The Experts below are selected from a list of 105 Experts worldwide ranked by ideXlab platform
Daniel G. Miller - One of the best experts on this subject based on the ideXlab platform.
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Steroidal Nonspecific Esterase metabolism of N‐hydroxy‐2‐acetylaminofluorene: evidence for selective activation by the cellular reductant NADPH
Journal of leukocyte biology, 1992Co-Authors: Margaretha Lund-pero, Ronald W. Pero, Daniel G. MillerAbstract:The significance of the Nonspecific Esterases of human mononuclear leukocytes (HMLs) in arylamine carcinogenesis is suggested by data showing that the metabolically formed hydroxamic acid derivative of 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, is a substrate for this class of enzymes. A viable cell assay for the Nonspecific Esterases using alpha-naphthyl acetate as substrate is described, and data showing this activity to be sensitive to already known substrates for HML Esterases as measured by three previously described assays are presented. All four assays of the same Esterase activity are shown to be highly sensitive to up- and down-regulation by addition of NADPH or NADP to viable HML cultures. Selective activation of a purified rabbit Nonspecific Esterase by NADPH, but not by the other cellular reductants, NADH and glutathione, was demonstrated. Cytosols prepared from normal human tissue samples of liver, breast, colon, and brain were also activated by the presence of NADPH. These data do not indicate that steroidal Nonspecific Esterases are redox-modulated by the presence of mixed disulfides in their structure. Instead, they support the direct and specific influence of NADPH as a widespread activator of Esterase activity by a mechanism not yet understood.
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steroidal Nonspecific Esterase metabolism of n hydroxy 2 acetylaminofluorene evidence for selective activation by the cellular reductant nadph
Journal of Leukocyte Biology, 1992Co-Authors: Margaretha Lundpero, Ronald W. Pero, Daniel G. MillerAbstract:The significance of the Nonspecific Esterases of human mononuclear leukocytes (HMLs) in arylamine carcinogenesis is suggested by data showing that the metabolically formed hydroxamic acid derivative of 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, is a substrate for this class of enzymes. A viable cell assay for the Nonspecific Esterases using alpha-naphthyl acetate as substrate is described, and data showing this activity to be sensitive to already known substrates for HML Esterases as measured by three previously described assays are presented. All four assays of the same Esterase activity are shown to be highly sensitive to up- and down-regulation by addition of NADPH or NADP to viable HML cultures. Selective activation of a purified rabbit Nonspecific Esterase by NADPH, but not by the other cellular reductants, NADH and glutathione, was demonstrated. Cytosols prepared from normal human tissue samples of liver, breast, colon, and brain were also activated by the presence of NADPH. These data do not indicate that steroidal Nonspecific Esterases are redox-modulated by the presence of mixed disulfides in their structure. Instead, they support the direct and specific influence of NADPH as a widespread activator of Esterase activity by a mechanism not yet understood.
W Strober - One of the best experts on this subject based on the ideXlab platform.
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Wright-Giemsa and Nonspecific Esterase staining of cells.
Current protocols in cytometry, 2001Co-Authors: W StroberAbstract:This appendix provides two protocols for staining cells. The stains used in the Wright-Giemsa protocol, the Romanowsky stains, are a mixture of methylene blue (and other closely related thiazine dyes) and eosin. The staining protocol is a two-stage method that allows for a more intense staining of the nuclei than would be possible if the Wright and Giemsa stains were mixed together. In the second protocol, Nonspecific Esterase stain are used to identify cell types containing Esterases that have a characteris termediate that can be coupled with a substance, hexazotized pararosaniline, to yield a colored precipitate. Thus, this staining reaction can be used to identify monocytes/macrophages in cell preparations.
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Wright-Giemsa and Nonspecific Esterase staining of cells.
Current protocols in immunology, 2001Co-Authors: W StroberAbstract:This appendix provides two protocols for staining cells. The stains used in the Wright-Giemsa protocol, the Romanowsky stains, are a mixture of methylene blue (and other closely related thiazine dyes) and eosin. The staining protocol is a two-stage method that allows for a more intense staining of the nuclei than would be possible if the Wright and Giemsa stains were mixed together. In the second protocol, Nonspecific Esterase stain are used to identify cell types containing Esterases that have a characteristic ability to split esters under particular conditions. In the staining method given here, the substrate, a-naphthyl butyrate, is incubated with cells under conditions in which Esterases present in monocytes/macrophages split the substrate to yield an intermediate that can be coupled with a substance, hexazotized pararosaniline, to yield a colored precipitate. Thus, this staining reaction can be used to identify monocytes/macrophages in cell preparations.
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Current Protocols in Immunology - Wright‐Giemsa and Nonspecific Esterase Staining of Cells
Current protocols in immunology, 2000Co-Authors: W StroberAbstract:This appendix provides two protocols for staining cells. The stains used in the Wright-Giemsa protocol, the Romanowsky stains, are a mixture of methylene blue (and other closely related thiazine dyes) and eosin. The staining protocol is a two-stage method that allows for a more intense staining of the nuclei than would be possible if the Wright and Giemsa stains were mixed together. In the second protocol, Nonspecific Esterase stain are used to identify cell types containing Esterases that have a characteris termediate that can be coupled with a substance, hexazotized pararosaniline, to yield a colored precipitate. Thus, this staining reaction can be used to identify monocytes/macrophages in cell preparations.
Ronald W. Pero - One of the best experts on this subject based on the ideXlab platform.
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Steroidal Nonspecific Esterase metabolism of N‐hydroxy‐2‐acetylaminofluorene: evidence for selective activation by the cellular reductant NADPH
Journal of leukocyte biology, 1992Co-Authors: Margaretha Lund-pero, Ronald W. Pero, Daniel G. MillerAbstract:The significance of the Nonspecific Esterases of human mononuclear leukocytes (HMLs) in arylamine carcinogenesis is suggested by data showing that the metabolically formed hydroxamic acid derivative of 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, is a substrate for this class of enzymes. A viable cell assay for the Nonspecific Esterases using alpha-naphthyl acetate as substrate is described, and data showing this activity to be sensitive to already known substrates for HML Esterases as measured by three previously described assays are presented. All four assays of the same Esterase activity are shown to be highly sensitive to up- and down-regulation by addition of NADPH or NADP to viable HML cultures. Selective activation of a purified rabbit Nonspecific Esterase by NADPH, but not by the other cellular reductants, NADH and glutathione, was demonstrated. Cytosols prepared from normal human tissue samples of liver, breast, colon, and brain were also activated by the presence of NADPH. These data do not indicate that steroidal Nonspecific Esterases are redox-modulated by the presence of mixed disulfides in their structure. Instead, they support the direct and specific influence of NADPH as a widespread activator of Esterase activity by a mechanism not yet understood.
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steroidal Nonspecific Esterase metabolism of n hydroxy 2 acetylaminofluorene evidence for selective activation by the cellular reductant nadph
Journal of Leukocyte Biology, 1992Co-Authors: Margaretha Lundpero, Ronald W. Pero, Daniel G. MillerAbstract:The significance of the Nonspecific Esterases of human mononuclear leukocytes (HMLs) in arylamine carcinogenesis is suggested by data showing that the metabolically formed hydroxamic acid derivative of 2-acetylaminofluorene, N-hydroxy-2-acetylaminofluorene, is a substrate for this class of enzymes. A viable cell assay for the Nonspecific Esterases using alpha-naphthyl acetate as substrate is described, and data showing this activity to be sensitive to already known substrates for HML Esterases as measured by three previously described assays are presented. All four assays of the same Esterase activity are shown to be highly sensitive to up- and down-regulation by addition of NADPH or NADP to viable HML cultures. Selective activation of a purified rabbit Nonspecific Esterase by NADPH, but not by the other cellular reductants, NADH and glutathione, was demonstrated. Cytosols prepared from normal human tissue samples of liver, breast, colon, and brain were also activated by the presence of NADPH. These data do not indicate that steroidal Nonspecific Esterases are redox-modulated by the presence of mixed disulfides in their structure. Instead, they support the direct and specific influence of NADPH as a widespread activator of Esterase activity by a mechanism not yet understood.
Wei-feng Chen - One of the best experts on this subject based on the ideXlab platform.
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Nonspecific Esterase released from thymic macrophages accumulates in the apoptotic thymocytes: an indication for this enzyme participating in the clearance of apoptotic thymocytes.
European Journal of Immunology, 2002Co-Authors: Ji-ming Feng, Jiang-sheng Wu, Anthony T. Campagnoni, Wei-feng ChenAbstract:: In the mouse thymus, a large number of developing thymocytes die through apoptosis each day. It has been proposed that thymic macrophages are responsible for clearance of the massive number of thymocytes that die through apoptosis. The detailed clearance mechanism by which macrophages remove the apoptotic cells is not clear. Our in vitro studies in this report show that Nonspecific Esterase (NSE), a cytochemical marker enzyme of macrophages, was secreted from thymic macrophages as a consequence of stimulation by interaction with thymocytes, and the Esterase accumulated in these macrophage-binding thymocytes (MBT). TUNEL staining demonstrated that these MBT were undergoing apoptosis. The inability to exclude eosin Y and the presence of pores on the plasma membrane were further evidence for the disintegration of these MBT. In vivo, the release of NSE was evident by the presence of NSE activity in the extracellular space between the macrophages and apoptotic thymocytes under the transmission electron microscope after dexamethasone injection, which causes massive apoptosis of thymocytes. Inhibition study showed that the inhibition of NSE delayed the MBT progressing to the late apoptotic phase. These results suggest that the NSE released from macrophages is involved in the clearance of apoptotic thymocytes.
Zhu Jiazhen - One of the best experts on this subject based on the ideXlab platform.
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Localization and quantification of the Nonspecific Esterase in injured skin for timing of wounds
Forensic science international, 1992Co-Authors: Wang Dachun, Zhu JiazhenAbstract:Abstract Histochemical quantification of the Nonspecific Esterase (NSE) in injured skin was performed using histochemical demonstration of the enzyme and a microspectrophotometric scanning technique on specimens taken from 32 Hartley guinea-pigs and 8 cases of human skin wounds. In all antemortem incisions and lacerations, including those made at the agonal state, NSE activity could be observed in the dermal tissue of the wound edge. The enzyme activity increases with the antemortem duration of the injuries. Both total content and mean concentration of NSE in the wound edge between antemortem and postmortem wound groups differ significantly ( P P
