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排序方式: 共有437条查询结果,搜索用时 15 毫秒
81.
Tobias Ruck Stefanie Bock Steffen Pfeuffer Christina B.Schroeter Derya Cengiz Paul Marciniak Maren Lindner Alexander Herrmann Marie Liebmann Stjepana Kovac Lukas Gola Leoni Rolfes Marc Pawlitzki Nils Opel Tim Hahn Udo Dannlowski Thomas Pap Felix Luessi Julian A.Schreiber Bernhard Wünsch Tanja Kuhlmann Guiscard Seebohm Bjrn Tackenberg Patricia Seja Frank Dring Erhard Wischmeyer Achmet Imam Chasan Johannes Roth Luisa Klotz Gerd Meyer zu Hrste Heinz Wiendl Tobias Marschall Stefan Floess Jochen Huehn Thomas Budde Tobias Bopp Stefan Bittner Sven G.Meuth 《Cell research》2022,32(1):72-88
It remains largely unclear how thymocytes translate relative differences in T cell receptor (TCR) signal strength into distinct developmental programs that driv... 相似文献
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84.
Luigi Servillo Domenico Castaldo Alfonso Giovane Rosario Casale Nunzia DOnofrio Domenico Cautela Maria Luisa Balestrieri 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):991-998
Background
Ophthalmic acid (OPH), γ-glutamyl-L-2-aminobutyryl-glycine, a tripeptide analogue of glutathione (GSH), has recently captured considerable attention as a biomarker of oxidative stress in animals. The OPH and GSH biosynthesis, as well as some biochemical behaviors, are very similar. Here, we sought to investigate the presence of OPH in plants and its possible relationship with GSH, known to possess multiple functions in the plant development, growth and response to environmental changes.Methods
HPLC-ESI-MS/MS analysis was used to examine the occurrence of OPH in leaves from various plant species, and flours from several plant seeds. Different types of oxidative stress, i.e., water, dark, paraquat, and cadmium stress, were induced in rye, barley, oat, and winter wheat leaves to evaluate the effects on the levels of OPH and its metabolic precursors.Results
OPH and its dipeptide precursor, γ-glutamyl-2-aminobutyric acid, were found to occur in phylogenetically distant plants. Interestingly, the levels of OPH were tightly associated with the oxidative stress tested. Levels of OPH precursors, γ-glutamyl-2-aminobutyric acid and 2-aminobutyric acid, the latter efficiently formed in plants via biosynthetic pathways absent in the animal kingdom, were also found to increase during oxidative stress.Conclusions
OPH occurs in plants and its levels are tightly associated with oxidative stress.General significance
OPH behaves as an oxidative stress marker and its biogenesis might occur through a biochemical pathway common to many living organisms. 相似文献85.
Maria Marino Silvana Spagnuolo Matteo Cavallini Fulvia Terenzi Maria Teresa Mangiantini Silvia Leoni 《Cellular signalling》1996,8(8):555-559
We investigate the effect of EGF on IP3 production, PLCγ phosphorylation, calcium transients in rat hepatocytes isolated in quiescent liver (G0 phase of cell cycle) and at 4 h (G1 phase of cell cycle) and 24 h (M phase of cell cycle) after partial hepatectomy. Our results show that EGF does not utilize IP3 and calcium as its signal transduction molecules when the hepatocytes are in vivo stimulated to entry in the cell cycle. In particular the growth factor does not phosphorylate PLCγ and induces a decrease in IP3 content. These data suggest that EGF utilizes different signal transduction to send information from receptor to nucleus during PH with respect to the quiescent liver. 相似文献
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S Leoni M T Mangiantini F Pulcinelli S Spagnuolo 《Bollettino della Società italiana di biologia sperimentale》1983,59(4):444-449
Cholesterol and phospholipid content, and phospholipid composition (sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylinositol, phosphatidylethaolamine) were assayed in rat liver microsomes during regeneration, foetal development and pregnancy. Cholesterol was assayed using Liebermann-Buchard reagent; the phospholipid extract was separated by thin-layer chromatography. While in pregnancy no changes were observed, during foetal development and liver regeneration there was a significative decrease of cholesterol/phospholipid ratio, and of phosphatidylcholine content. Moreover, in developing liver microsomes, there is also a significative increase of sphingomyelin and phosphatidylserine + phosphatidylinositol. 相似文献
88.
P Leoni A Olivieri R Centurioni M Montillo 《Bollettino della Società italiana di biologia sperimentale》1983,59(8):1089-1095
Ten bone marrow suspensions have been cryopreserved by a Programmed Freezer Planer R 201. Total cellularity, viability, differential myelograms, cytochemical pattern and CFU-GM growth "in vitro", have been evaluated on the cellular suspensions both before and after 1 and 18 months of storage in liquid nitrogen. Total cellular recovery and viable cell recovery were satisfactory, cellular loss being due, almost entirely to death of the more mature cells. NASDA reaction did not vary after freezing, on the contrary peroxidase reaction and overall PAS reaction showed respectively a slight and an almost complete disappearance. LAP reaction was not valuable, after freezing, because of the more mature myeloid cell loss. CFU-GM recovery was satisfactory and clusters and colonies growth in methylcellulose appeared quite similar before and after 1 and 18 months of storage at very low temperature. Our cryopreservation technique cannot prevent some cellular loss or some qualitative cellular damage, but colonizing ability is almost completely preserved. 相似文献
89.
Patricia Leoni Roger T. Dean 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》1983,762(3):378-389
Secretion of lysosomal enzymes by human monocytes in response to various stimuli and the effect of conditioned media from lymphocytes and neutrophils was studied. Monocytes were found to release β-glucosaminidase in response to NH4Cl and to particles (zymosan, opsonised zymosan, asbestos and latex), but do not respond to some soluble stimuli like formyl-methionyl-leucyl-phenylalanine, phorbol myristate acetate, cytochalasin B, concanavalin A and . Neutrophil conditioned medium or neutrophil components did not have any effect on secretion. When treated with lymphokines the cells are more responsive, especially to zymosan. Even through there are similarities in the secretory activities of mouse macrophages and human monocytes, there are several differences both in the quantity of the response and in the mechanisms involved. 相似文献
90.
Plasma membrane changes associated with rat liver regeneration 总被引:3,自引:0,他引:3
G Bruscalupi G Curatola G Lenaz S Leoni M T Mangiantini L Mazzanti S Spagnuolo A Trentalance 《Biochimica et biophysica acta》1980,597(2):263-273
The lipid composition and fluidity of plasma membranes have been studied at different stages of liver regeneration (4, 15 and 24 h after surgery). The phospholipid and fatty acid composition is not modified, whereas the cholesterol/phospholipid ratio is lower with respect to control membranes. The modification of the physical properties of the membranes has been studied directly by EPR analysis and indirectly by temperature dependence and cooperativity of some membrane-bound enzymes (Mg2+-ATPase, (Na+ + K+)-ATPase and 5'nucleotidase). Surgical operation or anaesthesia alone causes an early increase in fluidity; such an effect appears to be markedly reduced at a later stage. There seems to be a marked effect of regeneration on plasma membrane fluidity 15 h after partial hepatectomy when several parameters--surface fluidity, cholesterol/phospholipid ratio, and 5'-nucleotidase activity in the presence of concanavalin A -- are modified and indicate an increase in membrane fluidity. It is suggested that this modification of membrane properties could be related to the proliferative process. 相似文献