Results 141 to 150 of about 26,693 (166)

Interference of 7,8-dihydroneopterin with peroxynitrite-mediated reactions

Biochemical and Biophysical Research Communications, 2004
By in vitro studies 7,8-dihydroneopterin, which is secreted by macrophages stimulated by interferon-gamma, was reported to be a radical scavenger as well as a prooxidative agent depending on the experimental settings. In this study, we investigated the interference of 7,8-dihydroneopterin with peroxynitrite mediated reactions by different analytical ...
Karl, Oettl, Joachim, Greilberger, Sergey, Dikalov, Gilbert, Reibnegger   +3 more
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Protection of erythrocytes by the macrophage synthesized antioxidant 7,8 dihydroneopterin

Free Radical Research, 2001
Neopterin and the reduced form, 7,8-dihydroneopterin (78NP) are pteridines released from macrophages when stimulated with gamma-interferon in vivo. The role of 78NP in inflammatory response is unknown though neopterin has been used clinically as a marker of immune cell activation, due to its very fluorescent nature.
Gieseg, S. P., Maghzal, G., Glubb, D.
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Oxidation of 7,8-Dihydroneopterin by Hypochlorous Acid Yields Neopterin

Biochemical and Biophysical Research Communications, 2000
In vitro, interferon-gamma stimulates primate monocytes/macrophages to produce the pteridines neopterin and 7,8-dihydroneopterin. These pteridines are capable of modulating the oxidative potential of reactive species. Neopterin is pro-oxidative whereas 7, 8-dihydroneopterin is an effective antioxidant. In the presence of oxygen, 7,8-dihydroneopterin is
B, Widner, C, Mayr, B, Wirleitner, D, Fuchs   +3 more
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Photodimerization of 7,8‐Dihydroneopterin in Aqueous Solution Under UV‐A Irradiation

Photochemistry and Photobiology, 2010
Abstract7,8‐Dihydroneopterin (H2Nep) is secreted during the oxidative burst of stimulated macrophages. The photochemistry of H2Nep was investigated in neutral aqueous solutions exposed to UV‐A radiation (320–400 nm) at room temperature. The kinetics were followed by UV/Vis spectrophotometry and HPLC, whereas the photoproducts were analyzed by ...
Mariana, Vignoni, Mariana P, Serrano, Esther, Oliveros, Andrés H, Thomas   +3 more
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Spin Trapping Study of Antioxidant Properties of Neopterin and 7,8-Dihydroneopterin

Biochemical and Biophysical Research Communications, 1997
Previously, it has been shown that pteridine derivatives are capable of modulating the action of free radicals and both prooxidant and antioxidant properties have been described. However, the mechanism of manifestation of these properties is still unclear. We studied the radical scavenging properties of 7,8-dihydroneopterin and neopterin using the spin
K, Oettl, S, Dikalov, H J, Freisleben, W, Mlekusch, G, Reibnegger   +4 more
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Effects of neopterin and 7,8‐dihydroneopterin on hypoxia‐induced renal erythropoietin production

European Journal of Haematology, 1999
Abstract: Activation of the human cellular immune system is associated with greatly increased formation of the pteridines neopterin and 7,8‐dihydroneopterin. It has been postulated that pteridines play a role in the pathogenesis of the anaemia of inflammation.
H, Pagel, J, Fandrey, W, Schobersberger, D, Fuchs, W, Jelkmann   +4 more
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Dissociation of neopterin and 7,8-dihydroneopterin from plasma components before HPLC analysis

Journal of Chromatography B, 2008
Measurement of plasma neopterin by HPLC with fluorescence detection is used clinically as a marker of immune cell activation in the management of a number of disease pathologies. HPLC analysis of neopterin requires the acidic removal of plasma proteins but we have found that 7,8-dihydroneopterin is oxidised to neopterin with varying yield.
Elizabeth A, Flavall, Elizabeth M, Crone, Grant A, Moore, Steven P, Gieseg   +3 more
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Influence of neopterin and 7,8-dihydroneopterin on the replication of Coxsackie type B5 and influenza A viruses

Medical Microbiology and Immunology, 2006
Pteridine derivatives neopterin and 7,8-dihydroneopterin are produced by human macrophages and dendritic cells upon stimulation with interferon-gamma (IFN-gamma) and therefore become detectable in increased amounts in humans during cell-mediated (Th1-type) immune response.
Olga, Bratslavska, Diana, Platace, Edvīns, Miklasevics, Dietmar, Fuchs, Agris, Martinsons   +4 more
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Foam cell formation but not oxLDL cytotoxicity is inhibited by CD36 down regulation by the macrophage antioxidant 7,8-dihydroneopterin

The International Journal of Biochemistry & Cell Biology, 2021
Cluster of differentiation 36 (CD36) is a key scavenger receptor in the control of macrophage uptake of oxidised low-density lipoproteins (oxLDL). CD36 expression levels are not down regulated by intracellular cholesterol but are upregulated by oxidised low density lipoprotein (oxLDL) leading to the formation of lipid loaded foam cells, a major ...
Nooshin Ghodsian, Anthony Yeandle, Steven P. Gieseg   +2 more
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trans -Activation of the HIV Type 1 Promoter by 7,8-Dihydroneopterin in Vitro

AIDS Research and Human Retroviruses, 1997
Infection with human immunodeficiency virus type 1 and 2 is associated with elevated concentrations of neopterin, released in large quantities by human macrophages on stimulation with interferon gamma. Evidence has suggested a potential role of neopterin derivatives in oxygen radical-mediated processes.
G, Baier-Bitterlich, D, Fuchs, R, Zangerle, P A, Baeuerle, E R, Werner, F, Fresser, F, Uberall, G, Baier, H, Wachter   +8 more
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