References of "Hayette, Marie-Pierre"
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See detailApport de la réaction de polymérisation en chaine dans le diagnostic de l'aspergillose invasive
Hayette, Marie-Pierre ULg

Doctoral thesis (2002)

Les aspergilloses invasives surviennent chez les patients immunodéprimés pour la plupart neutropéniques. leur diagnostic est souvent trop tardif et la mise sous traitement aboutit à l'échec dans plus de ... [more ▼]

Les aspergilloses invasives surviennent chez les patients immunodéprimés pour la plupart neutropéniques. leur diagnostic est souvent trop tardif et la mise sous traitement aboutit à l'échec dans plus de 50% des cas. Aussi, il est nécessaire de développer de nouvelles techniques de diagnostic plus sensibles. Dans cette étude deux volets ont été développés: tout d'abord la mise au point d'une technique de polymérisation en chaîne pour la détection d'ADN d'Aspergillus sp. et son utilisation dans les lavages bronchoalvéolaires. Cette étude a montré que la technique développée était sensible et spécifique mais ne permettait pas de distinguer entre infection et colonisation. La seconde étude a consisté en la mise au point d'un modèle expérimental d'aspergillose invasive sur le lapin, dans le but d'évaluer la détection d'ADN fongique par PCR sur sang périphérique, parallèlement à la détection d'antigène galactomannane sérique par ELISA. Les résultats de cette étude ont montré qu'il était possible de détecter de l'ADN fongique dans le sang mais de façon inconstante et souvent postérieurement à la détection d'antigène galactomannane par ELISA. Cela permet de conclure que la place de la PCR Aspergillus sur sang périphérique reste encore à définir dans le diagnositic des aspergilloses invasives. Cependant elle peut être utilisée en complément d'autres techniques diagnostiques. [less ▲]

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See detailSerotype Distribution of clinical isolates of group B streptococci Isolated in Belgium : isolates from neonatal infection compared to isolates from infection in adult or colonization in pregnant women
MELIN, Pierrette ULg; Keke, D.; Campo, B. et al

in American Society of Microbiology (Ed.) Program and Abstracts of the 43rd Intersciences Conference on Antimicrobial Agents and Chemotherapy (2002, September)

Background: Group B Streptococci cause invasive disease in neonates, pregnant women and non-pregnant adults. In the last decades capsular serotypes (type) Ia, Ib, II and III caused the majority of ... [more ▼]

Background: Group B Streptococci cause invasive disease in neonates, pregnant women and non-pregnant adults. In the last decades capsular serotypes (type) Ia, Ib, II and III caused the majority of clinical diseases. More recently, in North America, type V emerged as the more common type in non-pregnant adults with invasive disease. Methods: From January 1999 through December 2001, we received and typed a total of 334 clinically significant strains of GBS isolated in the laboratories belonging to the Belgian network for epidemiological surveillance. 113 were recovered from neonates blood or cerebrospinal fluid (92 early onset EOD, 21 late onset LOD), 14 were isolated from pregnant women with severe infections and 204 were recovered from adults with invasive disease. From the same laboratories, during the first trimester of 2002, 302 isolates from pregnant women were also typed (max. 5 isolates /lab.) Results: In neonatal EOD type III was the more common (41,3%) followed by II (19.6%), Ia (16.3%), Ib (13%), V (8.7%) and IV (1.1%), whereas type III caused the majority (85.7%) of LOD cases. In adults, all types were well represented except type IV: 20.3% Ia, 12.7% Ib, 13.1% II, 23.1% III, 2.7% IV, 19% V and 9% remained non typeable (NT). In colonized pregnant women, all types were also well represented except type IV: 25.5% Ia, 13.3% Ib, 14.9% II, 17.7% III, 5% IV, 15.5% V and 8.1% remained NT. Type III was more frequently the cause of EOD than a colonizing strain during pregnancy and in contrast NT isolates did not cause EOD (P<0.001) Conclusions: 1) Type III was still the major type in neonatal infections in Belgium. 2) Type distribution of GBS differed by age-group of patients 3) Type V belonged to the 3 more represented types in adults 4) Compared to colonizing GBS in pregnant women, distribution of types causing EOD was different. [less ▲]

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See detailIn Vitro Susceptibility Testing of Aspergillus fumigatus against Posaconazole: Comparison of NCCLS M38-P and E-Test Methods
Hayette, Marie-Pierre ULg; Amadore, Agatha; Seidel, Laurence ULg et al

Poster (2002, September)

Posaconazole is a second-generation triazole and structural analogue of itraconazole. This drug has fungicidal activity against yeasts and filamentous fungi. The aim of our study was to evaluate E-test ... [more ▼]

Posaconazole is a second-generation triazole and structural analogue of itraconazole. This drug has fungicidal activity against yeasts and filamentous fungi. The aim of our study was to evaluate E-test method for in vitro susceptibility testing of Aspergillus fumigatus isolates against posaconazole. METHODS: A total of 121 isolates of A. fumigatus were selected as follows: 106 clinical strains from colonized patients, 18 from patients with invasive aspergillosis and 7 environmental isolates. Their in vitro susceptibility was evaluated by E-test (Abbiodisk, Sweden) and compared with NCCLS microdilution reference method (M38-P). Both tests were performed with RPMI 1640 medium at 35 degrees C. MIC values were read after 24h (MIC-24h) and 48h (MIC-48h) incubation time by E-test method. Two MIC endpoints were determined by NCCLS method: 1.no visible reduction of growth (MIC-0); 2. 50% reduction (or more) of growth (MIC-2). Three A. fumigatus reference strains (IHEM 5734, 6149 and 13935) were included as control. RESULTS: Geometric mean MICs (microg/ml) were respectively 0.02 for E-test at 24h and 0.029 at 48h. MIC-0 and MIC-2 values were respectively 0.19 and 0.018 microg/ml. One correlation between both methods was observed for MICs-24h and MICs-2s (p<.05). However, there was no significant difference according to origin of isolates (p<.05). CONCLUSIONS: 1. This study assessed the potent role of posaconazole against A. fumigatus isolates with very low MICs. 2. MIC values were not predictive of pathogenicity. 3. E-test method by reading after 24h-incubation time could easily replace the time-consuming NCCLS M38-P reference method. [less ▲]

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See detailA case of hepatic alveolar echinococcosis contracted in Belgium
Delbecque, Katty ULg; Detry, Olivier ULg; Hayette, Marie-Pierre ULg et al

in Acta Gastro-Enterologica Belgica (2002), 65(1, Jan-Mar), 55-60

We report herein the case of a Belgian 76-year-oId woman who developed a hepatic tumour suspected to be a breast cancer metastasis. Radiological imaging and guided biopsies were not contributive. The ... [more ▼]

We report herein the case of a Belgian 76-year-oId woman who developed a hepatic tumour suspected to be a breast cancer metastasis. Radiological imaging and guided biopsies were not contributive. The patient underwent an explorative laparoscopy with frozen sections that did not provide further diagnosis, and an open left bisegmentectomy was performed during the same anaesthesia. Histopathological examination of the hepatic mass showed Echinococcus multilocularis metacestodes, demonstrating alveolar echinococcosis. As our patient denied any travel in foreign countries and has undergone regular abdominal ultrasonographies since her mastectomy, it is highly likely that this alveolar echinococcosis had been contracted in Belgium. If some imported cases may be seldom managed in Belgium, to our knowledge, this case is the first occurrence of alveolar echinococcosis contracted in Belgium. This report, added to the demonstration of E. multilocaris infection of 50% of red foxes in Southern Belgium, and the potential infection of domestic cats and dogs, should attract attention of the medical community on the possible outbreak of endemic alveolar echinococcosis in Belgium, and on the related public health concerns. [less ▲]

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See detailComparative In Vitro Activity of Amphotericine B, Itraconazole, Voriconazole and Posaconazole against Aspergillus fumigatus
Hayette, Marie-Pierre ULg; Amadore, Agatha; Seidel, Laurence ULg et al

Poster (2001, December)

Background. New azoles have been successfully used as treatment of invasive aspergillosis. The purpose of this study was to compare the in vitro activity of posaconazole (Posa) with that of amphotericin B ... [more ▼]

Background. New azoles have been successfully used as treatment of invasive aspergillosis. The purpose of this study was to compare the in vitro activity of posaconazole (Posa) with that of amphotericin B (AmB), itraconazole (Itra) and voriconazole (Vor) against A. fumigatus isolates according to NCCLS method (M38-P), and to compare visual and spectrophotometric readings for MIC determination. Methods. A total of 106 A. fumigatus isolates were selected as follows: 88 clinical isolates from colonized patients, 18 from patients with invasive aspergillosis and 7 environmental isolates. Their in vitro susceptibility was evaluated by the NCCLS microdilution method (M38-P) in RPMI 1640 medium. Determination of results was made by visual and spectrophotometric readings (630 nm) after 48 hours incubation at 35 degreesC. Three A. fumigatus reference strains (IHEM 5734, 6149 and 13935) were included as control. Results. 1. Geometric mean MICs/MIC90 (microg/ml) obtained by visual reading were respectively 0.66/1 (AmB), 0.37/0.5 (Itra), 0.27/0.5 (Vor) and 0.02/0.03 (Posa). 2. MIC values were comparable by spectrophotometric and by visual readings for all antifungal agents tested (p>.05) and did not depend on the isolates origin (p>.05). 3. Posaconazole had the lowest MICs (p< 0.001). 4. The itraconazole-resistant reference strain did not give cross resistance with voriconazole and posaconazole. CONCLUSIONS: Among azoles, posaconazole had a better in vitro activity against A. fumigatus than did voriconazole or itraconazole. Spectrophotometric reading could replace the less standardized visual reading for NCCLS microdilution method and MIC values obtained were comparable among all A. fumigatus isolates. [less ▲]

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See detailPrevalence of ermB, ermTR and mefA/B gene classes among erythromycine resistant group B streptococcus isolates collected in Belgium
MELIN, Pierrette ULg; Rodriguez Cuns, Grisel; Tsobo, Chantal et al

Poster (2001, October)

Background: Emergence of erythromycin (Er) and clindamycin (C) resistance (R) observed in GBS, is currently becoming recognized. Methods: Clinical isolates were obtained from a Belgian surveillance for ... [more ▼]

Background: Emergence of erythromycin (Er) and clindamycin (C) resistance (R) observed in GBS, is currently becoming recognized. Methods: Clinical isolates were obtained from a Belgian surveillance for invasive GBS disease in newborns and adults in 1996-1998 (N1=235) and from consecutive specimens submitted, during 1999-2000, to the University hospital of Liege (N2=165). MICs of Er were determined buy using Etest® strip (interpretive criteria of NCCLS). Furthermore, for the ErR isolates, the inducible (iMLS), constitutive (cMLS) and M phenotypes were assessed by disk diffusion and by a double-disk test; the distribution of genes encoding RNA methylases and efflux pumps was investigated by PCR. Results: Of the N1 and N2 isolates, 16 (6.8%) and 19 (11.5%) were respectively R to Er. Among these 35 ErR isolates, 21 (60%) exhibited the cMLS phenotype. They demonstrated a high level R to Er with MICs ranging from 16 to >256 mg/L. The ermB gene was harbored by 19/21 isolates, the ermTR gene by 1 isolate and both ermB and ermTR were present in another isolate. The iMLS phenotype was observed in 10 (29%) ErR isolates; the ermTR gene was present in all isolates except one harboring an ermTR gene. These strains demonstrated low level of R to Er, with MICs of 1-12 mg/L. All 4 isolates (11%) expressing an M phenotype, displayed low level R to Er alone (MICs, 2 mg/L) and were positive for the mefA/B gene. Conclusion: In Belgium, by year 2000, prevalence of R to macrolide in GBS exceeded 10%. R was mainly caused by target-site modification (ermB, ermTR) mechanisms; efflux (mefA/B) R mechanism was also prevalent among the isolates tested. These results indicate the possibility of inappropriate prophylaxis or therapy using C or E as the recommended alternatives in penicillin-allergic patients. [less ▲]

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See detailReversal of Chloroquine and Mefloquine Resistance in Plasmodium Falciparum by the Two Monoindole Alkaloids, Icajine and Isoretuline
Frederich, Michel ULg; Hayette, Marie-Pierre ULg; Tits, Monique ULg et al

in Planta Medica (2001), 67(6), 523-7

Eight naturally occurring monoindole alkaloids were evaluated in vitro for their ability to inhibit Plasmodium falciparum growth and, in drug combination, to reverse the resistance of a chloroquine ... [more ▼]

Eight naturally occurring monoindole alkaloids were evaluated in vitro for their ability to inhibit Plasmodium falciparum growth and, in drug combination, to reverse the resistance of a chloroquine-resistant strain of Plasmodium falciparum. None of these indole alkaloids has significant intrinsic antiplasmodial activity (IC(50) > 10 microM or 5 microg/ml). Nevertheless, three alkaloids (icajine, isoretuline and strychnobrasiline) did reverse chloroquine resistance at concentrations between 2.5 and 25 microg/ml (IF of 12.82 for isoretuline on W2 strain). The Interaction Factor (IF) equals 2, < 2, or > 2 for additive, antagonistic or synergistic effects of alkaloids on chloroquine inhibition, respectively. Icajine and isoretuline were also assessed in vitro for their mefloquine potentiating activity on a mefloquine-resistant strain of Plasmodium falciparum. Only icajine proved to be synergistic with mefloquine (IF = 15.38). [less ▲]

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See detailIn Vitro Comparison of the Antimycotic Activity of a Miconazole-Hp-Beta-Cyclodextrin Solution with a Miconazole Surfactant Solution
Piel, Géraldine ULg; Hayette, Marie-Pierre ULg; Pavoni, Ermanno et al

in Journal of Antimicrobial Chemotherapy (2001), 48(1), 83-7

The antimycotic activity of a new parenteral solution containing miconazole was compared with that of a marketed solution (Daktarin IV solution). This solution has been withdrawn from the Belgian market ... [more ▼]

The antimycotic activity of a new parenteral solution containing miconazole was compared with that of a marketed solution (Daktarin IV solution). This solution has been withdrawn from the Belgian market, probably because of toxic effects related to the presence of polyoxyl 35 castor oil. We propose a new formulation containing miconazole (10 mg/mL) (like the marketed solution), in combination with hydroxypropyl-beta-cyclodextrin and lactic acid. The MICs of these two solutions were determined by a broth microdilution method (based on NCCLS guidelines) for 67 yeasts and 50 filamentous fungi isolates. This study shows that the MICs obtained with these two solutions are not significantly different. [less ▲]

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See detailDetection of Aspergillus spp. by PCR in Bronchoalveolar Lavage Fluid
Hayette, Marie-Pierre ULg; Vaira, Dolorès ULg; Suzin, Fabrice et al

in Journal of Clinical Microbiology (2001), 39(6), 2338-2340

The usefulness of a nested PCR assay for detection of Aspergillus sp. DNA was evaluated in 177 bronchoalveolar lavage (BAL) fluid specimens. This test was accurate both to diagnose culture-negative BAL ... [more ▼]

The usefulness of a nested PCR assay for detection of Aspergillus sp. DNA was evaluated in 177 bronchoalveolar lavage (BAL) fluid specimens. This test was accurate both to diagnose culture-negative BAL fluid specimens from patients with invasive pulmonary aspergillosis and to confirm culture-positive samples. However, it did not differentiate between infection and colonization. [less ▲]

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See detailStrychnogucines a and B, Two New Antiplasmodial Bisindole Alkaloids from Strychnos Icaja
Frederich, Michel ULg; Gillet, Marie-Claire ULg; Prosperi, Christelle ULg et al

in Journal of Natural Products (2001), 64(1), 12-16

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by ... [more ▼]

A reinvestigation of Strychnos icaja roots has resulted in the isolation of two tertiary quasi-symmetric bisindole alkaloids named strychnogucines A (1) and B (2). Their structures were identified by means of spectroscopic data interpretation. Compound 2 was highly active in vitro and compound 1 moderately active against four strains of Plasmodium falciparum. Strychnogucine B (2) was more active against a chloroquine-resistant strain than against a chloroquine-sensitive one (best CI(50), 80 nM against the W2 strain). In addition, this compound showed a selective antiplasmodial activity with 25-180 times greater toxicity toward P. falciparum, relative to cultured human cancer cells (KB) or human fibroblasts (WI38). [less ▲]

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See detailPrevention of neonatal group B streptococcal disease in Belgium: hospital policy, obstetricians' practice and laboratory processing
MELIN, Pierrette ULg; Schmitz, Myriam; Heinrichs, I. et al

Poster (2000, November 25)

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See detailPrevention of neonatal group B streptococcal disease in Belgium: hospital policy, obstetricians' practice and laboratory processing
MELIN, Pierrette ULg; Schmitz, Myriam; Heinrichs, I. et al

in American Society of Microbiology (Ed.) Program and Abstracts of the 40th Intersciences Conference on Antimicrobial Agents and Chemotherapy (2000, September)

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See detailStrychnogucines A and B, two new antiplasmodial bisindole alkaloids from Strychnos icaja
Frederich, Michel ULg; Tits, Monique ULg; Penelle, Jacques et al

Poster (2000, September)

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See detailRapid intrapartum test (Strep B OIA) and prenatal cultures for identification of group B streptococcal carriers at delivery: a prospective study
MELIN, Pierrette ULg; Schmitz, Myriam; Tsobo, Chantal et al

in AAmerican Society of Microbiology (Ed.) Program and Abstracts of the 40th Intersciences Conference on Antimicrobial Agents and Chemotherapy (2000, September)

Background: The efficacy of the prenatal screening-based approach recommended by the CDC to prevent neonatal GBS diseases could be improved by using a good rapid test performed at the onset of labor. To ... [more ▼]

Background: The efficacy of the prenatal screening-based approach recommended by the CDC to prevent neonatal GBS diseases could be improved by using a good rapid test performed at the onset of labor. To assess the Strep B OIA® test (Biostar, Boulder, Co), completed in 30 minutes, we initiated a 6-center study to compare it with prenatal screening cultures to identify GBS carriers at delivery or opportunities to initiate intrapartum antibioprophylaxis (IAP). Methods: For a total of 539 pregnant women included in the study, pairs of vaginal/anal specimens collected at 35-37 weeks and intrapartum vaginal specimens were plated onto colistin-nalidixic agar and then inoculated into selective LIM broth for the detection of GBS. Furthermore, on each intrapartum vaginal swab a Strep B OIA test was performed. Results: GBS were recovered in culture from 89 prenatal screenings (17%) and from 71 specimens collected at delivery (13%). Strep B OIA test identified 48 positive specimens (9%). Respectively, for the identification of GBS carriers at delivery, sensitivity, specificity, positive and negative predictive values for prenatal screening cultures were 69%, 91%, 55% and 95% and for Strep B OIA tests they were 63%, 99%, 94% and 95%. Evaluating opportunities to start an IAP, based on Strep OIA test versus prenatal screening cultures, 45 IAP vs. 49 would have been useful, 3 vs. 40 useless (P< 0,001) and 26 vs. 22 missed. Conclusion: To identify GBS carriers, the Strep B OIA test, performed at the time of onset of labor is equally sensitive to prenatal screening cultures and would allow a highly significant reduction of useless IAP. [less ▲]

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See detailNew Antimalarial and Cytotoxic Sungucine Derivatives from Strychnos Icaja Roots
Frederich, Michel ULg; Gillet, Marie-Claire ULg; Llabres, Gabriel ULg et al

in Planta Medica (2000), 66(3), 262-9

Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy ... [more ▼]

Reinvestigation of Strychnos icaja Baillon resulted in the isolation of vomicine, isostrychnine and of three new sungucine derivatives, named isosungucine (8), 18-hydroxy-sungucine (9) and 18-hydroxy-isosungucine (10). They were identified by detailed spectroscopic methods. The complete 1H- and 13C-NMR study of sungucine was also realized. Some of these compounds were highly active against Plasmodium falciparum in vitro and more particularly against the chloroquine-resistant strain. Compound 10 showed a selective antiplasmodial activity, with > 100-fold greater toxicity towards Plasmodium falciparum, relative to cultured human cancer cells (KB and HeLa lines) or fibroblasts (WI38). [less ▲]

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