Florence Persat - Academia.edu (original) (raw)
Papers by Florence Persat
Journal of Biological Chemistry
Neutral glycosphingolipids of the metacestodes of Echinococcus multilocularis, an animal and huma... more Neutral glycosphingolipids of the metacestodes of Echinococcus multilocularis, an animal and human parasite, were resolved by high performance thin layer chromatography into 12 fractions. Nine of these fractions were permethylated, analyzed by electron impact-mass spectrometry, and submitted to methylation analysis by gas chromatography-mass spectrometry. Native fractions were analyzed by liquid secondary ion-mass spectrometry and degraded sequentially by exoglycosidases. In addition to a previously described galactosylceramide, a di-, a tri-, and a tetragalactosyl-ceramide having Gal beta 1-6Gal internal linkages were characterized. This type of carbohydrate chain has been described in glycolipids of a marine mollusk, Turbo cornutus (Matsubara, T., and Hayashi, A. (1981) J. Biochem. (Tokyo), 89, 645-650). In addition two novel fucolipids were found with the following structures: Fuc alpha 1-3Gal beta 1-6Gal-Cer and Gal beta 1-6(Fuc alpha 1-3)Gal beta 1-6Gal-Cer. Ceramides contained...
Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 1988
l. Lipid distribution of Echinococcus multilocularis was as follows; neutral lipid 48.5%; glycoli... more l. Lipid distribution of Echinococcus multilocularis was as follows; neutral lipid 48.5%; glycolipid 8.4%; and phospholipid 43.0%.
Journal de mycologie médicale, 2013
In the end of May 2012, a meeting of the group "sérodiagnostic fongique" of the "S... more In the end of May 2012, a meeting of the group "sérodiagnostic fongique" of the "Société française de mycologie médicale" had concerned quality controls to use, in particular, in the follow-up of Elisa techniques. A preliminary investigation showed that the internal quality controls (CIQ), according to the terms defined by the accreditation, were not systematically used. In June, was published the new guide of the COFRAC SH-GTA-06 on quality controls, this text being applicable on July 1st, 2012. It incited the working group to formulate proposals on the choice of the CIQ for antigen and antibody Elisa in the aspergillosis serodiagnosis. Informations on the external evaluations of the quality (EEQ) have also been given to better define for what we can expect from it. All these controls will allow every laboratory to better master the used techniques and their conditions of realization. A strengthened dialogue between the users and the manufacturers should incite ...
La Revue du praticien, Jan 30, 2008
Journal of medical microbiology, 2000
The in-vivo activity of amphotericin B and itraconazole against a clinical isolate of Aspergillus... more The in-vivo activity of amphotericin B and itraconazole against a clinical isolate of Aspergillus terreus was determined in a murine model of disseminated aspergillosis. MICs of amphotericin B and itraconazole for the strain, determined by an NCCLS-based technique, were 2 microg/ml and 1 microg/ml, respectively. Mice infected intravenously were treated with either itraconazole (50 or 100 mg/kg/day) or amphotericin B 4.5 mg/kg/day for 10 days. Treatment with both doses of itraconazole significantly prolonged the survival rates compared with those for untreated mice. In comparison, mortality rate and median survival time were identical for mice treated with amphotericin B and for mice given no therapy, indicating that the strain was highly resistant to amphotericin B in this model. Analysis of sterol composition showed that the major sterol was ergosterol. This suggests that amphotericin B resistance was not related to a modified sterol profile.
Biochimica et biophysica acta, Jan 6, 1995
Free ceramides were isolated and purified from the metacestodes of Echinococcus multilocularis. T... more Free ceramides were isolated and purified from the metacestodes of Echinococcus multilocularis. Two different fractions were obtained by preparative thin-layer chromatography. Their structure was determined by gas chromatography and electron impact mass spectrometry of trimethylsilylated derivatives. The ceramide with the higher thin-layer chromatographic migration rate contained exclusively erythro-sphinganine associated with saturated C16, C18 and very-long-chain fatty acids (up to C30) and unsaturated C24 fatty acid. The second ceramide contained 90.3% sphingosine and 9.7% sphinganine associated with saturated C16 and C24 and unsaturated C18 and C24 fatty acids. These findings were discussed with regard to the structure and metabolic pathway of neutral and acid glycosphingolipids found in the metacestodes.
Molecular and Biochemical Parasitology, 1990
Neutral and acid glycosphingolipids of Echinococcus multilocularis metace:,todes that were obtain... more Neutral and acid glycosphingolipids of Echinococcus multilocularis metace:,todes that were obtained after intraperitoneal infection of Meriones unguiculatus have been analyzed by thin layer chromatography. Neutral and acid glycosphingolipids accounted for 95% and 5% of total glycosphingolipids, respectively. 12 different fracticns were observed in the neutral glycosphingolipids extracts of the parasite. The most important was a monohexosylceramide fraction accounting for 56.4% of neutral glycosphingolipids. 9 different fractions were detected in gangliosides (acid glycosphingolipids). The fact that these glycosphingolipids were specific to the parasite was established by the analysis of different cell populations of the host. Glycosphingolipids were purified from control and parasite-infected gerbil blood cells as well as from peritoneal exudate cells of healthy gerbils after a non-specific immunostimulation. The chromatograms obtained with these extracts were totally different from the parasite. In addition, parasitosis was found to have no effect on the host blood cell glycosphingolipids.
Molecular and Biochemical Parasitology, 1990
Monohexosylceramides of Echinococcus multilocularis metacestodes have been isolated and analyzed ... more Monohexosylceramides of Echinococcus multilocularis metacestodes have been isolated and analyzed by thin-layer chromatography, gas-liquid chromatography and mass spectrometry. 90.9% of the parasite fraction was galactosylceramide; glucosylceramide was present at only 9.1%. The most important fatty acids were normal C&.. and C&a fatty acids. The hydroxylated fatty acids of the ceramide part constituted 20.1% of the total, their major constituents were Cur.. and C&a. The sphinganine accounted for 70.4% of long-chain bases, phytosphingosine and sphingosine were also detected. The importance of the long chain fatty acids and the presence of sphinganine in the monohexosylceramide fraction were discussed.
Journal of Medical Microbiology, 1999
An animal model of disseminated aspergillosis was used to test the in-vivo activity of itraconazo... more An animal model of disseminated aspergillosis was used to test the in-vivo activity of itraconazole against four isolates of Aspergillus fumigatus. Two reference isolates of A. fumigatus known to be resistant to itraconazole in vitro and in vivo were used as control isolates, and two new isolates were tested under the same conditions. For each isolate MICs for itraconazole and amphotericin B were determined by an NCCLS-based method. Mice infected intravenously were treated either with itraconazole 100 mg/ kg/day or amphotericin B 4.5 mg/kg/day for 10 days. Amphotericin B showed good invivo activity against all four isolates. For one strain, which had a low in-vitro MIC for itraconazole, in-vivo therapy with itraconazole prolonged the survival of mice and reduced fungal burdens in organs compared with untreated controls. In mice infected with a strain with a high MIC of >16 mg/L, itraconazole neither prolonged survival nor reduced fungal load in organs compared with controls. It is concluded that there is a relationship between MIC and treatment outcome in mice for A. fumigatus infection.
Journal of Antimicrobial Chemotherapy, 2001
The antifungal susceptibility profiles of four ASPERGILLUS: fumigatus isolates, recovered at diff... more The antifungal susceptibility profiles of four ASPERGILLUS: fumigatus isolates, recovered at different times from a patient treated with itraconazole for a pulmonary ASPERGILLUS: infection, were evaluated. Itraconazole MICs against two pre-treatment isolates were 0.5 mg/L, whilst two later isolates, recovered after at least 4 months of itraconazole therapy, had itraconazole MICs of >16 mg/L. In vivo susceptibilities to itraconazole and amphotericin B were tested in a murine model of disseminated aspergillosis. Treatment efficacy was evaluated by examining mortality rates and qualitative cultures of brain and kidneys. Itraconazole therapy significantly prolonged survival of mice infected with the initial isolates as compared with untreated controls. The third isolate was only partially susceptible to itraconazole in vivo, and the fourth isolate was highly resistant. The four isolates were typed by random amplified polymorphic DNA (RAPD) with four different primers. RAPD patterns obtained with each of them were identical, suggesting that the same strain was recovered over time and had acquired resistance to itraconazole.
Journal of Antimicrobial Chemotherapy, 1994
Journal of Antimicrobial Chemotherapy, 2000
Journal of Antimicrobial Chemotherapy, 1999
Abstract The MICs of amphotericin B and itraconazole for 230 isolates of Aspergillus spp., compri... more Abstract The MICs of amphotericin B and itraconazole for 230 isolates of Aspergillus spp., comprising 156 Aspergillus fumigatus, 20 Aspergillus terreus, 22 Aspergillus flavus, 17 Aspergillus nidulans and 15 Aspergillus niger, were determined by a broth microdilution ...
Glycoconjugate Journal, 1993
FEMS Microbiology Letters, 2004
The 14-3-3 protein was shown to be present into the parasitophorous vacuole of Toxoplasma gondii-... more The 14-3-3 protein was shown to be present into the parasitophorous vacuole of Toxoplasma gondii-infected human monocyte cells and in the excreted/secreted antigens (ESA). The ESA 14-3-3 protein migrates electrophoretically as the cytosol and the main membranous 14-3-3 isoforms. The excretion/secretion of 14-3-3 was not sensitive to cycloheximide, a protein synthesis inhibitor, even at a concentration which inhibited the production of 14-3-3 inside the tachyzoites. Recombinant 14-3-3/GST protein was used to test the presence of 14-3-3 antibodies in different human sera. A positive immunoreactivity was observed with sera corresponding to acute toxoplasmosis and a possible involvement of 14-3-3 in host immunity is discussed.
European Journal of Clinical Microbiology & Infectious Diseases, 2005
European Journal of Cancer, 1992
Two different treatments with repeated oral high doses of itraconazole were tested for 10 days in... more Two different treatments with repeated oral high doses of itraconazole were tested for 10 days in 20 neutropenic patients, 10 receiving 400 mg per day and 10 receiving 600 mg per day. In each group 5 patients were treated for acute leukaemia and 5 patients were recipients of autologous bone-marrow transplantation (ABMT). Itraconazole plasma concentrations were assayed by high-performance liquid chromatography. Statistical analysis disclosed a significant interaction between the dispensed dose and the patient types. The difference between the two doses of itraconazole was greater in the ABMT than in the leukaemia patients. After 10 days at 600 mg per day all the ABMT patients had an itraconazole plasma concentration higher than 250 u&l. Therefore, 600 mg per day seems more efficient to obtain a therapeutic level of itraconazole in ABMT patients but this needs to be conlirmed for all the neutropenic patients.
Canadian Journal of Microbiology, 2001
Sterol composition of four clinical isolates of Aspergillus fumigatus resistant to itraconazole w... more Sterol composition of four clinical isolates of Aspergillus fumigatus resistant to itraconazole was determined by gas chromatography -mass spectrometry and compared with that of four susceptible strains. For all strains, the major sterol was ergosterol. Sterol compositions were qualitatively and quantitatively similar for the resistant and susceptible strains. These results suggest that itraconazole resistance is not related, for the strains studied, to alterations in the ergosterol synthesis pathway.
Canadian Journal of Microbiology, 1999
A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal s... more A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72 h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.
Journal of Biological Chemistry
Neutral glycosphingolipids of the metacestodes of Echinococcus multilocularis, an animal and huma... more Neutral glycosphingolipids of the metacestodes of Echinococcus multilocularis, an animal and human parasite, were resolved by high performance thin layer chromatography into 12 fractions. Nine of these fractions were permethylated, analyzed by electron impact-mass spectrometry, and submitted to methylation analysis by gas chromatography-mass spectrometry. Native fractions were analyzed by liquid secondary ion-mass spectrometry and degraded sequentially by exoglycosidases. In addition to a previously described galactosylceramide, a di-, a tri-, and a tetragalactosyl-ceramide having Gal beta 1-6Gal internal linkages were characterized. This type of carbohydrate chain has been described in glycolipids of a marine mollusk, Turbo cornutus (Matsubara, T., and Hayashi, A. (1981) J. Biochem. (Tokyo), 89, 645-650). In addition two novel fucolipids were found with the following structures: Fuc alpha 1-3Gal beta 1-6Gal-Cer and Gal beta 1-6(Fuc alpha 1-3)Gal beta 1-6Gal-Cer. Ceramides contained...
Comparative Biochemistry and Physiology Part B: Comparative Biochemistry, 1988
l. Lipid distribution of Echinococcus multilocularis was as follows; neutral lipid 48.5%; glycoli... more l. Lipid distribution of Echinococcus multilocularis was as follows; neutral lipid 48.5%; glycolipid 8.4%; and phospholipid 43.0%.
Journal de mycologie médicale, 2013
In the end of May 2012, a meeting of the group "sérodiagnostic fongique" of the "S... more In the end of May 2012, a meeting of the group "sérodiagnostic fongique" of the "Société française de mycologie médicale" had concerned quality controls to use, in particular, in the follow-up of Elisa techniques. A preliminary investigation showed that the internal quality controls (CIQ), according to the terms defined by the accreditation, were not systematically used. In June, was published the new guide of the COFRAC SH-GTA-06 on quality controls, this text being applicable on July 1st, 2012. It incited the working group to formulate proposals on the choice of the CIQ for antigen and antibody Elisa in the aspergillosis serodiagnosis. Informations on the external evaluations of the quality (EEQ) have also been given to better define for what we can expect from it. All these controls will allow every laboratory to better master the used techniques and their conditions of realization. A strengthened dialogue between the users and the manufacturers should incite ...
La Revue du praticien, Jan 30, 2008
Journal of medical microbiology, 2000
The in-vivo activity of amphotericin B and itraconazole against a clinical isolate of Aspergillus... more The in-vivo activity of amphotericin B and itraconazole against a clinical isolate of Aspergillus terreus was determined in a murine model of disseminated aspergillosis. MICs of amphotericin B and itraconazole for the strain, determined by an NCCLS-based technique, were 2 microg/ml and 1 microg/ml, respectively. Mice infected intravenously were treated with either itraconazole (50 or 100 mg/kg/day) or amphotericin B 4.5 mg/kg/day for 10 days. Treatment with both doses of itraconazole significantly prolonged the survival rates compared with those for untreated mice. In comparison, mortality rate and median survival time were identical for mice treated with amphotericin B and for mice given no therapy, indicating that the strain was highly resistant to amphotericin B in this model. Analysis of sterol composition showed that the major sterol was ergosterol. This suggests that amphotericin B resistance was not related to a modified sterol profile.
Biochimica et biophysica acta, Jan 6, 1995
Free ceramides were isolated and purified from the metacestodes of Echinococcus multilocularis. T... more Free ceramides were isolated and purified from the metacestodes of Echinococcus multilocularis. Two different fractions were obtained by preparative thin-layer chromatography. Their structure was determined by gas chromatography and electron impact mass spectrometry of trimethylsilylated derivatives. The ceramide with the higher thin-layer chromatographic migration rate contained exclusively erythro-sphinganine associated with saturated C16, C18 and very-long-chain fatty acids (up to C30) and unsaturated C24 fatty acid. The second ceramide contained 90.3% sphingosine and 9.7% sphinganine associated with saturated C16 and C24 and unsaturated C18 and C24 fatty acids. These findings were discussed with regard to the structure and metabolic pathway of neutral and acid glycosphingolipids found in the metacestodes.
Molecular and Biochemical Parasitology, 1990
Neutral and acid glycosphingolipids of Echinococcus multilocularis metace:,todes that were obtain... more Neutral and acid glycosphingolipids of Echinococcus multilocularis metace:,todes that were obtained after intraperitoneal infection of Meriones unguiculatus have been analyzed by thin layer chromatography. Neutral and acid glycosphingolipids accounted for 95% and 5% of total glycosphingolipids, respectively. 12 different fracticns were observed in the neutral glycosphingolipids extracts of the parasite. The most important was a monohexosylceramide fraction accounting for 56.4% of neutral glycosphingolipids. 9 different fractions were detected in gangliosides (acid glycosphingolipids). The fact that these glycosphingolipids were specific to the parasite was established by the analysis of different cell populations of the host. Glycosphingolipids were purified from control and parasite-infected gerbil blood cells as well as from peritoneal exudate cells of healthy gerbils after a non-specific immunostimulation. The chromatograms obtained with these extracts were totally different from the parasite. In addition, parasitosis was found to have no effect on the host blood cell glycosphingolipids.
Molecular and Biochemical Parasitology, 1990
Monohexosylceramides of Echinococcus multilocularis metacestodes have been isolated and analyzed ... more Monohexosylceramides of Echinococcus multilocularis metacestodes have been isolated and analyzed by thin-layer chromatography, gas-liquid chromatography and mass spectrometry. 90.9% of the parasite fraction was galactosylceramide; glucosylceramide was present at only 9.1%. The most important fatty acids were normal C&.. and C&a fatty acids. The hydroxylated fatty acids of the ceramide part constituted 20.1% of the total, their major constituents were Cur.. and C&a. The sphinganine accounted for 70.4% of long-chain bases, phytosphingosine and sphingosine were also detected. The importance of the long chain fatty acids and the presence of sphinganine in the monohexosylceramide fraction were discussed.
Journal of Medical Microbiology, 1999
An animal model of disseminated aspergillosis was used to test the in-vivo activity of itraconazo... more An animal model of disseminated aspergillosis was used to test the in-vivo activity of itraconazole against four isolates of Aspergillus fumigatus. Two reference isolates of A. fumigatus known to be resistant to itraconazole in vitro and in vivo were used as control isolates, and two new isolates were tested under the same conditions. For each isolate MICs for itraconazole and amphotericin B were determined by an NCCLS-based method. Mice infected intravenously were treated either with itraconazole 100 mg/ kg/day or amphotericin B 4.5 mg/kg/day for 10 days. Amphotericin B showed good invivo activity against all four isolates. For one strain, which had a low in-vitro MIC for itraconazole, in-vivo therapy with itraconazole prolonged the survival of mice and reduced fungal burdens in organs compared with untreated controls. In mice infected with a strain with a high MIC of >16 mg/L, itraconazole neither prolonged survival nor reduced fungal load in organs compared with controls. It is concluded that there is a relationship between MIC and treatment outcome in mice for A. fumigatus infection.
Journal of Antimicrobial Chemotherapy, 2001
The antifungal susceptibility profiles of four ASPERGILLUS: fumigatus isolates, recovered at diff... more The antifungal susceptibility profiles of four ASPERGILLUS: fumigatus isolates, recovered at different times from a patient treated with itraconazole for a pulmonary ASPERGILLUS: infection, were evaluated. Itraconazole MICs against two pre-treatment isolates were 0.5 mg/L, whilst two later isolates, recovered after at least 4 months of itraconazole therapy, had itraconazole MICs of >16 mg/L. In vivo susceptibilities to itraconazole and amphotericin B were tested in a murine model of disseminated aspergillosis. Treatment efficacy was evaluated by examining mortality rates and qualitative cultures of brain and kidneys. Itraconazole therapy significantly prolonged survival of mice infected with the initial isolates as compared with untreated controls. The third isolate was only partially susceptible to itraconazole in vivo, and the fourth isolate was highly resistant. The four isolates were typed by random amplified polymorphic DNA (RAPD) with four different primers. RAPD patterns obtained with each of them were identical, suggesting that the same strain was recovered over time and had acquired resistance to itraconazole.
Journal of Antimicrobial Chemotherapy, 1994
Journal of Antimicrobial Chemotherapy, 2000
Journal of Antimicrobial Chemotherapy, 1999
Abstract The MICs of amphotericin B and itraconazole for 230 isolates of Aspergillus spp., compri... more Abstract The MICs of amphotericin B and itraconazole for 230 isolates of Aspergillus spp., comprising 156 Aspergillus fumigatus, 20 Aspergillus terreus, 22 Aspergillus flavus, 17 Aspergillus nidulans and 15 Aspergillus niger, were determined by a broth microdilution ...
Glycoconjugate Journal, 1993
FEMS Microbiology Letters, 2004
The 14-3-3 protein was shown to be present into the parasitophorous vacuole of Toxoplasma gondii-... more The 14-3-3 protein was shown to be present into the parasitophorous vacuole of Toxoplasma gondii-infected human monocyte cells and in the excreted/secreted antigens (ESA). The ESA 14-3-3 protein migrates electrophoretically as the cytosol and the main membranous 14-3-3 isoforms. The excretion/secretion of 14-3-3 was not sensitive to cycloheximide, a protein synthesis inhibitor, even at a concentration which inhibited the production of 14-3-3 inside the tachyzoites. Recombinant 14-3-3/GST protein was used to test the presence of 14-3-3 antibodies in different human sera. A positive immunoreactivity was observed with sera corresponding to acute toxoplasmosis and a possible involvement of 14-3-3 in host immunity is discussed.
European Journal of Clinical Microbiology & Infectious Diseases, 2005
European Journal of Cancer, 1992
Two different treatments with repeated oral high doses of itraconazole were tested for 10 days in... more Two different treatments with repeated oral high doses of itraconazole were tested for 10 days in 20 neutropenic patients, 10 receiving 400 mg per day and 10 receiving 600 mg per day. In each group 5 patients were treated for acute leukaemia and 5 patients were recipients of autologous bone-marrow transplantation (ABMT). Itraconazole plasma concentrations were assayed by high-performance liquid chromatography. Statistical analysis disclosed a significant interaction between the dispensed dose and the patient types. The difference between the two doses of itraconazole was greater in the ABMT than in the leukaemia patients. After 10 days at 600 mg per day all the ABMT patients had an itraconazole plasma concentration higher than 250 u&l. Therefore, 600 mg per day seems more efficient to obtain a therapeutic level of itraconazole in ABMT patients but this needs to be conlirmed for all the neutropenic patients.
Canadian Journal of Microbiology, 2001
Sterol composition of four clinical isolates of Aspergillus fumigatus resistant to itraconazole w... more Sterol composition of four clinical isolates of Aspergillus fumigatus resistant to itraconazole was determined by gas chromatography -mass spectrometry and compared with that of four susceptible strains. For all strains, the major sterol was ergosterol. Sterol compositions were qualitatively and quantitatively similar for the resistant and susceptible strains. These results suggest that itraconazole resistance is not related, for the strains studied, to alterations in the ergosterol synthesis pathway.
Canadian Journal of Microbiology, 1999
A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal s... more A comparative study of visual and spectrophotometric MIC endpoint determinations for antifungal susceptibility testing of Aspergillus species was performed. A broth microdilution method adapted from the National Committee for Clinical Laboratory Standards (NCCLS) was used for susceptibility testing of 180 clinical isolates of Aspergillus species against amphotericin B and itraconazole. MICs were determined visually and spectrophotometrically at 490 nm after 24, 48, and 72 h of incubation, and MIC pairs were compared. The agreement between the two methods was 99% for amphotericin B and ranged from 95 to 98% for itraconazole. It is concluded that spectrophotometric MIC endpoint determination is a valuable alternative to the visual reference method for susceptibility testing of Aspergillus species.