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  • Open Access English
    Authors: 
    Wera Teubner; Walter Meinl; Simone Florian; Michael Kretzschmar; Hansruedi Glatt;
    Publisher: Portland Press Ltd.

    Soluble SULTs (sulfotransferases) are important in the regulation of messenger molecules and the elimination of xenobiotics. However, sulfo-conjugation of various substrates can also lead to the formation of reactive metabolites that may induce cancer and cause other damage. The aim of the present study was to identify the SULT forms expressed in the human gastrointestinal tract, especially the colon and rectum (common sites for cancer), and to determine their cellular localization. Normal colonic or rectal tissue, resected with tumours, was obtained from 39 subjects. For comparison, we additionally studied one to four samples from stomach, jejunum, ileum, cecum and liver. SULTs were detected by immunoblotting, immunohistochemistry and measurement of enzyme activities. SULT1A1, 1A3 and 1B1 were found in all parts of the gastrointestinal tract, often exceeding levels in liver (where these forms were present at high, undetectable and low levels respectively). They were predominantly localized in differentiated enterocytes. SULT1E1 and 2A1 were only detected in liver, jejunum, ileum and cecum. SULT1C1 was readily found in stomach, but was negligible elsewhere. SULT1A2 was present at low levels in individual samples. The remaining forms were not detected with the limitation that only high levels could be recognized with the antisera used. In conclusion, SULTs are abundant in the gastrointestinal tract of man. We suspect that they are involved in the presystemic elimination of bioactive food-borne components, including aglycones released by gut microbiota, as well as the bioactivation of some procarcinogens.

  • Publication . Other literature type . Article . 2010
    Open Access English
    Authors: 
    Børge G. Nordestgaard; M. John Chapman; Kausik K. Ray; Jan Borén; Felicita Andreotti; Gerald F. Watts; Henry N. Ginsberg; Pierre Amarenco; Alberico L. Catapano; Olivier S. Descamps; +9 more
    Publisher: HAL CCSD
    Countries: Turkey, France, France, France, Netherlands, France, Croatia, Netherlands, France, France ...

    International audience; AIMS: The aims of the study were, first, to critically evaluate lipoprotein(a) [Lp(a)] as a cardiovascular risk factor and, second, to advise on screening for elevated plasma Lp(a), on desirable levels, and on therapeutic strategies. METHODS AND RESULTS: The robust and specific association between elevated Lp(a) levels and increased cardiovascular disease (CVD)/coronary heart disease (CHD) risk, together with recent genetic findings, indicates that elevated Lp(a), like elevated LDL-cholesterol, is causally related to premature CVD/CHD. The association is continuous without a threshold or dependence on LDL- or non-HDL-cholesterol levels. Mechanistically, elevated Lp(a) levels may either induce a prothrombotic/anti-fibrinolytic effect as apolipoprotein(a) resembles both plasminogen and plasmin but has no fibrinolytic activity, or may accelerate atherosclerosis because, like LDL, the Lp(a) particle is cholesterol-rich, or both. We advise that Lp(a) be measured once, using an isoform-insensitive assay, in subjects at intermediate or high CVD/CHD risk with premature CVD, familial hypercholesterolaemia, a family history of premature CVD and/or elevated Lp(a), recurrent CVD despite statin treatment, ≥3% 10-year risk of fatal CVD according to European guidelines, and/or ≥10% 10-year risk of fatal + non-fatal CHD according to US guidelines. As a secondary priority after LDL-cholesterol reduction, we recommend a desirable level for Lp(a) <80th percentile (less than ∼50 mg/dL). Treatment should primarily be niacin 1-3 g/day, as a meta-analysis of randomized, controlled intervention trials demonstrates reduced CVD by niacin treatment. In extreme cases, LDL-apheresis is efficacious in removing Lp(a). CONCLUSION: We recommend screening for elevated Lp(a) in those at intermediate or high CVD/CHD risk, a desirable level <50 mg/dL as a function of global cardiovascular risk, and use of niacin for Lp(a) and CVD/CHD risk reduction.

  • Open Access English
    Authors: 
    Raymond L. Moody; Yen-Tyng Chen; John A. Schneider; Justin Knox; Liadh Timmins; Hillary Hanson; Kangkana Koli; Mainza Durrell; Jessica Dehlin; Rebecca Eavou; +2 more
    Publisher: BioMed Central

    Abstract Background In response to COVID-19, the city of Chicago issued stay-at-home orders, which began on March 20, 2020, and restrictions meant to “flatten the curve” remained in effect until June 2, 2020. On June 3, 2020, Chicago entered the reopening phase. This study compares rates of polysubstance use by COVID-19 lockdown phase and across sociodemographic characteristics in a Chicago-based sample of Black cisgender sexual minority men (SMM) and transgender women. Method Data come from the Neighborhood and Networks (N2) cohort, an ongoing study of Black cisgender SMM and transgender women living in Chicago. Participants (N = 226) completed a survey between April 20, 2020, and July 30, 2020, during the initial peak of the COVID-19 pandemic in Chicago. We conducted chi-square tests of independence and modified Poisson regression models with robust error variance and estimated adjusted prevalence ratios. Results Alcohol and marijuana were the most used substances, with 73.5% reporting at least one drinking day and 71.2% of the sample reporting marijuana use in the past 14 days. Tobacco was used by 41.6% of the sample, and illegal drug use, which does not include marijuana, was reported by 17.7% of the sample. Substance use was consistently associated with the use of other substances. As such, polysubstance use (i.e., using two or more substances) was common in this sample (63.7%). Few sociodemographic differences emerged, and substance use was not associated with lockdown phase. Conclusion Substance use, including polysubstance use, was high in our sample of Black SMM and transgender women during the initial peak of the COVID-19 pandemic. Continued monitoring is needed given the duration of the COVID-19 pandemic and the negative health consequences associated with substance use in this population.

  • Open Access English
    Authors: 
    Joseph W. Veldman; Gerhard E. Overbeck; Daniel Negreiros; Grégory Mahy; Soizig Le Stradic; G. Wilson Fernandes; Giselda Durigan; Elise Buisson; Francis E. Putz; William J. Bond;
    Publisher: HAL CCSD
    Countries: France, Belgium

    International audience; Misperceptions about the world's grassy biomes contribute to their alarming rates of loss due to conversion for agriculture and tree plantations, as well as to forest encroachment. To illustrate the causes and consequences of these misperceptions, we show that the World Resources Institute and the International Union for Conservation of Nature misidentified 9 million square kilometers of ancient grassy biomes as providing “Opportunities” for forest restoration. Establishment of forests in these grasslands, savannas, and open-canopy woodlands would devastate biodiversity and ecosystem services. Such undesired outcomes are avoidable if the distinct ecologies and conservation needs of forest and grassy biomes become better integrated into science and policy. To start with, scientists should create maps that accurately depict grassy biomes at global and landscape scales. It is also crucial that international environmental agreements (e.g., the United Nations Framework Convention on Climate Change) formally recognize grassy biomes and their environmental values.

  • Open Access English
    Authors: 
    Peter Young; De LAJUDIE Philippe;
    Country: France

    International Committee on Systematics of Prokaryotes : Subcommittee on the Taxonomy of Rhizobia and Agrobacteria Minutes, Videoconference, , -; Minutes of the closed meeting of the ICSP Subcommittee on the Taxonomy of Rhizobia and Agrobacteria held by videoconference on 17 July 2019, and list of recent species

  • Publication . Other literature type . 2018
    French
    Authors: 
    Kowalski, Matthieu;
    Publisher: HAL CCSD
    Country: France

    Il y a bien longtemps, dans une galaxie très, très lointaine. L'ordre des GPï développe un nouvel art de résolution des problèmes inverses: la synthèse parcimonieuse. Nous présenterons ici une forme primordiale de cet art : l'algorithme de seuillage itératif combiné à n'importe quelle règle de seuillage. Allié à la parcimonie sociale, permettant une prise en compte plus perméable des structures, nous verrons comment il éclipse la parcimonie simple de type Basis Pursuit (Denoising) dans la résolution de problèmes inverses. Puis nous méditerons sur ses liens avec l'art Bayesien afin d'ériger une nouvelle forme de structure fondée sur la synthèse parcimonieuse de rang faible, permettant d'interpréter la décomposition en matrice non négative comme un nouvel a priori. Nous mesurerons également la force de ces approches sur un problème particulier: la désaturation audio. Nous illustrerons aussi les succès de ces approches sur d'autres problèmes inverses tels que la séparation de sources ou la localisation de sources M/EEG.

  • Open Access English
    Authors: 
    Mohamed Bizi; Fatima-Ezzahra El Bachra;
    Publisher: HAL CCSD
    Country: France

    International audience; The transport of carbamazepine, ciprofloxacin and sulfamethoxazole in the different pores of activated carbon in an aqueous solution is a dynamic process that is entirely dependent on the intrinsic parameters of these molecules and of the adsorbent. The macroscopic processes that take place are analyzed by interfacial diffusion and reaction models. Modeling of the experimental kinetic curves obtained following batch treatment of each solute at 2 µg/L in tap water showed (i) that the transport and sorption rates were controlled by external diffusion and intraparticle diffusion and (ii) that the effective diffusion coefficient for each solute, with the surface and pore diffusion coefficients, were linked by a linear relationship. A statistical analysis of the experimental data established correlations between the diffusional parameters and some geometrical parameters of these three molecules. Given the major discontinuities observed in the adsorption kinetics, the modeling of the experimental data required the use of traditional kinetic models, as well as a new kinetic model composed of the pseudo first or second order model and a sigmoidal expression. The predictions of this model were excellent. The solubility of each molecule below 60 °C was formulated by an empirical expression.

  • Open Access English
    Authors: 
    Sylviane Derzelle; Evelyne Turlin; Eric Duchaud; Sylvie Pagès; Frank Kunst; Alain Givaudan; Antoine Danchin;
    Publisher: HAL CCSD
    Country: France

    ABSTRACT Photorhabdus luminescens is a symbiont of entomopathogenic nematodes. Analysis of the genome sequence of this organism revealed a homologue of PhoP-PhoQ, a two-component system associated with virulence in intracellular bacterial pathogens. This organism was shown to respond to the availability of environmental magnesium. A mutant with a knockout mutation in the regulatory component of this system ( phoP ) had no obvious growth defect. It was, however, more motile and more sensitive to antimicrobial peptides than its wild-type parent. Remarkably, the mutation eliminated virulence in an insect model. No insect mortality was observed after injection of a large number of the phoP bacteria, while very small amounts of parental cells killed insect larvae in less than 48 h. At the molecular level, the PhoPQ system mediated Mg 2+ -dependent modifications in lipopolysaccharides and controlled a locus ( pbgPE ) required for incorporation of 4-aminoarabinose into lipid A. Mg 2+ -regulated gene expression of pbgP1 was absent in the mutant and was restored when phoPQ was complemented in trans . This finding highlights the essential role played by PhoPQ in the virulence of an entomopathogen.

  • Open Access English
    Authors: 
    E. Blas; L Falcao; Thierry Gidenne; C Scapinello; Victor Pinheiro; A. I. García; Rosa Carabaño;
    Publisher: HAL CCSD
    Countries: Spain, France, France

    [EN] In four laboratories, a total of 52 adult rabbits were fitted with a single T glass cannula at terminal ileum. After surgery recovery, animals were fed ad libitum with the same batch of a diet labelled by the addition of ytterbium attached to fibre particles. The effect of time during the ileal digesta collection period (morning and evening) on ileal digesta composition and ileal digestibility of DM, CP, NDF and ADF was evaluated. Compared with the evening samples, the morning samples had higher content of ytterbium (+5%) and CP (+43%) but lower contents of NDF (-9%) and ADF (-11%). Consequently, ileal digestibility for DM, NDF and ADF resulted in higher figures when calculated from the morning samples as opposed to those from the evening samples. However, CP ileal digestibility results were just the opposite. When compared with the results obtained as a reference value from the 24-hour samples (a pool of collections obtained in the morning, evening and night), the data average from the morning and the evening samples did not differ significantly. Therefore, it is possible to reduce the number of collections and simplify ileal digesta sampling by avoiding night collections. This study was partially supported by the European Commission (Concerted Action FAIR3-PL1651)

  • Open Access English
    Authors: 
    Léandre Gagné Lemieux; Martin Simoneau; Jean Francois Tessier; Maxime Billot; Jean Blouin; Normand Teasdale;
    Publisher: HAL CCSD
    Country: France
    Project: NSERC

    When tracing a template with mirror-reversed vision (or distorted vision), the sensory information arising from the movement does not match the expected sensory consequences. In such situations, participants have to learn a new visuomotor mapping in order to trace the template with an accuracy and speed approaching that observed when tracing with direct vision. There are several suggestions that such visuomotor learning requires lowering the gain of the proprioceptive inputs. Generally, subjects learn this task in a seated condition offering a stable postural platform. Adapting to the new visuomotor relationship in a standing condition could add complexity and even hinder sensorimotor adaptation because balance control and processing of additional information typically interfere with each other. To examine this possibility, older individuals and young adults (on average, 70 and 22 years of age, respectively) were assigned to groups that trained to trace a shape with mirror-reversed vision in a seated or a standing condition for two sessions. For a third session, the seated groups (young and elderly) transferred to the standing condition while the standing groups continued to perform the tracing task while standing. This procedure allowed comparing the tracing performance of all groups (with the same amount of practice) in a standing condition. The standing groups also did a fourth session in a seated condition. Results show that older participants initially exposed to the standing condition were much slower to trace the template than all other groups (including the older group that performed the tracing task while seated). This slowness did not result from a baseline general slowness but from a genuine interference between balance control and the visuomotor conflict resulting from tracing the pattern with mirror-reversed vision. Besides, the Standing-Old participants that transferred to a seated condition in the fourth session immediately improved their tracing by reducing the total displacement covered by the pen to trace the template. Interestingly, the results did not support a transfer-appropriate practice hypothesis which suggests that training in a standing condition (at the third session) should have benefited the performance of those individuals who initially learned to trace the mirror pattern in a standing condition. This has important clinical implications: training at adapting to new sensory contexts or environmental conditions in conditions that do not challenge balance control could be necessary if one desires to attenuate the detrimental consequences on the postural or motor performances brought up by the interference between maintaining balance and the sensory reweighing processes.

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