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See detailAller voir ailleurs si j'y suis. Hergé, Michaux, Simenon
Denis, Benoît ULg

in Textyles : Revue des Lettres Belges de Langue Française (1995), (12), 121-136

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See detailEvidence for a Second Receptor Binding Site on Human Prolactin
Goffin, Vincent; Struman, Ingrid ULg; Mainfroid, V. et al

in Journal of Biological Chemistry (1994), 269(51), 32598-606

The existence of a second receptor binding site on human prolactin (hPRL) was investigated by site-directed mutagenesis. First, 12 residues of helices 1 and 3 were mutated to alanine. Since none of the ... [more ▼]

The existence of a second receptor binding site on human prolactin (hPRL) was investigated by site-directed mutagenesis. First, 12 residues of helices 1 and 3 were mutated to alanine. Since none of the resulting mutants exhibit reduced bioactivity in the Nb2 cell proliferation bioassay, the mutated residues do not appear to be functionally necessary. Next, small residues surrounding the helix 1-helix 3 interface were replaced with Arg and/or Trp, the aim being to sterically hinder the second binding site. Several of these mutants exhibit only weak agonistic properties, supporting our hypothesis that the channel between helices 1 and 3 is involved in a second receptor binding site. We then analyzed the antagonistic and self-antagonistic properties of native hPRL and of several hPRLs analogs altered at binding site 1 or 2. Even at high concentrations (approximately 10 microM), no self-inhibition was observed with native hPRL; site 2 hPRL mutants self-antagonized while site 1 mutants did not. From these data, we propose a model of hPRL-PRL receptor interaction which slightly differs from that proposed earlier for the homologous human growth hormone (hGH) (Fuh, G., Cunningham, B. C., Fukunaga, R., Nagata, S., and Goeddel, D. V., and Well, J. A. (1992) Science 256, 1677-1680). Like hGH, hPRL would bind sequentially to two receptor molecules, first through site 1, then through site 2, but we would expect the two sites of hPRL to display, unlike the two binding sites of hGH, about the same binding affinity, thus preventing self-antagonism at high concentrations. [less ▲]

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See detailA conserved 5' to 3' exonuclease activity in yeast and human nucleotide excision repair protein RAD2 and XPG
Habraken, Yvette ULg; Sung, Patrick; Prakash, Louise et al

in Journal of Biological Chemistry (1994), 269(50), 31342-5

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See detailTraitement de l'ostéoporose: données actuelles et perspectives
Reginster, Jean-Yves ULg; Deroisy, Rita ULg; Franchimont, P.

in Revue du Rhumatisme (1994), 61(10, Pt 2), 155-164

Postmenopausal osteoporosis is characterized not only by a reduction in bone mass but also by bone microarchitecture alterations, which result in greater bone frailty and in an increased fracture risk ... [more ▼]

Postmenopausal osteoporosis is characterized not only by a reduction in bone mass but also by bone microarchitecture alterations, which result in greater bone frailty and in an increased fracture risk. Many drugs have been studied to determine whether they prevent bone loss or reduce the incidence of additional fractures in patients with established osteoporosis. Primary prevention of osteoporosis rests on regular exercising and adequate intake of dietary calcium. For secondary prevention in women undergoing menopause, replacement estrogen therapy given for at least ten years is associated with substantial reductions in fractures of the radius, hip, and spine. Other drugs capable of arresting postmenopausal bone loss include parenteral, nasal or rectal calcitonin and diphosphonates. However, the long-term safety of the latter requires further evaluation. Current studies are evaluating new molecules with potential preventive efficacy, such as ipriflavone. There is no general consensus about the efficacy of treatments for established osteoporosis with fractures. To date, no controlled studies have demonstrated a reduction in the incidence of further fractures in patients given calcium alone. Studies of hydroxylated vitamin D derivatives have been disappointing, although daily administration of vitamin D3 in combination with calcium significantly reduced the incidence of nonvertebral fractures in a population of elderly institutionalized subjects. Plausible explanations for this effect include increased vitamin D levels and reduced parathyroid levels in the bloodstream. Parenteral or nasal calcitonin stabilizes or increases bone mineral content in both cancellous and cortical bone. This effect is especially marked in high-turn-over patients. Several lines of evidence suggest that calcitonin therapy has a protective effect against vertebral and hip fractures. In patients with osteoporosis, oral or intravenous diphosphonates are associated with a significant increase in cancellous bone mass with no loss of cortical bone. Etidronate may be especially beneficial in severe osteoporosis with marked loss of bone and multiple vertebral crush fractures. Fluoride stimulates the growth and synthetic activity of osteoblasts. Accurate information is needed on the optimal dosage of fluoride, on the effects of fluoride on the appendicular skeleton, and, above all, on the biomechanical properties of the bone produced under fluoride therapy. In addition to these commercially available drugs, several other agents are at various stages of the development process.(ABSTRACT TRUNCATED AT 400 WORDS) [less ▲]

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See detailMaladie de Kaposi chez une patiente souffrant d'une immunodéficience acquise VIH négative
Nikkels, Arjen ULg; Collignon, Jacques ULg; Moutschen, M. P. et al

in Presse Médicale (1994), 23(38), 1760-1761

A 79-year-old woman of Mediterranean ascent suffered from corticosteroid-dependent chronic obstructive lung disease, hypogammaglobulinemia (IgG 1 and 2), decreased CD16 natural killer cell function and ... [more ▼]

A 79-year-old woman of Mediterranean ascent suffered from corticosteroid-dependent chronic obstructive lung disease, hypogammaglobulinemia (IgG 1 and 2), decreased CD16 natural killer cell function and non-HIV related CD4 and CD8 lymphopenia. Such immunodeficiency could be either a variant of common variable immunodeficiency or an early stage of the idiopathic CD4 + T lymphocytopenia syndrome. She developed bilateral lesions of Kaposi's sarcoma on the lower extremities resembling the classic European type of the disease. The tumors contained both CD34 + and Factor XIIIa + cells. The HLA-DR5 haplotype was not found. Weekly low intravenous dosages of vinblastine improved the lesions but the patient died from pontic infarction. [less ▲]

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See detailA flare event on HR2517
Sterken, C.; Manfroid, Jean ULg

in Information Bulletin on Variable Stars (1994), 4120

Not Available

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See detailA kinetic model of the formation of the hot oxygen geocorona. 1: Quiet geomagnetic conditions
Shematovich, V. I.; Bisikalo, D. V.; Gérard, Jean-Claude ULg

in Journal of Geophysical Research (1994), 99

A model of the hot oxygen geocorona in the transition region near the exobase is described. It is based on a Monte Carlo solution of the nonlinear Boltzmann equation for hot oxygen atoms produced by ... [more ▼]

A model of the hot oxygen geocorona in the transition region near the exobase is described. It is based on a Monte Carlo solution of the nonlinear Boltzmann equation for hot oxygen atoms produced by chemical processes usually considered as a source of hot oxygen (photodissociation of O2 and dissociative recombination of O2(+) and NO(+) ions). The evolution of the system is described stochastically as a series of random Markovian processes. The energy distribution function of the thermal and non-thermal O(3P) atoms and of the nonthermal O(1D) atoms is calculated from the thermospheric collision-dominated region to the exosphere where the gas flow is virtually collisionless. The model is applied to equatorial latitudes for conditions of low solar and geomagnetic activity. Numerical simulations show that the distribution function of thermal oxygen is increasingly perturbed by collisions with the hot oxygen population at high altitudes and departs significantly from a Maxwellian distribution at all altitudues. The number density and temperature of the nonthermal oxygen atoms are derived from their microscopic distribution function and found tobe in qualitative agreement with previous theoretical and experimental estimates. [less ▲]

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See detailLes phéromones humaines: vestige animal ou réalité non reconnue
Foidart, Agnès ULg; Legros, Jean-Jacques ULg; Balthazart, Jacques ULg

in Revue Médicale de Liège (1994), 49(12), 662-80

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See detailEpithelial-to-Mesenchymal Transition in Hpv-33-Transfected Cervical Keratinocytes Is Associated with Increased Invasiveness and Expression of Gelatinase A
Gilles, Christine ULg; Polette, M.; Piette, Jacques ULg et al

in International Journal of Cancer = Journal International du Cancer (1994), 59(5), 661-6

The invasive potential of a set of HPV-33- and HPV-33 + ras-transfected cervical keratinocytes was investigated. These cell lines were previously separated into 2 groups according to their behavior on ... [more ▼]

The invasive potential of a set of HPV-33- and HPV-33 + ras-transfected cervical keratinocytes was investigated. These cell lines were previously separated into 2 groups according to their behavior on collagen rafts. Cell lines from the first group reconstituted CINIII-like lesions, whereas cell lines from the second group reconstituted epithelia comparable to micro-invasive carcinomas. They were thus postulated to represent distinct stages of cervical carcinogenesis. The present results have shown that lines from group I, which have conserved an epithelial morphology in monolayer, (i) could not invade matrigel when tested in a modified Boyden chamber assay, (ii) produced solely gelatinase B and (iii) were unable to activate exogenous gelatinase A. On the other hand, lines from group II associated epithelial-to-mesenchymal transition (acquisition of elongated morphology, vimentin positivity) with high in vitro invasive potential and with the ability both to produce and to activate gelatinase A. These results strongly support the hypothesis that the epithelial-to-mesenchymal transition and the associated events might be implicated in the progression to the metastatic phenotype. [less ▲]

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See detail(Erratum) Further observational evidence that MG J0414+0534 is a gravitational mirage.
Angonin-Willaime, M.-C.; Vanderriest, C.; Hammer, F. et al

in Astronomy and Astrophysics (1994), 292

In Sect. 3.3, the identifications of components A1 and A2 for the optical data were inadvertently inverted. This does not change substantially the discussion; just read A1 for A2 and vice versa. In ... [more ▼]

In Sect. 3.3, the identifications of components A1 and A2 for the optical data were inadvertently inverted. This does not change substantially the discussion; just read A1 for A2 and vice versa. In particular, the ratio A2/A1 = 0.3 cannot be made compatible with the radio value without one or several of the mechanisms we suggested. We apologize for the error and thank Dr S. Mao for bringing it to our attention. Erratum to Astron. Astrophys. 281, 388-394 (1994) [less ▲]

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See detailThe physiological status of the ovarian donor affects the in-vitro development of isolated bovine preantral follicles
FIGUEIREDO, J. R.; HULSHOF, S. C. J.; VANDENHURK, R. et al

in Theriogenology (1994), 42(8), 1303-1310

Described in the present paper is the effect of the physiological status of the ovarian donor on the development of isolated bovine preantral follicles during 5 d of culture. The preantral follicles were ... [more ▼]

Described in the present paper is the effect of the physiological status of the ovarian donor on the development of isolated bovine preantral follicles during 5 d of culture. The preantral follicles were isolated mechanically from ovaries of calves, or nonpregnant, pregnant and postpartum cows collected at the slaughterhouse. There were no differences observed among calves, nonpregnant and pregnant cows, neither in the percentages of morphologically normal follicles, nor in the mean diameter increase during culture. However, preantral follicles isolated from postpartum animals had a lower viability during culture, as demonstrated by significantly lower percentages of morphologically normal and growing follicles as well as by a levier mean diameter increase. Our findings show that the ovarian source may affect development of bovine preantral follicles in vitro, especially when preantral follicles from postpartum cows were used. [less ▲]

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See detailDyBa2Cu307-Y superconducting materials synthesized in-situ in a magnetic-field - relations between structure and properties
Cloots, Rudi ULg; Diko, P.; Godelaine, P. A. et al

in Physica C: Superconductivity (1994), 235(Part 1), 357-358

We have synthesized c-axis oriented magnetically melt textured grown DyBa2Cu3O7-y samples at 1035 degrees C under 0.6 T magnetic induction. We discuss the crystal growth mechanism of such 123 melt ... [more ▼]

We have synthesized c-axis oriented magnetically melt textured grown DyBa2Cu3O7-y samples at 1035 degrees C under 0.6 T magnetic induction. We discuss the crystal growth mechanism of such 123 melt textured grown superconducting ceramics. A strictly tridimensional model is proposed based on Schmitz et al. model, taking into account the peculiar physical properties reported for such materials. In particular a filamentary one dimensional electron conduction path at the percolation threshold is emphasized. We have used optically polarized ligth microscopy as well as electron microscopy analysis to deduce the growth steps. [less ▲]

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See detailDépression: Intérêt de la variation contingente négative
Papart, Patrick ULg

in Dialogue/Depression (1994)

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See detailSimulated growth front of 123-(RE)BCO near 211 particles
Vandewalle, Nicolas ULg; Cloots, Rudi ULg; Ausloos, Marcel ULg

in Physica C: Superconductivity (1994), 235(Part 1), 427-428

The microstructural features observed on some DyBa2Cu3O7-x, samples show that kinetic considerations are as important as thermodynamic ones. In order to compute and characterize the kinetic growth front ... [more ▼]

The microstructural features observed on some DyBa2Cu3O7-x, samples show that kinetic considerations are as important as thermodynamic ones. In order to compute and characterize the kinetic growth front of 123-(RE)BCO compounds, we have introduced an anisotropic growth direction into a simple two-dimensional growth model: the Eden model defined on a square lattice. The presence of 211 particles has been also considered. The simulated patterns in the ab and ac planes agree with observations and contribute to a more comprehensive model of the kinetic of the growth front near 211 particles. [less ▲]

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See detailVaricelle et zona: Virus VZV, étiologie, complications et traitement
Rentier, Bernard ULg; Piette, Jacques ULg; Nikkels, Arjen ULg

in Patient Care (1994), 17

La varicelle est une affection très fréquente et très contagieuse. Presque toujours bénigne chez l'enfant, elle peut être plus grave chez l'adulte. Quant au zona, il frappe essentiellement les adultes. C ... [more ▼]

La varicelle est une affection très fréquente et très contagieuse. Presque toujours bénigne chez l'enfant, elle peut être plus grave chez l'adulte. Quant au zona, il frappe essentiellement les adultes. C'est le seul et même virus de la varicelle et du zona (Varicella-Zoster Virus, VZV) qui constitue le lien commun entre les 2 maladies. Sa particularité est de fonctionner par disparition-réactivation. Le VZV appartient à la famille des Herpesviridae. Proche des autres Herpès-virus comme les virus de l'Herpes simplex (HSV-1 et HSV-2), le cytomégalovirus (CMV), le virus d'Epstein-Barr (EBV) et les Herpèsvirus humains 6 et 7 (HHV-6 et HHV-7) nouvellement décrits, il possède néanmoins certaines caractéristiques propres. [less ▲]

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See detailA novel glycoprotein of the aspartic proteinase gene family expressed in bovine placental trophectoderm
Xie, Sancai; Low, Boon G.; Nagel, Robert J. et al

in Biology of Reproduction (1994), 51(6), 1145-1153

The pregnancy associated glycoproteins (PAG 1) that appear in the maternal serum of cattle and sheep soon after implantation are apparently inactive members of the aspartic proteinase family. Here we ... [more ▼]

The pregnancy associated glycoproteins (PAG 1) that appear in the maternal serum of cattle and sheep soon after implantation are apparently inactive members of the aspartic proteinase family. Here we describe the isolation of a highly abundant cDNA (PAG 2 cDNA) that represents a second member of this gene family which is structurally related to bovine PAG 1, ovine PAG 1, and pepsin (58%, 58%, and 51% amino acid sequence identity, respectively). The bovine PAG 2 cDNA was identified in two ways. First, the bovine placental library was screened under relatively nonstringent conditions with an ovine PAG 1 cDNA. The second fortuitous approach employed immunoscreening with an antiserum raised against a partially purified factor that competed with bovine LH for binding to the LH receptor on the CL of the ovary. The full-length cDNA (1258 bp) codes for a polypeptide of 376 amino acids. Bovine PAG 2, unlike bovine PAG 1, has a catalytic center with a consensus sequence of amino acids. Its mRNA is expressed in fetal placenta but not in other fetal organs, and is localized to both the mononucleate and binucleate cells of the trophectoderm, whereas PAG 1 is expressed only in binucleate cells. PAG 2 is synthesized by placental explants as a 70-kDa glycoprotein that is processed to several smaller molecules. Western blot analysis of culture media developed with epitope-selected antibodies to PAG 2 reveals several bands ranging in apparent M(r) from 31,000-70,000, which correspond in size to the polypeptides present in the preparation used for immunization [less ▲]

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See detailReduction of Temporalis Exteroceptive Suppression by Peripheral Electrical Stimulation in Migraine and Tension-Type Headaches
Wang, W.; Schoenen, Jean ULg

in Pain (1994), 59(3), 327-34

Inhibition of the second exteroceptive suppression of temporalis muscle activity (ES2) produced by a preceding electrical stimulus applied at the index was studied in patients suffering from migraine ... [more ▼]

Inhibition of the second exteroceptive suppression of temporalis muscle activity (ES2) produced by a preceding electrical stimulus applied at the index was studied in patients suffering from migraine without aura (MO), chronic (CTH) or episodic (ETH) tension-type headache. Each patient group comprised of 12 subjects was compared to a group of healthy controls. Mean duration of unconditioned ES2, measured on 10 averaged rectified responses after labial stimulation at a 0.1 Hz frequency, was reduced in CTH only. From stimulation intensities of 20 mA onward, peripheral-induced inhibition of temporalis ES2 was significantly more pronounced in both subtypes of tension-type headache compared to migraineurs or controls. After an index finger stimulus of 20 mA, temporalis ES2 was abolished in 83% of CTH, 67% of ETH, 25% of MO patients and 8% of controls, whereas unconditioned ES2 was present in all patients. Among 9 ETH patients with normal (> or = 32 msec) unconditioned ES2, 5 had total disappearance of ES2 after a 20 mA index stimulation. These results demonstrate that peripheral conditioning at 20 mA increases the diagnostic sensitivity of ES2 studies. They suggest that the changes observed in tension-type headache are due to hyperexcitability of the reticular nuclei which inhibit the medullary inhibitory interneurons mediating ES2. [less ▲]

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See detailEvaluation de la durée de vie des outils de fraisage
Debongnie, Jean-François ULg

in European Journal of Mechanical and Environmental Engineering (1994), 39(3), 151-155

A method of prediction of the life of milling tools is presented. Founded on the cumulative damage principle, this method evenly covers peripherical and face milling. In the latter case, the theory is ... [more ▼]

A method of prediction of the life of milling tools is presented. Founded on the cumulative damage principle, this method evenly covers peripherical and face milling. In the latter case, the theory is illustrated by a comparison of symmetrical and asymmetrical face milling from the point of view of tool life. [less ▲]

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See detailDe ruimtebeleving in Vestdijks Verzamelde verhalen I
Nachtergaele, Lutgarde ULg

in Vestdijkkroniek (1994), 85

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See detailExpression of gelatinases A and B and their tissue inhibitors by cells of early and term human placenta and gestational endometrium
Polette, Myriam; Nawrocki, B.; PINTIAUX, Axelle ULg et al

in Laboratory Investigation : Journal of Technical Methods & Pathology (1994), 71(6), 838-846

BACKGROUND: Human placentation is mediated by fetal trophoblastic cells that invade the maternal uterine endometrium. Trophoblast invasion requires a precisely regulated secretion of specific proteolytic ... [more ▼]

BACKGROUND: Human placentation is mediated by fetal trophoblastic cells that invade the maternal uterine endometrium. Trophoblast invasion requires a precisely regulated secretion of specific proteolytic enzymes able to degrade the endometrial basement membrane and extracellular matrix. EXPERIMENTAL DESIGN: Several studies have documented the key roles of matrix metalloproteinases and their tissue inhibitors in the invasion of various matrices by cultured trophoblasts. In vitro studies suggest that placentation could result from a balance between the secretion of these enzymes by trophoblast cells and their inhibition by the natural tissue inhibitors (TIMPs) produced by maternal decidual cells. The precise localization and levels of expression of these proteins that account for and control invasion during human placentation in vivo however, have not been described. We have evaluated, in vivo, by immunohistochemistry, Northern blot analysis and in situ hybridization, the expression of two metalloproteinases (gelatinases A and B) and their two tissue inhibitors (TIMPs 1 and 2) in placental villi and placental beds of first and third trimesters of normal pregnancy. RESULTS: Human first trimester intermediate trophoblast produced both gelatinases A and B; these two gelatinases were respectively less and no more detected at term in these cells. We found that both TIMP1 and 2 were also expressed in maternal decidual cells with a dramatic increase of TIMP1 at the term of pregnancy. In floating villi, gelatinase A and TIMP1 were localized in the stromal compartment, whereas gelatinase B and TIMP2 were codistributed in trophoblast cells. CONCLUSIONS: The gelatinases A and B and their tissue inhibitors are thus expressed by specific cells in early and late placental beds and villi. This pattern of expression varies during pregnancy. Therefore, our morphologic study supports biologic findings suggesting that these proteins may participate in placentation. [less ▲]

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See detailViral glycoproteins in herpesviridae granulomas
Nikkels, Arjen ULg; Debrus, S.; Delvenne, Philippe ULg et al

in American Journal of Dermatopathology (1994), 16(6), 588-592

Granulomatous reactions after varicella zoster virus (VZV) and herpes simplex virus (HSV) infections are rare, and their pathogenesis remains unclear. We studied by immunohistochemistry and in situ ... [more ▼]

Granulomatous reactions after varicella zoster virus (VZV) and herpes simplex virus (HSV) infections are rare, and their pathogenesis remains unclear. We studied by immunohistochemistry and in situ hybridization early granulomatous reactions after VZV and HSV infections. In the five cases studied, the VZV glycoproteins gp I and gp II were present in cells abutted to altered vessels, but the corresponding genome sequences were disclosed in similar locations in only one of these cases. In an immunocompromised patient with diffuse HSV eruption, HSV I antigens were present in cells of the reticular dermis, while viral nucleic acids were not evident. Immunophenotyping of the granulomas showed strong Mac 387 and CD68 positive labelings of macrophages/monocytes, without any involvement of Factor XIIIa-positive cells. These findings suggest that the major viral envelope glycoproteins, rather than complete viral particles could trigger granuloma formation following HSV and VZV skin infections. [less ▲]

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See detailTyping of Clostridium Perfringens by in Vitro Amplification of Toxin Genes
Daube, Georges ULg; China, Bernard; Mainil, Jacques ULg et al

in Journal of Applied Bacteriology (1994), 77(6), 650-655

The strains of Clostridium perfringens are classified according to major toxins produced. Classically, this determination involves the seroneutralization of their lethal effect in mice. However, this ... [more ▼]

The strains of Clostridium perfringens are classified according to major toxins produced. Classically, this determination involves the seroneutralization of their lethal effect in mice. However, this method requires specific antisera and a large number of mice. In this work, a new typing method was developed based on the amplification of toxin genes by polymerase chain reaction (PCR). By combination of several pairs of primers, the toxinotype of a Cl. perfringens strain was determined by looking at the pattern of bands on an agarose gel electrophoresis. This mixture contained primers amplifying simultaneously a part of alpha-toxin, beta-toxin, epsilon-toxin and enterotoxin genes. In order to distinguish between toxinotype A and E, the l-toxin gene fragment must be amplified in a separate PCR reaction. Moreover, with the primers combination, in most cases, a PCR product corresponding to the alpha-toxin gene was obtained from direct enrichments of animal intestinal contents. [less ▲]

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See detailCryptocrine Signaling in the Thymus Network. Implications for Central T-Cell Tolerance of Neuroendocrine Functions
Geenen, Vincent ULg; Cormann-Goffin, Nadine; Vandersmissen, Eric et al

in Annals of the New York Academy of Sciences (1994), 741

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See detailHeavy fermion behavior of U2T2X compounds
Havela, Ladislav; Sechovsky, Vladimir; Svoboda, P. et al

in Journal of Applied Physics (1994), 76(10), 6214-6215

Magnetic and specific-heat studies of U2T2X compounds show a frequent occurrence of the gamma enhancement in conjunction with the onset of antiferromagnetic ordering. The largest value of 830 mJ/mol K**2 ... [more ▼]

Magnetic and specific-heat studies of U2T2X compounds show a frequent occurrence of the gamma enhancement in conjunction with the onset of antiferromagnetic ordering. The largest value of 830 mJ/mol K**2 was observed in U2Pt2In, which is nonmagnetic down to 1.2 K. Variations of electronic structure are documented by optimized relativistic LCAO calculation. [less ▲]

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See detailLe traitement bronchodilatateur du patient BPCO (1994)
Bury, Thierry ULg; Corhay, Jean-Louis ULg; Louis, Renaud ULg et al

in Revue Médicale de Liège (1994), 49(11), 593-5

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See detailAstroglia-Released Factor Shows Similar Effects as Benzodiazepine Inverse Agonists
Rigo, Jean-Michel; Belachew, Shibeshih ULg; Lefebvre, P. P. et al

in Journal of Neuroscience Research (1994), 39(4), 364-76

Media conditioned by cultured neonatal cerebral cortex microexplants (CCM) or astrocytes (ACM) contain low molecular weight (< 1,000 Da) substance(s) which inhibits the gamma aminobutyric acid (GABA ... [more ▼]

Media conditioned by cultured neonatal cerebral cortex microexplants (CCM) or astrocytes (ACM) contain low molecular weight (< 1,000 Da) substance(s) which inhibits the gamma aminobutyric acid (GABA)-induced inward current recorded in cerebellar granule cells and hippocampal neurons in culture using the whole-cell patch-clamp technique. This effect is specific for CCM and ACM, as medium conditioned by PC12 cells (PC12CM) does not affect the GABA response of these cells. It is also specific for GABA-induced currents because glutamate-induced currents do not change either in amplitude or in shape in the presence of CCM or ACM. The inhibitory effect on the GABA response in cerebellar granule cells of both ACM and CCM could be suppressed by flumazenil, a specific benzodiazepine (BZD) antagonist and could be mimicked by two BZD inverse agonists. These data thus demonstrate the presence of a BZD inverse agonist-like activity in CCM and ACM. This effect of ACM on different neuronal cell types was heterogenous since no detectable effect could be observed on the GABA-induced current in GABA-responsive dorsal root ganglion (DRG) neurons, presumably reflecting a functional heterogeneity of the GABAA receptors present in these different neuronal subsets. By the release of such an endogenous BZD inverse agonist-like activity, glia cells could possibly modulate GABAA receptor-mediated responses. [less ▲]

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See detailThe morphology of the north Jovian ultraviolet aurora observed with the Hubble Space Telescope
Gérard, Jean-Claude ULg; Dols, Vincent; Prange, Renee et al

in Planetary and Space Science (1994), 42

A series of six images covering a complete rotation of the north polar region of Jupiter were obtained in February 1993 with the Faint Object Camera on board the Hubble Space Telescope (HST). These images ... [more ▼]

A series of six images covering a complete rotation of the north polar region of Jupiter were obtained in February 1993 with the Faint Object Camera on board the Hubble Space Telescope (HST). These images provide the first global picture of the morphology of the Jovian ultraviolet aurora observed from Earth orbit. The camera passband was centered near 153 nm, a region dominated by the H2 Lyman bands and continuum. The successive exposures, taken approximately 90 min apart, are used to construct a polar view of the auroral zone. It is found that the auroral emissions do not exactly follow the footprint of a constant L-shell although the size of the oval and its location agree best with the footprints of the approximately equal to 30 R[SUB]J[/SUB] field line in the GSFC O6 model of the Jovian magnetic field. The displacement between the observed auroral zone and the theoretical oval may indicate a possible distortion of the Jovian magnetic field lines near the surface. A comparison with two images at the same wavelength obtained 8 months earlier shows that the main morphological features are persistent, in spite of changes in the detailed emission distribution. Small scale features with characteristic sizes of approximately 1000 km are observed along the auroral oval. The change of morphology observed as a function of the System 3 longitude appears as a persistent characteristic of the morphology of the north polar aurora. [less ▲]

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See detailAre Similar Inflammatory Factors Involved in Strenuous Exercise and Sepsis?
Camus, G.; Deby, Ginette ULg; Duchateau, J. et al

in Intensive Care Medicine (1994), 20(8), 602-10

An increasing body of data suggest that strenuous exercise triggers an inflammatory response having some similarity with those occurring in sepsis. Indices of this inflammatory response to exercise (IRE ... [more ▼]

An increasing body of data suggest that strenuous exercise triggers an inflammatory response having some similarity with those occurring in sepsis. Indices of this inflammatory response to exercise (IRE) especially include leukocytosis, release of inflammatory mediators and acute phase reactants, tissue damage, priming of various white blood cell lines, production of free radicals; activation of complement, coagulation and fibrinolytic cascades. Inflammatory responses to strenuous exercise and sepsis could in part be due to the release of endotoxin in blood as common triggering factor, but it seems that tissue damage and/or contact system activation are more important triggering mechanisms in exercising subjects. While the magnitude and duration of cellular and humoral changes associated with IRE are quite different from those observed in sepsis, recent human studies suggested that chronic and/or excessive IRE could have adverse effects. Among the possible consequences of acute and chronic IRE are delayed onset muscular soreness and loss of force, cardiovascular complications, intravascular hemolysis, hypoferraemia and increased susceptibility to infection. [less ▲]

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See detailL'épilepsie essentielle au Rorschach et au Szondi
Stassart, Martine ULg

in Cahiers du CEP (Centre d'Etudes Pathoanalytiques) (1994), 4

Twenty essential epileptics were examined with help of the Rorschach and Szonditests.The results show that the classical signs of "épileptoïdie" are present by all the subjects. There is thus a specifical ... [more ▼]

Twenty essential epileptics were examined with help of the Rorschach and Szonditests.The results show that the classical signs of "épileptoïdie" are present by all the subjects. There is thus a specifical pattern of personnality by this seizure of epilepsy. [less ▲]

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See detailPretreatment minimal staging for non-small cell lung cancer: an updated consensus report
Barthelemy, Nicole ULg; Goldstraw; Rocmans et al

in Lung Cancer (1994), 11(3),

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See detailL'épilepsie de Vincent VAN GOGH
Blumer, Dietrich; Stassart, Martine ULg

in Cahiers du CEP (Centre d'Etudes Pathoanalytiques) (1994), 4(4), 3-10

Though he never had typical "grand mal" crisis, Vincent VAN GOGH was really epileptic. The symptomatology of epileptic seizures was better known in the XIXd Century than today.

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See detailVariable regions of chromosome 11 loss in different pathological tissues of a patient with the multiple endocrine neoplasia type I syndrome.
Beckers, Albert ULg; Abs, R.; Reyniers, E. et al

in Journal of Clinical Endocrinology and Metabolism (1994), 79(5), 1498-1502

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder characterized by nodular proliferation of the parathyroid glands and tumors of the anterior pituitary gland, the ... [more ▼]

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited disorder characterized by nodular proliferation of the parathyroid glands and tumors of the anterior pituitary gland, the endocrine pancreas, and the neuroendocrine cell system of the gut. Loss of the putative tumor suppressor effect of the MEN1 gene is probably responsible for the development of MEN1-associated tumors. We report here a genetic study of a female MEN1 patient with the association of nodular hyperplasia of two parathyroid glands, an insulinoma, multiple duodenal gastrinomas, a prolactinoma, and a gastric carcinoid. We performed loss of heterozygosity (LOH) studies of chromosome 11 on all affected tissues except the insulinoma. Allelic losses of chromosome 11 were detected in several tumors, but the chromosomal regions of LOH were different, suggesting that different somatic mutational events are involved in the pathogenesis of these tumors. LOH of chromosome 11 was also detected in the prolactinoma of this patient, which indicates that the MEN1 gene has a tumor suppressor effect in the pituitary. [less ▲]

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See detailPlasmatic profiles of pregnancy-associated glycoprotein and progesterone levels during gestation in Churra and Merino sheep
Ranilla, Marie-José; Sulon, Joseph ULg; Carro, M. D. et al

in Theriogenology (1994), 42(3), 537-545

This study was carried out to determine ovine pregnancy-associated glycoprotein (oPAG) and progesterone (P4) levels in the serum of Churra and Merino ewes throughout gestation and the first month post ... [more ▼]

This study was carried out to determine ovine pregnancy-associated glycoprotein (oPAG) and progesterone (P4) levels in the serum of Churra and Merino ewes throughout gestation and the first month post partum. The oPAG levels were determined with an heterologus RIA using bovine PAG as standard and tracer and rabbit antiserum against oPAG, sensitivity was 4.0 ng/ml. The P4 levels were measured with a radioimmunological procedure, including a specific extraction step with petroleum ether (bp 60–80°C) with a sensitivity of less than 0.1 ng/ml. There were no differences (P<0.10) in the oPAG profile between breeds from Weeks 1 to 18. From Week 18 to lambing, oPAG concentrations increased rapidly in Churra ewes (on average, from 250 to 650 ng/ml) while remaining relatively constant in the Merino ewes (around 250 ng/ml). No significant differences (P>0.05) were observed for mean weekly P4 levels between the 2 breeds. In both breeds, P4 increased throughout the whole length of gestation, with the highest level measured at Weeks 19–20, then declined 2 wk before parturition. No correlation was found between P4 and oPAG concentrations during gestation in either of the breeds. After lambing, oPAG and P4 levels decreased rapidly in 4 wk to basal values. In both breeds the oPAG concentrations at Weeks 19, 20 and 21 of gestation in ewes carrying male fetuses were higher than in those carrying female fetuses. From the results, we conclude that the breed and sex of the fetus could influence the production of oPAG. [less ▲]

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See detailMulti-Residue Screening and Confirmatory Analysis of Anabolic Steroids in Urine by Gas Chromatography Coupled with Tandem Mass Spectrometry
Van Vyncht, G.; Gaspar, P.; De Pauw, Edwin ULg et al

in Journal of Chromatography. A (1994), 683(1), 67-74

The diversity of substances used illegally as growth promoters in meat production requires the development of multi-analyte methods of analysis involving a sample pretreatment step that is as rapid and as ... [more ▼]

The diversity of substances used illegally as growth promoters in meat production requires the development of multi-analyte methods of analysis involving a sample pretreatment step that is as rapid and as easy as possible, followed by a specific and sensitive determination of several residues within the same run. A general strategy for the screening and confirmatory analysis of fifteen artificial anabolic compounds in urine samples is described. It is based on solid-phase extraction on C18 Empore discs and amino-bonded columns followed, after derivatization (trimethylsilyl or methyloxime-trimethylsilyl derivatives), by gas chromatography coupled with collisionally activated dissociation tandem mass spectrometry. [less ▲]

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See detailEfficiency of the sec-butyllithium/m-diisopropylbenzene diadduct as an anionic polymerization initiator in apolar solvents
Yu, Y. S.; Jérôme, Robert ULg; Fayt, Roger et al

in Macromolecules (1994), 27(21), 5957-5963

The 2/1 sec-butyllithium/1,3-diisopropenylbenzene adduct has been prepared and evaluated as an effective, hydrocarbon soluble, difunctional initiator for the synthesis of polystyrene-polybutadiene ... [more ▼]

The 2/1 sec-butyllithium/1,3-diisopropenylbenzene adduct has been prepared and evaluated as an effective, hydrocarbon soluble, difunctional initiator for the synthesis of polystyrene-polybutadiene-polystryene (SBS) thermoplastic elastomers in cyclohexane or benzene solution. The molecular weight distribution of both the PBD central block and the final block copolymer is narrow,and the expected molecular weight is obtained. However, mechanical testing, degradation of the PBD component, and use of an excess of s-BuLi compared to DIB suggest that the final copolymers are diblock instead of triblock as expected. The stoichiometric reaction of s-BuLi with DIB in an apolar solvent essentially results in the expected Li diadduct. This organolithium compound does not however react as a difunctional anionic initiator in a hydrocarbon solvent, but rather as a monofunctional compound more likely due to an association process. Addition of enough THF can make approximately two species active per DIB molecule. The addition of small amounts of triethylamine (<10 molecules per organolithium site) does not contribute to the formation of an acceptable difunctional initiator. The 1/1 addition of lithium tert-butoxide to the Li diadduct of DIB does not perturb the 1,4-microstructure of PBD, but it does not promote the activity of each metalated site of the initiator. [less ▲]

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See detailMacromolecular engineering of polylactones and polylactides. 17. Cryometric andviscosimetric analysis of the species active in the ring-opening polymerization of lactones, lactides, and cyclic anhydrides as initiated by aluminum triisopropoxide
Ropson, Nathalie; Dubois, Philippe; Jérôme, Robert ULg et al

in Macromolecules (1994), 27(27), 5950-5956

Al((OPr)-Pr-i)(3), which is one of the most efficient initiators for the living ring-opening polymerization (ROP) of lactones, lactides, and cyclic anhydrides, is known to be coordinatively associated in ... [more ▼]

Al((OPr)-Pr-i)(3), which is one of the most efficient initiators for the living ring-opening polymerization (ROP) of lactones, lactides, and cyclic anhydrides, is known to be coordinatively associated in apolar solvents. In the present study, the effect of cyclic monomers on the coordinative structure of Al((OPr)-Pr-i)(3) in benzene was investigated by cryometry. gamma-Butyrolactone (gamma-BL), a nonpolymerizable lactone, was first studied as a model monomer. The cryometric Job diagram for the gamma-BL/Al((OPr)-Pr-i)(3) system in benzene established formation of a trisolvated six-coordinate [Al((OPr)-Pr-i)(3).3 gamma-BL] complex. This is in perfect agreement with the hexacoordinated Al atoms as reported by Al-27 NMR. The extension of the cryometric study to a polymerizable lactone, e.g., delta-valerolactone (delta-VL), confirmed that the single [Al((OPr)-Pr-i)(3).3M] species is the actual initiator for the ring-opening polymerization. Al-27 NMR shows that the same conclusion holds when other cyclic monomers, such as lactides and glutaric anhydride, are considered. The induction period of time that is usually observed in the ROP of lactones, lactides, and cyclic anhydrides may now be attributed to the dissociation of the Al((OPr)-Pr-i)(3) aggregates upon the addition of the cyclic monomer. Toluene solutions of living poly(epsilon-CL) and polylactide chains as initiated by Al((OPr)-Pr-i)(3) were also investigated by viscosimetry. The mean association degree ((DA)) over bar of the living chains was calculated from the intrinsic viscosity compared to the value measured for the parent hydrolyzed and purified polyester. [less ▲]

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See detailHolliday junction cleavage by yeast Rad1 protein
Habraken, Yvette ULg; Sung, Patrick; Prakash, Louise et al

in Nature (1994), 371

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See detailComment je traite l'association hypertension artérielle et coronaropathie
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (1994), 49(10), 534-535

1. La coronaropathie s'observe fréquemment chez l'hypertendu , en partie suite à l'élévation de la pression artérielle, en partie suite à la constellation chez celui-ci de nombreux facteurs de risque d ... [more ▼]

1. La coronaropathie s'observe fréquemment chez l'hypertendu , en partie suite à l'élévation de la pression artérielle, en partie suite à la constellation chez celui-ci de nombreux facteurs de risque d'athérosclérose. 2. Son dépistage doit être systématique, utilisant diverses techniques non invasives au repos et à l'effort. L'état de la fonction ventriculaire gauche et l'épaisseur du myocarde doivent être appréciés. 3. Le traitement antihypertenseur vise à normaliser, progressivement, la pression artérielle, avec un seuil limite inférieur à ne pas dépasser lors de séquelle d'infarctus myocardique. 4. Le premier choix médicamenteux,si la fonction ventriculaire gauche est correcte, repose sur les Bêtabloquants. 5. Une alternative à ce choix est constituée par les antagonistes calciques ou, si le coeur est décompensé, les inhibiteurs de l'enzyme de conversion. 6. L'association de ces différents agents apporte un plus, souvent utile, par leurs actions complémentaires sur l'ischémie, l'hypertension artérielle, l'hypertrophie cardiaque tout en ayant un profil métabolique favorable. [less ▲]

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See detailA dusty nebula around the luminous blue variable candidate HD 168625
Hutsemekers, Damien ULg; van Drom, E.; Gosset, Eric ULg et al

in Astronomy and Astrophysics (1994), 290

On the basis of narrow-band visible and near-infrared imagery as well as high-resolution spectroscopy, we report the discovery of a new LBV-type nebula around the B supergiant HD 168625. We find that it ... [more ▼]

On the basis of narrow-band visible and near-infrared imagery as well as high-resolution spectroscopy, we report the discovery of a new LBV-type nebula around the B supergiant HD 168625. We find that it essentially consists of a dusty expanding shell from which seems to emerge a bipolar emission nebula, the whole embedded in a reflection nebulosity. The inner shell is stratified: the continuum emission arises beyond the ionized gas, and is possibly due to scattering of stellar light by large dust grains or to non-equilibrium dust emission. The unexpected presence of unidentified infrared emission bands (UIRs) in the spectrum of this object is also discussed. We finally report the non-detection of a comparable nebula around the nearby LBV HD 168607. [less ▲]

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See detailINCREASE IN LEVELS OF STRATOSPHERIC CHLORINE AND FLUORINE LOADING BETWEEN 1985 AND 1992
Gunson, M. R.; Abrams, M. C.; Lowes, L. L. et al

in Geophysical Research Letters (1994), 21(20), 2223-2226

Mixing ratios of 3.44 ppbv (parts per billion by volume) and 1.23 ppbv for HCl and HF above 50 km, surrogates for total chlorine and fluorine, have been measured by the Atmospheric Trace Molecule ... [more ▼]

Mixing ratios of 3.44 ppbv (parts per billion by volume) and 1.23 ppbv for HCl and HF above 50 km, surrogates for total chlorine and fluorine, have been measured by the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment on a March 1992 flight of the Space Shuttle. Compared to the measured values obtained on a 1985 flight, these correspond to a 37% and 62% increase for HCl and HF, respectively. The derived trend in HCl (similar to 0.13 ppbv per year) is in good agreement with the model-predicted increase in chlorine loading of 0.13 ppbv per year [Prather and Watson. 1990], and with the measured trends in HCl total column abundance from reported ground-based observations. The main source of this change can be attributed to the release of man-made chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). This new value for HCl represents an upper limit to the inorganic chlorine concentration in the stratosphere available for participation in photochemical processes which destroy ozone. [less ▲]

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See detailRole of Matrix, Fibroblasts and Type Iv Collagenases in Tumor Progression and Invasion
Noël, Agnès ULg; Emonard, H.; Polette, M. et al

in Pathology - Research & Practice (1994), 190(9-10), 934-41

We have studied the role of the extracellular matrix and host cells in tumor progression and tumor invasion. Our results emphasize the importance of tumoral cell-host cell interactions during this process ... [more ▼]

We have studied the role of the extracellular matrix and host cells in tumor progression and tumor invasion. Our results emphasize the importance of tumoral cell-host cell interactions during this process. Addition of human fibroblasts and/or basement membrane components to human mammary adenocarcinoma cells, when injected into athymic nude mice, results in an increase of take and growth rate of the tumors. Peritumoral extracellular matrix is remodeled through multiple mechanisms: overproduction of matrix components by fibroblasts, enhanced fibroblasts proliferation, modulation of interstitial collagenase production by fibroblasts and retraction of the matrix by tumoral cells. The degradation of basement membranes during the metastatic process is often associated with the secretion of proteolytic enzymes. The 72 kDa type IV collagenase, a metalloproteinase, can be produced by some tumoral cells. However, it appears also to be secreted by peritumoral stromal fibroblasts under the influence of tumoral cells. We have demonstrated the existence of a binding site for this enzyme on the membrane of mammary tumoral cells. These results suggest a cooperation between tumor cells and fibroblasts during basement membrane destruction. [less ▲]

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See detailRecognition and Treatment of Shingles
Nikkels, Arjen ULg; Pierard, Gérald ULg

in Drugs (1994), 48(4), 528-548

Varicella zoster virus (VZV) is responsible for a primary infection (varicella) followed by a latency, eventually resulting in herpes zoster (shingles). The replication cycle of VZV is normally ... [more ▼]

Varicella zoster virus (VZV) is responsible for a primary infection (varicella) followed by a latency, eventually resulting in herpes zoster (shingles). The replication cycle of VZV is normally interrupted after varicella. Consequently, VZV remains dormant in the organism. Reactivation occurs after viraemia, and the development of tissue alterations (skin and viscera) depends on the immunological status of the patient. Diagnosis of herpes zoster relies on clinical recognition and cytological and histological evaluations combined with immunohistochemistry and molecular biology techniques. Treatment of herpes zoster primarily relies upon antiviral drugs and incidentally on immunomodulating agents, specific immunoglobulins, antimicrobial agents, antiviral enzymes and corticosteroids. Drugs with a clinically relevant activity against varicella zoster virus infections include aciclovir, adenosine monophosphate, bromodeoxyuridine, desciclovir, fiacitabine, idoxuridine, interferon-alpha and vidarabine. Among them, aciclovir appears to be a first-line agent. Its efficacy has been well established by many clinical studies. Promising drugs for the future include famciclovir, penciclovir, valaciclovir and other molecules currently under investigation. Recent and promising improvements in antiviral drug development may increase patient compliance, cost-benefit ratios and therapeutic efficacy. [less ▲]

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See detailMesencephalic and third ventricle cysts: diagnosis and management in four cases.
RAMAEKERS, Vincent ULg; Reul, J.; Siller, V. et al

in Journal of neurology, neurosurgery, and psychiatry (1994), 57(10), 1216-20

Four infants with obstructive hydrocephalus caused by space occupying third ventricle and mesencephalic cysts are reported. Despite immediate shunt insertion in all patients, there was either lack of ... [more ▼]

Four infants with obstructive hydrocephalus caused by space occupying third ventricle and mesencephalic cysts are reported. Despite immediate shunt insertion in all patients, there was either lack of clinical improvement or late onset of clinical deterioration. Neuroimaging (CT, MRI, and ventriculography) diagnosed the presence of non-communicating midline outpouchings of the CSF pathways causing obstruction of aqueductal CSF flow and brainstem signs. The cysts were of different origin. In one patient it was caused by a previous thalamic haemorrhage, in another patient by neonatal Escherichia coli meningoventriculitis. In two cases with obstructive hydrocephalus at birth, the aetiology is unclear. Direct puncture and drainage of the cysts led to clinical improvement. The cysts were poorly visualised on CT and could be misinterpreted as an enlarged third ventricle, simulating congenital aqueduct stenosis. Careful neuroradiological investigation is necessary to establish an accurate diagnosis and neurosurgical management. In such cases with hydrocephalus and persisting ventricular enlargement despite shunting, CT ventriculography is a useful tool. [less ▲]

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See detailHigh-Dose Riboflavin as a Prophylactic Treatment of Migraine: Results of an Open Pilot Study
Schoenen, Jean ULg; Lenaerts, M.; Bastings, E.

in Cephalalgia : An International Journal of Headache (1994), 14(5), 328-9

If the brain of migraineurs is characterized between attacks by a reduction of mitochondrial phosphorylation potential, riboflavin, which has the potential of increasing mitochondrial energy efficiency ... [more ▼]

If the brain of migraineurs is characterized between attacks by a reduction of mitochondrial phosphorylation potential, riboflavin, which has the potential of increasing mitochondrial energy efficiency, might have prophylactic effects in migraine. In this preliminary open pilot study, 49 patients suffering from migraine (45 without aura, 4 with aura) were treated with 400 mg of riboflavin as a single oral dose for at least 3 months. Twenty-three patients received in addition 75 mg of aspirin. Mean global improvement after therapy was 68.2% and there was no difference between the two groups of patients. With the exception of one patient in the riboflavin plus aspirin group who withdrew because of gastric intolerance, no drug-related side effects were reported. High-dose riboflavin could thus be an effective, low-cost prophylactic treatment of migraine devoid of short-term side effects. A placebo-controlled trial of its efficacy seems worthwhile. [less ▲]

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See detailAcute Bronchial and Hematologic Effects Following Inhalation of a Single Dose of Paf. Comparison between Asthmatics and Normal Subjects
Louis, Renaud ULg; Bury, Thierry ULg; Corhay, Jean-Louis ULg et al

in CHEST (1994), 106(4), 1094-9

This study compared the acute bronchial and hematologic effects of inhaled platelet activating factor (PAF) (30 micrograms as a single dose) in 19 patients with mild asthma and 19 normal subjects. Each ... [more ▼]

This study compared the acute bronchial and hematologic effects of inhaled platelet activating factor (PAF) (30 micrograms as a single dose) in 19 patients with mild asthma and 19 normal subjects. Each subject underwent a methacholine bronchial challenge 1 week before PAF challenge to determine the concentration of methacholine causing a 20 percent fall in FEV1 (PC20M). On the day of PAF challenge, specific conductance (SGaw), FEV1, FEF25-75, and platelet and leukocyte counts were measured before, and 5, 10, 15, and 20 min after PAF inhalation. Changes in pulmonary and hematologic parameters were expressed as percent of control (saline solution/ethanol solution). Unlike normal subjects, subjects with asthma had bronchial hyperresponsiveness to methacholine: geometric mean (range): 0.59 mg/ml (0.07 to 9.8) vs > 32 mg/ml. Acute bronchial obstruction over the first 20 min after PAF inhalation was more pronounced in asthmatics than in normal subjects whatever the functional index considered (p < 0.01). In asthmatics (n = 19), mean (SEM) maximal fall in SGaw, FEV1, and FEF25-75 reached 50 percent (6), 11 percent (4), and 19 percent (5), respectively, while in normal subjects (n = 19) the maximal decreases were 24 percent (6), 4 percent (1), and 6 percent (1), respectively. In asthmatics, no correlation was found between log PC20M and log fall in FEV1 after PAF (r = 0.04 p > 0.05). In asthmatics and normal subjects, inhaled PAF caused a transient fall in neutrophils and monocytes by 5 min followed by a full recovery at 15 min and 20 min. These hematologic changes were not significantly different between the two groups. While not correlated with their airway responsiveness to methacholine, asthmatics, compared with normal subjects, develop an exaggerated acute airway obstruction in response to PAF. In contrast, hematologic changes induced by PAF do not differ between asthmatics and normal subjects. [less ▲]

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See detailDetermination of Benzodiazepines by Micellar Electrokinetic Chromatography
Bechet, I.; Fillet, Marianne ULg; Hubert, Philippe ULg et al

in Electrophoresis (1994), 15(10), 1316-21

A method for the separation and determination of benzodiazepines by micellar electrokinetic chromatography (MEKC) has been developed. Separation buffers consisted of aqueous solutions of glycine and ... [more ▼]

A method for the separation and determination of benzodiazepines by micellar electrokinetic chromatography (MEKC) has been developed. Separation buffers consisted of aqueous solutions of glycine and triethanolamine (pH 9.0), containing sodium dodecyl sulfate (SDS) as surfactant and methanol as organic modifier. The effect of the concentration of SDS, methanol, glycine and triethanolamine on migration times and resolution was studied. Ten benzodiazepines were baseline separated at a 25 mM SDS concentration and 20% v/v methanol in a 75 mM glycine-250 mM triethanolamine buffer. Under these conditions, the within-day reproducibilities were 0.3-0.5% for migration times and 1.7-1.9% for peak areas at a concentration of 10 micrograms/mL. The limits of detection and quantification for oxazepam were 0.2 and 0.7 micrograms/mL, respectively, using an injection time of 5 s. [less ▲]

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See detailAnalysis by in Situ Hybridization of Cytokine Mrna Expression in the Murine Developing Thymus
Deman, J.; Humblet, Chantal ULg; Martin, M. T. et al

in International Immunology (1994), 6(10), 1613-9

We have used in situ hybridization to investigate the expression of IL-1, IL-2, IL-4, IL-6 and IFN-gamma genes by thymic cells during fetal development in mice. Two waves of mRNAs were detected in thymic ... [more ▼]

We have used in situ hybridization to investigate the expression of IL-1, IL-2, IL-4, IL-6 and IFN-gamma genes by thymic cells during fetal development in mice. Two waves of mRNAs were detected in thymic cells for IL-1 at days 16 and 19 of gestation, for IL-2 at days 14 and 18, and for IL-4 at days 14 and 16. Three peaks for IL-6 were observed at days 13, 17 and around birth. Finally, only one peak of cells positive for IFN-gamma was detected. Whereas cells positive for IL-1 were generally grouped and more often localized in the external area of the thymus, the other positive cells were isolated and evenly distributed in the thymus. Our results illustrated the presence of cytokine transcripts in the developing thymus following a developmentally controlled sequence and support the hypothesis that cytokines could play a role in T cell development. [less ▲]

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See detailMolecular Structures of Penicillin-Binding Proteins and Beta-Lactamases
Ghuysen, Jean-Marie ULg

in Trends in Microbiology (1994), 2(10), 372-380

In the past, new antibacterial agents have been selected either from natural sources or by 'trial and error' modification of existing antibacterials. Future therapeutic strategies are likely to depend on ... [more ▼]

In the past, new antibacterial agents have been selected either from natural sources or by 'trial and error' modification of existing antibacterials. Future therapeutic strategies are likely to depend on increased knowledge of existing drug targets and the search for new targets. The machinery for the assembly of bacterial-cell-wall peptidoglycan is an ideal place to look. [less ▲]

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See detailDevelopment of a Database System for the Management of Borehole Data : Experience and lessons
Halleux, Isabelle ULg

in Mathematical Geology (1994), 26(7), 833-841

CBS-LOG is a multilingual database system for the management of coal exploratory borehole data. It is a dBase application running on PC's with minimum configurations. Developing a suitably accurate ... [more ▼]

CBS-LOG is a multilingual database system for the management of coal exploratory borehole data. It is a dBase application running on PC's with minimum configurations. Developing a suitably accurate database requires some stratégic choices and lots of discussions and compromises between experts. The experience shows that it is absolutely necessary to follow strictly the development flow-sheet and that the difficulties rely mainly on communication and human aspects of mathematical geology. A step by step approach is reviewed in terms of experience and lessons. [less ▲]

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See detailPropofol Protects Cultured Rat Hippocampal Neurons against N-Methyl-D-Aspartate Receptor-Mediated Glutamate Toxicity
Hans, Pol ULg; Bonhomme, Vincent ULg; Collette, Julien ULg et al

in Journal of Neurosurgical Anesthesiology (1994), 6(4), 249-53

The effect of propofol on the toxicity induced by glutamate (GLU), N-methyl-D-aspartate (NMDA), kainate (KA), and amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) was investigated on cultured ... [more ▼]

The effect of propofol on the toxicity induced by glutamate (GLU), N-methyl-D-aspartate (NMDA), kainate (KA), and amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) was investigated on cultured fetal rat hippocampal neurons. The degree of neuronal injury was quantified by measuring the release of the neuron-specific enolase (NSE) into the culture media. The toxicity induced by brief exposure to GLU (10(-4) M) or to NMDA (10(-4) M) was significantly reduced by propofol, whereas that elicited by KA, AMPA (10(-4) M), or long GLU exposure was unaffected. In conclusion, high concentrations of propofol significantly attenuate NMDA receptor-mediated glutamate neurotoxicity in vitro. Further studies are needed to confirm this beneficial effect in vivo and to evaluate propofol as a neuroprotective anesthetic agent in pathologies involving glutamate release and NMDA-mediated toxicity. [less ▲]

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See detailFast determination of myoglobin in serum using a new radial partition immunoassay
Chapelle, Jean-Paul ULg; Lemache, K.; el Allaf, M. et al

in Clinical Biochemistry (1994), 27(5), 423-8

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See detailSynthesis and characterization of biodegradable homopolymers and block copolymers based on 1,5-dioxepan-2-one
Löfgren, Anders; Albertsson, Ann-Christine; Dubois, Philippe et al

in Macromolecules (1994), 27

Homopolymers of 1,5-dioxepan-2-one (DXO) and block copolymers of DXO and epsilon-caprolactone (epsilon-CL) have been synthesized with aluminum isopropoxide as an initiator in toluene and tetrahydrofuran ... [more ▼]

Homopolymers of 1,5-dioxepan-2-one (DXO) and block copolymers of DXO and epsilon-caprolactone (epsilon-CL) have been synthesized with aluminum isopropoxide as an initiator in toluene and tetrahydrofuran (THF). The homopolymerization is first order with respect to both monomer and initiator, and the end-group analysis agrees with a coordination insertion mechanism based on the acyl-oxygen cleavage of the DXO ring. Living poly(epsilon-caprolactone) (PCL) and poly(1,5-dioxepan-2-one) (PDXO) chains are very efficient macroinitiators for the polymerization of DXO and epsilon-CL, respectively, with formation of block copolymers of a narrow molecular weight distribution. Size-exclusion chromatography (SEC) and C-13 NMR confirm the blocky structure of the copolymers, in agreement with DSC that show a melting endotherm for the PCL block and two glass transitions characteristic of the amorphous phases of PDXO and PCL. Because of the crystallinity of the PCL block (T(m) = 60-degrees-C) and the low glass transition temperature of the amorphous PDXO block (T(g) = -39-degrees-C), poly(epsilon-CL-b-DXO-b-epsilon-CL) triblocks have the potential of thermoplastic elastomers. Block copolymers of epsilon-CL and DXO are also sensitive to hydrolysis which makes them possible candidates for biomedical applications. Initiation of the DXO polymerization with functional diethylaluminum alkoxides is also discussed. [less ▲]

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See detailProfiles of stratospheric chlorine nitrate (ClONO2) from atmospheric trace molecule spectroscopy/ATLAS 1 infrared solar occultation spectra
Rinsland, Curtis P.; Gunson, M. R.; Abrams, M. C. et al

in Journal of Geophysical Research (1994), 99(D9), 18895-18900

Stratospheric volume mixing ratio profiles of chlorine nitrate (ClONO2) have been retrieved from 0.01-cm−1 resolution infrared solar occultation spectra recorded at latitudes between 14°N and 54°S by the ... [more ▼]

Stratospheric volume mixing ratio profiles of chlorine nitrate (ClONO2) have been retrieved from 0.01-cm−1 resolution infrared solar occultation spectra recorded at latitudes between 14°N and 54°S by the atmospheric trace molecule spectroscopy Fourier transform spectrometer during the ATLAS 1 shuttle mission (March 24 to April 2, 1992). The results were obtained from nonlinear least squares fittings of the ClONO2 v 4 band Q branch at 780.21 cm−1 with improved spectroscopic parameters generated on the basis of recent laboratory work. The individual profiles, which have an accuracy of about ±20%, are compared with previous observations and model calculations. [less ▲]

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See detailEffects of Steroidal and Non Steroidal Aromatase Inhibitors on Sexual Behavior and Aromatase-Immunoreactive Cells and Fibers in the Quail Brain
Foidart, Agnès ULg; Harada, N.; Balthazart, Jacques ULg

in Brain Research (1994), 657(1-2), 105-23

Castrated quail were treated with Silastic implants filled with testosterone (T) in association with injections of the aromatase inhibitors, R76713 (racemic vorozole; 1 mg/kg twice a day) or 4 ... [more ▼]

Castrated quail were treated with Silastic implants filled with testosterone (T) in association with injections of the aromatase inhibitors, R76713 (racemic vorozole; 1 mg/kg twice a day) or 4-hydroxyandrostenedione (OHA; 5 mg/bird twice a day). [less ▲]

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See detailModulation of Temporalis Muscle Exteroceptive Suppression by Limb Stimuli in Normal Man
Schoenen, Jean ULg; Wang, W.; Gérard, P.

in Brain Research (1994), 657(1-2), 214-20

The effects of noxious and non-noxious limb stimulations on the second exteroceptive suppression of voluntary temporalis muscle activity (ES2) were studied in healthy human volunteers. Duration of ... [more ▼]

The effects of noxious and non-noxious limb stimulations on the second exteroceptive suppression of voluntary temporalis muscle activity (ES2) were studied in healthy human volunteers. Duration of temporalis ES2 was measured on averaged rectified responses obtained after stimulating the labial commissure at an intensity of 25 mA. Single peripheral electrical stimuli applied over nerve trunks or over the skin before the labial stimulus decreased ES2 duration. This effect was most pronounced after cutaneous stimuli, especially of the index finger, and it was not observed when the conditioning stimulus was a 10 second, high frequency train. For stimulation at the index finger, temporalis ES2 inhibition progressively increased with intensity from 10 mA to 40 mA; it was maximal for an interstimulus interval between 50 and 140 ms. After naloxone (0.4 mg or 4 mg, i.v.) there was a partial reversal of the index-induced ES2 depression, but this effect was not significant. Immersion of one hand in water heated at 47 degrees C produced a short-lasting ES2 reduction. These results are comparable, though not similar, to the inhibition of the digastric reflex (or jaw opening reflex) observed in animals after limb stimuli and to the depression of the spinal flexion reflex reported in man after heterotopic peripheral stimuli. Although peripheral stimuli were able by themselves to suppress temporalis EMG activity in some subjects, it is likely that they reduce labial-induced ES2 via activation of brainstem structures, such as periaqueductal gray matter or raphe magnus nucleus, which are thought to inhibit the medullary inhibitory interneurons mediating ES2. [less ▲]

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See detailErratum for : primary structure of the streptomyces R61 extracellular DD-peptidase. 1. Cloning into Streptomyces lividans and nucleotide sequence of the gene
Duez, Colette ULg; Piron-Fraipont, C.; Joris, Bernard ULg et al

in European Journal of Biochemistry (1994), 224(3), 1079

This is the correction of the fig. 5 of Primary structure of the Streptomyces R61 extracellular DD-peptidase. 1. Cloning into Streptomyces Zividuns and nucleotide sequence of the gene, by C. Duez, C ... [more ▼]

This is the correction of the fig. 5 of Primary structure of the Streptomyces R61 extracellular DD-peptidase. 1. Cloning into Streptomyces Zividuns and nucleotide sequence of the gene, by C. Duez, C. Piron-Fraipont, B. Joris, J. Dusart, M. S. Urdea, J. A. Martial, J.-M. Frère and J.-M. Ghuysen. European Journal of Biochemistry Volume 162, Issue 3, pages 509–518, February 1987 [less ▲]

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See detailDifferentiation Ability and Oncogenic Potential of Hpv-33- and Hpv-33 + Ras-Transfected Keratinocytes
Gilles, Christine ULg; Piette, Jacques ULg; Peter, W. et al

in International Journal of Cancer = Journal International du Cancer (1994), 58(6), 847-54

Five HPV-33-immortalized and 5 HPV-33 + ras-transfected cell lines were characterized in terms of growth in soft agar, tumorigenic potential in nude mice, p21 expression, morphology and expression of ... [more ▼]

Five HPV-33-immortalized and 5 HPV-33 + ras-transfected cell lines were characterized in terms of growth in soft agar, tumorigenic potential in nude mice, p21 expression, morphology and expression of differentiation markers in organotypic cultures. No striking differences were observed between the HPV-33-immortalized cell lines and their corresponding ras-transfected counterparts as regards their tumorigenicity in nude mice (only one cell line was able to develop tumors in nude mice) or their behavior on lifted collagen gels. However, all the ras-transfected cell lines gave rise to colonies in soft agar while only 2 HPV-33-transfected lines (CK1 and CK4) displayed this property. The 10 cell lines could be divided into 2 groups with respect to their phenotype in monolayer and in organotypic cultures. Lines from group I (CK2, 3, 5 and their ras-transfected homologous lines) shared a typical epithelial phenotype in monolayer and the ability (a) to form an epithelium similar to a CIN-III lesion and (b) to strongly express keratins K1-K10 and involucrin in organotypic cultures. On the other hand, for the lines from group II (CK1, CK4, CK1EJ7 and CK4EJ5), there was a correlation between an elongated phenotype in monolayer and the property (a) to form a structure similar to a microinvasive carcinoma and (b) to express vimentin and keratins K8-K18. These cell lines, exhibiting various transformation-associated alterations, can be considered as an in vitro model representing various stages of HPV-33-associated cervical carcinogenesis. [less ▲]

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See detailSynergistic Control by Androgens and Estrogens of Aromatase in the Quail Brain
Balthazart, Jacques ULg; Stoop, R.; Foidart, Agnès ULg et al

in Neuroreport (1994), 5(14), 1729-32

Castrated quail were injected with testosterone or with the synthetic hormones diethylstilbestrol (DES) or methyltrienolone (R1881) to analyse the steroid specificity in the induction of brain aromatase ... [more ▼]

Castrated quail were injected with testosterone or with the synthetic hormones diethylstilbestrol (DES) or methyltrienolone (R1881) to analyse the steroid specificity in the induction of brain aromatase. R1881 produced a moderate (generally non-significant) increase in the number of aromatase-immunoreactive cells. DES significantly increased the number of positive cells in most brain areas. A clear synergism between DES and R1881 was observed in all brain regions: more immunoreactive cells were found in birds receiving both compounds than in those injected with DES or R1881 alone. DES and R1881 are highly specific ligands for oestrogen and androgen receptors respectively. It appears likely that both androgens and oestrogens directly modulate brain aromatase, presumably at the transcription level. [less ▲]

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See detailMagnetic ordering in U2Pd2In and U2Pd2Sn
Purwanto, A.; Robinson, R. A.; Havela, Ladislav et al

in Physical Review. B : Condensed Matter (1994), 50(10), 6792-6801

The tetragonal intermetallic compounds U2Pd2In and U2Pd2Sn have been studied by means of magnetic susceptibility, magnetization, specific heat, electrical resistivity, and x-ray- and neutron-diffraction ... [more ▼]

The tetragonal intermetallic compounds U2Pd2In and U2Pd2Sn have been studied by means of magnetic susceptibility, magnetization, specific heat, electrical resistivity, and x-ray- and neutron-diffraction techniques. The compounds order antiferromagnetically at 36 and 41 K, respectively, and have enhanced electronic specific-heat coefficients γ of 393 and 203 mJ/mol f.u. K**2, respectively. At low temperature, the nearest-neighbor U-U spacing is along the c axis in both compounds, though in U2Pd2Sn the in-plane U-U distance is shorter at room temperature. This crossover is due to motion of the U atoms within the cell rather than anisotropy of the thermal contraction. It is now well established in several classes of (1:1:1) uranium ternary intermetallic compounds that the strong magnetic anisotropy is correlated with the direction of nearest-neighbor U-U links; the moments are almost invariably oriented perpendicular to such links. This is also the case for U2Pd2In and U2Pd2Sn, where the moments lie in the tetragonal basal plane in a canted arrangement along [110] and [1¯10] directions. Of four such Shubnikov subgroups of P4/mbm, one is clearly preferred by the data. At 10 K, the magnetic moments extracted are (1.6±0.2) Bohr magneton and (2.0±0.1) Bohr magneton per U atom in U2Pd2In and U2Pd2Sn, respectively. [less ▲]

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See detailComment je traite un patient hypertendu diabétique de type II
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (1994), 49(9), 473-474

1. Les patients diabétiques de type II se caractérisent par une prévalence élevée d'hypertension artérielle avec ses conséquences vasculaires sous-tendues par l'insulinorésistance. 2. Le traitement de l ... [more ▼]

1. Les patients diabétiques de type II se caractérisent par une prévalence élevée d'hypertension artérielle avec ses conséquences vasculaires sous-tendues par l'insulinorésistance. 2. Le traitement de l'hypertension artérielle constitue une mesure importante de prévention des complications cardiovasculaires, à côté de la correction d'une dyslipémie, de l'arrêt du tabagisme et de l'équilibre glycémique. 3. L'approche non pharmacologique constitue une première étape obligée mais efficace. 4. Le niveau de pression artérielle à atteindre est inférieur à 130/85 mmHg chez ce type de patient. 5. Le traitement médicamenteux est difficile, lié au risque accru d'effets métaboliques et vasculaires secondaires. 6. Les inhibiteurs de l'enzyme de conversion, les antagonistes calciques et les nouveaux bêtabloquants à propriété vasodilatatrice constituent un excellent premier choix. L'âge et d'éventuelles complications athéroscléreuses, déjà présentes au moment du traitement, orientent ce choix. [less ▲]

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See detailMesure ambulatoire de la pression artérielle, son utilité en pratique quotidienne
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (1994), 49(9), 475-480

Si la nécessité du traitement de l'hypertension artérielle est un fait accepté de façon universelle, la question à propos des niveaux de pression artérielle qui méritent une intervention reste débattue ... [more ▼]

Si la nécessité du traitement de l'hypertension artérielle est un fait accepté de façon universelle, la question à propos des niveaux de pression artérielle qui méritent une intervention reste débattue. Cette difficulté trouve son origine dans une telle variabilité de la pression artérielle que les mesures au cabinet de consultation représentent seulement une vue limitée de son réel profil sur 24 heures. Le développement d'enregistreurs portatifs de la pression artérielle par méthode non invasive a permis d'étudier la variabilité remarquable de cette pression artérielle tout au long des activités habituelles des patients. Bien que cette technique de mesure ambulatoire de la pression artérielle (MAPA) ne remplace pas la mesure traditionnelle de la pression artérielle, elle s'impose de plus en plus comme complément indispensable et non invasif dans certaines indications cliniques spécifiques (hypertensions de la blouse blanche, limite, réfractaire, ou encore vérification de l'efficacité du contrôle tensionnel). [less ▲]

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See detailMoabs Mas516 and 5b5, Two Fibroblast Markers, Recognize Human Follicular Dendritic Cells
Bosseloir, A.; Heinen, Ernst ULg; Defrance, T. et al

in Immunology Letters (1994), 42(1-2), 49-54

Follicular dendritic cells (FDC) are only located within follicles of secondary lymphoid tissues. The origin of this peculiar cell type is not clearly defined. To contribute to this study, we applied two ... [more ▼]

Follicular dendritic cells (FDC) are only located within follicles of secondary lymphoid tissues. The origin of this peculiar cell type is not clearly defined. To contribute to this study, we applied two monoclonal antibodies (MAS516 and 5B5) considered as specific for fibroblasts to tonsil cryosections and to isolated follicular dendritic cells. On the basis of an enzyme cocktail digestion of human tonsils and a fractionation procedure on albumin gradients, FDC can be prepared in the form of cell aggregates with associated lymphoid cells. MAS516 reacts with surface membrane molecules expressed by human fibroblasts, tissue macrophages and peripheral blood monocytes. With immunoperoxidase assays on tonsil cryosections connective tissue cells and macrophages are stained. Inside germinal centres, heavy labelling of the light zone was found. The MAS516 staining pattern is very similar to that of specific FDC markers DRC-1 or BU10. All isolated FDC reacted with MAS516 antibody. 5B5, considered as a typical fibroblast marker, reacts with human prolyl-4-hydroxylase which is an intracellular enzyme related to collagen biosynthesis. In cryosections, interfollicular and capsular areas showed 5B5 positive connective tissue fibroblasts. In germinal centres, some cells presenting features of FDC were 5B5 positive. After cell separation, 25%-50% of the isolated FDC were labelled with this antibody. This positivity of some FDC for 5B5 antibody may support the idea of their fibroblastic origin. The combination of observations realized in situ and after cell purification ensured an unequivocal recognition and identification of FDC.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailLa prothèse pénienne: Contrariétés d'une virilité artificielle
Kempeneers, Philippe ULg; Andrianne, R.; Mormont, Christian ULg

in Sexologies (1994), 3(13), 26-30

Au cours d'une enquête de follow-up réalisée auprès de 25 patients implantés, nous avons constaté, en filigrane des réponses fournies par les sujets, un sentiment de malaise, voire d'humiliation lié à l ... [more ▼]

Au cours d'une enquête de follow-up réalisée auprès de 25 patients implantés, nous avons constaté, en filigrane des réponses fournies par les sujets, un sentiment de malaise, voire d'humiliation lié à l'usage d'une prothèse pénienne. Chez l'humain, l'érection comporte une valeur symbolique incontestable. Mise à mal par l'impuissance, l'image virile de l'homme ne se restaure pas entièrement avec l'installation d'une prothèse pénienne.Solution artificielle, celle-ci semble laisser subsister chez de nombreux patients des difficultés psychologiques à assumer la perte définitive de leurs capacités naturelles d'érection. [less ▲]

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See detailQuantitative Assessment of the Specific Cd4+ T Lymphocyte Proliferative Response in Bovine Herpesvirus 1 Immune Cattle
Denis, M.; Kaashoek, M. J.; van Oirschot, J. T. et al

in Veterinary Immunology and Immunopathology (1994), 42(3-4), 275-86

We quantified the CD4+ T cell proliferation specific for bovine herpesvirus 1 (BHV-1) in peripheral blood mononuclear cells from cattle. The stimulation index as detected in proliferative assays performed ... [more ▼]

We quantified the CD4+ T cell proliferation specific for bovine herpesvirus 1 (BHV-1) in peripheral blood mononuclear cells from cattle. The stimulation index as detected in proliferative assays performed in the presence of BHV-1 antigen is highly variable in immune cattle. By using proliferative assays performed after negative selection we showed that, as expected, CD4+ T cells were the limiting cell type for antigen-induced proliferation. Neither B, gamma delta T nor CD8+ cells seemed to be involved. The limiting dilution method was established to obtain quantitative estimations, namely frequencies of specific T cells. When limiting dilution cultures were supplemented with interleukin-2 (IL-2), an IL-2 induced unspecific cell proliferation masked the specific T cell proliferation. Natural killer cells were not the major cell type involved, but CD4+ lymphocytes themselves seemed to respond to IL-2 irrespective of the presence of antigen. When cultures were performed without addition of IL-2, the frequency of BHV-1 specific proliferative T cells could be obtained by the difference between the frequency of proliferating cells calculated in the presence and absence of antigen. The method provides a sensitive and quantitative means to measure the T cell immune response to BHV-1 vaccine candidates. [less ▲]

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See detailLe management à l'aube du XXI siècle
Choffray, Jean-Marie ULg; Tarondeau, Jean-Claude; Jolibert, Alain

in Revue Française de Gestion (1994)

Cet article présente les résultats d'une enquête menée auprès d'un échantillon de dirigeants des plus grandes entreprises françaises, dont l'objet est d'évaluer les principales transformations qui ont ... [more ▼]

Cet article présente les résultats d'une enquête menée auprès d'un échantillon de dirigeants des plus grandes entreprises françaises, dont l'objet est d'évaluer les principales transformations qui ont affecté le management depuis vingt ans, et de s'interroger sur les innovations à venir. [less ▲]

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See detailPreservation of Cortical Microcirculation after Kidney Ischemia-Reperfusion: Value of an Iron Chelator
Defraigne, Jean-Olivier ULg; Pincemail, Joël ULg; Detry, Olivier ULg et al

in Annals of Vascular Surgery (1994), 8(5), 457-67

Treatment of suprarenal aneurysms and renal artery reconstructions are both responsible for normothermic ischemia of the kidney (during clamping) followed by reperfusion (declamping). During reflow ... [more ▼]

Treatment of suprarenal aneurysms and renal artery reconstructions are both responsible for normothermic ischemia of the kidney (during clamping) followed by reperfusion (declamping). During reflow through an organ undergoing ischemia the production of free radicals can be associated with cell injury and a no-reflow phenomenon characterized by perfusion defects after a period of transient hyperemia. The objectives of this study were to demonstrate the existence of this phenomenon in the kidney undergoing ischemia followed by reperfusion and to test the potential protection afforded by an iron chelator (desferrioxamine) since free radical reactions are catalyzed by iron. Adult New Zealand white rabbits were divided into the following three groups: group A, 15 minutes of ischemia plus 10 minutes of reperfusion; group B, 60 minutes of ischemia plus 10 minutes of reperfusion; and group C, 60 minutes of ischemia plus 10 minutes of reperfusion combined with infusion of desferrioxamine (50 mg/kg). Cortical microcirculation in the kidney was measured by laser Doppler flowmeter before ischemia and 1, 5, and 10 minutes after reperfusion. Vitamin E content was determined in the cortex of the left kidney after 10 minutes of reperfusion and compared with that of the right (control) kidney. After 1 minute of reperfusion the cortical microcirculatory flow was significantly increased in all three groups (reactive hyperemia). In groups A and C blood flow returned to preclamping values after 10 minutes of reperfusion; however, blood flow in group B remained significantly reduced (29.2% +/- 10.5%) after 5 minutes of reperfusion with a further reduction to 48.5% +/- 5.7% after 10 minutes. These findings were correlated with the dosage of vitamin E since the vitamin E content was greatly reduced by 46.7% +/- 7.8% in group B but did not change significantly in groups A and C. This study shows that 60 minutes of normothermic ischemia is followed by a significant reduction in cortical microcirculatory flow (no-reflow phenomenon). Infusion of an iron chelator (desferrioxamine), however, which decreases the intensity of lipid peroxidation induced by the free radicals, preserves the microcirculatory flow. [less ▲]

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See detailThe identification of 16O 18O 16O and 16O 16O 18O ozone isotopes in high resolution ground-based FTIR spectra
Arlander, Dixon William (Bill); Barbe, Alain; Bourgeois, M.T. et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (1994), 52(3-4), 267271

We present evidence of the 16O 18O 16O and 16O 16O 18O ozone isotopes in the 5 μ region from FTIR solar occultation spectra obtained from the Jungfraujoch Solar Observatory (47°N, 8°E, 3580 m) in ... [more ▼]

We present evidence of the 16O 18O 16O and 16O 16O 18O ozone isotopes in the 5 μ region from FTIR solar occultation spectra obtained from the Jungfraujoch Solar Observatory (47°N, 8°E, 3580 m) in Switzerland at a spectral resolution of 0.0025 cm-1 (res.=1/2L). These spectra clearly show numerous unblended lines of the 16O 18O 16O ozone isotope. Laboratory spectra in the 5 μ region of both 50O3 isotopes have been measured and have yielded line positions of the v1+v3 isotopic bands which can eventually lead to their retrieval from measured ground-based solar occulation spectra. Although retrieval of 16O 16O 18O could be difficult due to slight line blending, identification of several lines is shown. [less ▲]

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See detailDramatic improvement of severe dilated cardiomyopathy in an acromegalic patient after treatment with octreotide and trans-sphenoidal surgery.
Legrand, Victor ULg; Beckers, Albert ULg; Pham, V. T. et al

in European Heart Journal (1994), 15(9), 1286-9

Severe congestive heart failure developed in an acromegalic patient, and was successfully treated with octreotide followed by trans-sphenoidal surgery. Clinical, hormonal echocardiographic and ... [more ▼]

Severe congestive heart failure developed in an acromegalic patient, and was successfully treated with octreotide followed by trans-sphenoidal surgery. Clinical, hormonal echocardiographic and haemodynamic findings as well as histological heart examination before and after treatment revealed that over-production of growth hormone may induce the myocardial cell degeneration responsible for mechanical heart dysfunction. In addition, this unique example demonstrates the reversibility of myocardial damage following octreotide and trans-sphenoidal surgery, leading to significant improvement in cardiac function with minimal diastolic dysfunction and moderate interstitial fibrosis. [less ▲]

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See detailDirect Evidence of Free Radical Production after Ischaemia and Reperfusion and Protective Effect of Desferrioxamine: Esr and Vitamin E Studies
Defraigne, Jean-Olivier ULg; Detry, Olivier ULg; Pincemail, Joël ULg et al

in European Journal of Vascular Surgery (1994), 8(5), 537-43

After surgical renal revascularisation, warm renal ischaemia due to renal artery cross-clamping contributes to postoperative renal dysfunction. After reperfusion, free radicals are thought to be a ... [more ▼]

After surgical renal revascularisation, warm renal ischaemia due to renal artery cross-clamping contributes to postoperative renal dysfunction. After reperfusion, free radicals are thought to be a significant cause of injury. Nevertheless, indisputable proof of free radical production is scarce, partly because of their transient nature. In this study, electron paramagnetic resonance and vitamin E levels were used to demonstrate the free radical production after renal ischaemia and reperfusion. Rabbit kidneys were submitted either to 15 or 60 minutes of ischaemia followed by reperfusion. A spin trap agent (alpha-phenyl-N-tert-butyl nitrone (PBN), 20mg/ml, 1 ml/min) was infused during reperfusion directly into the left renal artery via an aortic catheter before declamping. Blood samples were selectively drawn from the left renal vein for ESR analysis (Varian spectrometer E109) of lipidic residues extracted from blood samples. The vitamin E content of the left renal cortex was determined by HPLC procedure. The right renal cortex was used as a control for the vitamin E values. In the venous effluent, ESR analysis revealed the formation of a spectrum consisting of a triplet of asymmetric doublets. This signal resulted from the spin trapping by PBN of a mixture of both oxygen- and carbon- centred lipidic radicals. The amplitude of the signal which is proportional to the amount of free radicals was significantly higher after 60 minutes ischaemia than after 15 minutes.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailModulation of Immunological Histamine Release from Human Lung Fragments by Stem Cell Factor, Il-3, Il-5 and Gm-Csf: Comparison with Human Leukocytes
Louis, Renaud ULg; Dowlati, A.; Weber, T. et al

in International Archives of Allergy & Immunology (1994), 105(1), 18-25

Because of the importance of cytokines in the regulation of allergic inflammation, we investigated the effects of SCF, IL-3, IL-5 and GM-CSF on immunological histamine release from sensitized human lung ... [more ▼]

Because of the importance of cytokines in the regulation of allergic inflammation, we investigated the effects of SCF, IL-3, IL-5 and GM-CSF on immunological histamine release from sensitized human lung fragments as well as human leukocytes. SCF (0.2-20 ng/ml) caused a concentration-related enhancement of anti-IgE (1/100) induced histamine release from lung fragments reaching maximally 64% at 20 ng/ml. In contrast, enhancement produced by IL-5, IL-3 and GM-CSF (0.2-20 ng/ml) was quite marginal and reached at best around 20% at the higher concentration, IL-5 being slightly more effective than IL-3 and GM-CSF. Further, SCF potentiated histamine release whatever the level of immunological control whereas potentiation by IL-5 primarily occurred when the amount of histamine release induced by the immunological control ranged between 5 and 10%. SCF acted synergistically with IL-5, producing a greater enhancement of histamine release than the sum of each cytokine used alone. Both SCF and, to a lesser extent, IL-5 potentiated anti-IgE-mediated histamine release regardless of passive sensitization of lung fragments. Unlike what was observed with lung fragments, IL-3, GM-CSF and to a lesser extent IL-5, were potent enhancing agents of anti-IgE (1/2,000)-induced histamine release from leukocytes. Maximal enhancement produced by IL-3 (20 ng/ml), GM-CSF (2 ng/ml) and IL-5 (20 ng/ml) reached 92%, 78% and 61%, respectively. By contrast, SCF (0.2-20 ng/ml) was ineffective on human leukocytes.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailCompte rendu de « Robert SACRÉ, Les Negro Spirituals et les Gospel Songs, Paris, P.U.F. (Que sais-je ? 2791), 1993 »
Pirenne, Christophe ULg

in Bulletin de la Société liégeoise de Musicologie (1994), 86

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See detailDecrease of T-Lymphocyte Proliferation in Exercise-Induced Asthma
Bury, Thierry ULg; Corhay, Jean-Louis ULg; Louis, Renaud ULg et al

in Allergy (1994), 49(8), 605-10

The present study was designed to examine the effect of physical exercise on T-lymphocyte proliferation in patients with exercise-induced asthma (EIA). Indeed, a decrease in different immune functions is ... [more ▼]

The present study was designed to examine the effect of physical exercise on T-lymphocyte proliferation in patients with exercise-induced asthma (EIA). Indeed, a decrease in different immune functions is described in normal man after exercise. Thirty subjects (10 normal and 20 asthmatic subjects with or without EIA) underwent a submaximal exercise test on an electrically driven treadmill. Before and after this test, ventilatory variables were measured, and venous blood was taken to study plasma histamine (RIA) and spontaneous and phytohemagglutinin (PHA)-pulsed T-lymphocyte proliferation (mononuclear cells isolated on Ficoll-Hypaque; tritiated thymidine incorporation). Ten minutes after the end of the exercise, there was a significant FEV1 decrease only in asthmatic subjects with EIA (mean: 24 +/- 5%). In the same group, the mean plasma histamine level was 0.31 ng/ml-1 (+/- 0.06) before the challenge. It rose to 0.62 ng/ml-1 (+/- 0.14) 10 min after the end of the exercise (P < 0.05), and returned to normal limits 20 min after the test. In this group, there was also a significant decrease (by about 35%) of spontaneous and PHA-pulsed T-lymphocyte proliferation 2 and 4 h after the exercise. By contrast, exercise challenge had no effect on either plasma histamine level or T-lymphocyte proliferation in the normal group. Our results show a rapid and transient increase in plasma histamine in EIA. This was followed 2 and 4 h later by a significant decrease of T-lymphocyte proliferation. A possible relationship between these two phenomena is discussed. [less ▲]

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See detailCytokine Modulation of Basophil Histamine Release in Wasp-Venom Allergy
Radermecker, Maurice ULg; Louis, Renaud ULg; leclercq, M. et al

in Allergy (1994), 49(8), 641-4

We report the effect of interleukin-3 (IL-3) and of other cytokines on antigen-induced basophil histamine release in wasp-venom-allergic subjects. Leukocytes from 12 patients with documented anaphylactic ... [more ▼]

We report the effect of interleukin-3 (IL-3) and of other cytokines on antigen-induced basophil histamine release in wasp-venom-allergic subjects. Leukocytes from 12 patients with documented anaphylactic sensitivity to wasp venom were preincubated in the presence or absence of IL-3, granulocyte/macrophage-colony stimulating factor (GM-CSF), IL-5, IL-8, or stem cell factor (SCF). Washed cells were then exposed to venom and to other secretagogues, and histamine release in the supernatant was measured fluorometrically. Preincubation of leukocytes with IL-3, GM-CSF, or IL-5 (0.02-2 ng/ml), but not with IL-8 and SCF, caused a dose-dependent enhancement of antigen-induced basophilic histamine release in all subjects tested. Mean maximum increase was about 100% for IL-3, IL-5, and GM-CSF. The priming effect of IL-3 was rapid, persisted up to 12 h, and was not accompanied by a change in cellular histamine. IL-3 had a comparable enhancing effect when basophils were triggered with anti-IgE or N-formylmethionylphenylalanine (FMP). By contrast, IL-3 had no effect on substance-P-induced histamine release. The significant enhancement of basophil releasability to antigen in wasp-venom allergy by very low concentrations of IL-3, GM-CSF, and IL-5 suggests that cytokines in the basophil (mast-cell?) microenvironment could be critical factors in determining the variability of sting reactions in Hymenoptera-venom-allergic subjects. [less ▲]

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See detailThe Precursor of the Streptomyces R61 Dd-Peptidase Containing a C-Terminal Extension Is Inactive
Fanuel, Laurence; Granier, Benoît; Wilkin, Jean-Marc et al

in FEBS Letters (1994), 351(1), 49-52

The Streptomyces R61 DD-peptidase gene encodes a 26-residue C-terminal extension which is not found in the mature protein. When the gene was expressed in Escherichia coli, the extension was not cleaved ... [more ▼]

The Streptomyces R61 DD-peptidase gene encodes a 26-residue C-terminal extension which is not found in the mature protein. When the gene was expressed in Escherichia coli, the extension was not cleaved and the precursor protein was not enzymatically active. It also reacted with penicillins significantly more slowly than the mature protein. The introduction of a 'stop' codon after that corresponding to the C-terminal residue of the mature protein resulted in the production of an active protein in the periplasm of E. coli. [less ▲]

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See detailAnionic polymerization of acrylic monomers. 17. Ligated anionic living polymerization of 2-ethylhexyl acrylate as promoted by polydentate lithium alkoxides
Wang, Jin-Shan; Bayard, Philippe; Jérôme, Robert ULg et al

in Macromolecules (1994), 27(18), 4890-4895

Different initiators combined with a new family of mu/sigma dual ligands, i.e., polydentate alkoxides, were used to initiate the anionic polymerization of 2-ethylhexyl acrylate (2EtHA) at low temperatures ... [more ▼]

Different initiators combined with a new family of mu/sigma dual ligands, i.e., polydentate alkoxides, were used to initiate the anionic polymerization of 2-ethylhexyl acrylate (2EtHA) at low temperatures. It has been found that lithium 2(2-methoxyethoxy) ethoxide (LiOEEM) is the most efficient mu/sigma ligand in promoting a living polymerization of that monomer. Although LiOEEM gives rise to a molecularly well-controlled P2EtHA at -78 degrees C in a 9/1 toluene/THF mixture, i.e., quantitative yield, high initiator efficiency (>90%), and narrow molecular weight distribution (M(w)/M(n) down to 1.05), two-step monomer resumption experiments always lead to a bimodal distribution, suggesting that the LiOEEM-complexed P2EtHA anions are not stable. Nevertheless, a perfectly living 2EtHA anionic polymerization process has been obtained at -100 degrees C, keeping other conditions unchanged. In comparison with other types of ligands, such as LiCl and LiOtBu (both mu-ligands) and DB18CE6 and K222 (both sigma-ligands), it has been further demonstrated that the formation of a stable and bulky active complex is at the origin of the anionic living polymerization of 2EtHA, in agreement with our findings in the case of anionic statistical copolymerization of methacrylate and acrylate. [less ▲]

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See detailAnionic polymerization of acrylic monomers. 18. NMR characterization of a unique complex between lithium 2-(2-methoxyethoxy) ethoxide and methyl α-lithioisobutyrate
Wang, Jin-Shan; Jérôme, Robert ULg; Teyssié, Philippe

in Macromolecules (1994), 27(18), 4896-4901

A unique ligand-promoted-loose mixed complex MIB-(Li-3(OEEM)(2))(+) has been characterized for the first time by means of NMR spectroscopy in solution. This new complex, which is a dual mu/sigma one, is ... [more ▼]

A unique ligand-promoted-loose mixed complex MIB-(Li-3(OEEM)(2))(+) has been characterized for the first time by means of NMR spectroscopy in solution. This new complex, which is a dual mu/sigma one, is obviously different from either a simple tight mu-mixed complex, such as nMIBLi.mX (X = Cl or OtBu), or a sigma-cation-binding one with mole charge separation, such as K211/MIBLi. It originates from a simultaneous dual complexation (mu/sigma) of MIBLi by both the lithium alkoxide (mu-mixed complexation) and the chelating polyether components (sigma-cation-binding complexation) of LiOEEM. Furthermore, it has been demonstrated; that, whichever the solvent, i.e., toluene, a 9/1 toluene/THF mixture, or THF, complexation of MIBLi by greater than or equal to 2 mol equiv of LiOEEM produces the same type of complex, i.e., MIB-(Li-3(OEEM)(2))(+), suggesting that, in this strong complex, the lithium cations are strongly coordinated by the ligand. [less ▲]

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See detailAnionic polymerization of acrylic monomers. 19. Effect of various types of ligands other than lithium chloride on the stereochemisty of anionic polymerization of methyl methacrylate
Wang, Jin-Shan; Jérôme, Robert ULg; Teyssié, Philippe

in Macromolecules (1994), 27(18), 4902-4907

The effect of several types of ligands, i.e., 12-CE4 (1), K211 (2), LiOtBu (3), and LiOEEM (4), on the stereochemistry of MMA anionic polymerization at -78 degrees C in various solvents, i.e., toluene ... [more ▼]

The effect of several types of ligands, i.e., 12-CE4 (1), K211 (2), LiOtBu (3), and LiOEEM (4), on the stereochemistry of MMA anionic polymerization at -78 degrees C in various solvents, i.e., toluene, THF, and a 9/1 toluene/THF mixture, has been studied. Similar to the LiCl-complexed system, the stereoregularity of MMA polymerization in the presence of these additives is seemingly controlled by association/complexation equilibria among associated, nonassociated, and ligand-complexed active species. Accordingly, complexation of active species by sigma-chelating ligands such as 12-CE4 and K211 simply shifts the association equilibrium toward the formation of ligand-complexed (nonassociated) species, giving preferably syndiotactic placements (rr) in a 9/1 toluene/THF mixture as well as in toluene. However, the effect of a mu-type ligand, i.e., LiOtBu, seems more complicated. In THF and toluene, similar to ligand-free systems, highly syndiotactic and isotactic PMMAs are produced, respectively, implying the existence of different types of stereoselective LiOtBu-complexed species. In a 9/1 toluene/THF mixture, moreover, addition of LiOtBu gives rise to an increase in isotactic placements (mm) and matches the values observed in toluene. This is in striking contrast to the LiCl-added system, for which it has been tentatively proposed that a meso or raceme placement might also critically depend on the aggregation degree of the living chain in the complexed species. Nevertheless, a mu/sigma dual ligand, i.e., LiOEEM, gives rise to an almost identical stereoregularity (i.e., highly syndiotactic) whatever the solvent used, well consistent with the involvement of the same type of active complex. [less ▲]

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See detailAnionic polymerization of acrylic monomers. 21. Anionic sequential polymerization of 2-ethylhexyl acrylate and methyl methacrylate
Wang, Jin-Shan; Jérôme, Robert ULg; Bayard, Philippe et al

in Macromolecules (1994), 27(18), 4908-4913

A mixed complex of a polydentate lithium alkoxide, i.e., lithium 2-(2-methoxyethoxy) ethoxide (LiOEEM), and of a mono- or bisfunctional organolithium initiator, i.e., (diphenylmethyl)lithium (DPMLi) or ... [more ▼]

A mixed complex of a polydentate lithium alkoxide, i.e., lithium 2-(2-methoxyethoxy) ethoxide (LiOEEM), and of a mono- or bisfunctional organolithium initiator, i.e., (diphenylmethyl)lithium (DPMLi) or lithium naphthalene/diphenylethylene, has been used to synthesize well-controlled AB (BA), ABA, and BAB block copolymers of methylmethacrylate (MMA) (A) and 2-ethylhexyl acrylate (2EtHA) (B), irrespective of the monomer addition order. Although the 2EtHA block copolymerization initiated with monofunctional living PMMA macroanions at -78 degrees C in a 75/25 toluene/THF mixture gives rise to a precisely-tailored PMMA-b-P2EtHA diblock polymer, the reverse sequence, i.e.,from P2EtHA anions to the MMA type monomer, always results in contamination by homo-P2EtHA. This has been interpreted in terms of the short shelf lifetime of P2EtHA anions present. Nevertheless, a pure P2EtHA-b-PMMA type diblock copolymer can be produced at -100 degrees C, while keeping other conditions unchanged. More importantly, a well-controlled PMMA-b-P2EtHA-b-PMMA triblock copolymer has been prepared through a three-stage process with a monofunctional initiator, actually providing a potential pathway toward the direct synthesis of a novel type of fully acrylic thermoplastic elastomer, instead of the more complicated hydrolysis/transalcoholysis process previously demonstrated by us. [less ▲]

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See detailHuman xeroderman group G gene encodes a DNA endonuclease
Habraken, Yvette ULg; Sung, Patrick; Prakash, Louise et al

in Nucleic Acids Research (1994), 22(16), 3312-6

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See detailIncrease of carbonyl fluoride (COF2) in the stratosphere and its contribution to the 1992 budget of inorganic fluorine in the upper stratosphere
Zander, Rodolphe ULg; Rinsland, Curtis P.; Mahieu, Emmanuel ULg et al

in Journal of Geophysical Research (1994), 99(D8), 16737-16743

Volume mixing ratio profiles of COF2 have been derived through most of the stratosphere between 30°N and 54°S from series of 0.01-cm−1 resolution infrared solar spectra recorded in the occultation mode by ... [more ▼]

Volume mixing ratio profiles of COF2 have been derived through most of the stratosphere between 30°N and 54°S from series of 0.01-cm−1 resolution infrared solar spectra recorded in the occultation mode by the atmospheric trace molecule spectroscopy (ATMOS) instrument during the ATLAS 1 space shuttle mission of March–April 1992. When compared with similar results obtained from the ATMOS/Spacelab 3 mission of April–May 1985, the cumulative increase in the burden of COF2 in the middle and upper stratosphere was found to be 67% for that 7-year time interval. By combining a subset of these COF2 results with upper stratospheric concentrations of HF also derived from the ATMOS observations, it was further found that the budget of inorganic fluorine above 35 km altitude increased by (60 ± 10) % over the 1985–1992 time interval, which corresponds to an average exponential rate of increase of (6.7 ± 1.1) % yr−1, or a linear rate of increase referenced to 1985 of (8.5 ± 1.3) % yr−1 at the 1σ confidence level. The total inorganic F atom volume mixing ratio found in the upper stratosphere for 1985 and 1992 and the increase during this period mirror the rise in man-made fluorine-bearing compounds at the ground during the early to mid 1980s. This demonstrates the negligible impact of natural sources of fluorine, in particular volcanic activity, on the observed change of F in the upper stratosphere. Implications of the present findings and comparison with model results are discussed. [less ▲]

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See detailSECULAR TREND AND SEASONAL VARIABILITY OF THE COLUMN ABUNDANCE OF N2O ABOVE THE JUNGFRAUJOCH STATION DETERMINED FROM IR SOLAR SPECTRA
Zander, Rodolphe ULg; EHHALT, D. H.; RINSLAND, Curtis P. et al

in Journal of Geophysical Research (1994), 99(D8), 16745-16756

Infrared solar spectra recorded at the International Scientific Station of the Jungfraujoch (3580 m altitude), Switzerland, in 1950-1951 and from 1984 to 1992 have been analyzed to determine vertical ... [more ▼]

Infrared solar spectra recorded at the International Scientific Station of the Jungfraujoch (3580 m altitude), Switzerland, in 1950-1951 and from 1984 to 1992 have been analyzed to determine vertical column abundances of nitrous oxide (N2O) above the station. The best fit to the relatively dense set of measurements made between 1984 and 1992 indicates a mean exponential rate of increase equal to 0.36 +/- 0.06% yr-1 (1 sigma) and a seasonal modulation of 7.2% peak to peak, the minimum occurring at the end of the winter and the maximum in early September. The column abundances for April of the years 1951, 1984, and 1992 were found equal to 3.49 x 10(18), 3.76 x 10(18), and 3.87 x 10(18) molecules cm-2, respectively; they translate into N2O concentrations at the altitude of the Jungfraujoch equal to 275, 296, and 305 parts per billion by volume. These results indicate that the exponential rate of increase for 1951-1984 was equal to 0.23 +/- 0.04% yr-1 (1 sigma), thus substantially lower than for the 1984-1992 time interval and that the so-called preindustrial levels of N2O pertained until 1951 with most of the increase in atmospheric N2O occurring thereafter. [less ▲]

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See detailSite-directed mutagenesis of penicillin-binding protein 3 of Escherichia coli: role of Val-545
Ayala, Juan; Goffin, Colette; Nguyen-Distèche, Martine ULg et al

in FEMS Microbiology Letters (1994), 121(2), 251-256

Val545 of the Escherichia coli penicillin-binding protein 3 is essential to the acyl transfer mechanism through which the active-site serine 307 is acylated by benzylpenicillin and cephalexin and to the ... [more ▼]

Val545 of the Escherichia coli penicillin-binding protein 3 is essential to the acyl transfer mechanism through which the active-site serine 307 is acylated by benzylpenicillin and cephalexin and to the mechanism through which the protein allows rapidly growing cells to divide. [less ▲]

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See detailAuroral Lyman alpha and H2 bands from the giant planets: 1. Excitation by proton precipitation in the Jovian atmosphere
Rego, Daniel; Prange, Renee; Gérard, Jean-Claude ULg

in Journal of Geophysical Research (1994), 99

This paper is part of a work aimed at modeling the ratio of the observed Jovian auroral intensity at H Lyman-alpha and in the H2 Lyman and Werner bands and interpreting them as diagnostic of the incident ... [more ▼]

This paper is part of a work aimed at modeling the ratio of the observed Jovian auroral intensity at H Lyman-alpha and in the H2 Lyman and Werner bands and interpreting them as diagnostic of the incident magnetospheric particle species and energy. The work is planned in three steps: (1) modeling of the volume excitation rate, (2) modeling of the radiative transfer at Lyman-alpha, (3) application to existing observational data and new data obtained from the Hubble Space Telescope. The present paper deals with the first step. Models of the volume excitation rate have previously been developed for low energy electrons and oxygen ions. However, the energy range of the study has to be extended towards higher energy in view of recent results on the penetration depth of the primary particles. Protons have not been modeled so far. We have used an existing electron code of degradation of energy (Gerard and Singh, 1982) which has been improved, updated and adapted to the case of precipitating protons. The issues of nonequilibrium beam H/H(+) fractions and of getting reliable cross sections over a wide energy range have been considered with particular care. The altitude distribution of the volume excitation rate is compared for electrons and protons, for various initial energies in the range 10-50 keV and 50 keV to 1 MeV, respectively. [less ▲]

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See detailTraitement médicamenteux chronique de l'asthme
Louis, Renaud ULg; Bury, Thierry ULg; Radermecker, Maurice ULg

in Revue Médicale de Liège (1994), 49(8), 429-30

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See detailThe 6-Kilobase C-Erbb2 Promoter Contains Positive and Negative Regulatory Elements Functional in Human Mammary Cell Lines
Grooteclaes, Madeleine; Pasleau, Françoise ULg; Dijkmans, Huguette et al

in Cancer Research (1994), 54(15), 4193-9

A 6-kilobase fragment extending at the 5'-end of the c-erbB2 protooncogene was isolated from a normal human lymphocyte genomic DNA library. The full-length fragment and five subfragments with identical 3 ... [more ▼]

A 6-kilobase fragment extending at the 5'-end of the c-erbB2 protooncogene was isolated from a normal human lymphocyte genomic DNA library. The full-length fragment and five subfragments with identical 3'-ends were obtained by progressive unidirectional deletion from the 5'-end and were cloned in front of the luciferase reporter gene. The hybrid genes were analyzed for transcriptional activity in human mammary cell lines synthesizing low (HBL-100 and T-47D), moderate (MDA-MB-453), or high (BT-474) amounts of the c-erbB2 mRNA and were also analyzed in HeLa cells. Gene-specific expression was observed, indicating the presence of multiple cis-acting sequences in the c-erbB2 promoter. A major negative element is located in the -2- to -4-kilobase region. It is flanked on both sides by positive elements that display enhanced transcriptional activity in the BT-474 tumor cells only. While predominant in the low-expressing cells, the effect of the repressor appears to be overcome by the distal transactivator in the high-expressing BT-474 cells, resulting in a 15 to 50 times increase in luciferase activity relative to the HBL-100 and T-47D cells, respectively. Cell-specific expression relies on the trans-acting factors present in the different cell lines. The formation of cell-specific protein-DNA complexes was demonstrated by gel retardation assay. [less ▲]

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See detailAnionic polymerization of acrylic monomers. 15. Living anionic copolymerization of mixtures of methyl metacrylate and tert-butyl acrylate as promoted by dibenzo-18-crown-6
Wang, Jin-Shan; Jérôme, Robert ULg; Bayard, Philippe et al

in Macromolecules (1994), 27(16), 4615-4620

Although mu-coordinating ligands such as LiCl are effective in promoting the well-controlled living anionic block copolymerization of methyl methacrylate (MMA) and tert-butyl acrylate (tBuA), whichever ... [more ▼]

Although mu-coordinating ligands such as LiCl are effective in promoting the well-controlled living anionic block copolymerization of methyl methacrylate (MMA) and tert-butyl acrylate (tBuA), whichever monomer is first polymerized, it has been previously shown that a copolymerization of mixtures of these two monomers does not proceed as expected, giving poor results in terms of both conversion and molecular weight distribution: that was accounted for by the easy back-biting nucleophilic attack of a highly sensitive methyl ester group by a moderately hindered PtBuA anion. It is now reported that such a situation can be completely modified, when a cation-binding sigma-ligand, i.e., dibenzo-18-CE-6, is used in chelating a sodium counterion and surrounding it with a steric barrier, blocking a large enough space area around the ion pair. In fact, a living copolymerization process of mixtures of MMA and tBuA prevails in THF at -78-degrees-C, in the presence of that Na+/DB-18-CE-6 system. The living copolymer is found, although in a relatively small extent, to be of a statistical type rather than a blocky one or a mixture of two corresponding homopolymers. Furthermore, using the extended Kelen-Tudos method, the monomer reactivity ratios are determined to be r(MMA) = 0.02 and r(tBuA) = 8.81. [less ▲]

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See detailComment je traite un hypertendu avec néphropathie diabétique
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (1994), 49(8), 427-428

1. La néphropathie diabétique, complication tardive du diabète, se caractérise par une protéinurie supérieure à 300 mg/24 heures. Elle n'affecte cependant pas tous les diabétiques. 2. Lorsqu'elle apparaît ... [more ▼]

1. La néphropathie diabétique, complication tardive du diabète, se caractérise par une protéinurie supérieure à 300 mg/24 heures. Elle n'affecte cependant pas tous les diabétiques. 2. Lorsqu'elle apparaît, l'hypertension est fréquente, cette dernière aggravant l'involutivité de l'atteinte rénale. 3. Un contrôle tensionnel optimal ralentit son évolution. 4. Les inhibiteurs de l'enzyme de conversion utilisés tôt, notamment au stade de la microalbuminurie sans hypertension artérielle, possèdent, à côté de leur action antihypertensive, des propriétés antiprolifératives et antiprotéinuriques freinant la dégradation fonctionnelle rénale. 5. Les antagonistes calciques, surtout autres que les dérivés dihydropyridine, peuvent constituer une alternative en cas de contreindication à l'utilisation des inhibiteurs de l'enzyme de conversion. 6. A un stade avancé, le contrôle tensionnel, quelle qu'en soit la manière, joue le rôle protecteur principal sur les reins. [less ▲]

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See detailLa déficience en hormone de croissance chez l'adulte et son traitement
Moreau, L.; Beckers, Albert ULg

in Médecine et Hygiène (1994), 52(2036), 1660-4

Les adultes déficients en hormone de croissance (GH) décèdent prématurément, principalement à cause de la fréquence élevée des affections cardiovasculaires. Depuis que la GH est produite par les ... [more ▼]

Les adultes déficients en hormone de croissance (GH) décèdent prématurément, principalement à cause de la fréquence élevée des affections cardiovasculaires. Depuis que la GH est produite par les techniques de biologie moléculaire, il est possible de proposer un traitement substitutif. Ce traitement améliore le bilan lipidique, entraîne une redistribution de la graisse d'androïde en gynoïde, une réduction de la masse graisseuse, une augmentation de la masse des tissus maigres et du volume de l'eau extracellulaire. Le poids des patients est légèrement réduit par le traitement substitutif. La masse de muscle strié squelettique est augmentée, ainsi que le contenu osseux (BMC) et la densité osseuse (BMD). La fonction cardiaque et la qualité de vie sont améliorées. [less ▲]

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See detailIdentification of Clostridium tyrobutyricum and related species using sugar fermentation, organic acid formation and DNA probes based on 16S rRNA sequences
Klijn, N.; Bovie, C.; Dommes, Jacques ULg et al

in Systematic and Applied Microbiology (1994), 17(2), 249-256

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See detailLacunarity, fractal, and magnetic transition behaviors in a generalized Eden growth-process
Vandewalle, Nicolas ULg; Ausloos, Marcel ULg

in Physical Review. E : Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics (1994), 50(2), 635-638

The effect of an internal extra degree of freedom introduced into the simplest growth model (the Eden model) leads to a joint physical and geometrical transition. Lacunarity, fractal, and magnetic ... [more ▼]

The effect of an internal extra degree of freedom introduced into the simplest growth model (the Eden model) leads to a joint physical and geometrical transition. Lacunarity, fractal, and magnetic transitions are indeed reported to be at the same critical values of the growth parameters. A logarithmic behavior of the cluster mass on this critical value was found. [less ▲]

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See detailImprovement of Gc-Rich Template Amplification by Inverse Pcr
Moreau, Alain; Duez, Colette ULg; Dusart, Jean

in BioTechniques (1994), 17(2), 232-4

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See detailEffect of topographic stress on circulation in the Western Mediterranean
Alvarez, A.; Tintore, J.; Holloway, G. et al

in Journal of Geophysical Research (1994), 99(C8), 16053-16064

The interaction of eddies with seafloor topography can exert large systematic forces on ocean circulation. Using a statistical mechanics approach it is possible to obtain a parametrization of this effect ... [more ▼]

The interaction of eddies with seafloor topography can exert large systematic forces on ocean circulation. Using a statistical mechanics approach it is possible to obtain a parametrization of this effect (the Neptune effect) for application in large-scale ocean circulation models. Circulation of the western Mediterranean has been observed to follow a definite cyclonic path. Numerical models usually show good qualitative agreement for the large-scale circulation but show systematic deficiencies at a subbasin scale. We have tested the importance of the Neptune effect on the circulation of the western Mediterranean Sea. To perform this test, different numerical experiments on western Mediterranean circulation were done with and without eddy-topography interaction. As a first step we analyze the influence of the Neptune effect in an ideal western Mediterranean with closed straits. After these experiments the more realistic case of open straits is studied. All the experiments show that the Neptune effect may be a significant factor in the basin and subbasin scale circulation in the western Mediterranean Sea. [less ▲]

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See detailA 5-Year Controlled Randomized Study of Prevention of Postmenopausal Trabecular Bone Loss with Nasal Salmon Calcitonin and Calcium
Reginster, Jean-Yves ULg; Meurmans, L.; Deroisy, Rita ULg et al

in European Journal of Clinical Investigation (1994), 24(8), 565-9

The aim of this paper was to evaluate the long-term (5 years) efficacy of nasal salmon calcitonin in prevention of trabecular postmenopausal bone loss, which was a follow-up of a previously published ... [more ▼]

The aim of this paper was to evaluate the long-term (5 years) efficacy of nasal salmon calcitonin in prevention of trabecular postmenopausal bone loss, which was a follow-up of a previously published study (3 years); a randomized, controlled group comparison. One hundred healthy postmenopausal women were randomly chosen from those (186) having completed the 3 year protocol. The 100 women were allocated to an additional 2 year period (total of 5 years) of treatment with either 500 mg d-1, 5 days week-1 of calcium or the same amount of calcium plus 50 IU d-1, 5 days per week of nasal salmon calcitonin, 87 (87%) women complied with the protocol throughout. The main outcome measures were the bone mineral density of the lumbar spine (1-BMD) (DPA) and biochemical parameters reflecting bone turnover (serum alkaline phosphatases, urinary calcium/creatinine and hydroxyproline/creatinine ratios). The women receiving calcium alone presented a significant decrease in 1-BMD after 6 months [-1.6 (0.5)%] [mean(SEM)] (P < 0.01) and this decrease remained significant after 36 months [-6.1(0.8)%] (P < 0.01) and until the end of the trial [-6.6(1.0)% at t60] (P < 0.01). In women receiving calcium and calcitonin, 1-BMD significantly increased after 36 months [+2(0.7%] (P < 0.01) and 42 months [+2.5(0.7)%] (P < 0.01 and was unchanged at the other times of investigation [+1.1 (1.1)% at t60] (NS). The evolution of BMD in the two groups was highly significantly different (P < 0.001) since the sixth month of the study and remained so until the end of the study.(ABSTRACT TRUNCATED AT 250 WORDS) [less ▲]

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See detailSelenium deficiency triggering intractable seizures
RAMAEKERS, Vincent ULg; Calomme, M.; Vanden Berghe, D. et al

in Neuropediatrics (1994), 25(4), 217-23

Two children with severe neurodevelopmental retardation and elevated liver function tests developed intractable seizures during the first year of life. Detectable neurometabolic conditions have been ruled ... [more ▼]

Two children with severe neurodevelopmental retardation and elevated liver function tests developed intractable seizures during the first year of life. Detectable neurometabolic conditions have been ruled out. At the time of seizures evidence for systemic selenium deficiency could be documented. The youngest patient, who manifested intractable fits from the fourth day of life, died at the age of ten months. Neuropathologic examination was consistent with Progressive Neuronal Degeneration of Childhood (PNDC) with liver disease or formerly known as Alpers disease. In the oldest child, whose diet was normally balanced, fits started from the age of 11 months and features of long-standing selenium deficiency became apparent from the age of 1 1/2 years and consisted of liver function disturbances, depigmented hair and osteoarthropathy. Oral substitution with selenium supplements in both children (3-5 micrograms/kg body weight) resulted in reduction of seizures and improvement of the EEG recordings after two weeks while liver function became normal. Two of the seleno-dependent enzymes Glutathione Peroxidase (GPX) and Phospholipid Hydroperoxide Glutathione Peroxidase (PHGPX) are speculated to play a key-role in the defence of neuronal cells against oxygen radical formation and peroxidative processes. Our findings support the hypothesis that the presence of selenium depletion in the brain amongst patients with epilepsy constitutes an important triggering factor for the origin of intractable seizures and subsequent neuronal damage. [less ▲]

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See detailAcute Polymyopathy after Carbamate Poisoning in a Dog
Mc Entee, Kathleen ULg; Poncelet, Luc; Clercx, Cécile ULg et al

in Veterinary Record : Journal of the British Veterinary Association (1994), 135(4), 88-90

The acute polymyopathy in a seven-year-old German shepherd dog was attributed to the muscular hypertonia, tremors and seizures which developed during the acute phase of carbamate poisoning. After two days ... [more ▼]

The acute polymyopathy in a seven-year-old German shepherd dog was attributed to the muscular hypertonia, tremors and seizures which developed during the acute phase of carbamate poisoning. After two days of generalised muscular rigidity, the dog adopted a characteristic fetal position which could be explained by the imbalance between the injuries to the extensor and flexor muscles. The polymyopathy resolved gradually over the course of a week. [less ▲]

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See detailMacromolecular engineering of polylactones and polylactides. 18. Synthesis of star-branched aliphatic polyesters bearing various functinal end groups
Tian, Dong; Dubois, Philippe; Jérôme, Robert ULg et al

in Macromolecules (1994), 27(15), 4134-4144

Three-arm star-branched aliphatic polyesters have been synthesized by an appropriate termination reaction of the living chains prepared by ring-opening polymerization with aluminum alkoxides. The use of ... [more ▼]

Three-arm star-branched aliphatic polyesters have been synthesized by an appropriate termination reaction of the living chains prepared by ring-opening polymerization with aluminum alkoxides. The use of functional aluminum alkoxides, Et2AlOCH2X with X = CH2CH2CH=CH2 and (CH2)10Br, has led to X functional end-capped star-branched polyesters. Trimesic acid trichloride has proved to be an efficient termination agent for the living poly(epsilon-caprolactone) [PCL] chains ended with a reactive aluminum alkoxide group. A quantitative end functionalization has been reported for bromide and 1-pentene end-capped star-branched PCL. The bromide end groups have been converted into azido end groups, which have been subsequently reduced to the expected primary amine end-capped star-branched PCL by catalytic transfer hydrogenation in DMF. In contrast to living PCL, reaction of trimesic acid chloride with the aluminum alkoxide end group of living poly(L,L)lactide [P(L,L)LA] and living poly(epsilon-caprolactone-b-(L,L)lactide) [P(CL-b-(L,L)LA] chains has produced star-branched polyesters within a very poor yield. This result is more likely due to a steric effect of the methyl group in a-position of the terminal aluminum alkoxide. This drawback has been overcome to some extent by initiating the living polymerization of (L,L)LA with primary amine end-capped star-branched PCL in the presence of triethylaluminum. Formation of a hydroxyl end-capped star-branched poly(epsilon-caprolactone-b-(L,L)lactide) diblock copolymer has accordingly been reported. [less ▲]

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See detailInvestigation of the surface activity of a poly(styrene-b-dimethylsiloxane) copolymer blended within a polystyrene matrix
Petitjean, Serge; Ghitti, G.; Jérôme, Robert ULg et al

in Macromolecules (1994), 27

The surface properties of thin polystyrene films are deeply modified by the addition of various amounts of a poly(styrene-b-dimethylsiloxane) copolymer-or poly(S-b-DMS)-as confirmed by a series of ... [more ▼]

The surface properties of thin polystyrene films are deeply modified by the addition of various amounts of a poly(styrene-b-dimethylsiloxane) copolymer-or poly(S-b-DMS)-as confirmed by a series of analytical methods. In addition to the surface tension which has been estimated from wettability and contact angle measurements, surface composition has been analyzed by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectrometry (SIMS). Surface studies have been completed by the analysis of the depth distribution of siloxane from the surface by XPS and SIMS. Finally, the surface activity of poly(S-b-DMS) has been investigated in solution. Indeed, changes in the surface tension of polystyrene solutions in THF have been measured in relation to the addition of the diblock copolymer. All the experimental data agree with the complete coverage of the polystyrene films with the poly(S-b-DMS) copolymer. This situation already prevails in the solutions prepared as precursors to the thin polystyrene films. Accordingly, surface characteristics of film freshly prepared by solvent-casting are unaffected by subsequent annealing. [less ▲]

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