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See detailImaging gliomas with positron emission tomography and single-photon emission computed tomography
Bénard, François; Romsa, Jonathan; Hustinx, Roland ULiege

in Seminars in Nuclear Medicine (2003), 33(2), 148-162

Over the last two decades the large volume of research involving various brain tracers has shed invaluable light on the pathophysiology of cerebral neoplasms. Yet the question remains as to how best to ... [more ▼]

Over the last two decades the large volume of research involving various brain tracers has shed invaluable light on the pathophysiology of cerebral neoplasms. Yet the question remains as to how best to incorporate this newly acquired insight into the clinical context. Thallium is the most studied radiotracer with the longest track record. Many, but not all studies, show a relationship between Tl-201 uptake and tumor grade. Due to the overlap between tumor uptake and histologic grades, Tl-201 cannot be used as the sole noninvasive diagnostic or prognostic tool in brain tumor patients. However, it may help differentiating a high-grade tumor recurrence from radiation necrosis. MIBI is theoretically a better imaging agent than Tl-201 but it has not convincingly been shown to differentiate tumors according to grade. MDR-1 gene expression as demonstrated by MIBI does not correlate with chemoresistance in high grade gliomas. Currently, MIBI's clinical role in brain tumor imaging has yet to be defined. IMT, a radio-labeled amino acid analog, may be useful for identifying postoperative tumor recurrence and, in this application, appears to be a cheaper, more widely available tool than positron emission tomography (PET). However, its ability to accurately identify tumor grade is limited. 18 F-2-Fluoro-2-deoxy-D-glucose (FDG) PET predicts tumor grade, and the metabolic activity of brain tumors has a prognostic significance. Whether FDG uptake has an independent prognostic value above that of histology remains debated. FDG-PET is effective in differentiating recurrent tumor from radiation necrosis for high-grade tumors, but has limited value in defining the extent of tumor involvement and recurrence of low-grade lesions. Amino-acid tracers, such as MET, perform better for this purpose and thus play a complementary role to FDG. Given the poor prognosis of patients with gliomas, particularly with high-grade lesions, the overall clinical utility of single photon emission computed tomography (SPECT) and PET in characterizing recurrent lesions remains dependent on the availability of effective treatments. These tools are thus mostly suited to the evaluation of treatment response in experimental protocols designed to improve the patients' outcome. (C) 2003 Elsevier Inc. All rights reserved. [less ▲]

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See detailInheritance of sex in two ZZ pseudofemale lines of tilapia Oreochromis aureus
Desprez, D.; Mélard, Charles ULiege; Hoareau, M. C. et al

in Aquaculture (2003), 218(1-4), 131-140

This paper reports a study on the sex determination system of the blue tilapia, Oreochromis aureus. Investigations were carried out using a pseudofemale line in two populations of O. aureus, known as ... [more ▼]

This paper reports a study on the sex determination system of the blue tilapia, Oreochromis aureus. Investigations were carried out using a pseudofemale line in two populations of O. aureus, known as Egyptian Population (EP) and Israel Population (IP). In O. aureus, males are the homogametic sex (ZZ/ZW), and sex reversal of fry with estradiol results in the production of some functional sex-reversed fish with a female phenotype and ZZ male genotype, known as pseudofemales or A-females. Crosses between ZZ pseudofemales and ZZ males theoretically should provide monosex ZZ male progeny only. We have studied the sex ratios of progeny from 43 IP (F-2 to F-3 generations) and 51 EP (F-1 to F-5 generations), pair-matings between normal males and pseudofemales. In IP, the male percentage in progenies ranged between 83% to 100% in F-2 and 66% to 100% in F-3. In EP, male percentage was more constant, varying from 88% to 100% in F-1, from 96% to 100% in F-3 and from 97% to 100% in F-5. In EP, F-2 and F-4 pseudofemales produced only monosex male progeny. This apparent difference in sex ratio frequency distributions between the two O. aureus pseudofemale lines could be due to the selection of males. EP pseudofemales were mated with their siblings for F-2 and F-3 pseudofemales or with closely related males for F-4 and F-5 pseudofemales. Conversely, IP pseudofemales were crossed with nonrelated males originating from research center broodstock, resulting in a higher proportion of females in sex ratio of progenies from successive generations of pseudofemales. The role of inbreeding is discussed in the context of predominantly monofactorial sex chromosome determination system operating in this species, influenced by other factors (genetic and environmental). The present study also shows that it is possible to fix the male sex determining factors (Z sex chromosome and genetic factors) in a line of pseudofemales, producing a high percentage of male progeny in five successive generations. (C) 2003 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailCatalytic mechanism of the Streptomyces K15 DD-transpeptidase/penicillin-binding protein probed by site-directed mutagenesis and structural analysis
Rhazi, Noureddine ULiege; Charlier, Paulette ULiege; Dehareng, Dominique ULiege et al

in Biochemistry (2003), 42(10), 2895-2906

The Streptomyces K15 penicillin-binding DD-transpeptidase is presumed to be involved in peptide cross-linking during bacterial cell wall peptidoglycan assembly. To gain insight into the catalytic ... [more ▼]

The Streptomyces K15 penicillin-binding DD-transpeptidase is presumed to be involved in peptide cross-linking during bacterial cell wall peptidoglycan assembly. To gain insight into the catalytic mechanism, the roles of residues Lys38, Ser96, and Cys98, belonging to the structural elements defining the active site cleft, have been investigated by site-directed mutagenesis, biochemical studies, and X-ray diffraction analysis. The Lys38His and Ser96Ala mutations almost completely abolished the penicillin binding and severely impaired the transpeptidase activities while the geometry of the active site was essentially the same as in the wild-type enzyme. It is proposed that Lys38 acts as the catalytic base that abstracts a proton from the active serine Ser35 during nucleophilic attack and that Ser96 is a key intermediate in the proton transfer from the Ogamma of Ser35 to the substrate leaving group nitrogen. The role of these two residues should be conserved among penicillin-binding proteins containing the Ser-Xaa-Asn/Cys sequence in motif 2. Conversion of Cys98 into Asn decreased the transpeptidase activity and increased hydrolysis of the thiolester substrate and the acylation rate with most beta-lactam antibiotics. Cys98 is proposed to play the same role as Asn in motif 2 of other penicilloyl serine transferases in properly positioning the substrate for the catalytic process. [less ▲]

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See detailActivity-stability relationships in extremophilic enzymes
D'Amico, Salvino ULiege; Marx, J. C.; Gerday, Charles ULiege et al

in Journal of Biological Chemistry (2003), 278(10), 7891-7896

Psychrophilic, mesophilic, and thermophilic alpha-amylases have been studied as regards their conformational stability, heat inactivation, irreversible unfolding, activation parameters of the reaction ... [more ▼]

Psychrophilic, mesophilic, and thermophilic alpha-amylases have been studied as regards their conformational stability, heat inactivation, irreversible unfolding, activation parameters of the reaction, properties of the enzyme in complex with a transition state analog, and structural permeability. These data allowed us to propose an energy landscape for a family of extremophilic enzymes based on the folding funnel model, integrating the main differences in conformational energy, cooperativity of protein unfolding, and temperature dependence of the activity. In particular, the shape of the funnel bottom, which depicts the stability of the native state ensemble, also accounts for the thermodynamic parameters of activation that characterize these extremophilic enzymes, therefore providing a rational basis for stability-activity relationships in protein adaptation to extreme temperatures. [less ▲]

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See detailIMAGE FUV and in situ FAST particle observations of substorm aurorae
Mende, S. B.; Carlson, C. W.; Frey, H. U. et al

in Journal of Geophysical Research. Space Physics (2003), 108

Images from the IMAGE Wide-band Imaging Camera (WIC) and Spectrographic Imager (SI) channels SI-12 and SI-13 were compared to in situ data taken by FAST during several substorms. FAST spacecraft ... [more ▼]

Images from the IMAGE Wide-band Imaging Camera (WIC) and Spectrographic Imager (SI) channels SI-12 and SI-13 were compared to in situ data taken by FAST during several substorms. FAST spacecraft observations have shown that the high latitude auroral ionosphere has several distinct regions. Intense auroras are seen in regions of upward directed quasi static electric fields and of Alfven wave accelerated superthermal electrons. In two of the cases presented, the satellite passed through an active poleward propagating substorm surge on its duskward flank. Both show that the superthermal wave accelerated component to be on the polar cap boundary of the surge, and that it could be distinguished from quasi static field ``inverted V'' precipitation which occurred at the more equatorward parts of the auroral oval. In one of these cases, the surge was accompanied by intense ion outflow. Three cases showed the FAST satellite passing through the substorm aurora at midnight or the dawn side outside of the surge and the wave accelerated electrons were less clearly separated from the inverted V type precipitation. The wave accelerated electrons were seen to be part of very short-lived transient events, i.e., bursts. The region of auroral forms, associated with Alfven waves exhibit relatively soft auroral precipitation with very intense electron fluxes. By comparing the intensity of the WIC and SI-13 channels of IMAGE FUV, it is possible sometimes to distinguish optically between the two types of regions. Global imaging of the two regions would allow the separation of quasi-static plasma convection regions containing inverted V-s from regions of Alfven wave driven electrons signifying substorm related magnetic field dynamics. [less ▲]

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See detailLarge-scale Wind Structures in OB Supergiants: a Search for Rotationally Modulated Halpha variability
Morel, Thierry ULiege; Marchenko, S. V.; Pati, A. K. et al

in Bulletin of the Astronomical Society of India (2003), 31

We present preliminary results of a long-term spectroscopic monitoring of a sample of bright OB-supergiants aimed at establishing the incidence of co-rotating, large-scale wind structures by detecting ... [more ▼]

We present preliminary results of a long-term spectroscopic monitoring of a sample of bright OB-supergiants aimed at establishing the incidence of co-rotating, large-scale wind structures by detecting rotationally modulated variability in H. Dramatic line-profile variations operating on a daily (and in some cases on a hourly) timescale are observed. A detailed period analysis has been so far carried out for 2 stars, and revealed in both cases the existence of cyclical H variations consistent with rotational modulation. In the case of HD 14134, the same periodicity is found in the contemporaneous light curve. [less ▲]

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See detailA psycho-endocrinological overview of transsexualism
Michel, Aude; Mormont, Christian ULiege; Legros, Jean-Jacques ULiege

in European Journal of Endocrinology (2003), 148(3), 375-375

The technical possibility of surgical sex change has opened up a debate concerning the legitimacy and utility of carrying out such an intervention at the request of the transsexual. Diagnostic ... [more ▼]

The technical possibility of surgical sex change has opened up a debate concerning the legitimacy and utility of carrying out such an intervention at the request of the transsexual. Diagnostic, psychological, medical and ethical arguments have been brought forth, both for and against. Nonetheless, anatomical transformation by surgical means has currently become a practice as the frequency of serious gender identity disorders is constantly progressing. After a brief introduction, the present paper will consider typological, aetiological and epidemiological aspects of transsexualism. Treatment of the sex change applicant is then defined and discussed in terms of psychological, psychiatric, endocrinological and surgical aspects. Finally, the question of post-operation follow-up will be examined. [less ▲]

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See detailSensation-seeking and impulsivity in young and older adults' decision making
Willems, Sylvie ULiege; Van der Linden, Martial ULiege; Marczewski, Philippe

in Brain & Cognition (2003), 51(2), 237-239

The somatic marker hypothesis asserts that decision-making processes involve emotion. Using a gambling task that models real-life decisions, studies showed that old adults perform less efficiently than ... [more ▼]

The somatic marker hypothesis asserts that decision-making processes involve emotion. Using a gambling task that models real-life decisions, studies showed that old adults perform less efficiently than younger adults, by adopting a strategy that is disadvantageous on the long term. This study aimed at re-examining the age effect on decisionmaking with the same paradigm, and to explore whether differences are related to sensation-seeking and impulsivity traits of personality. Young and older adults were compared on the gambling task (Bechara, Damasio, & Damasio, 2000a), and on questionnaires of sensationseeking and impulsivity. Results confirmed an age effect on the gambling task performance. Moreover, performance in both young and older adults on this task was correlated to scores on the sensation-seeking scale, but not to the rating of impulsivity [less ▲]

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See detailOccurrence and characteristics of CS31A antigen-producing Escherichia coli in calves with diarrhoea and septicaemia in Argentina.
Mercado, E. C.; Rodriguez, Sabrina ULiege; D'Antuono, A. L. et al

in Journal of Veterinary Medicine. B, Infectious Diseases & Veterinary Public Health (2003), 50(1), 8-13

CS31A is a K88-related non-fimbrial adhesin first described on Escherichia coli strains isolated from diarrhoeic and septicaemic calves. In this report, CS31A antigen was screened by immunological methods ... [more ▼]

CS31A is a K88-related non-fimbrial adhesin first described on Escherichia coli strains isolated from diarrhoeic and septicaemic calves. In this report, CS31A antigen was screened by immunological methods and confirmed by PCR among bovine E. coli isolates. In addition, CS31A-producing strains were characterized with respect to different fimbrial antigens, O-serogroup and other properties related to virulence. Faecal or tissue specimens of 100 diarrhoeic or septicaemic calves and 27 older cattle with different pathologies from 71 outbreaks or individual cases that occurred in Buenos Aires province, Argentina, were examined. CS31A + E. coli strains were isolated from 21 (21.0%) calves from 16 outbreaks or individual cases. No CS31A + E. coli was detected in samples from cattle more than 1 year old. Fimbriae F5, F41, F17a and F17b were not detected among the CS31A-producing strains. Three (14.3%) of the CS31A+ E. coli strains expressed the F17c fimbria. All of the 21 isolates exhibited at least one property of septicaemic strains (resistance to serum, production of aerobactin or colicins) but none of them demonstrated heat-stable enterotoxigenic activity. CS31A + E. coli isolates belonged to 10 serogroups, more commonly O8, O7, O17 and O21. The results obtained here confirm the worldwide distribution of CS31A antigen in bovine E. coli strains. However, CS31A + or CS31A + /F17c + E. coli were less frequently isolated than they were in North hemisphere countries. [less ▲]

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See detailRole of plasminogen activator-plasmin system in tumor angiogenesis
Rakic, Jean-Marie ULiege; Maillard, Catherine ULiege; Jost, M. et al

in Cellular and Molecular Life Sciences : CMLS (2003), 60(3), 463-473

New blood formation or angiogenesis has become a key target in therapeutic strategies aimed at inhibiting tumor growth and other diseases associated with neovascularization. Angiogenesis is associated ... [more ▼]

New blood formation or angiogenesis has become a key target in therapeutic strategies aimed at inhibiting tumor growth and other diseases associated with neovascularization. Angiogenesis is associated with important extracellular remodeling involving different proteolytic systems among which the plasminogen system plays an essential role. It belongs to the large serine proteinase family and can act directly or indirectly by activating matrix metalloproteinases or by liberating growth factors and cytokines sequestered within the extracellular matrix. Migration of endothelial cells is associated with significant upregulation of proteolysis and, conversely, immunoneutralization or chemical inhibition of the system reduces angiogenesis in vitro. On the other hand, genetically altered mice developed normally without overt vascular anomalies indicating the possibility of compensation by other proteases in vivo. Nevertheless, they have in some experimental settings revealed unanticipated roles for previously characterized proteinases or their inhibitors. In this review, the complex mechanisms of action of the serine proteases in pathological angiogenesis are summarized alongside possible therapeutic applications. [less ▲]

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See detailMutations in the ganglioside-induced differentiation-associated protein-1 (GDAP1) gene in intermediate type autosomal recessive Charcot-Marie-Tooth neuropathy
Senderek, J.; Bergmann, C.; RAMAEKERS, Vincent ULiege et al

in Brain (2003), 126(3), 642-649

Mutations in the gene for the ganglioside-induced differentiation-associated protein-1 (GDAP1) on 8q21 recently were reported to cause autosomal recessive Charcot-Marie-Tooth (CMT) sensorimotor neuropathy ... [more ▼]

Mutations in the gene for the ganglioside-induced differentiation-associated protein-1 (GDAP1) on 8q21 recently were reported to cause autosomal recessive Charcot-Marie-Tooth (CMT) sensorimotor neuropathy. Neurophysiology and nerve pathology were heterogeneous in these cases: a subset of GDAP1 mutations was associated with peripheral nerve demyelination, whereas others resulted in axonal degeneration. In this study, we identified two novel mutations disrupting the GDAP1 reading frame. Homozygosity for a single base pair insertion in exon 3 (c.349_350insT) was observed in affected children from a Turkish inbred pedigree. The other novel allele detected in a German patient was a homozygous mutation of the intron 4 donor splice site (c.579 + 1G>A). Patients with GDAP1 mutations displayed severe, early childhood-onset CMT neuropathy with prominent pes equinovarus deformity and impairment of hand muscles. Nerve conduction velocities were between 25 and 35 m/s and peripheral nerve pathology showed axonal as well as demyelinating changes. These findings fitted the definition of intermediate type CMT and further support the view that GDAP1 is vital for both, axonal integrity and Schwann cell properties. [less ▲]

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See detailInhaled corticosteroids effects on bone in asthmatic and COPD patients: a quantitative systematic review
Richy, Florent; Bousquet, Jean; Ehrlich, George E et al

in Osteoporosis International (2003), 14(3), 179-190

Deleterious effect of oral corticosteroids on bone has been well documented, whereas this remains debated for inhaled ones (ICS). Our objectives were to analyze the effects of ICS on bone mineral density ... [more ▼]

Deleterious effect of oral corticosteroids on bone has been well documented, whereas this remains debated for inhaled ones (ICS). Our objectives were to analyze the effects of ICS on bone mineral density, fracture risk and bone markers. We performed an exhaustive systematic research of all controlled trials potentially containing pertinent data, peer-reviewed by a dedicated WHO expert group, and comprehensive meta-analyses of the data. Inclusion criteria were ICS, and BMD/markers/fractures in asthma/chronic obstructive pulmonary diseases (COPD) and healthy patients. Analyses were performed in a conservative fashion using professional dedicated softwares and stratified by outcome, study design and ICS type. Results were expressed as standardized mean difference/effect size (ES), relative risk (RR) or odds ratio (OR), depending on study design and outcome units. Publication bias was investigated. Twenty-three trials were reviewed; 11 papers fit the inclusion criteria and were assessed for the main analysis. Quality scores for the randomized controlled trials (RCTs) were 80%, 71% for the prospective cohort studies, and 78% for the retrospective cohort and cross-sectional studies. We globally assessed ICS effects on BMD and found deleterious effects: ES=0.61 (p=0.001) for healthy subjects, and ES=0.27 (p<0.001) for asthma/COPD patients. For these patients, this effect was 0.21 (p<0.01) at the lumbar spine, and 0.26 (p<0.001) at the hip or femoral neck. A single study evaluated the impact of ICS on hip fracture and reported an increased OR of 1.6 (1.24; 2.03). Lumbar fracture rate differences did not reach the level of statistical significance: 1.87 (0.5; 6.94). Osteocalcin and PICP were decreased and ICTP, pyridinoline and deoxypyridinoline levels were not significantly affected. Budesonide (BUD) appeared to be the ICS inducing the less deleterious effects on bone, followed by beclomethasone dipropionate (BDP) and triamcinolone (TRI). Publication bias investigation provided non-significant results. In our meta-analyses, BUD at a mean daily dose (SD) of 686 mug (158 mug), BDP at 703 mug (123 mug) and TRI at 1000 mug (282 mug) were found to affect bone mineral density and markers in patients suffering from the two major respiratory diseases. These findings could have practical implication in the long-term management of asthmatic and COPD patients. [less ▲]

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See detailInflammatory pseudotumors of the central nervous system: Report of 3 cases and a literature review
Häusler, M.; Schaade, L.; Ramaekers, Vincent ULiege et al

in Human Pathology (2003), 34(3), 253-262

Inflammatory pseudotumors (IPs), mostly benign lesions characterized by fibrotic ground tissue and polyclonal mononuclear infiltrate, may affect all organ systems. IPs originating in the central nervous ... [more ▼]

Inflammatory pseudotumors (IPs), mostly benign lesions characterized by fibrotic ground tissue and polyclonal mononuclear infiltrate, may affect all organ systems. IPs originating in the central nervous system (IP-CNS) are very rare, and their distinct histopathologic features are poorly characterized. Three otherwise healthy patients (age 8, 15, and 17 years) presented with focal neurologic symptoms (seizures, n = 2; headaches, n = 1), corresponding to a left temporal, left occipital, and left frontal IP, respectively, extending from meningeal structures into brain tissue. After resection, no recurrence was observed in patient 1 during 5 years of follow-up, whereas patient 2 developed a rapidly progressive local recurrence and a second intracerebral lesion despite antiviral, immunosuppressive, antibiotic, and radiation therapy. In patient 3, who also showed local recurrences, sequential histopathologic investigations revealed transformation to a semimalignant fibrohistiocytic tumor. In this patient, anaplastic lymphoma kinase (ALK) expression was also positive, whereas it was negative in patient 1. A detailed literature analysis confirmed that most IP-CNS arise from dural/meningeal structures (n = 34). Intraparenchymatous (n = 7), mixed intraparenchymatous/meningeal (n = 4), and intraventricular lesions (n = 7) or IP extending per continuitatem from intracerebral to extracerebral sites (n = 5) were rare. The recurrence rate was 40% within 2 years in general. It was increased after incomplete resection and in female patients (multivariate Cox regression model, P < 0.02). Although rare, IP-CNS are important differential diagnoses among tumor-like intracranial lesions. Their potential risk of malignant transformation and high risk of recurrence necessitate close follow-up, especially when resection is incomplete. Prospective multicenter trials are needed to optimize classification and treatment of this rare inflammatory lesion. Copyright 2003, Elsevier Inc. All rights reserved. [less ▲]

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See detailAdherence of Mycoplasma bovis to bovine bronchial epithelial cells
Thomas, Anne; Sachse, K.; Farnir, Frédéric ULiege et al

in Microbial Pathogenesis (2003), 34(3), 141-148

Mycoplasma bovis is responsible for considerable economic losses in cattle due to pneumonia, arthritis and mastitis. As the agent was shown to be capable of adhering to neutrophils and embryonic bovine ... [more ▼]

Mycoplasma bovis is responsible for considerable economic losses in cattle due to pneumonia, arthritis and mastitis. As the agent was shown to be capable of adhering to neutrophils and embryonic bovine lung (EBL) cells and invading the respiratory epithelium it is highly desirable to improve our understanding of cytadherence processes. Although several surface proteins likely to be directly involved in this initial stage of interaction between pathogen and host cells have been identified, these findings mainly referred to type strain PG45 adhering to the continuous EBL cell line. The present study provides new and complementary data about cytadherence of M. bovis based on adherence of various radiolabeled strains to a primary culture of bovine bronchial epithelial (BBE) cells using a standardized adherence assay. M. bovis was shown to adhere specifically to the primary culture of BBE cells. Inhibition of adherence was observed upon addition of monoclonal antibodies (MAbs), trypsin treatment of mycoplasmas, and competition with non-radiolabeled mycoplasma cells. Interestingly, three MAbs against proteins involved in adherence to EBL cells failed to inhibit significantly the adherence to BBE cells. On the other hand, significant reduction of adherence rates by MAbs 2A8 and 9F1 directed against epitopes of variable surface lipoproteins VspC and VspF, respectively, demonstrated the involvement of these proteins in adherence of M. bovis to primary culture of BBE cells. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailMexiko: (De-)Konstruktion von Nation und Ethnie im Diskurs der Guerilla
Vanden Berghe, Kristine ULiege; Maddens, Bart

in WeltTrends : Zeitschrift für internationale Politik und vergleichende Studien. (2003), 38

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See detailGalectin-1 accumulation in the ovary carcinoma peritumoral stroma is induced by ovary carcinoma cells and affects both cancer cell proliferation and adhesion to laminin-1 and fibronectin
van den Brule, Frédéric; Califice, Stéphane; Garnier, Frédérique et al

in Laboratory Investigation : Journal of Technical Methods & Pathology (2003), 83(3), 377-386

Galectin-1 (gal-1) is a 14-kDa laminin-binding galectin involved in several biologic events including regulation of cancer cell proliferation and adhesion to the matrix. In this study, we examined gal-1 ... [more ▼]

Galectin-1 (gal-1) is a 14-kDa laminin-binding galectin involved in several biologic events including regulation of cancer cell proliferation and adhesion to the matrix. In this study, we examined gal-1 expression in 30 human epithelial ovary carcinoma samples by Western and Northern blotting and by immunohistochemistry. Gal-1 mRNA levels were increased in more than 95% of the examined ovary carcinoma samples, compared with a wedge resection of a normal ovary. Immunohistochemical analysis of the samples demonstrated gal-1 expression in cancer epithelial cells from 17 of 30 samples, with a cytoplasmic pattern. Gal-1 immunostaining was significantly increased in the stroma associated with carcinoma cells compared with the normal, noninvaded stroma (p = 0.003). This pattern of expression was confirmed by examination of 12 other frozen epithelial ovary carcinomas, using in situ hybridization. Immunohistochemical staining of the specimens demonstrated colocalization of gal-1, laminin-1, and fibronectin. In vitro experiments were conducted to elucidate the potential biologic role of gal-1 in ovarian cancer progression. Gal-1 protein expression and release was detected in AZ364, SK-OV-3, and AZ224, but not in OVCAR-3, AZ419, and AZ382, human ovary carcinoma cell lines. Incubation of 84BR fibroblasts with conditioned media harvested from the ovary carcinoma cell lines induced an increased expression of gal-1 in the cultured fibroblasts in all cases except AZ419 and SK-OV-3. High concentrations of gal-1 (100 mug/ml) induced significantly decreased cell proliferation in all cell lines, as defined by bromodeoxyuridine incorporation. Additionally, recombinant gal-1 induced a dose-dependent increase in in vitro adhesion of AZ224, SK-OV-3, and AZ382 cells to laminin-1; adhesion to fibronectin was increased by gal-1 in OVCAR-3, AZ224, and SK-OV-3. No effect was observed in the other cases. Our data contribute to define a role for gal-1 during the interactions between human ovary carcinoma cells and host fibroblasts. [less ▲]

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See detailRegulation of the alternative oxidase Aox1 gene in Chlamydomonas reinhardtii. Role of the nitrogen source on the expression of a reporter gene under the control of the Aox1 promoter
Baurain, Denis ULiege; Dinant, Monique; Coosemans, Nadine ULiege et al

in Plant Physiology (2003), 131(3), 1418-1430

In higher plants, various developmental and environmental conditions enhance expression of the alternative oxidase (AOX), whereas its induction in fungi is mainly dependent on cytochrome pathway ... [more ▼]

In higher plants, various developmental and environmental conditions enhance expression of the alternative oxidase (AOX), whereas its induction in fungi is mainly dependent on cytochrome pathway restriction and triggering by reactive oxygen species. The AOX of the unicellular green alga Chlamydomonas reinhardtii is encoded by two different genes, the Aox1 gene being much more transcribed than Aox2. To analyze the transcriptional regulation of Aox1, we have fused its 1.4-kb promoter region to the promoterless arylsulfatase (Ars) reporter gene and measured ARS enzyme activities in transformants carrying the chimeric construct. We show that the Aox1 promoter is generally unresponsive to a number of known AOX inducers, including stress agents, respiratory inhibitors, and metabolites, possibly because the AOX activity is constitutively high in the alga. In contrast, the Aox1 expression is strongly dependent on the nitrogen source, being down-regulated by ammonium and stimulated by nitrate. Inactivation of nitrate reductase leads to a further increase of expression. The stimulation by nitrate also occurs at the AOX protein and respiratory levels. A deletion analysis of the Aox1 promoter region demonstrates that a short upstream segment (-253 to +59 with respect to the transcription start site) is sufficient to ensure gene expression and regulation, but that distal elements are required for full gene expression. The observed pattern of AOX regulation points to the possible interaction between chloroplast and mitochondria in relation to a potential increase of photogenerated ATP when nitrate is used as a nitrogen source. [less ▲]

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See detailMembrane type-1 matrix metalloproteinase and TIMP-2 in tumor angiogenesis
Sounni, Nor Eddine ULiege; Janssen, M.; Foidart, Jean-Michel ULiege et al

in Matrix Biology (2003), 22(1), 55-61

The matrix metalloproteinases (MMPs) constitute a multigene family of over 23 secreted and cell-surface associated enzymes that cleave or degrade various pericellular substrates. In addition to virtually ... [more ▼]

The matrix metalloproteinases (MMPs) constitute a multigene family of over 23 secreted and cell-surface associated enzymes that cleave or degrade various pericellular substrates. In addition to virtually all extracellular matrix (ECM) compounds, their targets include other proteinases, chemotactic molecules, latent growth factors, growth factor-binding proteins and cell surface molecules. The MMP activity is controlled by the physiological tissue inhibitors of MMPs (TIMPs). There is much evidence that MMPs and their inhibitors play a key role during extracellular remodeling in physiological situations and in cancer progression. They have other functions that promoting tumor invasion. Indeed, they regulate early stages of tumor progression such as tumor growth and angiogenesis. Membrane type MMPs (MT-MMPs) constitute a new subset of cell surface-associated MMPs. The present review will focus on MT1-MMP which plays a major role at least, in the ECM remodeling, directly by degrading several of its components, and indirectly by activating pro-MMP2. As our knowledge on the field of MT1-MMP biology has grown, the unforeseen complexities of this enzyme and its interaction with its inhibitor TIMP-2 have emerged, often revealing unexpected mechanisms of action. (C) 2003 Elsevier Science B.V/Intemational Society of Matrix Biology. All rights reserved. [less ▲]

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See detailJeunesse, quartiers, violence : pour une politique de prévention intégrée
Comeron, Manuel ULiege

in Manuel de la Police (2003), (67), 166

La violence juvénile, particulièrement dans les quartiers, constitue un problème majeur de sécurité urbaine. A l'éclairage des travaux scientifiques sur la déviance sociale et la délinquance juvénile, les ... [more ▼]

La violence juvénile, particulièrement dans les quartiers, constitue un problème majeur de sécurité urbaine. A l'éclairage des travaux scientifiques sur la déviance sociale et la délinquance juvénile, les intervenants sociaux et services de police construisent des actions communes afin de proposer une réponse préventive intégrée. [less ▲]

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See detailApoptosis induction in human cancer cells by sungucine from Strychnos icaja root
Frederich, Michel ULiege; Bentires-Ali, M.; Tits, Monique ULiege et al

in Naunyn-Schmiedeberg's Archives of Pharmacology (2003), 367(3), 260-265

Sungucine (SG) and isosungucine (ISG) are bisindole alkaloids characterized by a 5'-23 link between the two parts of the compounds, which are till now specific to Strychnos icaja. In this work, SG and ISG ... [more ▼]

Sungucine (SG) and isosungucine (ISG) are bisindole alkaloids characterized by a 5'-23 link between the two parts of the compounds, which are till now specific to Strychnos icaja. In this work, SG and ISG were submitted to the NCI's in vitro 60 human tumor cell line screen, where SG showed interesting selectivity (6X) against the tested leukemia cell lines. In HL60-treated cells, apoptosis was demonstrated by observation of apoptotic bodies formation, and phosphatidylserine exposition at cell surface. In HeLa-treated cells, the analysis of cellular cycle by flow cytometry showed G1 accumulation and a small sub-G1 peak that could be related to DNA fragmentation characteristic of apoptosis. The eventual role of p53 was analyzed using wild-type HCT-116 colon cancer cells. Nevertheless, p53 and Bax expression were not modified in SG-treated cells. The cleavage of PARP by caspase-3 protease proved that apoptosis was also induced in this line. These results demonstrate that SG induces apoptosis, but also necrosis, in human cancer cell lines. [less ▲]

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See detailComparative efficacy of eletriptan 40 mg versus sumatriptan 100 mg
Mathew, N. T.; Schoenen, Jean ULiege; Winner, P. et al

in Headache (2003), 43(3), 214-222

Objective.-To confirm the efficacy advantage of eletriptan 40 mg over sumatriptan 100 mg. Background.-Eletriptan 80 mg has demonstrated significantly greater efficacy when compared to both sumatriptan 50 ... [more ▼]

Objective.-To confirm the efficacy advantage of eletriptan 40 mg over sumatriptan 100 mg. Background.-Eletriptan 80 mg has demonstrated significantly greater efficacy when compared to both sumatriptan 50 mg and 100 mg in two studies. Eletriptan 40 mg demonstrated significantly greater efficacy than sumatriptan 100 mg in one previous trial. Methods.-Two thousand one hundred thirteen patients with a diagnosis of migraine according to International Headache Society criteria were randomized using a double-blind, double-dummy, parallel-group design, and treated for a single migraine attack with either eletriptan 40 mg, sumatriptan 100 mg, or placebo. The primary endpoint was 2-hour headache response. Secondary endpoints included headache response rates at 1 hour, pain-free rates, absence of associated symptoms, functional response at 1 and 2 hours, and sustained headache response. Results.-Headache response rates at 2 hours postdose were significantly higher for eletriptan 40 mg (67%) than for sumatriptan 100 mg (59%; P<.001) and placebo (26%; P <.0001). Eletriptan 40 mg consistently showed significant (P<.01) efficacy over sumatriptan 100 mg across secondary clinical outcomes, including 1-hour headache response; 2-hour pain-free response; absence of nausea, photophobia, and phonophobia; functional improvement; use of rescue medication; treatment acceptability; and sustained headache response (P<.05). Overall, treatment-related adverse events were low, nausea being the only adverse event with an incidence of 2% or higher (4.9% with eletriptan, 4.2% sumatriptan, 2.8% placebo). Conclusion.-This trial confirmed that eletriptan 40 mg offers superior efficacy in treating migraine pain and associated symptoms and in restoring patient functioning when compared with sumatriptan 100 mg. [less ▲]

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See detailThe plant Leclercqia (Lycopsida) in Gondwana: implications for reconstructing Middle Devonian palaeogeography
Meyer-Berthaud, B.; Fairon-Demaret, Muriel ULiege; Steemans, Philippe ULiege et al

in Geological Magazine (2003), 140(2), 119-130

Abundant and well-preserved material of the ligulate lycopsid genus Leclercqia is reported from a new Middle Devonian locality in northeastern Queensland (Australia). The plants occur in a chert horizon ... [more ▼]

Abundant and well-preserved material of the ligulate lycopsid genus Leclercqia is reported from a new Middle Devonian locality in northeastern Queensland (Australia). The plants occur in a chert horizon in the Storm Hill Sandstone of the Dosey-Craigie Platform. Lithological data and conodont analyses combined with information from in situ spores provide an age for the plant levels ranging from Eifelian, possibly Middle Eifelian, to Early Givetian. Plant taxonomic identification is based on vegetative and fertile stems that display both external morphology and anatomy. This material represents the best documented occurrence of Leclercqia outside Laurussia and possibly the earliest in Gondwana; it provides evidence that colonization of Gondwana by the species L. complexa was contemporaneous to that of Siberia and Kazakhstan. Analysis of the distribution patterns of L. complexa suggests that it was adapted to a wide range of environments, but within certain limits which we hypothesize to be those of a climatic belt. Such considerations support previous studies using other biological data, such as faunas and palynomorphs, for reconstructing Devonian palaeogeography. They favour a close proximity of Laurussia and Gondwana rather than the occurrence of a wide ocean separating the two palaeocontinents in Middle Devonian times. [less ▲]

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See detailTranssexualisme et Rorschach: une revue de la littérature
Michel, Aude; Mormont, Christian ULiege

in Annales Médico Psychologiques (2003), 161(2), 125-131

The Rorschach test appears as the main projective method used to investigated the personality of sex reassignment candidates. We shall first look at studies testing, the hypothesis of troubled background ... [more ▼]

The Rorschach test appears as the main projective method used to investigated the personality of sex reassignment candidates. We shall first look at studies testing, the hypothesis of troubled background. In a second time, we will analyze the hypothesis of independent issue. Finally, we will present the few follow up studies built up with the Rorschach test. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved. [less ▲]

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See detailPolymer/layered silicate nanocomposites by combined intercalative polymerization and melt intercalation: a masterbatch process
Lepoittevin, Bénédicte; Pantoustier, Nadège; Devalckenaere, Myriam et al

in Polymer (2003), 44(7), 2033-2040

Poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) layered silicate nanocomposites were prepared by combination of intercalative polymerization and melt intercalation. In a first step, high clay ... [more ▼]

Poly(ε-caprolactone) (PCL) and poly(vinyl chloride) (PVC) layered silicate nanocomposites were prepared by combination of intercalative polymerization and melt intercalation. In a first step, high clay content PCL nanocomposites were prepared by in situ polymerization of -caprolactone intercalated between selected organo-modified silicate layers. The polymerization was catalyzed with dibutyltin dimethoxide in the presence of montmorillonites, the surface of which were previously exchanged with (functionalized) long alkyl chains ammonium cations. Then, these highly filled PCL nanocomposites were added as masterbatches in commercial PCL and PVC by melt blending. The intercalation of PCL chains within the silicate layers by in situ polymerization proved to be very efficient, leading to the formation of intercalated and/or exfoliated structures depending on the organo-clay. These masterbatches were readily dispersed into the molten PCL and PVC matrices yielding intercalated/exfoliated layered silicate nanocomposites which could not be obtained by melt blending the matrix directly with the same organo-modified clays. The formation of nanocomposites was assessed both by X-ray diffraction and transmission electronic microscopy. Interestingly, this so-called 'masterbatch' two-step process allowed for preparing PCL nanocomposites even with non-modified natural clay, i.e. sodium montmorillonite, which showed a material stiffness much higher than the corresponding microcomposites recovered by direct melt intercalation. The thermal stability of PCL nanocomposites as a function of clay content was investigated by thermogravimetry (TGA). [less ▲]

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See detailJoint Mobility in Adult Patients with Groin Hernias
Pans, Alain ULiege; Albert, Adelin ULiege

in Hernia : the Journal of Hernias & Abdominal Wall Surgery (2003), 7(1), 21-4

The basic mechanisms of hernia formation remain mostly unknown, but several studies suggest that a connective-tissue pathology, affecting mainly the collagen metabolism, could play a role in the genesis ... [more ▼]

The basic mechanisms of hernia formation remain mostly unknown, but several studies suggest that a connective-tissue pathology, affecting mainly the collagen metabolism, could play a role in the genesis of groin hernias. It would be interesting to know if this pathology can express some clinical signs other than the hernia. Our study focused on the joint mobility and the diagnostic criteria for benign joint hypermobility syndrome. Sixty male adult patients with inguinal hernias and 62 control subjects without hernias, age-matched, were compared, taking into account anamnestic criteria (family history of groin hernia, joint sprain, joint dislocation, skin striae, major arthralgia) and joint mobility. This was assessed by using Beighton criteria and measuring the range of movement of five joints (extension of the fifth finger, thumb, wrist, elbow, and knee). The frequency of the positive anamnestic criteria was not statistically different between the two groups. Nevertheless, a family history of groin hernia was observed in 25% of the hernia patients, against 16% in the control subjects ( P=0.23). The mean Beighton score was 0.30 in the hernia patients and 0.29 in the control population. The movement range of the five examined joints was similar in the two groups. In conclusion, patients with a groin hernia presented neither joint hypermobility nor clinical evidence of a benign joint hypermobility syndrome. Although abnormal collagen metabolism is likely implicated in hernia formation, this pathology does not seem to have clinical repercussion on joint mobility. [less ▲]

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See detailAdhesion of endometrial cells labeled with 111 Indium-tropolonate to peritoneum: a novel in vitro model to study endometriosis
Beliard, Aude ULiege; Noël, Agnès ULiege; Goffin, Frédéric ULiege et al

in Fertility and Sterility (2003), 79(Suppl. 1), 724-729

Objective: To evaluate, in a new original in vitro assay, putative factors that could modulate the adhesion of endometrial cells to peritoneum. Design: Prospective, controlled in vitro study. Setting ... [more ▼]

Objective: To evaluate, in a new original in vitro assay, putative factors that could modulate the adhesion of endometrial cells to peritoneum. Design: Prospective, controlled in vitro study. Setting: Academic research laboratory. Patient(s): Fourteen nonmenopausal women undergoing hysterectomy or laparoscopy for benign gynecologic indication. Intervention(s): Endometrial cells obtained from women with regular cycles without endometriosis were labeled with (111)Indium and confronted in vitro with mouse peritoneum in the presence of various cytokines and/or antiadhesive compounds. Main Outcome Measure(s): Radioactivity in (111)Indium-labeled endometrial cells. Result(s): The adhesion of human endometrial cells to mouse peritoneum was increased by treatment with pro-inflammatory cytokines (interleukin IL-1 beta, IL-6, TNF alpha, TGF-beta1). Whereas heparan sulfate had no effect on cell adhesion, a gel of ferric hyaluronate (Intergel) was able to counteract the pro-adhesive effect of cytokines. Interestingly, the pretreatment of peritoneum with cytokines, 24 hours before cell seeding in the presence of the ferric hyaluronate gel, restored the cytokine-promoting effect on cell adhesion. Conclusion(s): Proinflammatory cytokines promote the in vitro peritoneal adhesion of endometrial cells. An antiadhesive hyaluronate gel used in clinics decreases the adhesion in a dose-dependent manner and reduces cytokine bioavailability. (Fertil Steril((R)) 2003;79(Suppl 1):724-9. (C) 2003 by American Society for Reproductive Medicine.). [less ▲]

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See detailLong-term results of cardiac and general health status in children after neonatal arterial switch operation.
Hovels-Gurich, Hedwig H; SEGHAYE, Marie-Christine ULiege; Ma, Qing et al

in Annals of Thoracic Surgery (2003), 75(3), 935-43

BACKGROUND: The purpose of this study was to assess cardiac and general health status 8 to 14 years after neonatal arterial switch operation for transposition of the great arteries. METHODS: Sixty ... [more ▼]

BACKGROUND: The purpose of this study was to assess cardiac and general health status 8 to 14 years after neonatal arterial switch operation for transposition of the great arteries. METHODS: Sixty unselected children with intact ventricular septum (78.3%) or ventricular septal defect (21.7%) without or with aortic isthmic stenosis (5.1%) were examined 10.5 +/- 1.6 (mean +/- SD) years after neonatal switch and 5.3 +/- 1.6 years after mid-term evaluation. Complete clinical examination, standard and 24-hour Holter electrocardiogram, M-mode, 2D-, Doppler, and color Doppler echocardiography were performed. Results were compared with normal values and to mid-term follow-up results. RESULTS: Rates of reoperation after arterial switch operation and operation to correct concomitant coarctation were 3.3% and 5.1%, respectively. No patient needed medication, and 93.3% had no limitation of physical activity. All children had normal height and weight; 31.6% had abnormal thoracic configuration after median sternotomy. Most patients (91.7%) were in sinus rhythm. Incidence of complete right bundle branch block (10.0%) was unchanged, as was prevalence of ectopic activity (occasional atrial ectopy 20.0%, ventricular ectopy: occasional 21.7%; frequent 1.7%). Left ventricular dimensions and shortening fraction did not change over time. Diameters of neo-aortic valve annulus and neo-aortic root did not increase, and z-scores decreased between mid-term and present evaluation. Incidence of neo-aortic insufficiency was 13.3% and remained unchanged in comparison with the pre-examination value. Neo-aortic stenosis was not seen. Compared with mid-term follow-up, incidence (41.6%) and degree of supravalvular pulmonary stenosis increased. CONCLUSIONS: Good cardiac results persist 10 years after neonatal arterial switch operation for transposition of the great arteries. Encouraging findings include preservation of left ventricular function, low incidence of rhythm disturbances, lack of further neo-aortic root dilatation, and unchanged incidence of neo-aortic insufficiency compared with mid-term follow-up. Increased incidence and degree of supravalvular pulmonary stenosis are of concern. [less ▲]

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See detailLe mariage des couples du même sexe: un nouveau droit familial venu du nord?
Leleu, Yves-Henri ULiege

in 15e Jour du Mois (Le) (2003)

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See detailGeneralized (m, k)-Zipf law for fractional Brownian motion-like time series with or without effect of an additional linear trend
Bronlet, Philippe ULiege; Ausloos, Marcel ULiege

in International Journal of Modern Physics C (2003), 14(3), 351-365

We have translated fractional Brownian motion (FBM) signals into a text based on two "letters", as if the signal fluctuations correspond to a constant stepsize random walk. We have applied the Zipf method ... [more ▼]

We have translated fractional Brownian motion (FBM) signals into a text based on two "letters", as if the signal fluctuations correspond to a constant stepsize random walk. We have applied the Zipf method to extract the zeta' exponent relating the word frequency and its rank on a log-log plot. We have studied the variation of the Zipf exponent(s) giving the relationship between the frequency of occurrence of words of length m < 8 made of such two letters: zeta' is varying as a power law in terms of m. We have also searched how the zeta' exponent of the Zipf law is influenced by a linear trend and the resulting effect of its slope. We can distinguish finite size effects, and results depending whether the starting FBM is persistent or not, i.e., depending on the FBM Hurst exponent H. It seems then numerically proven that the Zipf exponent of a persistent signal is more influenced by the trend than that of an antipersistent signal. It appears that the conjectured law zeta' = \2H - 1\ only holds near H = 0.5. We have also introduced considerations based on the notion of a time dependent Zipf law along the signal. [less ▲]

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See detailAdéquation entre les formations existantes en éducation physique, les motivations des étudiants et les différents débouchés professionnels.
Carlier, Ghislain; Gaspard, Laurent; Gérard, Philippe et al

in Point sur la Recherche en Education (Le) (2003), 27

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See detailAnomalies du metabolisme osseux chez les patients infectes par le HIV et traites par tritherapie
GIOT, Jean-Baptiste ULiege; Franchimont, N.; Moutschen, Michel ULiege

in Revue Médicale de Liège (2003), 58(3), 155-63

For several years already, a growing number of studies reports modifications in the bone metabolism among HIV-infected patients. Some of these studies, published even before the use of HAART, involved the ... [more ▼]

For several years already, a growing number of studies reports modifications in the bone metabolism among HIV-infected patients. Some of these studies, published even before the use of HAART, involved the infection itself. With the experience already available as concerns HAART, antiretroviral treatments (ART) seem however to be called into question. Data are divergent yet. Some studies tend to invalidate the collected data about the harmful role of HAART and prove the absence of effect or even the beneficial action of ART on bone. Moreover, the three important classes of ART are implied, even if the proteases inhibitors are most commonly charged. Pathogenic mechanism remain hypothetical. While the impact on morbidity seems to be weak for the time being, long-term repercussions are still unknown, in particular when children are concerned. In such conditions, it appears difficult to set up coherent politics of screening, prevention and treatment. Nevertheless beyond the divergences, the multifactorial character of alteration of HIV-infected patient's bone metabolism seems to be undeniable. The identification of the different parameters should in the future clarify the situation and enable the publishing of exact criteria of screening, prevention and treatment. [less ▲]

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See detailOzone et asthme: un couple dans l'air du temps
Kleis, S.; Louis, Renaud ULiege; Bartsch, Pierre ULiege

in Revue Médicale de Liège (2003), 58(3), 132-8

Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in ... [more ▼]

Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in asthma. Experimental studies have shown that exposure of healthy subjects and asthmatics to ozone levels comparable to those measured in ambient air during hot summer days can generate respiratory symptoms, neutrophilic airways inflammation and lung function impairment. Lung function changes following ozone exposure are more pronounced in asthmatics and are dependent on the duration and intensity of exposure, a previous exposure and the nutritional status of the subjects. The airway epithelial cell layer is likely to play a pivotal role in initiating the inflammatory process following ozone exposure. Control of ambient air ozone levels must be a target for public health authorities. [less ▲]

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See detailModelling the impact of benthic filter-feeders on the composition and biomass of river plankton
Descy, Jean-Pierre; Everbecq, Etienne ULiege; Gosselain, Véronique ULiege et al

in Freshwater Biology (2003), 48(3), 404-417

1. The POTAMON model [Everbecq E. et al. (2001) Water Research, 35, 901] has been used to simulate the effect of benthic bivalves (mainly Dreissena polymorpha ) on the phytoplankton and zooplankton in a ... [more ▼]

1. The POTAMON model [Everbecq E. et al. (2001) Water Research, 35, 901] has been used to simulate the effect of benthic bivalves (mainly Dreissena polymorpha ) on the phytoplankton and zooplankton in a lowland Western European river (the Moselle). Here we use a modified version of the POTAMON model with five categories of phytoplankton (Stephanodiscus, Cyclotella -like, large diatoms, Skeletonema and non-siliceous algae) to model filter-feeding effects of benthic bivalves in the Moselle. Zooplankton has been represented in the model by two categories, Brachionus -like and Keratella -like rotifers. 2. According to density estimates from field surveys (Bachmann V. et al. (1995) Hydroecologie Appliquee, 7, 185, Bachmann V. & Usseglio-Polatera P. (1999) Hydrobiologia, 410, 39), zebra mussel density varied among river stretches, and increased through the year to a maximum in summer. Dreissena filtration rates from the literature were used, and mussels have been assumed to feed on different phytoplankton categories (but less on large and filamentous diatoms) as well as on rotifers. 3. The simulations suggest a significant impact of benthic filter-feeders on potamoplankton and water quality in those stretches where the mussels are abundant, their impact being maximal in summer. Consequently, different plankton groups were not affected to the same extent, depending on their period of development and on indirect effects, such as predation by mussels on herbivorous zooplankton. 4. A daily carbon balance for a typical summer shows the effect of benthic filter-feeders on planktonic and benthic processes: the flux of organic matter to the bottom is greatly enhanced at high mussel density; conversely, production and breakdown of organic carbon in the water column are reduced. Mussel removal would drive the carbon balance of the river toward autotrophy only in the downstream stretches. [less ▲]

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See detailOccupational stress and burnout in anaesthesia
Nyssen, Anne-Sophie ULiege; Hansez, Isabelle ULiege; Baele, Philippe et al

in British Journal of Anaesthesia (2003), 90(3), 333-337

Background. Formal studies on stress in anaesthetists have usually measured stress through mental or physiological indicators. When using this approach, one must be careful not to confuse the effects of ... [more ▼]

Background. Formal studies on stress in anaesthetists have usually measured stress through mental or physiological indicators. When using this approach, one must be careful not to confuse the effects of stress or outcome variables and the sources of stress or antecedent variables. To date, it seems from the literature that there is no clear evidence of a common pattern of physiological effects of stress for all the sources of stress. Furthermore, work characteristics such as job satisfaction, job control and job support may moderate the effects of stress. Methods. We measured the effects of stress together with the sources of stress and job characteristics, using self-reported questionnaires rather than physiological indicators in order to better diagnose stress in anaesthetists. Results. The mean stress level in anaesthetists was 50.6 which is no higher than we found in other working populations. The three main sources of stress reported were a lack of control over time management, work planning and risks. Anaesthetists reported high empowerment, high work commitment, high job challenge and high satisfaction. However, 40.4% of the group were suffering from high emotional exhaustion (burnout); the highest rate was in young trainees under 30 years of age. Conclusions. Remedial actions are discussed at the end of the paper. [less ▲]

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See detailThe low-energy limit of validity of the intranuclear cascade model
Cugnon, Joseph ULiege; Henrotte, Pascal ULiege

in European Physical Journal A -- Hadrons & Nuclei (2003), 16(3), 393-407

The intranuclear cascade model is generally considered to be valid when the incident particle has a sufficiently small de Broglie wavelength to interact with individual nucleons. On this basis, a lower ... [more ▼]

The intranuclear cascade model is generally considered to be valid when the incident particle has a sufficiently small de Broglie wavelength to interact with individual nucleons. On this basis, a lower limit of 200 MeV is usually quoted for the incident energy in nucleon-induced reactions. Here this statement is questioned. A pragmatic approach is used, which compares the predictions of the Liege intranuclear cascade model with available data at incident energy between 40 and 250 MeV. It is found that this model gives surprisingly good results at energies well below the limit mentioned above. Results are also compared with the predictions of other models commonly used in this energy range. [less ▲]

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See detailDetective Bogman in Berlijn
Spinoy, Erik ULiege

in Literatuur (2003), 20(2), 45

This is a review of a book on the 'Berlin years' of the Flemish writer Paul van Ostaijen.

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See detailL'image du mois. Artere coronaire unique ou tronc commun occlus collateralise?
Gach, Olivier ULiege; Troisfontaines; LEGRAND, Victor ULiege

in Revue Médicale de Liège (2003), 58(3), 117-8

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See detailToxicite pulmonaire de la gemcitabine dans le cadre d'un CPNPC avec carcinomatose cerebrale
Mommens, Véronique; Bosquee, Léon ULiege; D'Orio, Vincenzo ULiege

in Revue Médicale de Liège (2003), 58(3), 123-6

Gemcitabine pulmonary toxicity is rare and represents a difficult diagnosis. A 61 year old female treated with gemcitabine for a metastatic non-small cell lung cancer (NSCLC) developed during the fifth ... [more ▼]

Gemcitabine pulmonary toxicity is rare and represents a difficult diagnosis. A 61 year old female treated with gemcitabine for a metastatic non-small cell lung cancer (NSCLC) developed during the fifth chemotherapy cycle an acute respiratory distress syndrome with fever, tachypnea, marked hypoxemia and a diffuse interstitial-alveolar infiltrate on chest radiograph. No infectious or opportunistic etiology or cardiovascular disease was demonstrated. Withdrawal of gemcitabine and administration of corticosteroids led to symptomatic improvement. This acute pneumonitis was likely drug induced. [less ▲]

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See detailAnalysis of polychlorinated biphenyl residues in human plasma by gas chromatography-mass spectrometry
Charlier, Corinne ULiege; Dubois, Nathalie ULiege; CUCCHIARO, Séverine ULiege et al

in Journal of Analytical Toxicology (2003), 27(2), 74-77

A method for the determination of seven polychlorinated biphenyl residues in plasma by gas chromatography-mass spectrometry was developed. The analytes were isolated from human plasma by liquid-liquid ... [more ▼]

A method for the determination of seven polychlorinated biphenyl residues in plasma by gas chromatography-mass spectrometry was developed. The analytes were isolated from human plasma by liquid-liquid extraction, followed by solid-phase extraction, and separation on an HP5 Trace column. Ionization mode was electronic impact, and selected ion storage was used for isolation and quantitation of the compounds. The method was evaluated for its analytical performances and therefore applied to monitor the prevalence of these seven polychlorinated biphenyl residues in a female population. Eighty samples were analyzed, and 82.5% presented detectable amounts of at least one residue. For the population study, results were reported on a lipid-adjusted basis. Because the proposed method is satisfying and seems to be suitable for the quantitation of PCB congeners in a general population, epidemiological studies to evaluate the widespread contamination with these environmental compounds can be proposed. [less ▲]

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See detailA comparison of voluntary and electrically induced contractions by interleaved H-1- and P-31-NMRS in humans
Vanderthommen, Marc ULiege; Duteil, S.; Wary, C. et al

in Journal of Applied Physiology (2003), 94(3), 1012-1024

Skeletal muscle voluntary contractions (VC) and electrical stimulations (ES) were compared in eight healthy men. High-energy phosphates and myoglobin oxygenation were simultaneously monitored in the ... [more ▼]

Skeletal muscle voluntary contractions (VC) and electrical stimulations (ES) were compared in eight healthy men. High-energy phosphates and myoglobin oxygenation were simultaneously monitored in the quadriceps by interleaved H-1- and P-31-NMR spectroscopy. For the VC protocol, subjects performed five or six bouts of 5 min with a workload increment of 10% of maximal voluntary torque (MVT) at each step. The ES protocol consisted of a 13-min exercise with a load corresponding to 10% MVT. For both protocols, exercise consisted of 6-s isometric contractions and 6-s rest cycles. For an identical mechanical level (10% MVT), ES induced larger changes than VC in the P-i-to-phosphocreatine ratio [1.38 +/- 1.14 (ES) vs. 0.13 +/- 0.04 (VC)], pH [6.69 +/- 0.11 (ES) vs. 7.04 +/- 0.07 (VC)] and myoglobin desaturation [43 +/- 15.9 (ES) vs. 6.1 +/- 4.6% (VC)]. ES activated the muscle facing the NMR coil to a greater extent than did VCs when evaluated under identical technical conditions. This metabolic pattern can be interpreted in terms of specific temporal and spatial muscle cell recruitment. Furthermore, at identical levels of energy charge, the muscle was more acidotic and cytoplasm appeared more oxygenated during ES than during VC. These results are in accordance with a preferential recruitment of type II fibers and a relative muscle hyperperfusion during ES. [less ▲]

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See detailImage analysis of the axonal ingrowth into poly(D,L-lactide) porous scaffolds in relation to the 3-D porous structure
Blacher, Silvia ULiege; Maquet, Véronique; Luyckx, Françoise ULiege et al

in Biomaterials (2003), 24(6), 1033-1040

Porous polymer scaffolds are promising materials for neural tissue engineering because they offer valuable three-dimensional (3D) supports for the in vitro and in vivo axonal growth and tissue expansion ... [more ▼]

Porous polymer scaffolds are promising materials for neural tissue engineering because they offer valuable three-dimensional (3D) supports for the in vitro and in vivo axonal growth and tissue expansion. At the time being, how the in vivo neuronal cell development depends on the scaffold 3-D architecture is unknown. Therefore, scanning electron micrographs of longitudinal sections of porous polylactide scaffolds and immunohistological sections of these scaffolds after implantation and neurofilament staining have been studied by image analysis. Pore orientation and axonal ingrowth have been investigated by spectral analysis on gray level SEM images. Binary image processing has been carried out and the binary images have been studied by spectral analysis in order to estimate the possible effect of the image noise on the real pattern. In addition to axonal orientation, density and length distribution of the regenerated axons into the polymer scaffold have been measured. Dependence of the axonal ingrowth on the 3D-polymer scaffold has been discussed on the basis of the collected data. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailIsostrychnopentamine, an indolomonoterpenic alkaloid from Strychnos usambarensis, induces cell cycle arrest and apoptosis in human colon cancer cells
Frederich, Michel ULiege; Bentires-Alj, M.; Tits, Monique ULiege et al

in Journal of Pharmacology and Experimental Therapeutics (2003), 304(3), 1103-1110

Isostrychnopentamine (ISP) is an indolomonoterpenic alkaloid that is present in the leaves of Strychnos usambarensis, a well known African shrub or little tree. The roots contain quaternary alkaloids ... [more ▼]

Isostrychnopentamine (ISP) is an indolomonoterpenic alkaloid that is present in the leaves of Strychnos usambarensis, a well known African shrub or little tree. The roots contain quaternary alkaloids, which are used to make a curare-like arrow poison. However, tertiary alkaloids isolated from the same plant possess cytotoxic activities against mammalian cells and protozoa. The effect of ISP has been investigated on the growth and viability of HCT-116 colon cancer cells during their exponentially growing phase. ISP induced apoptotic cell death as shown by the translocation of phosphatidylserine from the inner layer to the outer layer of the plasma membrane, chromatin condensation, DNA fragmentation, and caspase-3 and -9 activation. ISP provoked also cell cycle arrest in the G(2)-M phase. We also showed that the expression of p53 was not modified in ISP-treated cells, but that p21 was induced in a p53-independent manner. Finally, we demonstrated that ISP did not affect the catalytic activity of human topoisomerases I and II. In conclusion, ISP, which promotes cell death by a p53-independent apoptotic pathway, could be an interesting lead for cancer chemotherapy. [less ▲]

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See detailThe structure of a cold-adapted family 8 xylanase at 1.3 angstrom resolution - Structural adaptations to cold and investigation of the active site
Van Petegem, F.; Collins, T.; Meuwis, Marie-Alice ULiege et al

in Journal of Biological Chemistry (2003), 278(9), 7531-7539

Enzymes from psychrophilic organisms differ from their mesophilic counterparts in having a lower thermo-stability and a higher specific activity at low and moderate temperatures. The current consensus is ... [more ▼]

Enzymes from psychrophilic organisms differ from their mesophilic counterparts in having a lower thermo-stability and a higher specific activity at low and moderate temperatures. The current consensus is that they have an increased flexibility, enhancing accommodation and transformation of the substrates at low energy costs. Here we describe the structure of the xylanase from the Antarctic bacterium Pseudoalteromonas haloplanktis at 1.3 Angstrom resolution. Xylanases are usually grouped into glycosyl hydrolase families 10 and 11, but this enzyme belongs to family 8. The fold differs from that of other known xylanases and can be described as an (alpha/alpha)(6) barrel. Various parameters that may explain the cold-adapted properties were examined and indicated that the protein has a reduced number of salt bridges and an increased exposure of hydrophobic residues. The crystal structures of a complex with xylobiose and of mutant D144N were obtained at 1.2 and 1.5 A resolution, respectively. Analysis of the various substrate binding sites shows that the +3 and -3 subsites are rearranged as compared to those of a family 8 homolog, while the xylobiose complex suggests the existence of a +4 subsite. A decreased acidity of the substrate binding cleft and an increased flexibility of aromatic residues lining the subsites may enhance the rate at which substrate is bound. [less ▲]

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See detailKinetics of circulating antigens in pigs experimentally infected with Taenia solium eggs
Nguekam, A.; Zoli, A. P.; Vondou, L. et al

in Veterinary Parasitology (2003), 111(4), 323-332

Three groups of four piglets were experimentally infected with different doses (10(3), 10(4) and 10(5)) of Taenia solium eggs whereas a fourth group of two pigs received gravid proglottids. At autopsy 6 ... [more ▼]

Three groups of four piglets were experimentally infected with different doses (10(3), 10(4) and 10(5)) of Taenia solium eggs whereas a fourth group of two pigs received gravid proglottids. At autopsy 6 months post infection, the two latter pigs were heavily infected with more than 3000 living cysts per kg of muscle. Ten of the 12 other pigs harboured light infections, i.e. between 2 and 107 cysticerci, 42.4% of which were degenerated. The two remaining pigs had no detectable cysts at post mortem examination. Circulating antigens (CA) were detected in the sera of all pigs harbouring living cysticerci using a monoclonal antibody based ELISA. CA were first detected between 2 and 6 weeks post infection and remained present generally throughout the entire observation period even in pigs carrying only five to eight living cysts, although strong fluctuations of the level of CA were observed in some pigs. In animals without living cysts at post mortem CA were only detected for a short period and disappeared presumably when the cysticerci became degenerated. The minimum number of living cysts, which could be detected using this ELISA, was 1. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailRéforme de la Cour d’arbitrage – Une révolution de velours ?
Rosoux, Géraldine ULiege

in Journal du Juriste (2003), 19

Cet article présente les grandes lignes de la réforme, opérée en 2003, de la juridiction constitutionnelle belge.

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See detailAn energy transfer study of homopolymer localization in block copolymers
Rharbi, Yahya; Zhang, Jian-Xin; Spiro, John G et al

in Macromolecules (2003), 36(4), 1241-1252

We have investigated the localization of homopolystyrene (hPS) in its blends with poly(styrene-b-butyl methacrylate) (PS-b-PBMA), at 140 degreesC, measuring the quantum efficiency of direct energy ... [more ▼]

We have investigated the localization of homopolystyrene (hPS) in its blends with poly(styrene-b-butyl methacrylate) (PS-b-PBMA), at 140 degreesC, measuring the quantum efficiency of direct energy transfer (Phi(ET) of DET) between hPS randomly labeled with phenanthrene moieties and PS-b-PBMA labeled at the junction with anthracene. The molecular weight of hPS was similar to the molecular weight of the PS block of PS-b-PBMA, and the hPS content was kept to a maximum of 26 vol %, to preserve the lamellar morphology of PS-b-PBMA. We have found very low rates of DET, which implies that hPS is almost totally localized between the PS brushes of PS-b-PBMA. In addition to the experimental measurements, we also calculated Phi(ET) values by simulating fluorescence decay curves, based on Vavasour and Whitmore's numerical self-consistent-field (NSCF) formalism. The latter theory confirmed that we were dealing with a "dry brush" situation, but the NSCF results suggested a higher level of penetration of hPS than the experiments. We attribute this discrepancy to uncertainties about inputs to the simulations, particularly the Flory-Huggins chi parameter and the Kuhn length for the PBMA block. [less ▲]

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See detailControlled free radical polymerization of styrene initiated from alkoxyamine attached to polyacrylate chemisorbed onto conducting surfaces
Voccia, Samuël; Jérôme, Christine ULiege; Detrembleur, Christophe ULiege et al

in Chemistry of Materials (2003), 15(4), 923-927

A new inimer that associates an alkoxyamine, which is an initiator/mediator in nitroxide mediated radical polymerization (NMP), and a polymerizable acrylate has been synthesized and used in a two-step ... [more ▼]

A new inimer that associates an alkoxyamine, which is an initiator/mediator in nitroxide mediated radical polymerization (NMP), and a polymerizable acrylate has been synthesized and used in a two-step "grafting-from" method. The acrylate has been first electropolymerized under a cathodic potential, such that the polymer is chemisorbed on the cathode. NMP of styrene has then been initiated from the electrografted polyacrylate chains with formation of polystyrene with controlled molecular weight and narrow polydispersity. [less ▲]

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See detailNovel aliphatic polyesters based on functional cyclic (di)esters
Lou, Xudong; Detrembleur, Christophe ULiege; Jérôme, Robert ULiege

in Macromolecular Rapid Communications (2003), 24(2), 161-172

Recent progress in the chemical synthesis of novel aliphatic polyesters via ring-opening polymerization of functional cyclic (di)esters are reviewed in this article. Syntheses of these functional ... [more ▼]

Recent progress in the chemical synthesis of novel aliphatic polyesters via ring-opening polymerization of functional cyclic (di)esters are reviewed in this article. Syntheses of these functional aliphatic polyesters are being classified into three groups according to the structure of the cyclic monomers: (i) cyclic diesters, (ii) morpholine-2,5-dione derivatives, and (iii) cyclic esters. Progress in the synthesis and polymerization of monomers in each category is reported with an emphasis on controlled synthesis. The recent achievements have enabled the synthesis of a variety of novel aliphatic polyesters, including hydrophilic, halogenated, and unsaturated polyesters. [less ▲]

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See detailPreparation of supported yttrium alkoxides as catalysts for the polymerization of lactones and oxirane
Martin, Eric; Dubois, Philippe ULiege; Jérôme, Robert ULiege

in Journal of Polymer Science. Part A, Polymer Chemistry (2003), 41(4), 569-578

Two methods have been reported that allow yttrium alkoxides to be supported on porous silica and to be used afterward as heterogeneous catalysts in the ring-opening polymerization of oxirane and e ... [more ▼]

Two methods have been reported that allow yttrium alkoxides to be supported on porous silica and to be used afterward as heterogeneous catalysts in the ring-opening polymerization of oxirane and e-caprolactone. In the two methods, [tris(hexamethyldisilyl)-amide]yttrium [Y[N(SiMe3)(2)](3)} is the metal alkoxide precursor. It is directly reacted with the silanol groups of the support, in the first method, and this is followed by alcoholysis of the unreacted amide groups. The flexibility of this method seems to be limited because the grafting density and the structure of the grafted Y alkoxide (less than one alkoxide by metal) are independent of the experimental conditions. In the second method, Y[N(SiMe3)(2)](3) is first reacted with 1 or 2 equiv of alcohol with the formation of the mixed Y alkoxide/amide. The amide functions are used to attach Y to the support. This method is free from side reactions, quite reproducible, and well suited to support one type of active species (monoalkoxide or dialkoxide). Preliminary experiments with e-caprolactone polymerization have confirmed the activity of the supported Y alkoxide, whatever preparation method is used. (C) 2003 Wiley Periodicals, Inc. [less ▲]

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See detailIdentification of HTF (HER2 transcription factor) as an AP-2 (activator protein-2) transcription factor and contribution of the HTF binding site to ERBB2 gene overexpression
Vernimmen, Douglas; Begon, Dominique ULiege; Salvador, Christophe et al

in Biochemical Journal (2003), 370(Pt 1), 323-329

The ERBB2 gene is overexpressed in 30% of human breast cancers and this is correlated with poor prognosis. Overexpression of the ERBB2 gene is due to increased transcription and gene amplification. Our ... [more ▼]

The ERBB2 gene is overexpressed in 30% of human breast cancers and this is correlated with poor prognosis. Overexpression of the ERBB2 gene is due to increased transcription and gene amplification. Our previous studies have identified a new cis element in the ERBB2 promoter which is involved in the gene's overexpression. This cis element, located 501 bp upstream from the main ERBB2 transcription initiation site, binds a transcription factor called HTF (HER2 transcription factor). We report here the identification of HTF as an AP-2 (activator protein-2) transcription factor. The new cis element is bound by AP-2 with high affinity, compared with a previously described AP-2 binding site located 284 bp downstream. Co-transfection of an AP-2alpha expression vector with a reporter vector containing the newly identified AP-2 binding site in front of a minimal ERBB2 promoter induced a dose-dependent increase in transcriptional activity. We examined the contribution of the new AP-2 binding site to ERBB2 overexpression. For this purpose we abolished the new and/or the previously described AP-2 binding sequence by site-directed mutagenesis. The results show that the two functional AP-2 sites in the first 700 bp of the ERBB2 promoter co-operate to achieve maximal transcriptional activity. [less ▲]

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See detailObservation of dayside subauroral proton flashes with the IMAGE-FUV imagers
Hubert, Benoît ULiege; Gérard, Jean-Claude ULiege; Fuselier, S. A. et al

in Geophysical Research Letters (2003), 30(3),

[1] A detailed description of an intense flash of auroral emissions that occurs equatorward of the dayside auroral oval observed with the IMAGE-FUV imagers is presented. The comparison of simultaneous ... [more ▼]

[1] A detailed description of an intense flash of auroral emissions that occurs equatorward of the dayside auroral oval observed with the IMAGE-FUV imagers is presented. The comparison of simultaneous snapshots of this subauroral flash obtained with the three FUV cameras indicates that proton precipitation is dominant. This transient proton aurora is triggered by the sudden increase of a solar wind dynamic pressure pulse. It occurs on closed field lines mapping to the equatorial plane at distances as small as similar to4 RE. A second similar event is presented, and several other cases are mentioned. These shock induced transcient emissions develop with a time scale of a few minutes (typically similar to5 min), and have a relaxation time on the order of similar to10 minutes. [less ▲]

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See detailEnantiomer separation of N-protected amino acids by non-aqueous capillary electrophoresis and high-performance liquid chromatography with tert.-butyl carbamoylated quinine in either the background electrolyte or the stationary phase
Piette, Véronique; Lammerhofer, M.; Lindner, W. et al

in Journal of Chromatography. A (2003), 987(1-2), 421-427

A non-aqueous CE method was developed for evaluating the chiral discrimination potential of cinchona alkaloids and different kinds of carbamoylated derivatives of quinine and quinidine type chiral ... [more ▼]

A non-aqueous CE method was developed for evaluating the chiral discrimination potential of cinchona alkaloids and different kinds of carbamoylated derivatives of quinine and quinidine type chiral selectors towards acidic analytes, in particular a series of various Bz (benzoyl), DNB (3,5-dinitrobenzoyl) and DNZ (3,5-dinitrobenzyloxycarbonyl) amino acid derivatives. In this study, the enantioselectivity values obtained in non-aqueous CE with tert-butyl carbamoylated quinine as chiral additive have been compared with the values found for the same series of selectands in HPLC using the same selector immobilized onto silica as chiral stationary phase. Similarly to the background electrolyte used in CE an ethanol-methanol mixture (60:40, v/v) containing 100 mM octanoic acid and 12.5 mM ammonia has been selected as HPLC mobile phase. Under these conditions, a good correlation (r=0.954) between the enantioselectivities observed with the two techniques has been obtained. Thus the non-aqueous CE method can be applied as a screening tool for the rapid evaluation of the chiral discrimination potential of a large set of newly developed chiral selectors derived from quinine and related alkaloids. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailTime-resolved laser-induced fluorescence measurements of Rydberg states in Lu I and comparison with theory
Dai, Z. W.; Jiang, Z. K.; Xu, H. L. et al

in Journal of Physics B-Atomic Molecular and Optical Physics (2003), 36(3), 479-487

Time-resolved laser-induced fluorescence measurements have been performed for ten odd Rydberg states of neutral lutetium, belonging to the 6s(2)(S-1)np(n = 8-9) and 6 s(2)(S-1)nf (n = 5-8) series. For 6S ... [more ▼]

Time-resolved laser-induced fluorescence measurements have been performed for ten odd Rydberg states of neutral lutetium, belonging to the 6s(2)(S-1)np(n = 8-9) and 6 s(2)(S-1)nf (n = 5-8) series. For 6S(2)(S-1)8p and 6s(2)(S-1)7f, the experimental lifetimes corresponding to the two J values within the doublet differ substantially. Comparison with theoretical values, calculated with extensive configuration interaction and core-polarization effects included, shows that the experimental trends are adequately reproduced both for np (n = 8-9) and nf (n = 5-8) states. [less ▲]

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See detailProduction of a high percentage of male offspring with a natural androgen, 11 beta-hydroxyandrostenedione (11 beta OHA4), in Florida red tilapia
Desprez, D.; Geraz, E.; Hoarea, M. C. et al

in Aquaculture (2003), 216(1-4), 55-65

This paper reports the effects of a natural androgen, 11beta-hydroxyandrostenedione (11betaOHA4), on sex-reversed fry of the Florida red tilapia. In a first approach, the optimal dosage and duration were ... [more ▼]

This paper reports the effects of a natural androgen, 11beta-hydroxyandrostenedione (11betaOHA4), on sex-reversed fry of the Florida red tilapia. In a first approach, the optimal dosage and duration were determined in the laboratory. The sex-reversal treatment was applied on post-yolksac stage fry (10 days after fertilisation at 27degreesC. Dosages of 20, 30, 40 and 50 mg of 11betaOHA4 kg(-1) of food were used during periods ranging from 10 to 35 days. Dosages of 40 or 50 mg of 11betaOHA4 kg(-1) of food during 21-35 days significantly increased the male percentage in sex-reversed groups in comparison to control groups. A lower but still significant deviation of the male percentage was observed when a dosage of 40 mg kg-1 was given during at least 28 days. Lower dosages did not significantly affect the sex ratio of treated groups. Based on the results of these observations, a follow-up study was conducted to evaluate the efficiency of this natural androgen for an intensive production of sex-reversed fry. Optimal dosage (50 mg kg-1) and treatment duration (28 days) were applied to increasing stocking density of fry (8000-11,000 fish m(-2)), producing a mean male percentage of 99.1% on the 510,000 treated fry. This study demonstrates the masculinizing efficiency of 11betaOHA4 in Florida red tilapia. Interest of a natural androgen, used in sex-reversal treatment, is discussed, particularly for the Florida red tilapia strain. (C) 2003 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailDescription et modélisation de la croissance et du développement du pommier (Malus x domestica Borkh.) : II. Caractéristiques et distribution spatiale et temporelle des sites de floraison.
Planchon, Viviane; Claustriaux, Jean-Jacques ULiege; Crabbé, Jacques

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2003), 7(2), 99-110

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See detailDescription et modélisation de la croissance et du développement du pommier (Malus x domestica Borkh.) : I. Structure la plus probable de l'arbre jeune
Planchon, Viviane; Claustriaux, Jean-Jacques ULiege; Crabbé, Jacques

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2003), 7(1), 37-49

Growth and development of young apple trees are described and modeled from four years of observations.

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See detailEffects of rhein on human articular chondrocytes in alginate beads
Sanchez, Christelle ULiege; Mathy-Hartert, Marianne; Deberg, Michelle ULiege et al

in Biochemical Pharmacology (2003), 65(3), 377-388

This study was designed to investigate the effects of them, the active metabolite of diacerhein, on the metabolic functions of human chondrocytes cultured in alginate beads. Enzymatically isolated ... [more ▼]

This study was designed to investigate the effects of them, the active metabolite of diacerhein, on the metabolic functions of human chondrocytes cultured in alginate beads. Enzymatically isolated ostcoarthritic (OA) chondrocytes were cultured in alginate beads in a well-defined culture medium for 12 days. Rhein was tested in a range of concentrations comprised between 10(-7) and 4 x 10(-5) M, in the presence or absence of 10(-10) M IL-1beta. Interleukin (IL)-6 and -8, macrophage inflammatory protein (MIP-1beta), stromelysin-1 (MMP-3), aggrecan (AGG), tissue inhibitor of metalloproteinases-1 (TIMP-1), prostaglandin E-2 (PGE(2)) and nitric oxide (NO) productions were assayed. Cyclooxygenase-2 (COX-2) and inducible NO synthase (iNOS) mRNA steady-state levels were also quantified. In the basal condition, 10(-5) M them increased by 46.5% the production of AGG, decreased by 17-30% the production of IL-6, MMP-3, NO and MIP-1beta but enhanced by 50% the production of PGE2(.) IL-1beta increased IL-6, IL-8, MIP-1beta, NO, PGE(2) and MMP-3 productions, but inhibited AGG and TIMP-1 synthesis. Rhein partially reversed the effect of IL-1beta on TIMP-1 and NO production, had no effect on AGG, IL-6 and MIP-1P production, but upregulated the IL-1beta stimulated PGE(2) production. The COX-2 and iNOS mRNA levels and IL-8 production were not modified by rhein. Overall, these results contribute to explain the clinical efficiency of rhein and give new information on its mechanisms of action. (C) 2002 Elsevier Science Inc. All rights reserved. [less ▲]

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See detailA new version of the moment method, optimized for mode identification in multiperiodic stars
Briquet, Maryline ULiege; Aerts, C.

in Astronomy and Astrophysics (2003), 398

We present a numerical version of the moment method for the identification of non-radial pulsation modes. The new version requires less computation time than the previous one, allowing users to consider ... [more ▼]

We present a numerical version of the moment method for the identification of non-radial pulsation modes. The new version requires less computation time than the previous one, allowing users to consider all the information contained in the first three moments of a multiperiodic star and to identify multiple modes simultaneously. This, together with the use of a new discriminant that considers the moments calculated at each time of observation, increases considerably the feasibility and the accuracy of the mode identification for multiperiodic stars. Moreover, the technique is extended to rotating pulsating stars. We apply the new version to three B stars showing multiperiodicity. Computer code for mode identification available upon request. Tables 1 to 8 are only available in electronic form at http://www.edpsciences.org [less ▲]

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See detailObservation of dayside subauroral proton flashes with the IMAGE-FUV imagers
Hubert, Benoît ULiege; Gérard, Jean-Claude ULiege; Fuselier, S. A. et al

in Geophysical Research Letters (2003), 30

A detailed description of an intense flash of auroral emissions that occurs equatorward of the dayside auroral oval observed with the IMAGE-FUV imagers is presented. The comparison of simultaneous ... [more ▼]

A detailed description of an intense flash of auroral emissions that occurs equatorward of the dayside auroral oval observed with the IMAGE-FUV imagers is presented. The comparison of simultaneous snapshots of this subauroral flash obtained with the three FUV cameras indicates that proton precipitation is dominant. This transient proton aurora is triggered by the sudden increase of a solar wind dynamic pressure pulse. It occurs on closed field lines mapping to the equatorial plane at distances as small as ~4 R[SUB]E[/SUB]. A second similar event is presented, and several other cases are mentioned. These shock induced transcient emissions develop with a time scale of a few minutes (typically ~5 min), and have a relaxation time on the order of ~10 minutes. [less ▲]

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See detailSpectroscopic mode identification for the beta Cephei star EN (16) Lacertae
Aerts, C.; Lehmann, H.; Briquet, Maryline ULiege et al

in Astronomy and Astrophysics (2003), 399

We perform for the first time spectroscopic mode identification in the eclipsing binary beta Cephei star EN (16) Lac. This mode identification is based upon a time series of 942 line profiles of the He I ... [more ▼]

We perform for the first time spectroscopic mode identification in the eclipsing binary beta Cephei star EN (16) Lac. This mode identification is based upon a time series of 942 line profiles of the He I lambda lambda 6678 Åline in its spectrum. All three known frequencies f[SUB]1[/SUB], f,SUB>2,/SUB>, f[SUB]3[/SUB] of the star are present in the line-profile variations, but we failed to find additional modes. Using different identification methods we find conclusive evidence for the radial nature of the main mode and for the l=2, m=0 identification of the mode with frequency f[SUB]2[/SUB]. A unique identification of the third mode is not possible from the spectra, but we do derive that l[SUB]3[/SUB]<3. Fits to the amplitude and phase variability of the modes imply a rotation frequency between 0.1 and 0.4 c d[SUP]-1[/SUP]. The star's rotation axis is not aligned with the orbital axis. Based on observations gathered with the coudé spectrograph attached to the 2.0 m reflector telescope at Tautenburg Observatory. [less ▲]

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See detailA photometric mode identification method, including an improved non-adiabatic treatment of the atmosphere
Dupret, Marc-Antoine ULiege; De Ridder, J.; De Cat, P. et al

in Astronomy and Astrophysics (2003), 398

We present an improved version of the method of photometric mode identification of Heynderickx et al. (\cite{hey}). Our new version is based on the inclusion of precise non-adiabatic eigenfunctions ... [more ▼]

We present an improved version of the method of photometric mode identification of Heynderickx et al. (\cite{hey}). Our new version is based on the inclusion of precise non-adiabatic eigenfunctions determined in the outer stellar atmosphere according to the formalism recently proposed by Dupret et al. (\cite{dup}). Our improved photometric mode identification technique is therefore no longer dependent on ad hoc parameters for the non-adiabatic effects. It contains the complete physical conditions of the outer atmosphere of the star, provided that rotation does not play a key role. We apply our method to the two slowly pulsating B stars HD 74560 and HD 138764 and to the beta Cephei star EN (16) Lac. Besides identifying the degree l of the pulsating stars, our method is also a tool for improving the knowledge of stellar interiors and atmospheres, by imposing constraints on parameters such as the metallicity and the mixing-length parameter alpha (a procedure we label non-adiabatic asteroseismology). The non-adiabatic eigenfunctions needed for the mode identification are available upon request from the authors. [less ▲]

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See detailMorphological study of magnesium hydroxide nanoparticles precipitated in dilute aqueous solution
Henrist, Catherine ULiege; Mathieu, J. P.; Vogels, C. et al

in Journal of Crystal Growth (2003), 249(1-2), 321-330

Among other applications, magnesium hydroxide is commonly used as a flame-retardant filler in composite materials, as well as a precursor for magnesium oxide refractory ceramic. The microstructure of the ... [more ▼]

Among other applications, magnesium hydroxide is commonly used as a flame-retardant filler in composite materials, as well as a precursor for magnesium oxide refractory ceramic. The microstructure of the powder is of prime importance in both technical applications. The influence of synthesis parameters on the morphological characteristics of magnesium hydroxide nanoparticles precipitated in dilute aqueous medium was studied. Several parameters were envisaged such as chemical nature of the base precipitant, type of counter-ion, temperature and hydrothermal treatment. Special attention was given to the obtaining of platelet-shaped, nanometric and de-agglomerated powders. The powders were characterized in terms of particle size distribution, crystal habits, morphology and ability to be redispersed in water. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption and laser diffusion analyses were used for this purpose. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailEnde einer Odyssee : Zur kritischen Edition der Lyrik Gertrud Kolmars
Viehöver, Vera ULiege

in IASL Online (2003)

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See detailRadiative lifetime and oscillator strength determinations in SmIII
Biémont, Emile ULiege; Garnir, Henri-Pierre ULiege; Litzen, U. et al

in Astronomy and Astrophysics (2003), 399(1), 343-349

Radiative lifetimes of 6 levels belonging to the 4f(5)((6)Hdegrees, (6)Fdegrees)5d configuration of Sm III have been measured for the first time using a time-resolved laser-induced fluorescence technique ... [more ▼]

Radiative lifetimes of 6 levels belonging to the 4f(5)((6)Hdegrees, (6)Fdegrees)5d configuration of Sm III have been measured for the first time using a time-resolved laser-induced fluorescence technique. Experimental data have been compared with semi-empirical calculations. The agreement is excellent for 4 levels with (6)Fdegrees as a parent term. Larger discrepancies (53 and 37%) are observed for 2 levels with (6)Hdegrees and (6)Fdegrees, respectively, as a parent term and are explainable by strong mixing and cancellation effects occurring in the line strength calculations which are responsible of "instabilities" occurring in the lifetimes considered as a function of J value within the term. Branching ratios for the lines depopulating the levels of interest have been measured by Fourier transform spectroscopy. A first set of oscillator strengths has been deduced for this ion. [less ▲]

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See detail"Dermato-couture": points de suture utiles en chirurgie dermatologique
Jacquemin, Gael; Richert, Bertrand ULiege; de LA BRASSINNE, Michel ULiege

in Revue Médicale de Liège (2003), 58(2), 88-94

Dermatologists performing skin surgery mostly use the square knot. Other underused or even forgotten suturing techniques may still be helpful in some instances. We shall emphasize some simple techniques ... [more ▼]

Dermatologists performing skin surgery mostly use the square knot. Other underused or even forgotten suturing techniques may still be helpful in some instances. We shall emphasize some simple techniques such as the horizontal mattress suture, the “cross stitch”, the “corner stitch” (half buried mattress suture), the buried dermal suture, the buried vertical mattress suture, the continuous mattress suture and the running intradermal suture. In given circumstances, all of them may improve suturing and promote healing. Technical aspects, advantages and disadvantages of each type of suture will be briefly described. [less ▲]

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See detailStripe patterns in self-stratification experiments
Lecocq, N.; Vandewalle, Nicolas ULiege

in Fractals-Complex Geometry Patterns and Scaling in Nature and Society (2003), 11(Suppl. S), 259-269

We report pattern formation of complex stripes with binary and ternary granular mixtures. Ternary mixtures lead to a particular ordering of the strates which was not accounted for in former explanations ... [more ▼]

We report pattern formation of complex stripes with binary and ternary granular mixtures. Ternary mixtures lead to a particular ordering of the strates which was not accounted for in former explanations. Bouncing grains are found to have an important effect on strate formation. A complementary mechanism for self-stratification of binary and ternary granular mixtures is proposed. This mechanism leads to a simple model. Eventually we report the observation of self-stratification for a binary mixture of grains of the same size but with different shapes. [less ▲]

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See detailTraitement hormonal apres cancer du sein. Oui ... ou non?
Foidart, Jean-Michel ULiege; Desreux, Joëlle ULiege; Lifrange, Eric ULiege et al

in Revue Médicale de Liège (2003), 58(2), 77-82

Clinical and experimental studies indicate that combined unique conjugated estrogens and medroxyprogesterone acetate moderately increase the risk of breast cancer in postmenopausal women. Classically ... [more ▼]

Clinical and experimental studies indicate that combined unique conjugated estrogens and medroxyprogesterone acetate moderately increase the risk of breast cancer in postmenopausal women. Classically, hormone replacement therapy is contra-indicated in women with a past history of breast cancer due to the fear of recurrence. However, these postmenopausal patients complain about hot flushes and adjuvant hormonal therapies (such as aromatase inhibitors, SERMs and Tamoxifen...) aggravate their symptoms. Observational studies and their meta-analyses do not show a deleterious effect but rather a beneficial impact of hormone replacement therapy among women with a past history of breast cancer. We summarise all these studies and their biological, clinical and epidemiological interpretations. We conclude that short term hormone replacement therapy is safe among those women requesting a replacement therapy after complete information. It is however advisable to conclude definitely only when prospective randomised trials with estradiol or tibolone (a promising alternative) will be available. Such ongoing studies will allow to conclude definitely the possible benefits and risks of hormone replacement therapy among patients with a past history of breast cancer. [less ▲]

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See detailis there any rationale for prescribing hormone replacement therapy (HTR) to prevent or to treat osteoarthritis?
Reginster, Jean-Yves ULiege; Kvasz, Angela ULiege; Bruyère, Olivier ULiege et al

in Osteoarthritis and Cartilage (2003), 11(2), 87-91

Background: During the last two decades of the 20th century, hormone replacement therapy (HRT) has been considered as the sole pharmacological approach for counterbalancing or mitigating the effects of ... [more ▼]

Background: During the last two decades of the 20th century, hormone replacement therapy (HRT) has been considered as the sole pharmacological approach for counterbalancing or mitigating the effects of estrogens deprivation in post-menopausal women. Subsequently, HRT has been widely recommended for the management of chronic diseases occurring, in women during the second half of their life. The overall risk/benefit ratio of estrogens has been recently reassessed in the light of long-term prospective studies failing to demonstrate the expected benefit of HRT on cardiovascular diseases incidence. Osteoarthritis (OA) is one of the chronic conditions for which HRT has been suggested to provide beneficial outcomes. Results: The presence of estrogen receptors in human cartilage is no longer debated. However, cellular or animal models of OA do not provide an unequivocal pathway for the influence of gonadal steroids on cartilage. Similarly, studies attempting to correlate serum or urinary levels of sex steroids to the onset or progression of OA gave conflicting results. No randomized, prospective, controlled trial was designed to specifically assess the impact of hormone replacement therapy on symptomatic or structural progression of OA. Large-scale observational studies or trials designed to assess other potential benefits of estrogens suggest that HRT use does not provide symptomatic relief in OA but may interfere with its long-term structural progression, particularly in the lower limbs. Conclusion: Based on the recent results of the Women Health Initiative suggesting that HRT health risks may outweigh benefits, one can hardly recommend, with the current level of evidence, HRT as a first-line treatment against progression of OA. (C) 2003 OsteoArthritis Research Society International. Published by Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailLire ou ne pas lire : état de la question
Baye, Ariane ULiege; Lafontaine, Dominique ULiege; Vanhulle, Sabine

in Cahiers du Centre de Lecture publique de la Communauté française (2003), 4

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See detailLong-term efficacy of risedronate: a 5-year placebo-controlled clinical experience
Sorensen, O. H.; Crawford, G. M.; Mulder, H. et al

in BONE (2003), 32(2), 120-126

Limited placebo-controlled data are available to assess the long-term fracture efficacy of bisphosphonates. In order to determine the effects of 5 years of risedronate treatment, we extended a 3-year ... [more ▼]

Limited placebo-controlled data are available to assess the long-term fracture efficacy of bisphosphonates. In order to determine the effects of 5 years of risedronate treatment, we extended a 3-year, placebo-controlled vertebral fracture study in osteoporotic women for an additional 2 years; women who entered the extension study continued to receive 5 mg risedronate or placebo according to the original randomization, with maintenance of blinding. End points included vertebral and nonvertebral fracture assessments, bone mineral density measurements, and changes in biochemical markers of bone turnover. A total of 265 women (placebo, 130; 5 mg risedronate, 135) entered the study extension and 220 (83%) completed the additional 2 years. Fracture results observed in the study extension were consistent with those observed in the first 3 years. The risk of new vertebral fractures was significantly reduced with risedronate treatment in years 4 and 5 by 59% (95% confidence interval, 19 to 79%, P = 0.01) compared with a 49% reduction in the first 3 years. Rapid and significant decreases in markers of bone turnover observed in the first 3 years were similarly maintained in the next 2 years of treatment. Increases in spine and hip bone mineral density that occurred in the risedronate group during the first 3 years were maintained or increased with a further 2 years of treatment. The mean increase from baseline in lumbar spine BMD over 5 years was 9.3% (P < 0.001). This study demonstrates that the effects of risedronate over 3 years on vertebral fracture and BMD are maintained with a further 2 years of treatment. (C) 2003 Elsevier Science (USA). All rights reserved. [less ▲]

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See detailStrontium ranelate: A new paradigm in the treatment of osteoporosis
Reginster, Jean-Yves ULiege; Deroisy, Rita ULiege; Jupsin, Isabelle ULiege

in Drugs of Today (2003), 39(2), 89-101

Not one of the currently available medications has, so far, unequivocally demonstrated its ability to fully prevent the occurrence of new vertebral or peripheral osteoporotic fractures once osteoporosis ... [more ▼]

Not one of the currently available medications has, so far, unequivocally demonstrated its ability to fully prevent the occurrence of new vertebral or peripheral osteoporotic fractures once osteoporosis is established. Therefore, several new therapies are currently under development to optimize the risk/benefit ratio of osteoporosis treatment. Strontium ranelate is composed of an organic moiety (ranelic acid) and of two atoms of stable nonradioactive strontium. In vitro, strontium ranelate increases Collagen and noncollagenic proteins synthesis by mature osteoblast enriched cells. The effects of strontium ranelate on bone formation were confirmed as strontium ranelate enhanced pre-osteoblastic cell replication. The stimulation by strontium ranelate of the replication of osteoprogenitor cell and collagen, as well as noncollagenic protein synthesis in osteoblasts, provides substantial evidence to categorize strontium ranelate as a bone-forming agent. In the isolated rat osteoclast assay, a pre-incubation of bone slices with strontium ranelate induced a dose-dependent inhibition of the bone resorbing activity of treated rat osteoclast. Strontium ranelate also dose-dependently inhibited, in a chicken bone marrow culture, the expression of both carbonic anhydrase 11 and the (x-subunit of the vitronectin receptor. These effects showing that strontium ranelate significantly affects bone resorption due to a direct and/or matrix-mediated inhibition of osteoclast activity and also inhibits osteoclasts differentiation, are compatible with the profile of an anti-resorptive drug. In normal rats, administration of strontium ranelate induces an improvement in the mechanical properties of the humerus and/or the lumbar vertebra associated with a commensurate increase in bone dimension, shaft and volume. Strontium ranelate was administered in 160 early postmenopausal women, in a 24-month, double-blind, placebo-controlled, prospective randomized study. Daily oral dose of 125 mg, 500 mg and 1 g of strontium ranelate were compared with a placebo. At the conclusion of the study, the percent variation of lumbar-adjusted bone mineral density from baseline was significantly different in the group receiving 1 g/day of strontium ranelate compared with placebo (+1.41% vs. -0.98%, respectively). Increase in total hip and neck bone mineral density averages, respectively, 3.2% and 2.5%. Strontium ranelate does not induce any significant adverse reaction compared with those observed in women receiving a placebo for the same duration. In a phase 11 study, the effect of strontium ranelate in postmenopausal women with vertebral osteoporotic fractures was assessed during a double-blind, placebo-controlled trial. Doses of 500 mg, 1 g and 2 g daily of strontium ranelate or placebo were given to 353 Caucasian women with prevalent osteoporosis. At the conclusion of this 2-year study, the annual increase in lumbar-adjusted bone mineral density of the group receiving 2 g of strontium ranelate was +2.97%. This result was significantly different compared with placebo. A significant increase in bone alkaline phosphatase and, over a 6-month period, a significant decrease in urinary-pyridium crosslinks (NTX) were evidenced. During the second year of treatment, the dose of 2 g was associated with a 44% reduction in the number of patients experiencing a new vertebral deformity. Bone histomorphometry showed no mineralization defects. The same percentage of withdrawals following an adverse effect was observed for patients receiving placebo and for those receiving 2 g of strontium ranelate. The compound was further investigated in a large phase III program that included two extensive trials for the treatment of severe osteoporosis, one assessing the effects of strontium ranelate on the risk of vertebral fractures (SOTI) and one evaluating its effects on peripheral (nonspinal) fractures (TROPOS). The primary analysis of the SOTI study, evaluating the effect of 2 g of strontium ranelate on vertebral fracture rates, revealed a 41% reduction in the relative risk of experiencing a first new vertebral fracture with strontium ranelate, throughout the 3-year study, compared with placebo. The TROPOS study, showed a significant (p = 0.05) reduction in the relative risk of experiencing a first non-vertebral fracture in the group treated with strontium ranelate throughout the 3-year study compared with placebo in the intention-to-treat population. A 41% reduction in the relative risk of experiencing a hip fracture was demonstrated in the per protocol population. All these results imply that strontium ranelate is a new, effective and safe treatment for vertebral and nonvertebral osteoporosis, with a unique mode of action. (C) 2003 Prous Science. All rights reserved. [less ▲]

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See detailPatient assessment using standardized bone mineral density values and a national reference database: implementing uniform thresholds for the reimbursement of osteoporosis treatments in Belgium
Boonen, S.; Kaufman, J. M.; Reginster, Jean-Yves ULiege et al

in Osteoporosis International (2003), 14(2), 110-115

Dual-energy X-ray absorptiometry (DXA) devices from the three main manufacturers provide different bone mineral density (BMD) values, due in part to technical differences in the algorithms for bone ... [more ▼]

Dual-energy X-ray absorptiometry (DXA) devices from the three main manufacturers provide different bone mineral density (BMD) values, due in part to technical differences in the algorithms for bone mineral content (BMC) and area measurements and in part to the use of different manufacturer-derived reference databases. As a result, significant differences exist between Hologic, Lunar and Norland systems in the reported young normal standard deviation scores or T-scores. In a number of European countries, including Belgium, a T-score below -2.5 is one of the key criteria for reimbursement of osteoporosis treatments. This paper addresses the first attempt to implement a nationwide, uniform expression of BMD in patients, in order to harmonize drug reimbursement. To this end, measures were taken to implement a uniform expression of BMD in Belgian patients, by converting each manufacturer's absolute BMD to standardized BMD (sBMD) values and by establishing a single national reference range. [less ▲]

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See detailFamily size and optimal income taxation
Cremer, Helmuth; Dellis, Arnaud; Pestieau, Pierre ULiege

in Journal of Population Economics (2003), 16(1), 37-54

This paper studies the role of family size in the design of optimal income taxation. We consider a second best setting where the government observes the number of children and the income of the parents ... [more ▼]

This paper studies the role of family size in the design of optimal income taxation. We consider a second best setting where the government observes the number of children and the income of the parents but not their productivity. With a linear tax schedule the marginal tax rate is shown to decrease with the number of children, while the relationship between the demogrant and family size appears to be ambiguous. With two ability levels, optimal non-linear income tax implies zero marginal tax rates for the higher ability parents; low ability parents have positive marginal tax rates that decrease with family size. [less ▲]

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See detailSpät erst erfahren Sie sich Judith Hermann findet "Nichts als Gespenster"
Pontzen, Alexandra ULiege

in Literaturkritik.de (2003)

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See detailDeficiency of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) impairs nutritionally induced obesity in mice.
Lijnen, Roger; Demeulemeester, Diego; Van Hoef, B. et al

in Thrombosis and Haemostasis (2003), 89(2), 249-255

Tissue inhibitor of matrix metalloproteinase-1 deficient (TIMP-1(-/-)) mice and wild-type (TIMP-1(+/+)) controls were kept on a standard (SFD) or a high fat diet (HFD) for 15 weeks. At the time of ... [more ▼]

Tissue inhibitor of matrix metalloproteinase-1 deficient (TIMP-1(-/-)) mice and wild-type (TIMP-1(+/+)) controls were kept on a standard (SFD) or a high fat diet (HFD) for 15 weeks. At the time of sacrifice, TIMP-1(-/-) mice on HFD had a significantly lower body weight (29 +/- 1.5 versus 41 +/- 1.8 g, p <0.005), and significantly less subcutaneous (0.81 +/- 0.19 versus 1.78 +/- 0.21 g, p <0.05) and gonadal (0.87 +/- 0.17 versus 1.85 +/- 0.18 g, p <0.005) fat mass. These differences were much less pronounced for mice on SFD. On HFD but not on SFD, adipocyte diameters were significantly lower in the adipose tissue of TIMP-1(-/-) mice. Plasma leptin levels in TIMP-1(-/-) mice on HFD were significantly lower as compared to TIMP-1(+/-) mice, and strongly correlated with adipose tissue mass for both genotypes. Staining with an endothelial cell specific lectin revealed a significantly higher blood vessel density, larger stained area and vessel size in adipose tissue of TIMP-1(-/-) mice on HFD. This difference disappeared after normalization to the adipocyte number, suggesting that it does not represent a true enhancement of angiogenesis. Thus, in a murine model of nutritionally induced obesity, TIMP-1 promotes adipose tissue development. [less ▲]

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See detailMineralogical gradients associated with alvinellids at deep-sea hydrothermal vents
Zbinden, M.; Le Bris, N.; Compère, Philippe ULiege et al

in Deep-Sea Research Part I-Oceanographic Research Papers (2003), 50(2), 269-280

Alvinella pompejana and Alvinella caudata live in organic tubes on active sulphide chimney walls at deep-sea hydrothermal vents. These polychaete annelids are exposed to extreme thermal and chemical ... [more ▼]

Alvinella pompejana and Alvinella caudata live in organic tubes on active sulphide chimney walls at deep-sea hydrothermal vents. These polychaete annelids are exposed to extreme thermal and chemical gradients and to intense mineral precipitation. This work points out that mineral particles associated with Pompeii worm (A. pompejana and A. caudata) tubes constitute useful markers for evaluating the chemical characteristics of their micro-environment. The minerals associated with these worm tubes were analysed on samples recovered from an experimental alvinellid colony, at different locations in the vent fluid-seawater interface. Inhabited tubes from the most upper and lower parts of the colony were analysed by light and electron microscopies, X-ray microanalysis and X-ray diffraction. A change was observed from a Fe-Zn-S mineral assemblage to a Zn-S assemblage at the millimeter scale from the outer to the inner face of a tube. A similar gradient in proportions of minerals was observed at a decimeter scale from the lower to the upper part of the colony. The marcasitc/pyrite ratio of iron disulphides also displays a steep decrease along the few millimeters adjacent to the external tube surface. The occurrence of these gradients indicates that the microenvironment within the tube differs from that outside the tube, and suggests that the tube wall acts as an efficient barrier to the external environment. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailOn functional and structural heterogeneity of VIM-type metallo-beta-lactamases
Docquier, J. D.; Lamotte-Brasseur, J.; Galleni, Moreno ULiege et al

in Journal of Antimicrobial Chemotherapy (2003), 51(2), 257-266

The VIM metallo-beta-lactamases are emerging resistance determinants, encoded by mobile genetic elements, that have recently been detected in multidrug-resistant nosocomial isolates of Pseudomonas ... [more ▼]

The VIM metallo-beta-lactamases are emerging resistance determinants, encoded by mobile genetic elements, that have recently been detected in multidrug-resistant nosocomial isolates of Pseudomonas aeruginosa and other Gram-negative pathogens. In this work a T7-based expression system for overproduction of the VIM-2 enzyme by Escherichia coli was developed, which yielded similar to80 mg of protein per litre of culture. The enzyme was mostly released into the medium, from which it was recovered at >99% purity by an initial ammonium sulphate precipitation followed by two chromatography steps, with almost 80% efficiency. Determination of kinetic parameters of VIM-2 under the same experimental conditions previously used for VIM-1 (the first VIM-type enzyme detected in clinical isolates, which is 93% identical to VIM-2) revealed significant differences in K-m values and/or turnover rates with several substrates, including penicillins, cephalosporins and carbapenems. Compared with VIM-1, VIM-2 is more susceptible to inactivation by chelators, indicating that the zinc ions of the latter are probably more loosely bound. These data indicated that at least some of the amino acid differences between the two proteins have functional significance. Molecular modelling of the two enzymes identified some amino acid substitutions, including those at positions 223, 224 and 228 (in the BBL numbering), that could be relevant to the changes in catalytic behaviour. [less ▲]

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See detailIndolomonoterpenic alkaloids from Strychnos icaja roots
Philippe, Geneviève ULiege; De Mol, Patrick ULiege; Zeches-Hanrot, M. et al

in Phytochemistry (2003), 62(4), 623-629

In the course of our search for new antiplasmodial alkaloids from Strychnos icaja, we have isolated five alkaloids: three monomers, protostrychnine and genostrychnine, previously described in Strychnos ... [more ▼]

In the course of our search for new antiplasmodial alkaloids from Strychnos icaja, we have isolated five alkaloids: three monomers, protostrychnine and genostrychnine, previously described in Strychnos nux-vomica, pseudostrychnine, already found in the leaves of the plant, a new bisindolic alkaloid, named strychnogucine C, and the first naturally occurring trimeric indolomonoterpenic alkaloid: strychnohexamine. This latter trimeric alkaloid presented an antiplasmodial activity against the FCA Plasmodium falciparum line near I muM. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailResults of exercise testing at a mean age of 10 years after neonatal arterial switch operation.
Hovels-Gurich, H. H.; Kunz, D.; Seghaye, Marie-Christine ULiege et al

in Acta paediatrica (Oslo, Norway : 1992) (2003), 92(2), 190-6

AIM: This prospective follow-up study investigated long-term exercise capacity at a mean age of 10 y after neonatal arterial switch operation for transposition of the great arteries in a large group of ... [more ▼]

AIM: This prospective follow-up study investigated long-term exercise capacity at a mean age of 10 y after neonatal arterial switch operation for transposition of the great arteries in a large group of homogeneous unselected children. METHODS: 56 asymptomatic children, aged 7.9-14.3 y (10.5 +/- 1.6, mean +/- SD), were examined with respect to exercise tolerance, electrocardiographic (ECG) response and activity of biochemical markers for myocardial injury. The protocol included standard electrocardiography, M-mode and two-dimensional echocardiography at rest, a Bruce walking treadmill test to voluntary exhaustion, and determination of cardiac troponin I and T, creatine kinase and myoglobin from venous blood samples at rest and 4 h after exercise. Heart rate, blood-pressure response to exercise stress and endurance time were compared with published results of age-matched normal children. RESULTS: 54 patients (96.4%) had normal exercise capacity; a reduction in 2 patients was not due to cardiac disease. Heart rate and systolic blood pressure rose significantly between rest and peak exercise and did not differ from normal controls, whereas diastolic blood pressure was lower. ECG remained normal at rest and on exercise in 54 children (96.4%). Serum values of cardiac troponin I and T, creatine kinase and myoglobin were normal at rest and after exercise in all patients. CONCLUSION: The study demonstrates excellent long-term exercise capacity after neonatal arterial switch operation. Exercise testing is a useful and non-invasive screening method to detect patients with clinically relevant exercise-induced myocardial ischaemia and should be routinely performed in growing patients. [less ▲]

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See detailA new proposal of a simple model for the lateral-torsional buckling of unrestrained steel I-beams in case of fire: experimental and numerical validation
Vila Real, Paolo; Piloto, Paolo; Franssen, Jean-Marc ULiege

in Journal of Constructional Steel Research (2003), 59(2), 179-199

The behaviour of Steel I-Beams exhibiting lateral-torsional buckling at elevated temperature has been studied by means of experimental and numerical analysis. The authors in an earlier paper have ... [more ▼]

The behaviour of Steel I-Beams exhibiting lateral-torsional buckling at elevated temperature has been studied by means of experimental and numerical analysis. The authors in an earlier paper have presented an analytical formula for the buckling resistance moment in the fire design situation. This new proposal, different from the actual proposal of the Eurocode 3 Part 1.2 has been validated in this work by comparison with the results from a set of 120 experimental and numerical tests performed on IPE 100 beams, submitted to temperatures varying from room temperature to 600 degreesC. The numerical simulations have been based on the measured geometrical dimensions of the cross-sections, the longitudinal imperfections, i.e. the out of straightness of the beams, the residual stresses and the yield strength. The Eurocode simple model promotes ultimate loads that depend mainly on the non-dimensional slenderness of the beams. The analytical results provided by the Eurocode 3, for a certain range of the slenderness, appear to be unsafe when compared with the numerical and experimental results. It is shown that the new proposal is safer than the Eurocode 3 formulas. (C) 2002 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailA seroepidemiological study of human cysticercosis in West Cameroon
Nguekam, J. P.; Zoli, A. P.; Zogo, P. O. et al

in Tropical Medicine & International Health [=TM & IH] (2003), 8(2), 144-149

We studied the occurrence of human cysticercosis in 4993 individuals from three rural communities of Menoua Division, West Province of Cameroon. Circulating antigens of Taenia solium metacestodes were ... [more ▼]

We studied the occurrence of human cysticercosis in 4993 individuals from three rural communities of Menoua Division, West Province of Cameroon. Circulating antigens of Taenia solium metacestodes were detected in 0.4%, 1.0% and 3.0% of the serum samples taken in Bafou, Bamendou and Fonakekeu, respectively, and examined using a monoclonal antibody-based enzyme-linked immunosorbent assay. This test detects only carriers of living cysticerci and gives thus a good idea of the presence of Active cysticercosis. The percentage of persons infected with cysticercosis increased with age. Twenty-two of the 34 seropositives underwent computed tomography (CT) of the brain. Thirteen of them were CT-scan positive, which shows that neurocysticercosis was present in 59.1% of the tested seropositive persons. No living cysticerci were detected among 20 seronegative people. About 20.6% of the seropositives had a history of or current taeniasis against only 1.9% of the seronegatives. Based on these figures and on the data on porcine cysticercosis (prevalence: 11%) and human taeniasis (prevalence: 0.13%) collected in the same region, we conclude that T. solium cysticercosis is an endemic, but overlooked public health problem in West Cameroon. [less ▲]

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See detailLine profile variability in the spectra of Oef stars. I. BD + 60deg 2522
Rauw, Grégor ULiege; De Becker, Michaël ULiege; Vreux, Jean-Marie ULiege

in Astronomy and Astrophysics (2003), 399

We report the analysis of a long term observing campaign designed to monitor the spectroscopic variability of the Oef star BD +60deg 2522. We find that the double-peaked He {II} lambda 4686 emission line ... [more ▼]

We report the analysis of a long term observing campaign designed to monitor the spectroscopic variability of the Oef star BD +60deg 2522. We find that the double-peaked He {II} lambda 4686 emission line undergoes strong profile variability on time scales of 2-3 day. However, the time scale as well as the pattern of these variations turn out to be epoch dependent and the phenomenon is thus most likely not ruled by a single stable clock. On the other hand, the absorption lines in the spectrum of BD +60deg 2522 display line profile variability on time scales of a few hours that might be related to non-radial pulsations. We tentatively propose that the beating of several non-radial pulsation modes triggers transient large-scale density perturbations in a confined stellar wind that produce the 2-3 day time scale variability. [less ▲]

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See detailEffect of intra-operative magnesium sulphate on pain relief and patient comfort after major lumbar orthopaedic surgery
Levaux, Christine ULiege; Bonhomme, Vincent ULiege; Dewandre, Pierre-Yves et al

in Anaesthesia (2003), 58(2), 131-135

The effects of intra-operative magnesium sulphate on pain relief after major lumbar surgery were investigated in 24 patients. Patients were randomly allocated to receive either an infusion of 50 mg x kg ... [more ▼]

The effects of intra-operative magnesium sulphate on pain relief after major lumbar surgery were investigated in 24 patients. Patients were randomly allocated to receive either an infusion of 50 mg x kg(-1) magnesium sulphate or an equivalent volume of saline at induction of anaesthesia. Anaesthesia was induced with propofol and remifentanil. Tracheal intubation was facilitated using rocuronium. Maintenance was achieved with remifentanil and sevoflurane in nitrous oxide/ oxygen. Intra-operative monitoring included standard equipment and neuromuscular transmission. During surgery, neuromuscular block recovery was longer in the magnesium group. Postoperative opioid consumption and pain scores were lower in the magnesium group. The first night's sleep and the global satisfaction scores were better in the magnesium group. The results of the study support magnesium sulphate as a useful adjuvant for postoperative analgesia after major lumbar surgery. [less ▲]

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See detailLa mesure du débit de filtration glomérulaire en clinique quotidienne
Delanaye, Pierre ULiege; Chapelle, Jean-Paul ULiege; Ferir, Anne-Marie et al

in Revue Médicale de Liège (2003), 58(2), 95-100

Glomerular filtration rate (GFR) is the most frequently used parameter to evaluate the renal function. GFR may be estimated with serum creatinine, creatinine clearance based on 24 hours urine collection ... [more ▼]

Glomerular filtration rate (GFR) is the most frequently used parameter to evaluate the renal function. GFR may be estimated with serum creatinine, creatinine clearance based on 24 hours urine collection or Cockcroft formula. All these methods have bias. Other approaches have thus been proposed. The limitations and advantages of isotopic methods and recent mathematical approaches (MDRD formula) are reviewed. [less ▲]

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See detailDetermination of polyisoprene-block-poly(methyl methacrylate) domain sizes using 1H spin diffusion
Werkhoven, Thekla M; Mulder, Fokko M; Zune, Catherine et al

in Macromolecular Chemistry and Physics (2003), 204(1), 46-51

The microphase structure of polyisoprene-block-poly(methyl methacrylate) diblock copolymers was studied using solid-state NMR techniques. Wideline separation spectroscopy reveals a narrow interphase ... [more ▼]

The microphase structure of polyisoprene-block-poly(methyl methacrylate) diblock copolymers was studied using solid-state NMR techniques. Wideline separation spectroscopy reveals a narrow interphase between the two polymers. The domain sizes of a lamellar sample and a sample with hexagonally ordered cylinders were determined using 1H spin diffusion. The lamellar sample shows a domain size of 16 ± 2 nm for the minor polyisoprene phase and a long period of 33 ± 4 nm. The cylindrical structure has a long period of 38 ± 7 nm, the diameter of the PMMA cylinders is 21 ± 4 nm. These results are about 20% below the estimates obtained from theoretical calculations according to Helfand and Wasserman [less ▲]

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See detailThree-dimensional structure of FEZ-1, a monomeric subclass B3 metallo-beta-lactamase from Fluoribacter gormanii, in native form and in complex with D-captopril
Garcia-Saez, I.; Mercuri, Paola ULiege; Papamicael, C. et al

in Journal of Molecular Biology (2003), 325(4), 651-660

The beta-lactamases are involved in bacterial resistance to penicillin and related compounds. Members of the metallo-enzyme class are now found in many pathogenic bacteria and are thus becoming of major ... [more ▼]

The beta-lactamases are involved in bacterial resistance to penicillin and related compounds. Members of the metallo-enzyme class are now found in many pathogenic bacteria and are thus becoming of major clinical importance. The structures of the Zn-beta-lactamase from Fluoribacter gormanii (FEZ-1) in the native and in the complex form are reported here. FEZ-I is a monomeric enzyme, which possesses two zinc-binding sites. These structures are discussed in comparison with those of the tetrameric L1 enzyme produced by Stenotrophomonas maltophilia. From this analysis, amino acids involved in the oligomerization of L1 are clearly identified. Despite the similarity in fold, the active site of FEZ-1 was found to be significantly different. Two residues, which were previously implicated in function, are not present in L1 or in FEZ-1. The broad-spectrum substrate profile of Zn-beta-lactamases arises from the rather wide active-site cleft, where various P-lactam compounds can be accommodated. (C) 2003 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailProbing of the reaction progress at a PMMA/PS interface by using anthracene-labeled reactive PS chains
Yin, Zhihui; Koulic, Christian; Pagnoulle, Christophe et al

in Langmuir (2003), 19(2), 453-457

The progress of the interfacial reaction of polystyrene chains end-capped by a primary amine (PS-NH2) and PMMA chains end-capped by an anhydride (PMMA-anh) has been monitored by SEC-UV, by using ... [more ▼]

The progress of the interfacial reaction of polystyrene chains end-capped by a primary amine (PS-NH2) and PMMA chains end-capped by an anhydride (PMMA-anh) has been monitored by SEC-UV, by using anthracene-labeled polystyrene chains (anth-PS-NH2) as a probe. Assemblies of an anth-PS-NH2 layer and a PMMA-anh layer were annealed at 200 degreesC for various periods of time. The interfacial reaction rate depends on the molecular weight (MW) of the reactive precursors in relation to the gammaN value of the chains. For chains of low gammaN (chiN = 6), the reaction is faster because the interface becomes more diffuse with time, as observed by TEM and AFM, consistent with compatibilization of the weakly immiscible polymers by the copolymer formed in-situ. For chains of higher molecular weight and chiN (10, instead of 6), the interface is much sharper and the residence time at the interface of the symmetric diblock copolymer of higher molecular weight is also increased, which dramatically restricts the progress of the interfacial reaction under the annealing conditions used in this work. [less ▲]

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See detailDetermination of uncertainty in analytical measurements from collaborative study results on the analysis of a phenoxymethylpenicillin sample
Dehouck, Pieter; Vander Heyden, Yvan; Smeyers-Verbeke, Johanna et al

in Analytica Chimica Acta (2003), 481

The correct interpretation of a measurement result requires knowledge about its uncertainty. Depending on the conditions under which the analyst is operating, different operational definitions of ... [more ▼]

The correct interpretation of a measurement result requires knowledge about its uncertainty. Depending on the conditions under which the analyst is operating, different operational definitions of uncertainty have been proposed. They include: within-laboratory uncertainty, reproducibility uncertainty, bias-included uncertainty and absolute uncertainty. Here we consider the evaluation of the reproducibility uncertainty derived from the results obtained in an inter-laboratory experiment. Nine laboratories participated in an inter-laboratory study for the analysis of phenoxymethylpenicillin. The analyses consisted of a Karl–Fischer water determination, an acid–base titration to assay phenoxymethylpenicillin and a liquid chromatography (LC) method to determine 4-hydroxyphenoxymethylpenicillin and other impurities. The experimental set-up allowed to obtain for each determination s2 r and s2L as estimates of the repeatability variance (σ2r ) and the between-laboratory variance (σ2L), respectively. The reproducibility uncertainties for the different assays were then derived from these estimates. [less ▲]

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See detailStabilization of a cocontinuous phase morphology by a tapered diblock or triblock copolymer in polystyrene-rich low-density polvethylene/polstyrene blends
Harrats, Charef; Fayt, Roger; Jérôme, Robert ULiege et al

in Journal of Polymer Science. Part B, Polymer Physics (2003), 41(2), 202-216

The stability against the thermal annealing of a cocontinuous two-phase morphology developed in polystyrene (PS)/low-density polyethylene (LDPE) blends containing 80 wt % PS was investigated. Blends ... [more ▼]

The stability against the thermal annealing of a cocontinuous two-phase morphology developed in polystyrene (PS)/low-density polyethylene (LDPE) blends containing 80 wt % PS was investigated. Blends containing 1, 5, and 10 wt % of a tapered diblock poly(styrene-block-hydrogenated butadiene) (P(S-b-hB)) or triblock poly(styrene-block-hydrogenated butadiene-block-styrene) (P(S-hB-S)) copolymer were melt-blended with roll-mill mixing equipment. The efficiency of each of the two copolymers in stabilizing against coalescence the cocontinuous morphology was examined. The tensile properties of the resulting blends, annealed and nonannealed, were also examined in relation to the morphology induced by thermal annealing. The phase morphology was studied by optical and scanning electron microscopy. With computer-aided image analysis, it was possible to obtain a measurable characteristic parameter to quantify the cocontinuous phase morphology. When it was necessary, the extraction of one phase with a selective solvent was performed. Although the observed differences were subtle, the tapered diblock exhibited a more efficient compatibilizing activity than the triblock copolymer, particularly at a low concentration of about 2 wt %. The superiority of the tapered diblock over the triblock might be due to its ability to quantitatively locate at the LDPE/PS interface and consequently form a more efficient barrier against the subsequent breakup of the elongated structures of the cocontinuous phase morphology. The tensile properties of the triblock-modified blends were more sensitive to thermal annealing than the tapered-modified ones. This deficiency was ascribed to the phase morphology coarsening of the dispersed polyethylene phase. [less ▲]

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See detailProperties of molten Ge chalcogenides: an ab initio molecular dynamics study
Raty, Jean-Yves ULiege; Gaspard, Jean-Pierre ULiege; Bichara, C.

in Journal of Physics : Condensed Matter (2003), 15(1 Sp. Iss. SI), 167-173

In this study, we perform first-principles molecular dynamics simulations of the eutectic alloy Ge15Te85 at five different densities and temperatures. We obtain structures in agreement with the available ... [more ▼]

In this study, we perform first-principles molecular dynamics simulations of the eutectic alloy Ge15Te85 at five different densities and temperatures. We obtain structures in agreement with the available diffraction data and obtain a new view of the molten Ge chalcogenides. We show that the anomalous volume contraction observed in the liquid 30 K above the eutectic temperature corresponds to a significant change of the Ge-Te partial structure factor. The detailed structural analysis shows that volume variations observed upon melting in Ge15Te85, as in liquid, GeSe and GeTe, can be explained in terms of the competition between two types of local environment of the germanium atoms. A symmetrical coordination octahedron is entropically favoured at high temperature, while an asymmetrical octahedron resulting from the local manifestation of the Peierls distortion is electronically favoured at lower temperatures. [less ▲]

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See detailAlong or across front survey strategy? An operational example at an unstable front
Rixen, Michel; Allen, J. T.; Alderson, S. et al

in Geophysical Research Letters (2003), 30(1),

[1] We present results of the optimization of near-real time on-board sampling strategy in the Iceland-Faroes oceanic frontal area, based on the outputs of a mesoscale 3D operational data assimilation ... [more ▼]

[1] We present results of the optimization of near-real time on-board sampling strategy in the Iceland-Faroes oceanic frontal area, based on the outputs of a mesoscale 3D operational data assimilation forecasting experiment. By minimizing a root mean square error cost function, we show that in this example an along-front sampling strategy, i.e. with transects parallel to the front, produces smaller errors in temperature, salinity, nitrate, phytoplankton, and zooplankton fields, as a result of a combination of the direction of the sampling of the front and errors associated with the asynopticy of observations (Doppler effect). This is contrary to the classic across-front sampling strategies that are used in most field experiments reported in the literature, i.e. where transects are perpendicular to the front. A control model shows that at these spatio-temporal scales, the along front sampling strategy is optimal when the frontal instability has sufficiently developed. [less ▲]

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See detailSex differences in the distribution of the steroid receptor coactivator SRC-1 in the song control nuclei of male and female canaries
Charlier, Thierry ULiege; Balthazart, Jacques ULiege; Ball, Gregory F

in Brain Research (2003), 959(2), 263-274

The steroid receptor coactivator SRC-1 modulates ligand-dependent transactivation of several nuclear receptors, including the receptors for sex steroid hormones. The distribution of SRC-1 transcripts was ... [more ▼]

The steroid receptor coactivator SRC-1 modulates ligand-dependent transactivation of several nuclear receptors, including the receptors for sex steroid hormones. The distribution of SRC-1 transcripts was analyzed here by in situ hybridization in coronal sections through the brain of male and female canaries. A broad but heterogeneous distribution of SRC-1 transcripts was observed with high numbers of densely labeled cells being present in many steroid-sensitive areas including the medial preoptic nucleus, several hypothalamic nuclei, five song control nuclei (HVc, the lateral and medial portion of the magnocellular nucleus of the anterior neostriatum, area X and the nucleus uvaeformis) and several catecholaminergic areas (area ventralis of Tsai, substantia nigra, locus coeruleus). The volume of two song control nuclei, HVc and area X were reconstructed based on the boundaries of the cell groups exhibiting a denser SRC-1 expression as compared to the surrounding areas. Sex differences in the expression of SRC-1 were also detected in several song control nuclei. In particular, the volume of HVc based on the high density of SRC-1 expression was significantly larger in males than in females. The effect of steroids on the song control system could be, at least in part, indirect and result from a modulation by steroids of the catecholaminergic inputs to the song control nuclei. The presence of the steroid receptor coactivator SRC-1 in the telencephalic song control nuclei and in the catecholaminergic cell groups that innervate the song system supports the idea that SRC-1 expression could play an active role in the control of singing behavior by modulating estrogen and androgen receptor action at both locations. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailDe novo backbone and sequence design of an idealized alpha/beta-barrel protein: Evidence of stable tertiary structure
Offredi, Fabrice; Dubail, Fabien; Kischel, Philippe ULiege et al

in Journal of Molecular Biology (2003), 325(1), 163-174

We have designed, synthesized, and characterized a 216 amino acid residue sequence encoding a putative idealized alpha/beta-barrel protein. The design was elaborated in two steps. First, the idealized ... [more ▼]

We have designed, synthesized, and characterized a 216 amino acid residue sequence encoding a putative idealized alpha/beta-barrel protein. The design was elaborated in two steps. First, the idealized backbone was defined with geometric parameters representing our target fold: a central eight parallel-stranded beta-sheet surrounded by eight parallel alpha-helices, connected together with short structural turns on both sides of the barrel. An automated sequence selection algorithm, based on the dead-end elimination theorem, was used to find the optimal amino acid sequence fitting the target structure. A synthetic gene coding for the designed sequence was constructed and the recombinant artificial protein was expressed in bacteria, purified and characterized. Far-UV CD spectra with prominent bands at 222nm and 208nm revealed the presence of alpha-helix secondary structures (50%) in fairly good agreement with the model. A pronounced absorption band in the near-UV CD region, arising from immobilized aromatic side-chains, showed that the artificial protein is folded in solution. Chemical unfolding monitored by tryptophan fluorescence revealed a conformational stability (DeltaG(H2O)) of 35kJ/mol. Thermal unfolding monitored by near-UV CD revealed a cooperative transition with an apparent T(m) of 65 degrees C. Moreover, the artificial protein did not exhibit any affinity for the hydrophobic fluorescent probe 1-anilinonaphthalene-8-sulfonic acid (ANS), providing additional evidence that the artificial barrel is not in the molten globule state, contrary to previously designed artificial alpha/beta-barrels. Finally, 1H NMR spectra of the folded and unfolded proteins provided evidence for specific interactions in the folded protein. Taken together, the results indicate that the de novo designed alpha/beta-barrel protein adopts a stable three-dimensional structure in solution. These encouraging results show that de novo design of an idealized protein structure of more than 200 amino acid residues is now possible, from construction of a particular backbone conformation to determination of an amino acid sequence with an automated sequence selection algorithm. [less ▲]

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See detailDifferential expression of plasminogen activator inhibitor-1, tumor necrosis factor-alpha, TNF-alpha converting enzyme and ADAMTS family members in murine fat territories
Vörös, Gabor; Maquoi, Erik ULiege; Collen, Désiré et al

in Biochimica et Biophysica Acta-Gene Structure and Expression (2003), 1625(1), 36-42

ur objective was to investigate expression of A disintegrin and metalloproteinase (ADAM) and ADAM proteins with a thrombospondin (TS) motif (ADAMTS) family members in adipose tissue of lean and obese mice ... [more ▼]

ur objective was to investigate expression of A disintegrin and metalloproteinase (ADAM) and ADAM proteins with a thrombospondin (TS) motif (ADAMTS) family members in adipose tissue of lean and obese mice. Five-week-old male mice were kept on standard chow (SFD) or on high fat diet (HFD) for 15 weeks, and subcutaneous (SC) and gonadal (GON) adipose tissue, as well as mature adipocytes and stromal–vascular (S–V) cells were harvested. mRNA levels of plasminogen activator inhibitor-1 (PAI-1), tumor necrosis factor-α (TNF-α), ADAM-17 (TACE or TNF-α converting enzyme), ADAMTS-1 and ADAMTS-8 were quantified in isolated adipose tissues and cell fractions, and during differentiation of murine preadipocytes. The HFD resulted in a significantly enhanced weight of isolated SC and GON fat pads, and in enhanced blood levels of glucose, cholesterol and PAI-1. ADAM-17, TNF-α, PAI-1, ADAMTS-1 and ADAMTS-8 mRNA were detected in both SC and GON adipose tissue of lean mice (SFD). In SC adipose tissue of obese mice (HFD), the expression of ADAM-17 and PAI-1 was enhanced and that of ADAMTS-1 reduced, whereas in GON adipose tissue expression of TNF-α was enhanced and that of ADAMTS-8 reduced. In lean and obese mice, expression of ADAM-17, ADAMTS-1 and ADAMTS-8 was higher in the S–V cell fraction than in mature adipocytes. During differentiation of murine 3T3-F442A preadipocytes, expression of ADAM-17 and ADAMTS-1 remained virtually unaltered, whereas that of ADAMTS-8 decreased as adipocytes matured. Several ADAM and ADAMTS family members are expressed in adipose tissue and during differentiation of preadipocytes. Modulation of their expression upon development of obesity is adipose tissue-dependent. [less ▲]

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See detailLong-term optical spectrophotometric monitoring of comet C/1995 O1 (Hale-Bopp)
Rauer, H.; Helbert, J.; Arpigny, Claude ULiege et al

in Astronomy and Astrophysics (2003), 397

We observed comet C/1995 O1 (Hale-Bopp) at 4.6-2.9 AU pre-perihelion and 2.8-12.8 AU post-perihelion with optical long-slit spectroscopy. Emission bands of CN, C[SUB]3[/SUB], C[SUB]2[/SUB] and NH[SUB]2 ... [more ▼]

We observed comet C/1995 O1 (Hale-Bopp) at 4.6-2.9 AU pre-perihelion and 2.8-12.8 AU post-perihelion with optical long-slit spectroscopy. Emission bands of CN, C[SUB]3[/SUB], C[SUB]2[/SUB] and NH[SUB]2[/SUB] have been covered. Emission of C[SUB]3[/SUB] was detected up to 7.0 AU, and CN could be followed up to 9.8 AU post-perihelion. Spatial column density profiles of the radicals have been used to derive effective parent Haser scale lengths for heliocentric distances beyond 3 AU. Production rates were derived based on these Haser scale lengths. The observations of CN are in agreement with HCN as the major parent molecule of this radical at large distances from the Sun (i.e. beyond ~ 3 AU). We compare the measured CN production rate to sublimation rates of HCN from a simple nucleus sublimation model. The variation of CN production rates with changing heliocentric distance gives no indication for sublimation from the interior and is consistent with very little thermal lag of the nucleus. Based on observations collected at the European Southern Observatory, Chile, and the Observatoire de Haute Provence, France. [less ▲]

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See detailNutritionally induced obesity is attenuated in transgenic mice overexpressing plasminogen activator inhibitor-1
Lijnen, Roger; Maquoi, Erik ULiege; Morange, Pierre et al

in Arteriosclerosis, Thrombosis, and Vascular Biology (2003), 23(1), 78-84

OBJECTIVE: The objective of this study was to investigate the role of plasminogen activator inhibitor-1 (PAI-1) in adipose tissue development in vivo. METHODS AND RESULTS: Transgenic (Tg) mice ... [more ▼]

OBJECTIVE: The objective of this study was to investigate the role of plasminogen activator inhibitor-1 (PAI-1) in adipose tissue development in vivo. METHODS AND RESULTS: Transgenic (Tg) mice overexpressing murine PAI-1 under control of the adipocyte promoter aP2 and wild-type (WT) controls were kept on standard food (SFD) or on high-fat diet (HFD) for 15 weeks. The body weight and the weight of the isolated subcutaneous and gonadal fat deposits of the Tg mice kept on the HFD were significantly lower than those of the WT mice. The number of adipocytes in the adipose tissue was similar for Tg and WT mice on the HFD, but adipocyte hypotrophy and a significantly lower ratio of stroma cells/adipocytes were observed in the Tg mice. A significant negative correlation (P<0.01) was observed between expression of preadipocyte factor-1, which blocks adipocyte differentiation, and adipose tissue weight. Fasting insulin and total cholesterol levels on the HFD were lower in Tg than in WT mice. CONCLUSIONS: High circulating PAI-1 levels attenuate nutritionally induced obesity. This may be related to modifications in adipose tissue cellularity affecting weight and plasma metabolic parameters. [less ▲]

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See detailClose pairs of quasars with different redshifts: New observations and results
Sluse, Dominique ULiege; Surdej, Jean ULiege; Claeskens, Jean-François ULiege et al

in Astronomy and Astrophysics (2003), 397

Burbidge et al. (\cite {burbidge}) argue that the observed number of quasar pairs with small angular separations and different redshifts (typically Delta theta <= 5 arcsec and Delta z > 0.1 ) is not ... [more ▼]

Burbidge et al. (\cite {burbidge}) argue that the observed number of quasar pairs with small angular separations and different redshifts (typically Delta theta <= 5 arcsec and Delta z > 0.1 ) is not compatible with a random distribution of quasars over the sky. After a brief review of all known quasar pairs with different redshifts, we show by means of very simple calculations that the probability of finding the three accepted pairs accidentally is of the order of 10%. We conclude that, under realistic hypotheses, the observed number of quasar pairs with different redshifts is not unlikely. We also present arguments showing that gravitational lensing biases are probably not strong enough to significantly increase the expected number of quasar pairs. The failure to detect with HST a secondary lensed image of the background quasar near the foreground one in these three pairs supports this view. [less ▲]

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See detailFire tests and calculation methods for circular concrete columns
Franssen, Jean-Marc ULiege; Dotreppe, Jean-Claude ULiege

in Fire Technology (2003), 39(1), 89-97

The introduction sets the scene of the present paper i.e. the extensive research works performed at the University of Liege in order to derive acceptable calculation methods for the re design of concrete ... [more ▼]

The introduction sets the scene of the present paper i.e. the extensive research works performed at the University of Liege in order to derive acceptable calculation methods for the re design of concrete columns. It is explained that all previous works have been based on square or rectangular cross sections, for which corner spalling was observed very often, whereas circular section are nowadays becoming more and more popular. In order to examine the influence of the circular shape on the behavior under re conditions, an experimental research study has been performed recently at the University of Liege. This paper describes the test procedure, the observations made, and the values obtained for the re resistance. Theoretical methods have been developed for a quick, safe, and efficient design of concrete columns under re conditions. These methods have been applied successfully to the recently tested circular columns. [less ▲]

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See detailEffects of Alzheimer's disease on the recognition of novel versus familiar words : Neuropsychological and clinico-metabolic data
Lekeu, Françoise ULiege; Van der Linden, Martial ULiege; Degueldre, Christian ULiege et al

in Neuropsychology (2003), 17(1), 143-154

This study explored recognition memory performance for novel versus familiar words in Alzheimer's disease (AD) patients and normal controls (NCs), using an adaptation of E. Tulving and N. Kroll's (1995 ... [more ▼]

This study explored recognition memory performance for novel versus familiar words in Alzheimer's disease (AD) patients and normal controls (NCs), using an adaptation of E. Tulving and N. Kroll's (1995) procedure. Results showed that both groups exhibited more hits and more false alarms for familiar than for novel words. The groups did not differ in the recognition of familiar words, reflecting preserved familiarity processes in AD. However, AD patients made more false alarms than NCs in the recognition of novel words, reflecting impairment of recollection processes in AD. A positron emission tomography analysis of clinico-metabolic correlations in AD patients showed a correlation between recognition of novel words and right hippocampal activity, whereas recognition of familiar words was more related to metabolic activity in the left posterior orbitofrontal cortex. [less ▲]

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