Several filamentous fungi tolerating high levels of cycloheximide were also recovered. 相似文献