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Ixodes ricinus Tick Lipocalins: Identification, Cloning, Phylogenetic Analysis and Biochemical Characterization
Jérme Beaufays, Beno?t Adam, Yves Decrem, Pierre-Paul Prév?t, Sébastien Santini, Robert Brasseur, Michel Brossard, Laurence Lins, Luc Vanhamme, Edmond Godfroid
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0003941
Abstract: Background During their blood meal, ticks secrete a wide variety of proteins that interfere with their host's defense mechanisms. Among these proteins, lipocalins play a major role in the modulation of the inflammatory response. Methodology/Principal Findings Screening a cDNA library in association with RT-PCR and RACE methodologies allowed us to identify 14 new lipocalin genes in the salivary glands of the Ixodes ricinus hard tick. A computational in-depth structural analysis confirmed that LIRs belong to the lipocalin family. These proteins were called LIR for “Lipocalin from I. ricinus” and numbered from 1 to 14 (LIR1 to LIR14). According to their percentage identity/similarity, LIR proteins may be assigned to 6 distinct phylogenetic groups. The mature proteins have calculated pM and pI varying from 21.8 kDa to 37.2 kDa and from 4.45 to 9.57 respectively. In a western blot analysis, all recombinant LIRs appeared as a series of thin bands at 50–70 kDa, suggesting extensive glycosylation, which was experimentally confirmed by treatment with N-glycosidase F. In addition, the in vivo expression analysis of LIRs in I. ricinus, examined by RT-PCR, showed homogeneous expression profiles for certain phylogenetic groups and relatively heterogeneous profiles for other groups. Finally, we demonstrated that LIR6 codes for a protein that specifically binds leukotriene B4. Conclusions/Significance This work confirms that, regarding their biochemical properties, expression profile, and sequence signature, lipocalins in Ixodes hard tick genus, and more specifically in the Ixodes ricinus species, are segregated into distinct phylogenetic groups suggesting potential distinct function. This was particularly demonstrated by the ability of LIR6 to scavenge leukotriene B4. The other LIRs did not bind any of the ligands tested, such as 5-hydroxytryptamine, ADP, norepinephrine, platelet activating factor, prostaglandins D2 and E2, and finally leukotrienes B4 and C4.
Variability and Action Mechanism of a Family of Anticomplement Proteins in Ixodes ricinus
Bernard Couvreur, Jérme Beaufays, Cédric Charon, Kathia Lahaye, Fran?ois Gensale, Valérie Denis, Beno?t Charloteaux, Yves Decrem, Pierre-Paul Prév?t, Michel Brossard, Luc Vanhamme, Edmond Godfroid
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0001400
Abstract: Background Ticks are blood feeding arachnids that characteristically take a long blood meal. They must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. This is achieved by expressing batteries of salivary proteins coded by multigene families. Methodology/Principal Findings We report the in-depth analysis of a tick multigene family and describe five new anticomplement proteins in Ixodes ricinus. Compared to previously described Ixodes anticomplement proteins, these segregated into a new phylogenetic group or subfamily. These proteins have a novel action mechanism as they specifically bind to properdin, leading to the inhibition of C3 convertase and the alternative complement pathway. An excess of non-synonymous over synonymous changes indicated that coding sequences had undergone diversifying selection. Diversification was not associated with structural, biochemical or functional diversity, adaptation to host species or stage specificity but rather to differences in antigenicity. Conclusions/Significance Anticomplement proteins from I. ricinus are the first inhibitors that specifically target a positive regulator of complement, properdin. They may provide new tools for the investigation of role of properdin in physiological and pathophysiological mechanisms. They may also be useful in disorders affecting the alternative complement pathway. Looking for and detecting the different selection pressures involved will help in understanding the evolution of multigene families and hematophagy in arthropods.
Editorial: Is Electroconvulsive Therapy a Therapy with Future?  [PDF]
Jérme Palazzolo
Open Journal of Depression (OJD) , 2013, DOI: 10.4236/ojd.2013.23004
Abstract: Editorial: Is Electroconvulsive Therapy a Therapy with Future?
Ir-LBP, an Ixodes ricinus Tick Salivary LTB4-Binding Lipocalin, Interferes with Host Neutrophil Function
Jérme Beaufays, Beno?t Adam, Catherine Menten-Dedoyart, Laurence Fievez, Amélie Grosjean, Yves Decrem, Pierre-Paul Prév?t, Sébastien Santini, Robert Brasseur, Michel Brossard, Michel Vanhaeverbeek, Fabrice Bureau, Ernst Heinen, Laurence Lins, Luc Vanhamme, Edmond Godfroid
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0003987
Abstract: Background During their blood meal, ticks secrete a wide variety of proteins that can interfere with their host's defense mechanisms. Among these proteins, lipocalins play a major role in the modulation of the inflammatory response. Methodology/Principal Findings We previously identified 14 new lipocalin genes in the tick Ixodes ricinus. One of them codes for a protein that specifically binds leukotriene B4 with a very high affinity (Kd: ±1 nM), similar to that of the neutrophil transmembrane receptor BLT1. By in silico approaches, we modeled the 3D structure of the protein and the binding of LTB4 into the ligand pocket. This protein, called Ir-LBP, inhibits neutrophil chemotaxis in vitro and delays LTB4-induced apoptosis. Ir-LBP also inhibits the host inflammatory response in vivo by decreasing the number and activation of neutrophils located at the tick bite site. Thus, Ir-LBP participates in the tick's ability to interfere with proper neutrophil function in inflammation. Conclusions/Significance These elements suggest that Ir-LBP is a “scavenger” of LTB4, which, in combination with other factors, such as histamine-binding proteins or proteins inhibiting the classical or alternative complement pathways, permits the tick to properly manage its blood meal. Moreover, with regard to its properties, Ir-LBP could possibly be used as a therapeutic tool for illnesses associated with an increased LTB4 production.
Urban Wastewater Treatment by Adsorption of Organic Matters on Modified Bentonite by (Iron-Aluminum)  [PDF]
Me?abih Zohra, Jérme Rose, Daniel Borschneck
Journal of Encapsulation and Adsorption Sciences (JEAS) , 2014, DOI: 10.4236/jeas.2014.43008
Abstract: In this research, the natural bentonite clay (from Maghnia, western Algeria) was purified (Na+- montmorillonite, CEC = 91 meq/100 g), noted (puri.bent) and modified with mixed hydroxy-Fe-Al (FeAl-PILC). The purified bentonite clay and FeAl-PILC were heated at 383 K for 2 hr and characte-rized by the chemical analyses data, XRD, and N2 adsorption to 77 K techniques. Puri.bent and FeAl-PILC were applied to fix the organic matter (OM) present in urban wastewater from the city of Sidi Bel-Abbes (western Algeria). The adsorption of organic matter was followed by spectro-photometry at 470 nm, and the adsorption data were a good fit with Freundlich isotherm for pu-ri.bent but for FeA-lPILC, were well fit by Elovitch isotherm model. The maximum adsorption ca-pacity (qm) was 571.6 mg/g for puri.bent and 1120.69 mg/g for FeAl-PLC. The degree of OM removal was 67% for puri.bent and 97% for FeAl-PILC. FeAl-PILC can be considered as a promising adsorbent for the removal of OM from wastewater.
Fluorescence Enhancement Factors on Optical Antennas: Enlarging the Experimental Values without Changing the Antenna Design
Jérme Wenger
International Journal of Optics , 2012, DOI: 10.1155/2012/828121
Abstract: Plasmonic antennas offer promising opportunities to control the emission of quantum objects. As a consequence, the fluorescence enhancement factor is widely used as a figure of merit for a practical antenna realization. However, the fluorescence enhancement factor is not an intrinsic property of the antenna. It critically depends on several parameters, some of which are often disregarded. In this contribution, I explore the influence of the setup collection efficiency, emitter's quantum yield, and excitation intensity. Improperly setting these parameters may significantly alter the enhancement values, leading to potential misinterpretations. The discussion is illustrated by an antenna example of a nanoaperture surrounded by plasmonic corrugations. 1. Introduction Plasmonic antennas are receiving a large interest to interface light with nanoscale quantum emitters on dimensions much beyond the optical wavelength [1, 2]. Recent developments involve squeezing light into nanoscale volumes [3], enhancing the excitation and emission rate of individual emitters [4–8], tuning the luminescence spectrum [9, 10], polarization [11], and directivity properties [12–16]. Several plasmonic systems are being investigated to enhance the luminescence emission of fluorescent molecules or quantum dots, such as metallic nanoparticles [4, 5, 17–20], core-shell particles [21], thin films [22, 23], nanoantennas [6, 7, 15, 24], nanowires [16], nanoporous gold [25], nanopockets [26], metallic gratings [27], nanoaperture arrays [28], and single nanoapertures [29, 30]. A general review on surface-enhanced fluorescence can be found in [31]. A natural question while performing experiments on nanoantenna-enhanced luminescence deals with the quantification of the luminescence enhancement factor , which is commonly defined as the ratio of the detected radiation power per emitter with the antenna to the reference radiation power per emitter without the antenna. determines how many extra photons are detected for each emitter thanks to the use of the optical antenna. It is well known that this factor critically depends on several parameters: the antenna material and geometry, its spectral resonance, and overlap with the emitter’s absorption and luminescence spectra, as well as the emitter’s orientation and location respective to the antenna [32]. These many parameters often hide the influence of other parameters: the collection efficiency used in the experiments, the emitter’s quantum yield in the absence of the antenna, and the excitation intensity respective to the saturation process.
How tissue injury alarms the immune system and causes a systemic inflammatory response syndrome
Jérme Pugin
Annals of Intensive Care , 2012, DOI: 10.1186/2110-5820-2-27
Abstract:
Carney complex (CNC)
Jérme Bertherat
Orphanet Journal of Rare Diseases , 2006, DOI: 10.1186/1750-1172-1-21
Abstract: Carney complex.The complex of cardiac myxomas, endocrine overactivity and spotty pigmentation.The Carney complex (CNC) was first described in 1985 by J. Aidan Carney, as the combination of myxomas, spotty pigmentation and endocrine overactivity [1]. It is defined by the association of multiple endocrine neoplasia and cardiocutaneous manifestations. Patients previously characterized as LAMB (lentigineses, atrial myxoma, mucocutaneous myxoma, blue nevi) or NAME (nevi, atrial myxoma, myxoid neurofibroma, ephelide) could be considered as having Carney complex. Numerous organs may be involved in CNC and the manifestations vary greatly among patients. Some of them are quite specific, such as primary pigmented nodular disease (PPNAD), while others show little specificity, such as thyroid nodes or blue nevi. It is generally assumed that a patient presenting with two or more of the manifestations listed in Table 1 would be diagnosed as having Carney complex. This table lists the most frequent features of CNC and their estimated frequency [according to references [1,3-5,8] and our personal observations]. The incidence of each manifestation depends on its presentation and might not reflect true prevalence. For instance, according to autopsy studies PPNAD is a constant feature in CNC patients [8], however, reports of Cushing syndrome in the literature indicate that only 25 to 45 % of CNC patients have PPNAD. It has been established that at least two of these manifestations need to be present to confirm the diagnosis of CNC. If the patient has a germline PRKAR1A mutation and/or a first-degree relative affected by CNC, a single manifestation is sufficient for the diagnosis.CNC is a rare disease. About 500 patients have been registered by the NIH-Mayo Clinic (USA) and the Cochin center (France) [2]. Cumulative reports from these centers, plus information from the Cornell center in New York, indicate that there are about 160 index cases of CNC presently known [3-6].The manifestatio
"The Pyrenees are not hollow": the mountain as a boundary object
Lamy, Jérme;
História, Ciências, Saúde-Manguinhos , 2009, DOI: 10.1590/S0104-59702009000300014
Abstract: in toulouse, around 1850, a controversy about the structure of the pyrenees pitted observatory director frederic petit against geology professor alexandre leymerie. the object of the debate was an assumption formulated by petit: that the inside of the pyrenees was practically hollow. this proposal was based on work that petit initiated in order to determine the latitude of toulouse. the debates, which took place within the toulouse academy of science and also in local newspapers, illustrate the organization of disciplinary spaces in the nineteenth century. petit defended his research method based on calculation; the geologist's perspective was from the field. the emergence of the less mathematical science of geology came up against nineteenth-century astronomical practices, centered on calculation. dissected by calculation or by visual observation, the mountain was an object of controversy from the perspective of distinct scientific practices.
La Grande Peur dans la montagne ou o nascimento de uma lenda
Berney, Jérme;
Alea : Estudos Neolatinos , 2004, DOI: 10.1590/S1517-106X2004000200008
Abstract: ramuz was very fond of alpine legends and he was inspired by a number of them in his texts. this paper examines the case of la grande peur dans la montagne (1926), showing that the novel is crossed by several legendary common places, such as the devilish hunter and the glacial purgatory where damned souls wander. in the fashion of some of maupassant's novellas, the main character of la grande peur, joseph, faces supernatural events which gradually draw him into an eerie, fantastic, even phantasmatic, universe. on the other hand, the ending of the novel, at least in the original edition, may let one think that the whole of the narrative is a legend.
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