Showing papers by "University of Rouen published in 2000"
TL;DR: Surprisingly, xylose-specific IgE antibodies that bound to Lol p 11 and bromelain did not recognize closely related xylOSE-containing structures on horseradish peroxidase, phytohemeagglutinin, Ole e 1, and Ara h 1.
394 citations
TL;DR: In this paper, the atomic mixing induced by high-energy heavy ion irradiation at the Tb-on-Fe interface was investigated by using the probe layer at the top of iron layers in Tb/Fe multilayers.
Abstract: Deposition of a ${}^{57}\mathrm{Fe}$ probe layer at the top of iron layers in Tb/Fe multilayers has allowed us to study locally the atomic mixing induced by high-energy heavy-ion irradiation at the Tb-on-Fe interface. The structural and magnetic transformations induced by ion irradiation of the probe layer were investigated by ${}^{57}\mathrm{Fe}$ conversion electron M\"ossbauer spectrometry. To study directional effects of the ion beam, we have irradiated a stack of two pieces of the same multilayer set face to face. No change in the average composition of the mixed Tb-on-Fe interface was observed when the incident ion direction is changed from a Tb layer to a Fe layer, or from a Fe layer to a Tb layer.
277 citations
TL;DR: The spinodal decomposition is known to occurr in iron-chromium-based model and industrial alloys during long-term aging at intermediate temperatures, and its evolution quantified by means of various microstructural paramaters directly accessible from concentration profiles.
213 citations
TL;DR: In this paper, the microstructures of electroless plated and thermally aged nanocrystalline nickel were investigated on an atomic scale with a tomographic atom probe (TAP).
188 citations
TL;DR: The first enantiopure N-fluoro quaternary ammonium salts of cinchona alkaloids as enantioselective fluorinating agents are reported and exhibited asymmetric induction up to 61% on fluorination of enolates and silyl enol ethers of 2-methyl-1-tetralone.
153 citations
TL;DR: Whether the anxiogenic effects of caffeine observed in mice depend on the blockade of A2A receptor or their long-term blockade after chronic ingestion of caffeine may be responsible for increase proneness to anxiety.
Abstract: Rationale: The elevated plus-maze and the light/dark box are two established anxiety tests in rodents, which are useful to screen putative anxiogenic effects of drugs. Objective: Caffeine is well known to promote anxious behaviour in humans and animal models, but the precise site of action of the drug is still a matter of debate. The present study investigated whether the anxiogenic effects of caffeine observed in mice depend on the blockade of A2A receptor. First, the effects induced by the non-selective drug caffeine were compared with those elicited by two selective A2A receptor antagonists over a wide range of doses in the same experimental conditions. The effects of A2A or A1 adenosine receptor agonists and of a selective A1 adenosine receptor antagonist were also investigated. Second, wild-type and A2A receptor knockout mice offered another approach to delineate the role played by A2A receptor in caffeine’s anxiogenic effects. Methods: Mice were exposed to the elevated plus-maze or to the light/dark box for 5 min after acute or chronic administration of tested drugs. Results: Caffeine acutely administered (50 or 100 mg/kg IP) induced anxiety-like effects in both procedures. Its chronic administration (50 mg/kg IP twice daily) for 1 week or consumption in the drinking water (0.3 g/l) for 8 days or 2 months were also anxiogenic in the plus-maze test. The A2A receptor antagonists ZM241385 (up to 60 mg/kg IP) and SCH58261 (up to 10 mg/kg IP) were devoid of acute effects in both tests. One week administration of ZM241385 (30 mg/kg IP) or SCH58261 (3 mg/kg IP) had no effects in the plus-maze test. An antagonist (DPCPX) and an agonist (CPA) at A1 receptors had no acute effects on anxiety-related indices, whereas an A2A receptor agonist (CGS 21680) displayed non-specific motor effects in the plus-maze test. Acute administration of caffeine (50 mg/kg IP) induced no clear-cut anxiety-like effects in the plus-maze test in A2A receptor knockout mice that exhibited higher basal anxiety levels than wild-type mice. Chronic administration (50 mg/kg IP twice daily) for 1 week elicited less anxiety-like behaviour in A2A receptor knockout than in wild-type mice. Conclusions: Adaptative mechanisms following mutation in A2A receptors or their long-term blockade after chronic ingestion of caffeine may be responsible for increase proneness to anxiety. However, the short-term anxiety-like effect of caffeine in mice might not be related solely to the blockade of adenosine A2A receptors, since it is not shared by A2A selective antagonists.
146 citations
TL;DR: The wavelet analysis provides an efficient tool in numerous signal-processing problems and has been implemented in optical processing techniques, such as in-line holography, and the technique proposed is implemented and experimental results are presented.
141 citations
TL;DR: In this paper, the dynamics of a high power Yb3+-doped double-clad fiber laser in various optical configurations operating in the 1.08 μm wavelength were investigated.
130 citations
TL;DR: The hypothesis that the respective roles of GHRH and PACAP in the control of GH secretion are totally inverted in phylogenetically distant groups of vertebrates is presented and provides a unique model in which to investigate the structural and functional facets of evolution.
Abstract: Growth hormone-releasing hormone (GHRH) and pituitary adenylate cyclase-activating polypeptide (PACAP) belong to the same superfamily of regulatory neuropeptides and have both been characterized on the basis of their hypophysiotropic activities. This review describes the molecular evolution of the GHRH/PACAP gene family from urochordates to mammals and presents the hypothesis that the respective roles of GHRH and PACAP in the control of GH secretion are totally inverted in phylogenetically distant groups of vertebrates. In mammals, GHRH and PACAP originate from distinct precursors whereas, in all submammalian taxa investigated so far, including birds, amphibians and fish, a single precursor encompasses a GHRH-like peptide and PACAP. In mammals, GHRH-containing neurons are confined to the infundibular and dorsomedial nuclei of the hypothalamus while PACAP-producing neurons are widely distributed in hypothalamic and extrahypothalamic areas. In fish, both GHRH- and PACAP-immunoreactive neurons are restricted to the diencephalon and directly innervate the adenohypophysis. In mammals and birds, GHRH plays a predominant role in the control of GH secretion. In amphibians, both GHRH and PACAP are potent stimulators of GH release. In fish, PACAP strongly activates GH release whereas GHRH has little or no effect on GH secretion. The GHRH/PACAP family of peptides thus provides a unique model in which to investigate the structural and functional facets of evolution.
130 citations
TL;DR: From light-scattering-based radii of gyration and F4-based hydrodynamic radii (Rh) it is found that the ratio Rg/Rh is reasonably consistent with a globular conformation and gives further evidence in favour of the “wattle blossom model” proposed by Connolly et al.
126 citations
TL;DR: A review of the contributions of the atom probe field-ion microscopy (APFIM) technique to the microstructural characterization of pressure vessel steels and to the understanding of the embrittlement of these materials during neutron irradiation is presented in this article.
TL;DR: In this paper, the fractal dimensions derived from laser-induced fluorescence (LIF) of OH and Mie scattering images were determined by analysis of the flame front images using the caliper technique.
TL;DR: The endosperm of hexaploid wheat was shown to contain a high molecular weight starch synthase analogous to the product of the maize du1 gene, starch synthases III (SSIII; DU1).
Abstract: The endosperm of hexaploid wheat (Triticum aestivum [L.]) was shown to contain a high molecular weight starch synthase (SS) analogous to the product of the maize du1 gene, starch synthase III (SSIII; DU1). cDNA and genomic DNA sequences encoding wheat SSIII were isolated and characterized. The wheat SSIII cDNA is 5,346 bp long and contains an open reading frame that encodes a 1,628-amino acid polypeptide. A putative N-terminal transit peptide, a 436-amino acid C-terminal catalytic domain, and a central 470-amino acid SSIII-specific domain containing three regions of repeated amino acid similarity were identified in the wheat gene. A fourth region between the transit peptide and the SSIII-specific domain contains repeat motifs that are variable with respect to motif sequence and repeat number between wheat and maize. In dicots, this N-terminal region does not contain repeat motifs and is truncated. The gene encoding wheat SSIII, designated ss3, consists of 16 exons extending over 10 kb, and is located on wheat chromosome I. Expression of ss3 mRNA in wheat was detected in leaves, pre-anthesis florets, and from very early to middle stage of endosperm development. The entire N-terminal variable repeat region and the majority of the SSIII-specific domain are encoded on a single 2,703-bp exon. A gene encoding a class III SS from the Arabidopsis genome sequencing project shows a strongly conserved exon structure to the wheat ss3 gene, with the exception of the N-terminal region. The evolutionary relationships of the genes encoding monocot and dicot class III SSs are discussed.
TL;DR: Results indicate that calreticulin and perhaps other plant reticuloplasmins are possibly largely excluded from vesicles exported from the ER and probably retained in the ER by mechanisms that rely primarily on signals other than H/KDEL motifs.
Abstract: Using pulse–chase experiments combined with immunoprecipitation and N-glycan structural analysis, we showed that the retrieval mechanism of proteins from post–endoplasmic reticulum (post-ER) compartments is active in plant cells at levels similar to those described previously for animal cells. For instance, recycling from the Golgi apparatus back to the ER is sufficient to block the secretion of as much as 90% of an extracellular protein such as the cell wall invertase fused with an HDEL C-terminal tetrapeptide. Likewise, recycling can sustain fast retrograde transport of Golgi enzymes into the ER in the presence of brefeldin A. However, on the basis of our data, we propose that this retrieval mechanism in plants has little impact on the ER retention of a soluble ER protein such as calreticulin. Indeed, the latter is retained in the ER without any N-glycan–related evidence for a recycling through the Golgi apparatus. Taken together, these results indicate that calreticulin and perhaps other plant reticuloplasmins are possibly largely excluded from vesicles exported from the ER. Instead, they are probably retained in the ER by mechanisms that rely primarily on signals other than H/KDEL motifs.
TL;DR: In this paper, the structure and electronic properties of ferrimagnetic double perovskites were investigated, and it was argued that a direct Re-Re t_2g-Re_ t2g interaction is the main cause for the metallic character of the Ba compound; the smaller size of Ca and the monoclinic distortion (which lifts the degeneracy of {t 2g} states seem to disrupt the ReRe interaction in the case of the Ca compound, making it nonmetallic for the same electron count).
Abstract: We have investigated the structure and electronic properties of ferrimagnetic double perovskites, {A_2FeReO_6} (A = Ca, Sr, Ba). The A = Ba phase is cubic (Fm3m) and metallic, while the A = Ca phase is monoclinic {P2_1 /n} and nonmetallic. Fe{^57 Mossbauer} spectroscopy shows that iron is present mainly in the high spin S = (5/2) {Fe^3+} state in the Ca compound, while it occurs in an intermediate state between high spin {Fe^2+ and Fe^3+} in the Ba compound. It is argued that a direct {Re t_2g-Re_ t2g} interaction is the main cause for the metallic character of the Ba compound; the smaller size of Ca and the monoclinic distortion (which lifts the degeneracy of {t_2g} states seem to disrupt the Re-Re interaction in the case of the Ca compound, making it nonmetallic for the same electron count.
TL;DR: Gliadin nanoparticles show a high capacity of non-specific interaction with the intestine, whereas DBA binding to the surface of these carriers provided a greater specificity for colonic mucosa.
TL;DR: In this article, a field-imaging technique based on high-speed laser tomography measured the temporal evolution of local flame properties, including local curvature and local displacement speed.
TL;DR: The results suggest that fish secrete antibacterial glycoproteins able to kill bacteria by forming large pores in the target membrane, well correlated with a strong antibacterial activity against both gram-negative and gram-positive bacteria.
TL;DR: The results of this study may strengthen the idea that the cerebellar vermis is involved in autism, as already suggested in the guinea pig.
TL;DR: The discrete localization of PACAP binding sites as well as PAC1‐R and VPAC2‐R mRNAs in neuroepithelia during embryonic life and postnatal development strongly suggests that PACAP, acting through PAC1-R and/or VPAC1‐ R, may play a crucial role in the regulation of neurogenesis in the rat brain.
Abstract: The distribution and density of pituitary adenylate cyclase-activating polypeptide (PACAP) binding sites as well as PACAP-specific receptor 1 (PAC1-R), vasoactive intestinal polypeptide/PACAP receptor 1 (VPAC1-R), and VPAC2-R mRNAs have been investigated in the rat brain from embryonic day 14 (E14) to postnatal day 8 (P8). Significant numbers of binding sites for the radioiodinated, 27-amino-acid form of PACAP were detected as early as E14 in the neuroepithelia of the metencephalon and the myelencephalon. From E14 to E21, the density of binding sites in the germinative areas increased by 3- to 5-fold. From birth to P12, the density of binding sites gradually declined in all neuroepithelia except in the external granule cell layer of the cerebellum, where the level of binding sites remained high during the first postnatal weeks. Only low to moderate densities of PACAP binding sites were found in regions other than the germinative areas, with the exception of the internal granule cell layer of the cerebellum, which contained a high density of sites. The localization of PACAP receptor mRNAs was investigated by in situ hybridization using [(35)S] uridine triphosphate-specific riboprobes. The evolution of the distribution of PAC1-R and VPAC1-R mRNAs was very similar to that of PACAP binding sites, the concentration of VPAC1-R mRNA being much lower than that of PAC1-R mRNA. In contrast, intense expression of VPAC2-R mRNA was observed in brain regions other than germinative areas, such as the suprachiasmatic, ventral thalamic, and dorsolateral geniculate nuclei. The discrete localization of PACAP binding sites as well as PAC1-R and VPAC1-R mRNAs in neuroepithelia during embryonic life and postnatal development strongly suggests that PACAP, acting through PAC1-R and/or VPAC1-R, may play a crucial role in the regulation of neurogenesis in the rat brain.
TL;DR: In this article, a three-dimensional atom probe was used to study deformed steel wires obtained by cold drawing and dissolution kinetics were modelled semiquantitatively on the basis of thermodynamics and diffusion arguments.
Abstract: Heavily deformed pearlitic steel wires obtained by cold drawing have been investigated using a three-dimensional atom probe. Concentration profiles reveal the existence of pronounced gradients in the ferrite near ferrite-cementite interfaces. This indicates that cementite lamellae dissolve. Experiments are interpreted and dissolution kinetics are modelled semiquantitatively on the basis of thermodynamics and diffusion arguments. The dramatic increase in interface areas during drawing is considered as the driving force for dissolution through a Gibbs-Thomson effect. The relatively slow cooling of specimen from the temperature of drawing (100-300°C) to room temperature hence leads to the downhill diffusion of carbon from interfaces to the ferrite core. The kinetics equations are numerically solved in order to take into account the non-constant mobility of carbon during cooling. The model highlights the key parameters which drive dissolution and their influence on kinetics. In comparison with experiments, predicted dissolution rates appear, however, to be underestimated.
TL;DR: In this paper, a review of nanostructural features of nickel-based superalloys as revealed by Field-Ion Microscopy, Atom Probe (APFIM), and 3D Atom Probe are reviewed.
TL;DR: The content of this paper focuses on the computation of a new set of features allowing the classification of multioriented and multiscaled patterns based on the Fourier–Mellin Transform, which can solve the well known difficult problem of connected character recognition.
Abstract: In this paper, we consider the general problem of technical document interpretation, as applied to the documents of the French Telephonic Operator, France Telecom. More precisely, we focus the content of this paper on the computation of a new set of features allowing the classification of multioriented and multiscaled patterns. This set of invariants is based on the Fourier–Mellin Transform. The interests of this computation rely on the excellent classification rate obtained with this method and also on using this Fourier–Mellin transform within a “filtering mode”, with which we can solve the well known difficult problem of connected character recognition.
TL;DR: In this paper, the action of pressure on the bacterial membrane proteins is analyzed and the authors define membrane proteins as a target of high hydrostatic pressure treatments, which could allow an increase in the efficiency of treatments.
TL;DR: Female rats were repeatedly stressed for 10 periods of 15 min by the presence of a cat, at the 10th or the 19th gestational day and their long-term memory was altered and they exhibited an aversive behavior relative to wide areas.
TL;DR: SR-L is a safe and effective treatment of thyrotropinomas and avoids the drawbacks of the modes of administration of other somatostatin analogs, given three times daily.
Abstract: Somatostatin analogs have been shown to be effective for the treatment of TSH-secreting pituitary adenomas. However, their use in this indication is limited by the fact that available analogs require several daily sc injections. The present study was performed to evaluate the effects of a slow release formulation of the somatostatin analog lanreotide (SR-L) on both hormone secretion and tumor size and to assess the tolerance in a series of thyrotropinomas treated for 6 months. Eighteen patients with hyperthyroidism related to a TSH-secreting pituitary adenoma, evidenced by pituitary magnetic resonance imaging, were studied. After a basal assessment, each patient received 30 mg SR-L, im, every 14 days for 1 month. Then, according to the free T3 (fT3) plasma level measured, 9 of 18 patients were injected twice monthly, and 7 of 18 patients received SR-L every 10 days for 5 additional months. One patient was dismissed from the study in month 1 of the study for side-effects and another in month 3 for noncompliance to the protocol. Clinical and biological evaluations (plasma TSH, free alpha-subunit, fT4, fT3, and lanreotide levels) were performed before and in months 1, 3, and 6 of treatment. Pituitary magnetic resonance imaging and gallbladder ultrasonography were performed both at entry and at the end of the study. Clinical signs of hyperthyroidism improved within 1 month in all 16 evaluable patients. Mean (+/- SEM) plasma lanreotide levels reached 1.11 +/- 0.43 and 1.69 +/- 0.65 ng/mL in month 3 using 2 and 3 injections/month, respectively, then remained stable until the end of the study. During therapy, the plasma TSH level decreased from 2.72 +/- 0.32 to 1.89 +/-0.27 mU/L (P < 0.01), with parallel significant changes in free alpha-subunit. During the same period, plasma fT4 and fT3 levels decreased from 37.9 +/- 2.9 to 19.7 +/- 2.3 pmol/L (P < 0.01) and from 14.6 +/- 1.1 to 8.3 +/- 0.8 pmol/L (P < 0.01), respectively. No statistically significant change in mean adenoma size was observed after 6 months of treatment. Side-effects, including pain at the injection point, abdominal cramps, and diarrhea, were mild and transient and did not lead to interruption of the treatment. No gallstones occurred during the study. SR-L appears to be able to suppress clinical signs of hyperthyroidism in our series of patients with TSH-secreting pituitary adenomas. The analog also reduces plasma TSH and thyroid hormone levels, which were normalized in 13 of 16 cases. The effect was maintained throughout the treatment using 2 or 3 SR-L injections monthly without any problem of tolerance. We conclude that SR-L is a safe and effective treatment of thyrotropinomas and avoids the drawbacks of the modes of administration of other somatostatin analogs, given three times daily.
TL;DR: The number of therapeutic proteins successfully produced in plants is steadily increasing and is expected to grow even more rapidly in the future, while strategies to humanise plant N-glycans are now developed.
Abstract: The number of therapeutic proteins successfully produced in plants is steadily increasing and is expected to grow even more rapidly in the future. Most therapeutic proteins are glycoproteins and N-glycosylation is often essential for their stability, folding and biological activity. Recombinant glycoproteins of mammalian origin expressed in transgenic plants largely retain their biological activity. However, plants are not ideal for production of pharmaceutical proteins because they produce molecules with glycans that are not compatible with therapeutic applications in humans. As a consequence, strategies to humanise plant N-glycans are now developed. Some of these strategies involve the retention of the recombinant glycoprotein in the endoplasmic reticulum while others are related to the inhibition of endogenous Golgi glycosyltransferases or addition of new glycosyltransferases. Data on both the N-glycosylation of therapeutic glycoproteins produced in transgenic plants and current strategies to huma nise their N-glycosylation will be discussed in this review.
Journal Article•
TL;DR: In contrast to what is often expressed in the literature, reversible and irreversible solid(s)-solid(s) transitions in binary system of non-racemizable enantiomers are not always referred to as polymorphism as mentioned in this paper.
Abstract: In contrast to what is often expressed in the literature, reversible and irreversible solid(s)-solid(s) transitions in binary system of non-racemizable enantiomers are not always referred to as polymorphism. Order-disorder phenomena, miscibility gaps with critical temperatures and transitions in which three-phases or even four-phases are involved can also occur. In the case of reversibility, three-phase invariants such as eutectoid or peritectoid corresponding to the reversible formation or decomposition of racemic compounds are described. The heterogeneous equilibria are reviewed with or without miscibility in the solid state. Several four-phase invariants and order-disorder transitions are predicted.
TL;DR: In this paper, the dispersive and Strichartz inequalities on the Heisenberg group were proved by the analysis of Besov-type spaces on the group, and the results were extended to the general case.
Abstract: In this paper, we prove dispersive and Strichartz inequalities on the Heisenberg group. The proof involves the analysis of Besov-type spaces on the Heisenberg group.