128 research outputs found
Structural investigation of fluorophosphate glasses by 19F, 31P MAS-​NMR and IR spectroscopy
International audienceA series of glass samples of compn. [(x)​MnF2-​(x-​80)​NaPO3-​(20)​ZnF2] where x = 0, 10, 20, 30 and 40, has been prepd. IR and NMR spectroscopy have been performed, esp. 19F MAS and 31P MAS NMR. On the basis of these measurements, glass structure may be described as a hybrid network of ZnF6 and MnF6 octahedra sharing corners and edges and also connected to tetrahedral fluorophosphate groups (PX)​4 where X = O-​ or F-​. Sodium cations fill vacancies of this network
A three-site mechanism for agonist/antagonist selective binding to vasopressin receptors
International audienc
Explaining inconsistencies between data on condom use and condom sales
BACKGROUND: Several HIV prevention programs use data on condom sales and survey-based data on condom prevalence to monitor progress. However, such indicators are not always consistent. This paper aims to explain these inconsistencies and to assess whether the number of sex acts and the number of condoms used can be estimated from survey data. This would be useful for program managers, as it would enable estimation of the number of condoms needed for different target groups. METHODS: We use data from six Demographic and Health Surveys to estimate the total annual number of sex acts and number of condoms used. Estimates of the number of sex acts are based on self-reported coital frequency, the proportion reporting intercourse the previous day, and survival methods. Estimates of the number of condoms used are based on self-reported frequency of use, the proportion reporting condom use the previous day and in last intercourse. The estimated number of condoms used is then compared with reported data on condom sales and distribution. RESULTS: Analysis of data on the annual number of condoms sold and distributed to the trade reveals very erratic patterns, which reflect stock-ups at various levels in the distribution chain. Consequently, condom sales data are a very poor indicator of the level of condom use. Estimates of both the number of sexual acts and the number of condoms used vary enormously based on the estimation method used. For several surveys, the highest estimate of the annual number of condoms used is tenfold that of the lowest estimate. CONCLUSIONS: Condom sales to the trade are a poor indicator of levels of condom use, and are therefore insufficient to monitor HIV prevention programs. While survey data on condom prevalence allow more detailed monitoring, converting such data to an estimated number of sex acts and condoms used is not straightforward. The estimation methods yield widely different results, and it is impossible to determine which method is most accurate. Until the reliability of these various estimation methods can be established, estimating the annual number of condoms used from survey data will not be feasible. Collecting survey data on the number of sex acts and the number of condoms used in a fixed time period may enable the calculation of more reliable estimates of the number of sex acts and condoms used
Conformation and dynamics of human urotensin II and urotensin related peptide in aqueous solution
Conformation
and dynamics of the vasoconstrictive peptides human
urotensin II (UII) and urotensin related peptide (URP) have been investigated
by both unrestrained and enhanced-sampling molecular-dynamics (MD)
simulations and NMR spectroscopy. These peptides are natural ligands
of the G-protein coupled urotensin II receptor (UTR) and have been
linked to mammalian pathophysiology. UII and URP cannot be characterized
by a single structure but exist as an equilibrium of two main classes
of ring conformations, <i>open</i> and <i>folded</i>, with rapidly interchanging subtypes. The <i>open</i> states
are characterized by turns of various types centered at K<sup>8</sup>Y<sup>9</sup> or F<sup>6</sup>W<sup>7</sup> predominantly with no
or only sparsely populated transannular hydrogen bonds. The <i>folded</i> conformations show multiple turns stabilized by highly
populated transannular hydrogen bonds comprising centers F<sup>6</sup>W<sup>7</sup>K<sup>8</sup> or W<sup>7</sup>K<sup>8</sup>Y<sup>9</sup>. Some of these conformations have not been characterized previously.
The equilibrium populations that are experimentally difficult to access
were estimated by replica-exchange MD simulations and validated by
comparison of experimental NMR data with chemical shifts calculated
with density-functional theory. UII exhibits approximately 72% <i>open</i>:28% <i>folded</i> conformations in aqueous
solution. URP shows very similar ring conformations as UII but differs
in an <i>open:folded</i> equilibrium shifted further toward <i>open</i> conformations (86:14) possibly arising from the absence
of folded N-terminal tail-ring interaction. The results suggest that
the different biological effects of UII and URP are not caused by
differences in ring conformations but rather by different interactions
with UTR
Associations between occupational indicators and total, work-based and leisure-time sitting: a cross-sectional study
A community effort in SARS-CoV-2 drug discovery.
peer reviewedThe COVID-19 pandemic continues to pose a substantial threat to human lives and is likely to do so for years to come. Despite the availability of vaccines, searching for efficient small-molecule drugs that are widely available, including in low- and middle-income countries, is an ongoing challenge. In this work, we report the results of an open science community effort, the "Billion molecules against Covid-19 challenge", to identify small-molecule inhibitors against SARS-CoV-2 or relevant human receptors. Participating teams used a wide variety of computational methods to screen a minimum of 1 billion virtual molecules against 6 protein targets. Overall, 31 teams participated, and they suggested a total of 639,024 molecules, which were subsequently ranked to find 'consensus compounds'. The organizing team coordinated with various contract research organizations (CROs) and collaborating institutions to synthesize and test 878 compounds for biological activity against proteases (Nsp5, Nsp3, TMPRSS2), nucleocapsid N, RdRP (only the Nsp12 domain), and (alpha) spike protein S. Overall, 27 compounds with weak inhibition/binding were experimentally identified by binding-, cleavage-, and/or viral suppression assays and are presented here. Open science approaches such as the one presented here contribute to the knowledge base of future drug discovery efforts in finding better SARS-CoV-2 treatments.R-AGR-3826 - COVID19-14715687-CovScreen (01/06/2020 - 31/01/2021) - GLAAB Enric
Inhibition des membres de la superfamille des TGF-bs (implications dans la croissance musculaire)
CAEN-BU Médecine pharmacie (141182102) / SudocLYON1-BU Santé (693882101) / SudocSudocFranceF
Etudes des relations structure-activité et pharmacomodulation de ligands sérotoninergiques
CAEN-BU Médecine pharmacie (141182102) / SudocLYON1-BU Santé (693882101) / SudocSudocFranceF
Estimation des propriétés écotoxicologiques de substances chimiques par méthodes in silico (définition de modèles globaux ou spécifiques)
CAEN-BU MĂ©decine pharmacie (141182102) / SudocSudocFranceF
Contribution à la conception du système d'information pharmaco-chimique du Centre d'Etudes et de Recherche sur le Médicament de Normandie
CAEN-BU Médecine pharmacie (141182102) / SudocLYON1-BU Santé (693882101) / SudocSudocFranceF
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