CCL

Összesen 7 találat.
#/oldal:
Részletezés:
Rendezés:

1.

001-es BibID:BIBFORM028691
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:The effect of time of addition of glutamine or nucleosides on proliferation of rat cervical lymph-node T-lymphocytes after stimulation by concanavalin A / Zsuzsa Szondy, Eric A. Newsholme
Dátum:1991
ISSN:0264-6021
Megjegyzések:Addition of concanavalin A to T-cell lymphocytes from rat cervical lymph nodes increases the activity of glutaminase within 1 h and those of carbamoyl-phosphate synthase II and aspartate transcarbamoylase within 3 h. There was a similar time course for the effects of concanavalin A on rates of glutamine utilization, which was increased within 1 h, and on pyrimidine nucleotide synthesis, which was increased by 40% at 2 h and by 100% at 3 h. 2. A delay in the addition of glutamine to the culture medium after addition of concanavalin A caused a decrease in [3H]thymidine incorporation only after 4-6 h. In the absence of glutamine, delay in addition of guanosine or inosine caused a decrease in [3H]thymidine incorporation only after 6-8 h after the addition of concanavalin A. 3. In contrast, a delay in addition of adenosine or uridine to the culture medium had an immediate effect (i.e. within 2 h) on the rate of incorporation of [3H]thymidine. It is suggested that adenosine and uridine have specific effects on proliferation via specific receptors for these nucleosides in the membrane.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
külföldön készült közlemény
Megjelenés:The Biochemical Journal. - 278 : 2 (1991), p. 471-474. -
További szerzők:Newsholme, Eric A.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:

2.

001-es BibID:BIBFORM028690
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:The effect of various concentrations of nucleobases, nucleosides or glutamine on the incorporation of [3H]thymidine into DNA in rat mesenteric-lymph-node lymphocytes stimulated by phytohaemagglutinin / Zsuzsa Szondy, Eric A. Newsholme
Dátum:1990
ISSN:0264-6021
Megjegyzések:The rate of [3H]thymidine incorporation into DNA was measured in phytohaemagglutinin-stimulated lymph-node lymphocytes of the rat. 2. Addition of nucleobases or nucleosides to culture medium that already contained 0.2 mM-glutamine had a small stimulatory effect on incorporation. At lower concentrations of glutamine, adenosine (even at 1 microM) caused a marked increase in the rate of incorporation. 3. In the absence of added glutamine, addition of nucleosides or nucleobases markedly increased the rate of incorporation: nucleosides were more effective than nucleobases; and the rate of proliferation in the presence of 10 microM-adenosine plus 10 microM-uridine was similar to that in the presence of optimal concentrations of glutamine. 4. The rate of incorporation was dramatically decreased by an inhibitor of the pathway of pyrimidine nucleotide synthesis de novo. Addition of the pyrimidine nucleosides completely overcame the inhibition; addition of the pyrimidine nucleobases was much less effective. 5. These results indicate that, for proliferation of lymphocytes, glutamine is not essential and can be partially or totally replaced by nucleosides and, to some extent, by nucleobases.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
külföldön készült közlemény
Megjelenés:The Biochemical Journal. - 270 : 2 (1990), p. 437-440. -
További szerzők:Newsholme, Eric A.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:

3.

001-es BibID:BIBFORM028689
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:The rate of the AMP/adenosine substrate cycle in concanavalin- A-stimulated rat lymphocytes / Zsuzsa Szondy, Eric A. Newsholme
Dátum:1989
ISSN:0264-6021
Megjegyzések:The effect of adenosine on the metabolism of prelabelled adenine nucleotides was investigated in concanavalin-A-stimulated rat lymphocytes. Adenosine in the presence of the adenosine deaminase inhibitor, deoxycoformycin, caused a 2-fold increase in the ATP concentration. This effect was, in part, countereacted by an increased rate of adenine nucleotide catabolism, which could be explained by a stimulation of AMP deaminase (EC 3.5.4.6). At the same time a continuous rate of labelled adenosine production was found, which was not affected by the increased ATP concentration and which could only be detected by the trapping effect of a high concentration of added unlabelled adenosine. It is concluded that the rate of the substrate cycle between AMP and adenosine is low (1.9 +/- 0.2 nmol/h per 10(7) cells) in comparison to the rate of AMP deamination.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
külföldön készült közlemény
Megjelenés:The Biochemical Journal. - 261 : 3 (1989), p. 739-742. -
További szerzők:Newsholme, Eric A.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:

4.

001-es BibID:BIBFORM028688
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:The effect of glutamine concentration on the activity of carbamoyl-phosphate synthase II and on the incorporation of [3H]thymidine into DNA in rat mesenteric lymphocytes stimulated by phytohaemagglutinin / Zsuzsa Szondy, Eric A. Newsholme
Dátum:1989
Megjegyzések:The maximum catalytic activities of carbamoyl-phosphate synthase II, a limiting enzyme for pyrimidine nucleotide synthesis, are very much less than those of glutaminase, a limiting enzyme for glutamine utilization, in lymphocytes and macrophages; and the flux through the pathway for pyrimidine formation de novo is only about 0.4% of the rate of glutamine utilization by lymphocytes. The Km of synthase II for glutamine is about 16 microM and the concentration of glutamine necessary to stimulate lymphocyte proliferation half-maximally is about 21 microM. This agreement suggests that the importance of glutamine for these cells is provision of nitrogen for biosynthesis of pyrimidine nucleotides (and probably purine nucleotides). However, the glutamine concentration necessary for half-maximal stimulation of glutamine utilization (glutaminolysis) by the lymphocytes is 2.5 mM. The fact that the rate of glutamine utilization by lymphocytes is markedly in excess of the rate of the pathway for pyrimidine nucleotide synthesis de novo and that the Km and 'half-maximal concentration' values are so different, suggests that the glutaminolytic pathway is independent of the use of glutamine nitrogen for pyrimidine synthesis.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
külföldön készült közlemény
Megjelenés:The Biochemical Journal.. - 261 : 3 (1989), p. 979-983. -
További szerzők:Newsholme, Eric A.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:

5.

001-es BibID:BIBFORM028766
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:Inhibition of activation-induced apoptosis of thymocytes by all-trans- and 9-cis-retinoic acid is mediated via retinoic acid receptor alpha / Zsuzsa Szondy, Uwe Reichert, Jean-Michel Bernardon, Serge Michel, Réka Tóth, Éva Karászi, László Fésüs
Dátum:1998
ISSN:0264-6021
Megjegyzések:Thymocytes can be induced to undergo apoptotic cell death by activation through the T-cell receptor (TCR). This process requires macromolecular synthesis and has been shown to be inhibited by retinoic acids (RAs). Two groups of nuclear receptors for RAs have been identified: retinoic acid receptors (RARs) and retinoid X receptors (RXRs). All-trans-RA is the high-affinity ligand for RARs, and 9-cis-RA additionally binds to RXRs with high affinity. Because 9-cis-RA is much more potent in inhibiting TCR-mediated death than all-trans-RA, it was suggested that RXRs participate in the process. In the present study various synthetic retinoid analogues were used to address this question further. The results presented suggest that the inhibitory effect of RAs on activation-induced death of thymocytes is mediated via RARalpha, because (1) it can be reproduced by various RARalpha analogues both in vitro and in vivo, (2) the effect of RAs can be inhibited by the addition of an RARalpha antagonist, (3) CD4+CD8+thymocytes, which die on TCR stimulation, express RARalpha. Stimulation of RARgamma, in contrast, enhances the activation-induced death of thymocytes and inhibits its prevention by RARalpha stimulation. RXR co-stimulation suspends this inhibitory effect of RARgamma and permits the preventive function of RARalpha on activation-induced death. Our results suggest a complex interaction between the various isoforms of retinoid receptors and demonstrate that low (physiological) concentrations of all-trans-RA do not affect the activation-induced death of thymocytes because the RARalpha-mediated inhibitory and the RARgamma-mediated enhancing pathways are in balance, whereas if 9-cis-RA is formed, additional stimulation of RXRs permits the inhibitory action of RARalpha.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
egyetemen (Magyarországon) készült közlemény
Megjelenés:Biochemical Journal. - 331 : 3 (1998), p. 767-774. -
További szerzők:Reichert, Uwe Bernardon, Jean Michel Michel, Serge Révészné Tóth Réka (1969-) (molekuláris biológus, biokémikus) Karászi Éva Fésüs László (1947-) (orvos biokémikus)
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:

6.

001-es BibID:BIBFORM028719
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:The 2-chlorodeoxyadenosine-induced cell death signalling pathway in human thymocytes is different from that induced by 2-chloroadenosine / Zsuzsa Szondy
Dátum:1995
ISSN:0264-6021
Megjegyzések:2-chloroadenosine induced DNA fragmentation and cell death in human thymocytes primarily by Ca(2+)-dependent mechanisms. Incubation of human thymocytes with 2-chlorodeoxyadenosine (5-1000 nM) also induced cell death (apoptosis) which was dependent on macromolecule synthesis and involved activation of an endonuclease which was inhibited by Zn2+. The effect of 2-chlorodeoxyadenosine was prevented by addition of dipyridamole, a strong nucleoside transport inhibitor, or of deoxycytidine, previously shown to compete for uptake by deoxycytidine kinase. 2-Chlorodeoxyadenosine-induced apoptosis did not involve increases in the cytosolic Ca2+ concentration, but required the presence of intracellular Ca2+. It was not inhibited by activators of protein kinase C previously shown to inhibit Ca(2+)-dependent cell death. Addition of 2-chlorodeoxyadenosine induced an increase in the amount of p53 in human thymocytes, while 2-chloroadenosine had no effect. These data suggest that 2-chloroadenosine and 2-chlorodeoxyadenosine induce cell death in human thymocytes via different signalling pathways.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
egyetemen (Magyarországon) készült közlemény
Megjelenés:Biochemical Journal. - 311 : 2 (1995), p. 585-588. -
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:

7.

001-es BibID:BIBFORM028692
Első szerző:Szondy Zsuzsanna (molekuláris sejtbiológus, biokémikus)
Cím:Adenosine stimulates DNA fragmentation in human thymocytes by Ca(2+)-mediated mechanisms / Zsuzsa Szondy
Dátum:1994
ISSN:0264-6021
Megjegyzések:Incubation of human thymocytes with an optimum concentration of adenosine and its receptor site agonist, 2-chloroadenosine, induced increases in intracellular cyclic AMP (cAMP) (from a resting 0.6 +/- 0.1 to 4.1 +/- 0.2 pmol/10(7) cells within 5 min) and Ca2+ (from the resting 85 +/- 7 nM to a peak of 210 +/- 25 nM) levels and resulted in internucleosomal DNA fragmentation and cell death (apoptosis). Other adenosine analogues were also effective at inducing DNA fragmentation, the order of potency being 2-p-(carboxyethylphenylethylamino)-5'-carboxyamidoadenosine < 5'-(N-ethylcarboxamide)adenosine < or = cyclopentyladenosine < 2-chloroadenosine (2-CA). 2-CA treatment (with an optimum concentration of 40 microM) selectively depleted a thymocyte subpopulation (15-20% of the total cells) which expressed higher levels of the CD3 molecule and which was found mainly in the CD4+CD8+ double positive immature thymocyte population. DNA fragmentation was prevented by the addition of actinomycin D or cycloheximide to the thymocyte suspension, indicating that this process required both mRNA and protein synthesis. Endonuclease activation and cell killing were dependent on an early, sustained increase in cytosolic Ca2+ concentration, most of which was of extracellular origin and was a result of an adenosine-induced inositol trisphosphate release. Other agents known to elevate intracellular cAMP levels by different mechanisms failed to induce similar DNA fragmentation, but enhanced the effect of adenosine. This suggested a supporting role for cAMP in adenosine-induced DNA fragmentation. Phorbol dibutyrate, a protein kinase. C activator, previously shown to inhibit Ca(2+)-dependent DNA fragmentation and cell killing in human thymocytes [McConkey, Hartzell, Jondal and Orrenius (1989) J. Biol. Chem. 264, 13399-13402], at 60 ng/ml concentration also prevented adenosine-induced DNA fragmentation when added prior to adenosine. This suggested a complex cross-talk between the adenosine-triggered signal transduction cascade and the activation state of protein kinase C in regulating apoptosis of human thymocytes.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
egyetemen (Magyarországon) készült közlemény
Megjelenés:Biochemical Journal. - 304 : 3 (1994), p. 877-885. -
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Rekordok letöltése1 
Corvina könyvtári katalógus v8.2.27 © 2023 Monguz kft. Minden jog fenntartva.