The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Rachel Schoumacker - One of the best experts on this subject based on the ideXlab platform.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Aline Robert Hazotte, Jean-luc Le QuéréAbstract:Olfactory Mucosa can metabolize odorants through various enzymatic mechanisms participating in their clearance and therefore in the termination of the Olfactory signal. Preliminary ex-vivo studies using headspace-GC revealed the formation of volatile metabolites when odorant molecules were injected above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first five minutes of contact between the odorant and the Mucosa, thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique (PTR-MS) we have been able for the first time to investigate the first moments of the enzymatic process of the metabolic capacity of ex-vivo rat Olfactory Mucosa in real time. Using various odorous substrates, we demonstrated that they can be metabolized by an ex-vivo Olfactory Mucosa within seconds, producing volatile metabolites. Significance for human olfaction has to be investigated and will be discussed.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Aline Robert Hazotte, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Jean-luc Le QuéréAbstract:Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies. 7. International conference on proton transfer reaction mass spectrometry and its applications
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real time monitoring of the metabolic capacity of ex vivo rat Olfactory Mucosa by proton transfer reaction mass spectrometry ptr ms
Analytical and Bioanalytical Chemistry, 2016Co-Authors: Rachel Schoumacker, Aline Roberthazotte, Jean-marie Heydel, Philippe Faure, Jeanluc Le QuereAbstract:Olfactory Mucosa (OM) can metabolise odorant volatile organic compounds through various enzymatic mechanisms to produce odorous or non-odorous metabolites. Preliminary ex vivo studies using headspace-gas chromatography (HS-GC) revealed the formation of metabolites when odorant molecules were injected in the headspace above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first 5 min of contact between the odorant and the Mucosa; thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique with a proton transfer reaction instrument (PTR-MS), we have been able, for the first time, to investigate the first moments of the enzymatic process of the metabolic capacity of ex vivo rat Olfactory Mucosa in real time. Using ethyl acetate as a model volatile odorous substrate, we demonstrated here for the first time that this odorant could be metabolised by an ex vivo Olfactory Mucosa within seconds, producing ethanol as metabolite.
Jean-marie Heydel - One of the best experts on this subject based on the ideXlab platform.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Aline Robert Hazotte, Jean-luc Le QuéréAbstract:Olfactory Mucosa can metabolize odorants through various enzymatic mechanisms participating in their clearance and therefore in the termination of the Olfactory signal. Preliminary ex-vivo studies using headspace-GC revealed the formation of volatile metabolites when odorant molecules were injected above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first five minutes of contact between the odorant and the Mucosa, thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique (PTR-MS) we have been able for the first time to investigate the first moments of the enzymatic process of the metabolic capacity of ex-vivo rat Olfactory Mucosa in real time. Using various odorous substrates, we demonstrated that they can be metabolized by an ex-vivo Olfactory Mucosa within seconds, producing volatile metabolites. Significance for human olfaction has to be investigated and will be discussed.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Aline Robert Hazotte, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Jean-luc Le QuéréAbstract:Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies. 7. International conference on proton transfer reaction mass spectrometry and its applications
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real time monitoring of the metabolic capacity of ex vivo rat Olfactory Mucosa by proton transfer reaction mass spectrometry ptr ms
Analytical and Bioanalytical Chemistry, 2016Co-Authors: Rachel Schoumacker, Aline Roberthazotte, Jean-marie Heydel, Philippe Faure, Jeanluc Le QuereAbstract:Olfactory Mucosa (OM) can metabolise odorant volatile organic compounds through various enzymatic mechanisms to produce odorous or non-odorous metabolites. Preliminary ex vivo studies using headspace-gas chromatography (HS-GC) revealed the formation of metabolites when odorant molecules were injected in the headspace above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first 5 min of contact between the odorant and the Mucosa; thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique with a proton transfer reaction instrument (PTR-MS), we have been able, for the first time, to investigate the first moments of the enzymatic process of the metabolic capacity of ex vivo rat Olfactory Mucosa in real time. Using ethyl acetate as a model volatile odorous substrate, we demonstrated here for the first time that this odorant could be metabolised by an ex vivo Olfactory Mucosa within seconds, producing ethanol as metabolite.
Philippe Faure - One of the best experts on this subject based on the ideXlab platform.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Aline Robert Hazotte, Jean-luc Le QuéréAbstract:Olfactory Mucosa can metabolize odorants through various enzymatic mechanisms participating in their clearance and therefore in the termination of the Olfactory signal. Preliminary ex-vivo studies using headspace-GC revealed the formation of volatile metabolites when odorant molecules were injected above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first five minutes of contact between the odorant and the Mucosa, thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique (PTR-MS) we have been able for the first time to investigate the first moments of the enzymatic process of the metabolic capacity of ex-vivo rat Olfactory Mucosa in real time. Using various odorous substrates, we demonstrated that they can be metabolized by an ex-vivo Olfactory Mucosa within seconds, producing volatile metabolites. Significance for human olfaction has to be investigated and will be discussed.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Aline Robert Hazotte, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Jean-luc Le QuéréAbstract:Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies. 7. International conference on proton transfer reaction mass spectrometry and its applications
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real time monitoring of the metabolic capacity of ex vivo rat Olfactory Mucosa by proton transfer reaction mass spectrometry ptr ms
Analytical and Bioanalytical Chemistry, 2016Co-Authors: Rachel Schoumacker, Aline Roberthazotte, Jean-marie Heydel, Philippe Faure, Jeanluc Le QuereAbstract:Olfactory Mucosa (OM) can metabolise odorant volatile organic compounds through various enzymatic mechanisms to produce odorous or non-odorous metabolites. Preliminary ex vivo studies using headspace-gas chromatography (HS-GC) revealed the formation of metabolites when odorant molecules were injected in the headspace above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first 5 min of contact between the odorant and the Mucosa; thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique with a proton transfer reaction instrument (PTR-MS), we have been able, for the first time, to investigate the first moments of the enzymatic process of the metabolic capacity of ex vivo rat Olfactory Mucosa in real time. Using ethyl acetate as a model volatile odorous substrate, we demonstrated here for the first time that this odorant could be metabolised by an ex vivo Olfactory Mucosa within seconds, producing ethanol as metabolite.
Eva B. Brittebo - One of the best experts on this subject based on the ideXlab platform.
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CYP2A5-mediated activation and early ultrastructural changes in the Olfactory Mucosa : studies on 2,6-dichlorophenyl methylsulfone.
Drug metabolism and disposition: the biological fate of chemicals, 2005Co-Authors: Anna Franzén, Carina Carlsson, Veronica Hermansson, Matti A. Lang, Eva B. BritteboAbstract:2,6-Dichlorophenyl methylsulfone (2,6-diClPh-MeSO2) is a potent Olfactory toxicant reported to induce endoplasmic reticulum (ER) stress, caspase activation, and extensive cell death in mice. The aim of the present study was to examine cytochrome P450 (P450)-dependent bioactivation, nonprotein sulfhydryl (NP-SH) levels, and early ultrastructural changes in mouse Olfactory Mucosa following an i.p. injection of 2,6-diClPh-MeSO2 (32 mg/kg). A high covalent binding of 2,6-diClPh-14C-MeSO2 in Olfactory Mucosa S9 fraction was observed, and the CYP2A5/CYP2G1 substrates coumarin and dichlobenil significantly decreased the binding, whereas the CYP2E1 substrate chlorzoxazone had no effects. An increased bioactivation was detected in liver microsomes of mice pretreated with pyrazole, known to induce CYP2A4, 2A5, 2E1, and 2J, and addition of chlorzoxazone reduced this binding. 2,6-DiClPh-14C-MeSO2 showed a marked covalent binding to microsomes of recombinant yeast cells expressing mouse CYP2A5 or human CYP2A6 compared with wild type. One and 4 h after a single injection of 2,6-diClPh-MeSO2, the NP-SH levels in the Olfactory Mucosa were significantly reduced compared with control, whereas there was no change in the liver. Ultrastructural studies revealed that ER, mitochondria, and secretory granules in nonneuronal cells were early targets 1 h after injection. We propose that lesions induced by 2,6-diClPh-MeSO2 in the mouse Olfactory Mucosa were initiated by a P450-mediated bioactivation in the Bowman's glands and depletion of NP-SH levels, leading to disruption of ion homeostasis, organelle swelling, and cell death. The high expression of CYP2A5 in the Olfactory Mucosa is suggested to play a key role for the tissue-specific toxicity induced by 2,6-diClPh-MeSO2.
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Isomer-specific Bioactivation and Toxicity of Dichlorophenyl Methylsulphone in Rat Olfactory Mucosa
Toxicologic pathology, 2003Co-Authors: Anna Franzén, Ingvar Brandt, Carina Carlsson, Eva B. BritteboAbstract:This study aimed to explain the isomer- and site-specific toxic effects of dichlorophenyl methylsulphone in the Olfactory Mucosa of rats. A single ip dose of the 2,6-chlorinated isomer (16 or 65 ...
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Long-term effects in the Olfactory Mucosa and bulb following systemic exposure to chemicals
2002Co-Authors: Ulrika Bergström, Anders Fredriksson, Eva B. BritteboAbstract:Long-term effects in the Olfactory Mucosa and bulb following systemic exposure to chemicals
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Methimazole Toxicity in Rodents: Covalent Binding in the Olfactory Mucosa and Detection of Glial Fibrillary Acidic Protein in the Olfactory Bulb
Toxicology and applied pharmacology, 1999Co-Authors: Ulrika Bergman, Eva B. BritteboAbstract:Methimazole is an antithyroid drug reported to affect the sense of smell and taste in humans. The aim of the present study was to examine the distribution and effects of methimazole on the Olfactory system in rodents. Autoradiography showed a selective covalent binding of 3H-labeled methimazole in the Bowman's glands in the Olfactory Mucosa, bronchial epithelium in the lungs, and centrilobular parts of the liver following an iv injection in mice. Histopathology showed an extensive lesion in the Olfactory Mucosa that was efficiently repaired 3 months after two consecutive ip doses of methimazole. The effect of methimazole on various brain regions was studied by determining levels and location of glial fibrillary acidic protein (GFAP). The results showed a threefold increase of GFAP in the Olfactory bulb 2 weeks after treatment with methimazole whereas no change was observed 4 days after treatment. Pretreatment of mice with thyroxine did not protect against the methimazole-induced toxicity in the Olfactory Mucosa and bulb. In contrast, pretreatment with the cytochrome P450 inhibitor metyrapone completely prevented the covalent binding and toxicity of methimazole in the Olfactory Mucosa and bulb. The present results suggest that the methimazole-induced toxicity in the Olfactory Mucosa is mediated by a cytochrome P450-dependent metabolic activation of the compound into reactive metabolites that are bound to various tissues including the Olfactory Mucosa. The increase of GFAP in the Olfactory bulb of methimazole-treated mice is suggested to be a secondary phenomenon due to the primary damage in the Olfactory Mucosa.
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Dichlobenil in the fetal and neonatal mouse Olfactory Mucosa
Toxicology, 1995Co-Authors: Catalina Eriksson, Eva B. BritteboAbstract:Abstract The irreversible binding and toxicity of the Olfactory toxicant dichlobenil in the mouse perinatal Olfactory Mucosa were examined by autoradiography and histopathology. In the Olfactory Mucosa of adult mice the irreversible binding of [ 14 C]dichlobenil-derived radioactivity is confined to the Bowman's glands. The results in this study showed a low irreversible binding of [ 14 C]dichlobenil-derived radioactivity in the fetal Olfactory Mucosa from day 17 of gestation and a markedly increased binding after birth in accord with the development of the Bowman's glands. No morphologicalchanges were observed in the Olfactory Mucosa of 1- or 4-day-old neonates given s.c. injections with dichlobenil 12 mg/kg but in 8- or 11-day-old mice given 12 or 25 mg/kg, scattered necrotic Bowman's glands occurred in the dorsomedial Olfactory region 24 h after administration. In adult male mice dosed i.p. with dichlobenil a more extensive toxicity in the Bowman's glands was observed. The low toxicity of dichlobenil in the postnatal Olfactory Mucosa, despite a high irreversible binding at this site, may possibly be related to the cell proliferation in the developing Olfactory Mucosa leading to replacement of damaged cells.
Jean-luc Le Quéré - One of the best experts on this subject based on the ideXlab platform.
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Aline Robert Hazotte, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Jean-luc Le QuéréAbstract:Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies. 7. International conference on proton transfer reaction mass spectrometry and its applications
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Aroma volatile metabolites at Olfactory Mucosa level evidenced by in vitro PTR-Tof-MS studies
2016Co-Authors: Rachel Schoumacker, Etienne Sémon, Jean-marie Heydel, Philippe Faure, Aline Robert Hazotte, Jean-luc Le QuéréAbstract:Olfactory Mucosa can metabolize odorants through various enzymatic mechanisms participating in their clearance and therefore in the termination of the Olfactory signal. Preliminary ex-vivo studies using headspace-GC revealed the formation of volatile metabolites when odorant molecules were injected above a fresh explant of rat Olfactory Mucosa. However, this method did not allow accessing the data during the first five minutes of contact between the odorant and the Mucosa, thus limiting the Olfactory biological significance. Using a direct-injection mass spectrometry technique (PTR-MS) we have been able for the first time to investigate the first moments of the enzymatic process of the metabolic capacity of ex-vivo rat Olfactory Mucosa in real time. Using various odorous substrates, we demonstrated that they can be metabolized by an ex-vivo Olfactory Mucosa within seconds, producing volatile metabolites. Significance for human olfaction has to be investigated and will be discussed.
