Last 7 days
Bookmark and Share    
Full Text
Peer Reviewed
See detailWidespread activity of multiple lineages of Usutu virus, western Europe, 2016.
Cadar, Daniel; Luhken, Renke; van der Jeugd, Henk et al

in Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin (2017), 22(4),

In the summer of 2016, Belgium, France, Germany and the Netherlands reported widespread Usutu virus (USUV) activity based on live and dead bird surveillance. The causative USUV strains represented four ... [more ▼]

In the summer of 2016, Belgium, France, Germany and the Netherlands reported widespread Usutu virus (USUV) activity based on live and dead bird surveillance. The causative USUV strains represented four lineages, of which two putative novel lineages were most likely recently introduced into Germany and spread to other western European countries. The spatial extent of the outbreak area corresponded with R0 values > 1. The occurrence of the outbreak, the largest USUV epizootic registered so far in Europe, allowed us to gain insight in how a recently introduced arbovirus with potential public health implications can spread and become a resident pathogen in a naive environment. Understanding the ecological and epidemiological factors that drive the emergence or re-emergence of USUV is critical to develop and implement timely surveillance strategies for adequate preventive and control measures. Public health authorities, blood transfusion services and clinicians in countries where USUV was detected should be aware of the risk of possible USUV infection in humans, including in patients with unexplained encephalitis or other neurological impairments, especially during late summer when mosquito densities peak. [less ▲]

Detailed reference viewed: 15 (1 ULg)
Full Text
Peer Reviewed
See detailOrganic Farming and Small-Scale Farmers: Main Opportunities and Challenges
Jouzi, Zeynab; Azadi, Hossein ULg; Taheri, Fatemeh et al

in Ecological Economics (2017), 132(February 2017), 144-154

Producing enough food to meet the needs of a growing population has always been the greatest concern of food policy-makers around the world. Given the increasing attention to organic farming (OF), we ... [more ▼]

Producing enough food to meet the needs of a growing population has always been the greatest concern of food policy-makers around the world. Given the increasing attention to organic farming (OF), we conducted this study to investigate the main opportunities and challenges of the food production system of small-scale farmers in developing countries with an emphasis on their livelihoods. The study showed that the most significant advantages of OF are environmental protection and a higher resilience to environmental changes, increasing farmers' income and reducing external input cost, enhancing social capacity and increasing employment opportunities. A s well as enhancing food security primarily by increasing the food purchasing power of local people. However, the main challenges of this food production system include lower yields in comparison to conventional systems, difficulties with soil nutrient management, certification and market barriers, and the educational and research needs of small-holders. The paper concludes that even though OF might present some significant challenges to small-scale farmers, it could/should still be considered as a part of the solution and means of improving their livelihoods. [less ▲]

Detailed reference viewed: 47 (6 ULg)
Full Text
See detailProcédure pénale
Michiels, Olivier ULg

Learning material (2017)

Detailed reference viewed: 311 (123 ULg)
Peer Reviewed
See detailUne architecture de frontières : les monastères des annonciades célestes dans les Trois-Evêchés (17e-18e siècles)
Piront, Julie ULg

in Bourdieu, Catherine (Ed.) Vie religieuse féminine dans les Trois-Evêchés : vocations, missions et cadres d'existence (2017)

Les Trois-Evêchés ont été un terrain fertile pour les congrégations féminines aux 16e-18e siècles puisqu'ils ont vu la naissance de projets religieux conjuguée à une installation massive de « nouveaux ... [more ▼]

Les Trois-Evêchés ont été un terrain fertile pour les congrégations féminines aux 16e-18e siècles puisqu'ils ont vu la naissance de projets religieux conjuguée à une installation massive de « nouveaux ordres » nés ou réformés dans le sillage du concile de Trente. Fondées en Italie au début du 17e siècle, les annonciades célestes se sont implantées majoritairement sur la « dorsale catholique ». Au cœur de ce territoire de frontières, les Trois-Évêchés occupent une position géographique, politique et religieuse incontournable. Dans le cadre de cette journée d’études, il s’agira d’interroger les spécificités éventuelles des cinq monastères que les annonciades célestes firent édifier dans les Trois-Évêchés en les comparant à l’ensemble de la production architecturale de l’ordre en Europe aux 17e et 18e siècles. En allant plus loin, nous verrons comment les représentations mentales de ces édifices ont participé à la genèse de l’identité de l’ordre, notamment grâce aux sources écrites et iconographiques qui en témoignent. [less ▲]

Detailed reference viewed: 20 (0 ULg)
Full Text
Peer Reviewed
See detailMembrane Interactions of Natural Cyclic Lipodepsipeptides of the Viscosin Group
Geudens, Niels; Nasir, Mehmet Nail ULg; Crowet, Jean-Marc ULg et al

in Biochimica et Biophysica Acta - Biomembranes (2017), 1859(3), 331-339

Many Pseudomonas spp. produce cyclic lipodepsipeptides (CLPs), which, besides their role in biological functions such as motility, biofilm formation and interspecies interactions, are antimicrobial. It ... [more ▼]

Many Pseudomonas spp. produce cyclic lipodepsipeptides (CLPs), which, besides their role in biological functions such as motility, biofilm formation and interspecies interactions, are antimicrobial. It has been established that interaction with the cellular membrane is central to the mode of action of CLPs. In this work, we focus on the CLPs of the so-called viscosin group, aiming to assess the impact of the main structural variations observed within this group on both the antimicrobial activity and the interaction with model membranes. The antimicrobial activity of viscosin, viscosinamide A, WLIP and pseudodesmin A were all tested on a broad panel of mainly Gram-positive bacteria. Their capacity to permeabilize or fuse PG/PE/cardiolipin model membrane vesicles is assessed using fluorescent probes. We find that the Glu2/Gln2 structural variation within the viscosin group is the main factor that influences both the membrane permeabilization properties and the minimum inhibitory concentration of bacterial growth, while the configuration of the Leu5 residue has no apparent effect. The CLPmembrane interactions were further evaluated using CD and FT-IR spectroscopy on model membranes consisting of PG/PE/cardiolipin or POPC with or without cholesterol. In contrast to previous studies, we observe no conformational change upon membrane insertion. The CLPs interact both with the polar heads and aliphatic tails of model membrane systems, altering bilayer fluidity, while cholesterol reduces CLP insertion depth [less ▲]

Detailed reference viewed: 44 (9 ULg)
Full Text
Peer Reviewed
See detailTwo new species in the Micarea prasina group from Western Europe
van den Boom, Pieter P. G.; Brand, A. Maarten; Coppins, Brian J. et al

in Lichenologist (2017), 49(1), 13-25

Detailed reference viewed: 23 (3 ULg)
Full Text
Peer Reviewed
See detailShip collision analysis on Offshore Wind Turbine monopile foundations
Bela, Andreea ULg; Le Sourne, Hervé; Buldgen, Loïc ULg et al

in Marine Structures (2017), 51

An offshore wind farm covers a large maritime area and the site can be located close to traffic lanes of commercial and passenger ships, which may lead to possible collision events. The work presented in ... [more ▼]

An offshore wind farm covers a large maritime area and the site can be located close to traffic lanes of commercial and passenger ships, which may lead to possible collision events. The work presented in this paper aimed to understand both the crushing behavior and the nacelle dynamics of a predefined monopile offshore wind turbine when impacted by a ship. Another objective was to deeply investigate the influence of various parameters like ship impact velocity and location, wind direction, soil stiffness and deformability of the striking ship. First, nonlinear numerical simulations of ship - Offshore Wind Turbine (OWT) collisions have been carried out with a rigid striking ship for a better understanding of the OWT’s structural behaviour during collision. Different configurations for the wind turbine’s structure have been used in order to highlight the modifications in behaviour induced by changing the soil conditions or the loading scenario. The resulting resistant force and internal energies have been compared as well as the tower top (nacelle) displacements and accelerations. Then, another series of simulations have been performed with a deformable ship in order to investigate the influence of the deformability of the striking ship on the OWT’s behaviour. It is worth noting that all these numerical results will further serve to fix the hypotheses for the development of a simplified tool based on analytical formulations. [less ▲]

Detailed reference viewed: 42 (8 ULg)
Full Text
Peer Reviewed
See detailCXCL12 mediates glioblastoma resistance to radiotherapy in the subventricular zone.
Goffart, Nicolas ULg; Lombard, Arnaud; Lallemand, François ULg et al

in Neuro-Oncology (2017), 19(1), 66-77

BACKGROUND: Patients with glioblastoma (GBM) have an overall median survival of 15 months despite multimodal therapy. These catastrophic survival rates are to be correlated to systematic relapses that ... [more ▼]

BACKGROUND: Patients with glioblastoma (GBM) have an overall median survival of 15 months despite multimodal therapy. These catastrophic survival rates are to be correlated to systematic relapses that might arise from remaining glioblastoma stem cells (GSCs) left behind after surgery. In this line, it has recently been demonstrated that GSCs are able to escape the tumor mass and preferentially colonize the adult subventricular zone (SVZ). At a distance from the initial tumor site, these GSCs might therefore represent a high-quality model of clinical resilience to therapy and cancer relapses as they specifically retain tumor-initiating abilities. METHOD: While relying on recent findings that have validated the existence of GSCs in the human SVZ, we questioned the role of the SVZ niche as a potential GSC reservoir involved in therapeutic failure. RESULTS: Our results demonstrate that (i) GSCs located in the SVZ are specifically resistant to radiation in vivo, (ii) these cells display enhanced mesenchymal roots that are known to be associated with cancer radioresistance, (iii) these mesenchymal traits are specifically upregulated by CXCL12 (stromal cell-derived factor-1) both in vitro and in the SVZ environment, (iv) the amount of SVZ-released CXCL12 mediates GBM resistance to radiation in vitro, and (v) interferes with the CXCL12/CXCR4 signalling system, allowing weakening of the tumor mesenchymal roots and radiosensitizing SVZ-nested GBM cells. CONCLUSION: Together, these data provide evidence on how the adult SVZ environment, through the release of CXCL12, supports GBM therapeutic failure and potential tumor relapse. [less ▲]

Detailed reference viewed: 35 (14 ULg)
Full Text
Peer Reviewed
See detailThe somatotrope Growth Hormone-Releasing Hormone/Growth Hormone/Insulin-like Growth Factor 1 axis in immunoregulation and immunosenescence
Bodart, Gwennaëlle ULg; Farhat, Khalil; RENARD, Jeanne de Chantal ULg et al

in Savino, Wilson; Guaraldi, Federica (Eds.) Endocrine Immunology (2017)

Most scientific reports debate the thymotropic and immuno-stimulating properties of the somato- trope growth hormone-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor (IGF)-1 axis ... [more ▼]

Most scientific reports debate the thymotropic and immuno-stimulating properties of the somato- trope growth hormone-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor (IGF)-1 axis, but there is still some disagreement about the physiological role of this axis in basal conditions. Moreover, some authors have hypothesized that the physiological role of the somato- trope axis only appears in stressful conditions (such as sepsis or infective and inflammatory diseases). This chapter will provide an extended overview of the expression of the components (signals and receptors) of the somatotrope axis and their properties on cells of the innate and adaptive immune system. It will also summarize some clinical studies suggesting a benefit for a short-term GH treat- ment in acute immunodeficiencies, and the importance of GH supplementation in adult GH defi- ciency. A new transgenic mouse model, the hypothalamic GHRH-deficient (Ghrh–/–) mouse, which exhibits a severe deficiency of the somatotrope axis, will be presented since it will be of great help in further deciphering the regulation by the GHRH/GH/IGF-1 axis on both immune development and function. Finally, we will discuss the implication of aging-related somatopause in relation to the general context of Immunosenescence. [less ▲]

Detailed reference viewed: 43 (5 ULg)
Full Text
Peer Reviewed
See detailLe choix du liégeois. Dîmègne de Louis Remacle
Baiwir, Esther ULg; Biquet, Stéphanie ULg

in Baiwir, Esther; Biquet, Stéphanie (Eds.) Petite anthologie subjective de littérature wallonne (2017)

Lecture et commentaire du seul poème en liégeois de Louis Remacle, "Dîmègne".

Detailed reference viewed: 46 (10 ULg)
Full Text
Peer Reviewed
See detailSampling only ten microliters of whole blood for the quantification of poorly soluble drugs: Itraconazole as case study
Thiry, Justine ULg; Evrard, Brigitte ULg; Nys, Gwenaël ULg et al

in Journal of Chromatography. A (2017), 1479

Nowadays in animal studies, it is important to comply with the so-called Three Rs rule by replacing or reducing the number of tested animals. Volumetric absorptive microsampling (VAMS) can be used to ... [more ▼]

Nowadays in animal studies, it is important to comply with the so-called Three Rs rule by replacing or reducing the number of tested animals. Volumetric absorptive microsampling (VAMS) can be used to collect small quantities (10 or 20 µL) of whole blood, thereby limiting the amount of animals needed. In this study, a quantitative method was developed and subsequently validated for the poorly soluble drug itraconazole (ITZ) using VAMS and ultra-high performance liquid chromatography (UHPLC) coupled to tandem mass spectrometry (MS). A proof of concept study showed that the optimized method is applicable to test the bioavailability of drug formulations containing ITZ. Using VAMS, smaller blood volumes can be taken per sampling point (10-20 µL instead of the conventional 0.2-0.5 mL) avoiding the sacrifice of animals. Moreover, the same rats can be used to compare different drug formulations which strengthens the validity of the results. In long-term bioavailability studies, it is necessary to guarantee the stability of the tested drugs supported on VAMS devices. In this study, we show that ITZ was only stable for 24 hours after collection with VAMS, but for at least two weeks by the storage of extracted samples at -80°C. [less ▲]

Detailed reference viewed: 21 (7 ULg)
Full Text
Peer Reviewed
See detailInteractive effects of ultraviolet radiation and thermal stress on two reef-building corals
Courtial, Lucile; Roberty, Stéphane ULg; Shick, Malcom et al

in Limnology and Oceanography (2017)

Detailed reference viewed: 24 (2 ULg)
Full Text
Peer Reviewed
See detailAssessing inter- and intramolecular continuous-flow strategies towards methylphenidate (Ritalin) hydrochloride
Gerardy, Romaric ULg; Winter, Marc; Vizza, Alessandra et al

in Reaction Chemistry and Engineering (2017)

The batch-to-flow translation of inter- and intramolecular strategies for the diastereoselective preparation of the active pharmaceutical ingredient threo-methylphenidate hydrochloride is presented. Both ... [more ▼]

The batch-to-flow translation of inter- and intramolecular strategies for the diastereoselective preparation of the active pharmaceutical ingredient threo-methylphenidate hydrochloride is presented. Both inter- and intramolecular strategies imply the telescoping of multiple processing steps and the generation of unstable diazo species under continuous-flow conditions. The intermolecular strategy relies on an unprecedented continuous-flow Rh-catalyzed intermolecular C–H carbene insertion, providing enriched threo-N-Boc methylphenidate in 38% or 19% isolated yield according to sequential or fully telescoped processes, respectively. Quantitative Boc-deprotection is carried out off-line. The intramolecular strategy relies on a continuous-flow thermal intramolecular C–H carbene insertion, providing enriched threo-methylphenidate hydrochloride in 70% isolated yield. A continuous-flow photochemical alternative is also presented. The critical step of the most promising intramolecular strategy is implemented on the mesoscale in a pilot-scale continuous-flow reactor. [less ▲]

Detailed reference viewed: 28 (6 ULg)
Full Text
Peer Reviewed
See detailFaire les courses au quotidien. L’approvisionnement alimentaire d’un groupe de migrantes marocaines en Italie en temps de crise
Mescoli, Elsa ULg

in Matagne, Geoffroy; Van Ingelgom, Virginie (Eds.) Politiques de crise, crises du politique (2017)

La crise généralisée qui, depuis quelques années, a affaibli les économies de nombre d’états, a eu des conséquences sur la typologie des migrations internationales : les trajectoires, les projets, les ... [more ▼]

La crise généralisée qui, depuis quelques années, a affaibli les économies de nombre d’états, a eu des conséquences sur la typologie des migrations internationales : les trajectoires, les projets, les destinations, les départs se sont modifiés en fonction de nouveaux facteurs auxquels les individus et les groupes étaient confrontés . A côté de ces macro-dynamiques globales, la crise a également engendré des changements dans la vie quotidienne des migrants lorsqu’ils étaient déjà partis et qu’ils s’étaient déjà installés ailleurs. Dans ce cadre, ma contribution vise à analyser les pratiques d’approvisionnement alimentaire d’un groupe de migrantes marocaines en Italie mettant en place des stratégies pour faire face aux conséquences concrètes de la crise économique (notamment la diminution de leur pouvoir d’achat en conséquence de leur précarité professionnelle). Au travers de plusieurs déplacements dans la ville où elles habitaient et de la mobilisation des réseaux familiaux alimentant des circuits informels d’échange de biens, ces femmes satisfaisaient leurs différentes exigences – parmi lesquelles le désir de performer des préparations propres à leur mémoire incorporée – tout en répondant aux contraintes économiques déterminées par la crise. Je vais ainsi démontrer qu’en dépit des difficultés rencontrées, ces femmes arrivaient à exercer une agency dans le nouvel espace vécu et à se positionner de façon active au travers de leurs choix et conduites quotidiennes. [less ▲]

Detailed reference viewed: 27 (2 ULg)
Full Text
Peer Reviewed
See detailT2-weighted MRI signal intensity as a predictor of hormonal and tumoral responses to somatostatin receptor ligands in acromegaly: a perspective.
Potorac, Iulia ULg; Beckers, Albert ULg; BONNEVILLE, Jean-François ULg

in Pituitary (2017), 20(1), 116-120

T2-weighted MRI signal intensity of GH-secreting pituitary adenomas is gaining recognition as a marker of disease characteristics and may be a predictor of response to treatment of acromegaly. Adenomas ... [more ▼]

T2-weighted MRI signal intensity of GH-secreting pituitary adenomas is gaining recognition as a marker of disease characteristics and may be a predictor of response to treatment of acromegaly. Adenomas that are T2-hypointense are more common, are smaller and are less likely to invade the cavernous sinus compared to the T2-iso and hyperintense tumors. T2-hypointense tumors are also accompanied by higher IGF1 values at baseline. When presurgical somatostatin receptor ligand (SRL) therapy is administered, T2-hypointense adenomas have better hormonal responses and have greater tumor shrinkage. Adjuvant SRL therapy of patients with T2-hypointense tumors that are uncured by surgery is also associated with a better hormonal response. We review the studies that have dealt with the T2-weighted signal intensity of GH-secreting pituitary tumors and elaborate on the details and nuances of this promising avenue of research. [less ▲]

Detailed reference viewed: 1 (0 ULg)
Full Text
Peer Reviewed
See detailPrevalence of Concomitant Bone and Muscle Wasting in Elderly Women from the SarcoPhAge Cohort: Preliminary Results.
Locquet, Médéa ULg; Beaudart, Charlotte ULg; Reginster, Jean-Yves ULg et al

in Journal of Frailty & Aging (2017), 6(1), 18-23

BACKGROUND: Recent studies suggest that bone and muscle wasting are closely interconnected. OBJECTIVE: The aim was of this study is to assess the prevalence of osteoporosis in a population of women ... [more ▼]

BACKGROUND: Recent studies suggest that bone and muscle wasting are closely interconnected. OBJECTIVE: The aim was of this study is to assess the prevalence of osteoporosis in a population of women diagnosed with sarcopenia. Participants, setting and design: We analyzed cross-sectional data of women, aged 65 years and above, for whom bone mineral density was available at the time of inclusion in the SarcoPhAge (Sarcopenia and Physical impairment with advancing Age) cohort, an ongoing prospective study with the aim to assess consequences of sarcopenia. MEASUREMENTS: Muscle strength was evaluated with a hydraulic hand-dynamometer, appendicular lean mass and bone mineral density by Dual-Energy X-Ray Absorptiometry and physical performance by the Short Physical Performance Battery test (SPPB). Sarcopenia was diagnosed according to the European Working Group on Sarcopenia in Older People definition, i.e. a low muscle mass plus either low muscle strength or low physical performance. A bone mineral density T-score equal to or below -2.5SD at the lumbar spine, at the total hip or at the femoral neck was used to define osteoporosis (World Health Organization definition). RESULTS: A total of 126 women aged 74.38+/-6.32 years were included. Among them, 26 were assessed with sarcopenia (20.6%) and 34 (27.0%) with osteoporosis. There were more osteoporotic women among sarcopenic subjects (46.1%) than among non-sarcopenic subjects (22.0%) (p-value=0.011). A significant lower appendicular lean mass index was observed in osteoporotic women (p-value=0.025). We also observed, in osteoporotic subjects, a lower muscle strength (p-value=0.023). Numerical values of bone mineral density were lower in the sarcopenic population but the differences did not reach the level of statistical significance. CONCLUSION: Our study demonstrated that muscle mass and strength are lower in patients with osteoporosis. Prospective changes in bone and muscle mass will be investigated during the follow-up of our cohort. [less ▲]

Detailed reference viewed: 13 (2 ULg)
Full Text
Peer Reviewed
See detailA comparative study of guided vs pure self-treatment for premature ejaculation
Kempeneers, Philippe ULg; ANDRIANNE, Robert ULg; Cuddy, Marion et al

in Sexual and Relationship Therapy (2017)

Self-treatments have previously shown some efficacy in treating premature ejaculation (PE). It has been hypothesized that adding professional support to cognitive-behaviour bibliotherapy could improve ... [more ▼]

Self-treatments have previously shown some efficacy in treating premature ejaculation (PE). It has been hypothesized that adding professional support to cognitive-behaviour bibliotherapy could improve self-treatment outcomes. Therefore, the aim of this study was to compare treatment outcomes for participants with PE who used bibliotherapy alone (pure self-treatment) versus those who used the bibliotherapy with brief support from a health professional (guided self-treatment). Health professionals were not experienced sex therapists, but had attended a short training session in order to equip them to support the self-help process. 135 men reporting difficulties with PE were recruited between February and June 2013. Seventy-one (52.59%) completed the protocol: 37 in the pure self-treatment condition, 34 in the guided self-treatment condition. Thirty-five participants (50%) met criteria for ISSM definition of lifelong PE, 14 (20%) for acquired PE, and 22 (30%) presented other forms of PE complaints. At 4-8 months post-treatment, improvements were found in both groups and in each subtype of PE on self-reported measures of sexual functioning and sexual cognitions. Univariate analyses indicated slightly greater treatment effects in the guided self-treatment group, but multivariate tests failed to identify a significant effect of therapist support. These mixed findings raise questions regarding the amount and quality of therapist input used in this study, and also about a possible ceiling effect of cognitive-behaviour therapy for PE. [less ▲]

Detailed reference viewed: 33 (2 ULg)
Full Text
Peer Reviewed
See detailThiamine and benfotiamine prevent stress-induced suppression of hippocampal neurogenesis in mice exposed to predation without affecting brain thiamine diphosphate levels
Vignisse, Julie ULg; Sambon, Margaux ULg; Gorlova, Anna et al

in Molecular and Cellular Neuroscience (2017), 82

Thiamine is essential for normal brain function and its deficiency causes metabolic impairment, specific lesions, oxidative damage and reduced adult hippocampal neurogenesis (AHN). Thiamine precursors ... [more ▼]

Thiamine is essential for normal brain function and its deficiency causes metabolic impairment, specific lesions, oxidative damage and reduced adult hippocampal neurogenesis (AHN). Thiamine precursors with increased bioavailability, especially benfotiamine, exert neuroprotective effects not only for thiamine deficiency (TD), but also in mouse models of neurodegeneration. As it is known that AHN is impaired by stress in rodents, we exposed C57BL6/J mice to predator stress for 5 consecutive nights and studied the proliferation (number of Ki67-positive cells) and survival (number of BrdU-positive cells) of newborn immature neurons in the subgranular zone of the dentate gyrus. In stressed mice, the number of Ki67- and BrdU-positive cells was reduced compared to non-stressed animals. This reduction was prevented when the mice were treated (200 mg/kg/day in drinking water for 20 days) with thiamine or benfotiamine, that were recently found to prevent stress-induced behavioral changes and glycogen synthase kinase-3β (GSK-3β) upregulation in the CNS. Moreover, we show that thiamine and benfotiamine counteract stress-induced bodyweight loss and suppress stress-induced anxiety-like behavior. Both treatments induced a modest increase in the brain content of free thiamine while the level of thiamine diphosphate (ThDP) remained unchanged, suggesting that the beneficial effects observed are not linked to the role of this coenzyme in energy metabolism. Predator stress increased hippocampal protein carbonylation, an indicator of oxidative stress. This effect was antagonized by both thiamine and benfotiamine. Moreover, using cultured mouse neuroblastoma cells, we show that in particular benfotiamine protects against paraquat-induced oxidative stress. We therefore hypothesize that thiamine compounds may act by boosting anti-oxidant cellular defenses, by a mechanism that still remains to be unveiled. Our study demonstrates, for the first time, that thiamine and benfotiamine prevent stress-induced inhibition of hippocampal neurogenesis and accompanying physiological changes. The present data suggest that thiamine precursors with high bioavailability might be useful as a complementary therapy in several neuropsychiatric disorders. [less ▲]

Detailed reference viewed: 25 (6 ULg)
Full Text
Peer Reviewed
See detailThe Lys-Asp-Tyr Triad within the Mite Allergen Der p 1 Propeptide Is a Critical Structural Element for the pH-Dependent Initiation of the Protease Maturation.
Chevigne, Andy; Campizi, Vincenzo; Szpakowska, Martyna et al

in International Journal of Molecular Sciences (2017), 18(5),

The major house dust mite allergen, Der p 1, is a papain-like cysteine protease expressed as an inactive precursor, proDer p 1, carrying an N-terminal propeptide with a unique structure. The maturation of ... [more ▼]

The major house dust mite allergen, Der p 1, is a papain-like cysteine protease expressed as an inactive precursor, proDer p 1, carrying an N-terminal propeptide with a unique structure. The maturation of the zymogen into an enzymatically-active form of Der p 1 is a multistep autocatalytic process initiated under acidic conditions through conformational changes of the propeptide, leading to the loss of its inhibitory ability and its subsequent gradual cleavage. The aims of this study were to characterize the residues present in the Der p 1 propeptide involved in the initiation of the zymogen maturation process, but also to assess the impact of acidic pH on the propeptide structure, the activity of Der p 1 and the fate of the propeptide. Using various complementary enzymatic and structural approaches, we demonstrated that a structural triad K17p-D51p-Y19p within the N-terminal domain of the propeptide is essential for its stabilization and the sensing of pH changes. Particularly, the protonation of D51p under acidic conditions unfolds the propeptide through disruption of the K17p-D51p salt bridge, reduces its inhibition capacity and unmasks the buried residues K17p and Y19p constituting the first maturation cleavage site of the zymogen. Our results also evidenced that this triad acts in a cooperative manner with other propeptide pH-responsive elements, including residues E56p and E80p, to promote the propeptide unfolding and/or to facilitate its proteolysis. Furthermore, we showed that acidic conditions modify Der p 1 proteolytic specificity and confirmed that the formation of the first intermediate represents the limiting step of the in vitro Der p 1 maturation process. Altogether, our results provide new insights into the early events of the mechanism of proDer p 1 maturation and identify a unique structural triad acting as a stabilizing and a pH-sensing regulatory element. [less ▲]

Detailed reference viewed: 17 (2 ULg)
Full Text
Peer Reviewed
See detailAnosognosie et monitoring des souvenirs associés au « soi » dans la Maladie d’Alzheimer
Genon, Sarah ULg; Mélon, Marlène; Collette, Fabienne ULg et al

Conference (2017)

Chez les patients atteints de maladie d’Alzheimer (MA), on observe dès les stades débutants d’une part un phénomène d’anosognosie, qui peut être considéré comme une altération de la conscience de soi, et ... [more ▼]

Chez les patients atteints de maladie d’Alzheimer (MA), on observe dès les stades débutants d’une part un phénomène d’anosognosie, qui peut être considéré comme une altération de la conscience de soi, et d’autre part un dysfonctionnement des processus de monitoring mnésique [1]. En outre, l’interaction entre le soi et la mémoire (conférant un bénéfice mnésique pour les informations associées à soi), apparaît significativement altérée dans la MA. Dans la présente étude, nous avons examiné les relations entre l’anosognosie et le monitoring lors de la récupération en mémoire d’informations expérimentalement associées à soi. Nous avons évalué les processus de monitoring lors de la récupération en mémoire à l’aide d’une tâche expérimentale de 32 paires visage-prénom, ainsi que l’anosognosie à l’aide du questionnaire d’anosognosie dans la démence (AQD, [2]) chez 20 patients MA et 20 personnes âgées contrôles (AC). Durant la phase d’encodage, les paires visage-prénom ont été présentées aux participants soit comme des personnes faisant partie de leur famille (soi) soit comme des personnes faisant partie de la famille de l’expérimentateur (autrui). Ensuite, nous avons évalué les jugements de « sentiment de savoir » (FOK), les performances de rappel et de reconnaissance, ainsi que les jugements de confiance (JOC) des participants pour le nom de chaque personne lorsque son visage était présenté. Nos résultats ont confirmé l’altération de la conscience de soi (c’est-à-dire l’anosognosie mesurée par l’AQD), l’altération du bénéfice mnésique pour les informations associées à soi, ainsi que l’altération des processus de monitoring lors de la récupération en mémoire (FOK et JOC) chez les patients MA. Néanmoins, une modification de l’interaction entre le soi et les processus de monitoring chez ces patients a été observée uniquement au niveau des sentiments de confiance pour des souvenirs erronés. Nous avons également observé que l’anosognosie des troubles comportementaux était significativement corrélée à la proportion de sentiments de confiance pour des reconnaissances erronées sur les items associés à soi. En conclusion, notre étude suggère que l’altération de la conscience des troubles comportementaux chez les patients MA pourrait être liée à un déficit de monitoring des souvenirs liés à soi. C’est-à-dire que la conscience altérée du dysfonctionnement au quotidien pourrait s’appuyer sur des souvenirs personnels déformés. [less ▲]

Detailed reference viewed: 38 (0 ULg)