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See detailFolding of class A beta-lactamases is rate-limited by peptide bond isomerization and occurs via parallel pathways.
Vandenameele, Julie ULg; Lejeune, Annabelle ULg; Di Paolo, Alexandre ULg et al

in Biochemistry (2010), 49(19), 4264-75

Class A beta-lactamases (M(r) approximately 29000) provide good models for studying the folding mechanism of large monomeric proteins. In particular, the highly conserved cis peptide bond between residues ... [more ▼]

Class A beta-lactamases (M(r) approximately 29000) provide good models for studying the folding mechanism of large monomeric proteins. In particular, the highly conserved cis peptide bond between residues 166 and 167 at the active site of these enzymes controls important steps in their refolding reaction. In this work, we analyzed how conformational folding, reactivation, and cis/trans peptide bond isomerizations are interrelated in the folding kinetics of beta-lactamases that differ in the nature of the cis peptide bond, which involves a Pro167 in the BS3 and TEM-1 enzyme, a Leu167 in the NMCA enzyme, and which is missing in the PER-1 enzyme. The analysis of folding by spectroscopic probes and by the regain of enzymatic activity in combination with double-mixing procedures indicates that conformational folding can proceed when the 166-167 bond is still in the incorrect trans form. The very slow trans --> cis isomerization of the Glu166-Xaa167 peptide bond, however, controls the final step of folding and is required for the regain of the enzymatic activity. This very slow phase is absent in the refolding of PER-1, in which the Glu166-Ala167 peptide bond is trans. The double-mixing experiments revealed that a second slow kinetic phase is caused by the cis/trans isomerization of prolines that are trans in the folded proteins. The folding of beta-lactamases is best described by a model that involves parallel pathways. It highlights the role of peptide bond cis/trans isomerization as a kinetic determinant of folding. [less ▲]

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See detailThe Folding Process of Hen Lysozyme: A Perspective from the 'New View'
Matagne, André ULg; Dobson, Christopher M.

in Cellular and Molecular Life Sciences : CMLS (1998), 54(4), 363-71

How a conformationally disordered polypeptide chain rapidly and efficiently achieves its well-defined native structure is still a major question in modern structural biology. Although much progress has ... [more ▼]

How a conformationally disordered polypeptide chain rapidly and efficiently achieves its well-defined native structure is still a major question in modern structural biology. Although much progress has been made towards rationalizing the principles of protein structure and dynamics, the mechanism of the folding process and the determinants of the final fold are not yet known in any detail. One protein for which folding has been studied in great detail by a combination of diverse techniques is hen lysozyme. In this article we review the present state of our knowledge of the folding process of this enzyme and focus in particular on recent experiments to probe some of its specific features. These results are then discussed in the context of the 'new view' of protein folding based on energy surfaces and landscapes. It is shown that a schematic energy surface for lysozyme folding, which is broadly consistent with our experimental data, begins to provide a unified model for protein folding through which experimental and theoretical ideas can be brought together. [less ▲]

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See detailFolie et divinité dans le monde gréco-romain
Macedo, Gabriel ULg

Article for general public (2012)

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See detail"La folie heureuse" : à propos d'un passage d'Horace (Épîtres II, 2, v. 128-140)
Ricciardetto, Antonio ULg

in Filiber, Carine (Ed.) Vertiges de la folie. Catalogue de l'exposition (Musée de la Vie Wallonne, Liège, 30/03-19/08/2012) (2012)

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See detailLa Folie Mallarmé
Durand, Pascal ULg

in Courrier du Centre International d'Etudes Poétiques (2000), 225

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See detailFoliicolous lichens from Southeastern United States
Sérusiaux, Emmanuël ULg

in Bryologist (1979), 82

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See detailFoliicolous lichens from Zimbabwe
Sérusiaux, Emmanuël ULg

in Lichenologist (1983), 15

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See detailFoliicolous lichens: ecological and chorological data
Sérusiaux, Emmanuël ULg

in Botanical Journal of the Linnean Society (1986), 100

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See detailFolinic acid treatment for schizophrenia associated with folate receptor autoantibodies.
RAMAEKERS, Vincent ULg; Thony, B.; Sequeira, J. M. et al

in Molecular genetics and metabolism (2014), 113(4), 307-14

BACKGROUND: Auto-antibodies against folate receptor alpha (FRalpha) at the choroid plexus that block N(5)-methyltetrahydrofolate (MTHF) transfer to the brain were identified in catatonic schizophrenia ... [more ▼]

BACKGROUND: Auto-antibodies against folate receptor alpha (FRalpha) at the choroid plexus that block N(5)-methyltetrahydrofolate (MTHF) transfer to the brain were identified in catatonic schizophrenia. Acoustic hallucinations disappeared following folinic acid treatment. Folate transport to the CNS prevents homocysteine accumulation and delivers one-carbon units for methyl-transfer reactions and synthesis of purines. The guanosine derivative tetrahydrobiopterin acts as common co-factor for the enzymes producing dopamine, serotonin and nitric oxide. METHODS: Our study selected patients with schizophrenia unresponsive to conventional treatment. Serum from these patients with normal plasma homocysteine, folate and vitamin B12 was tested for FR autoantibodies of the blocking type on serial samples each week. Spinal fluid was analyzed for MTHF and the metabolites of pterins, dopamine and serotonin. The clinical response to folinic acid treatment was evaluated. RESULTS: Fifteen of 18 patients (83.3%) had positive serum FR auto-antibodies compared to only 1 in 30 controls (3.3%) (chi(2)=21.6; p<0.0001). FRalpha antibody titers in patients fluctuated over time varying between negative and high titers, modulating folate flux to the CNS, which explained low CSF folate values in 6 and normal values in 7 patients. The mean+/-SD for CSF MTHF was diminished compared to previously established controls (t-test: 3.90; p=0.0002). A positive linear correlation existed between CSF MTHF and biopterin levels. CSF dopamine and serotonin metabolites were low or in the lower normal range. Administration of folinic acid (0.3-1mg/kg/day) to 7 participating patients during at least six months resulted in clinical improvement. CONCLUSION: Assessment of FR auto-antibodies in serum is recommended for schizophrenic patients. Clinical negative or positive symptoms are speculated to be influenced by the level and evolution of FRalpha antibody titers which determine folate flux to the brain with up- or down-regulation of brain folate intermediates linked to metabolic processes affecting homocysteine levels, synthesis of tetrahydrobiopterin and neurotransmitters. Folinic acid intervention appears to stabilize the disease process. [less ▲]

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See detailFolipidine, a new type quinoline alkaloid from plants of the Haplophyllum genus
Akhmedzhanova, V. I.; Rasulova, K. A.; Bessonova, I. A. et al

in Chemistry of Natural Compounds (2005), 41(1, JAN-FEB), 60-64

The new quinoline alkaloid folipidine, the structure of which was established by chemical transformations and spectral data (UV, IR, mass, NMR) using APT 2D H-1-H-1 COSY, NOESY, and H-1-(13)CHSQC, HMBC ... [more ▼]

The new quinoline alkaloid folipidine, the structure of which was established by chemical transformations and spectral data (UV, IR, mass, NMR) using APT 2D H-1-H-1 COSY, NOESY, and H-1-(13)CHSQC, HMBC, was isolated from two plants of the Haplophyllum mints. Folipidine is the first representative of a new type of quinoline alkaloids that contain a heteroaromatic skeleton of [3,4-b]conjugated pyrrole and quinoline fragments. The total alkaloids of these plants exhibit antitumor activity. Folipidine does not possess such activity. [less ▲]

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See detailLe folk-lore [sic] et les sociétés historiques
Kurth, Godefroid ULg

in Kurth, Godefroid (Ed.) Le folk-lore [sic] et les sociétés historiques (1888)

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See detailFollicle Stimulating Hormone -Secreting Pituitary adenomas
Beckers, Albert ULg; Stevenaert, Achille ULg; Mashiter, K. et al

in Journal of Clinical Endocrinology and Metabolism (1985), 61(3), 525-528

This retrospective study concerns 40 patients with an apparently nonsecretory pituitary adenoma who were operated on during an 11-yr period from 1971 to 1981. Among them, 6 men had elevated serum FSH ... [more ▼]

This retrospective study concerns 40 patients with an apparently nonsecretory pituitary adenoma who were operated on during an 11-yr period from 1971 to 1981. Among them, 6 men had elevated serum FSH levels. LH levels were normal in 5 and slightly elevated in 1. Testosterone levels were low in 2 patients and within normal limits in 2 others. Sexual impotency had developed from 6 months to 1 yr before surgery in all patients. Primary hypogonadism could be eliminated on clinical grounds (recent onset of hypogonadism, previous fertility of 5 of the 6, and postoperative improvement). After transsphenoidal adenomectomy, FSH levels returned to normal values in all, and clinical recovery occurred in most patients. Tumor tissue obtained at operation stained positively for the gonadotropins, but was negative for other pituitary hormones in all patients. The most probable explanation for these findings was that the tumors were responsible for the elevated FSH secretion. This explanation is supported by the immunocytochemical identification of gonadotropin-containing cells in the tumors. We conclude that these 6 men frm a series of 40 patients who presented with pituitary tumor but no GH, PRL, or ACTH hypersecretion had primary gonadotropinomas. [less ▲]

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See detailA follicle-stimulating-hormone secreting pituitary adenoma treated with long acting repeatable bromocriptine.
Abs, R.; Beckers, Albert ULg; De Longueville, M.

in Journal of Endocrinological Investigation (1990), 13

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See detailFollicular dendritic cells act as accessory cells
Heinen, Ernst ULg; Cormann, N.; Lesage, F. et al

in Progress in Leukocyte Biology (1988), 7

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See detailFollicular dendritic cells control engulfment of apoptotic bodies by secreting Mfge8.
Kranich, Jan; Krautler, Nike Julia; Heinen, Ernst ULg et al

in Journal of Experimental Medicine (2008), 205(6), 1293-302

The secreted phosphatidylserine-binding protein milk fat globule epidermal growth factor 8 (Mfge8) mediates engulfment of apoptotic germinal center B cells by tingible-body macrophages (TBMphis ... [more ▼]

The secreted phosphatidylserine-binding protein milk fat globule epidermal growth factor 8 (Mfge8) mediates engulfment of apoptotic germinal center B cells by tingible-body macrophages (TBMphis). Impairment of this process can contribute to autoimmunity. We show that Mfge8 is identical to the mouse follicular dendritic cell (FDC) marker FDC-M1. In bone-marrow chimeras between wild-type and Mfge8(-/-) mice, all splenic Mfge8 was derived from FDCs rather than TBMphis. However, Mfge8(-/-) TBMphis acquired and displayed Mfge8 only when embedded in Mfge8(+/+) stroma, or when situated in lymph nodes draining exogenous recombinant Mfge8. These findings indicate a licensing role for FDCs in TBMphi-mediated removal of excess B cells. Lymphotoxin-deficient mice lacked FDCs and splenic Mfge8, and suffer from autoimmunity similar to Mfge8(-/-) mice. Hence, FDCs facilitate TBMphi-mediated corpse removal, and their malfunction may be involved in autoimmunity. [less ▲]

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See detailFollicular Dendritic Cells Do Not Produce Tnf-Alpha nor its Receptor
Mancini, I.; Bosseloir, A.; Hooghe-Peters, E. et al

in Advances in Experimental Medicine and Biology (1993), 329

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See detailFollicular dendritic cells in lymph nodes after x-irradiation.
Kinet-Denoel, C.; Heinen, Ernst ULg; Radoux, Dominique ULg et al

in International Journal of Radiation Biology and Related Studies in Physics, Chemistry, and Medicine (1982), 42(2), 121-30

Follicular dendritic cells (FDC), non lymphoid cells present in lymph follicles, are characterized by numerous cytoplasmic processes retaining antigen-antibody complexes. Their origin, nature and function ... [more ▼]

Follicular dendritic cells (FDC), non lymphoid cells present in lymph follicles, are characterized by numerous cytoplasmic processes retaining antigen-antibody complexes. Their origin, nature and function are unknown. Mice inguinal lymph nodes after 4.5 or 7.5 Gy X-irradiation were depleted of lymphoid cells. Ultrastructural observations during the first few days post-irradiation show that FDC are unaltered and possess dendritic processes enveloping dense material. Furthermore, they show intense metabolic activity. A lamina densa, never observed so well-developed in other lymph node cells, was detected around the nuclear envelope. The localization of junctions between FDC was analysed. FDC preserve their typical cytoplasmic processes even if lymphoid cells are rare. The latter thus seem not to be responsible for the maintenance of FDC integrity or their development. The possible role of this for antibody production is discussed. Irradiated lymph nodes of lymphoid cells are highly convenient for studying FDC. Isolation of FDC from irradiated lymph organs would seem to be possible. [less ▲]

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See detailThe follicular dendritic cells in normal and pathological conditions
Heinen, Ernst ULg

Book published by Springer (1995)

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