High-Throughput Screening of Drugs of Abuse in Urine by Supported Liquid-Liquid Extraction and UHPLC Coupled to Tandem MS

A qualitative method, involving supported liquid-liquid extraction (SLE) and ultra high pressure liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS-MS), was developed for the rapid tentative identification of various drugs of abuse in urine. In this study, 28 drugs and metabolites were covered by the screening procedure. Before analysis, urine samples were extracted by SLE and good extraction recoveries were obtained for most investigated compounds. The UHPLC strategy was then selected for the rapid separation of amphetamines, cocaine, opiates and related compounds in urine. Using columns packed with sub-2µm particles, analysis time was reduced down to 2min, while maintaining acceptable performance. Finally, the detection was by tandem MS operating in the single reaction monitoring (SRM) mode. The most intense transition was selected for the different drugs and SRM dwell times set at 5ms, to maintain sufficient data points across the narrow UHPLC peaks. The tentative identification of the drugs of interest, including amphetamines, opiates and cocaine, was based on both, retention times and mass spectrometry information. With the proposed method, limits of detection were estimated at about 1ngmL−1 and the applicability was assessed by successfully analyzing several samples of drug abusers. Finally, this study demonstrates the potential of UHPLC coupled to tandem MS for the rapid screening of drugs of abuse in urin

Metabolic processes sustaining the reviviscence of lichen Xanthoria elegans (Link) in high mountain environments.

International audienceTo survive in high mountain environments lichens must adapt themselves to alternating periods of desiccation and hydration. Respiration and photosynthesis of the foliaceous lichen, Xanthoria elegans, in the dehydrated state were below the threshold of CO2-detection by infrared gas analysis. Following hydration, respiration totally recovered within seconds and photosynthesis within minutes. In order to identify metabolic processes that may contribute to the quick and efficient reactivation of lichen physiological processes, we analysed the metabolite profile of lichen thalli step by step during hydration/dehydration cycles, using 31P- and 13C-NMR. It appeared that the recovery of respiration was prepared during dehydration by the accumulation of a reserve of gluconate 6-P (glcn-6-P) and by the preservation of nucleotide pools, whereas glycolytic and photosynthetic intermediates like glucose 6-P and ribulose 1,5-diphosphate were absent. The large pools of polyols present in both X. elegans photo- and mycobiont are likely to contribute to the protection of cell constituents like nucleotides, proteins, and membrane lipids, and to preserve the integrity of intracellular structures during desiccation. Our data indicate that glcn-6-P accumulated due to activation of the oxidative pentose phosphate pathway, in response to a need for reducing power (NADPH) during the dehydration-triggered down-regulation of cell metabolism. On the contrary, glcn-6-P was metabolised immediately after hydration, supplying respiration with substrates during the replenishment of pools of glycolytic and photosynthetic intermediates. Finally, the high net photosynthetic activity of wet X. elegans thalli at low temperature may help this alpine lichen to take advantage of brief hydration opportunities such as ice melting, thus favouring its growth in harsh high mountain climates

Pluralisme juridique et sécurisation foncière dans une commune cadastrée Le cas de Miadanandriana

Sur la base du décret du 29 août 1929 relatif au droit foncier indigène, une procédure cadastrale a été engagée sur la commune de Miadanandriana en 1935. Depuis l'établissement du plan cadastral jusqu'à l'inscription des titres cadastraux à la matrice foncière, prés de 40 ans se sont écoulés. De gros investissements en moyens humains, financiers et techniques ont été justifiés par le fait que la maîtrise du foncier constitue pour l'administration centrale un enjeu stratégique majeur de gestion des territoires et de leur développement. Aujourd'hui, l'heure est à la décentralisation de la gestion du foncier. Or à Miadanandriana, force est de constater que la gestion du foncier par les citoyens fait déjà intervenir les autorités locales notamment lors d'une recherche accrue de sécurisation foncière

Discrete spherical means of directional derivatives and Veronese maps

We describe and study geometric properties of discrete circular and spherical means of directional derivatives of functions, as well as discrete approximations of higher order differential operators. For an arbitrary dimension we present a general construction for obtaining discrete spherical means of directional derivatives. The construction is based on using the Minkowski's existence theorem and Veronese maps. Approximating the directional derivatives by appropriate finite differences allows one to obtain finite difference operators with good rotation invariance properties. In particular, we use discrete circular and spherical means to derive discrete approximations of various linear and nonlinear first- and second-order differential operators, including discrete Laplacians. A practical potential of our approach is demonstrated by considering applications to nonlinear filtering of digital images and surface curvature estimation

Perinatal Exposure to Bisphenol A Alters Early Adipogenesis in the Rat

BACKGROUND: The causes of the current obesity pandemic have not been fully elucidated. Implication of environmental endocrine disruptors such as bisphenol A (BPA) on adipose tissue development has been poorly investigated. OBJECTIVES: The aim of the present study was to evaluate the effects of perinatal exposure to BPA on early adipose storage at weaning. METHODS: Pregnant Sprague-Dawley rats had access to drinking water containing 1 mg/L BPA from day 6 of gestation through the end of lactation. Pups were weaned on postnatal day (PND) 21. At that time, we investigated perigonadal adipose tissue of pups (weight, histology, gene expression). For the remaining animals, we recorded body weight and food intake for animals on either standard chow or a high-fat diet. RESULTS: Gestational exposure to BPA did not alter the sex ratio or litter size at birth. On PND1, the weight of male and female BPA-exposed pups was increased. On PND21, body weight was increased only in females, in which parametrial white adipose tissue (pWAT) weight was increased about 3-fold. This excess of pWAT was associated with adipocyte hypertrophy and overexpression of lipogenic genes such as C/EBP-alpha (CAAT enhancer binding protein alpha), PPAR-gamma (peroxisome proliferator-activated receptor gamma), SREBP-1C (sterol regulatory element binding protein-1C), LPL (lipoprotein lipase), FAS (fatty acid synthase), and SCD-1 (stearoyl-CoA desaturase 1). In addition, gene expression of SREBP-1C, FAS, and ACC (acetyl-CoA carboxylase) was also increased in liver from BPA-exposed females at PND21, without a change in circulating lipids and glucose. After weaning, perinatal BPA exposure predisposed to overweight in a sex- and diet-dependent manner. We observed no change in food intake due to perinatal BPA exposure in rats on either standard chow or a high-fat diet. CONCLUSIONS: Perinatal exposure to a low dose of BPA increased adipogenesis in females at weaning. Adult body weight may be programmed during early life, leading to changes dependent on the sex and the nutritional status. Although further studies are required to understand the mechanisms of BPA action in early life, these results are particularly important with regard to the increasing prevalence of childhood obesity and the context-dependent action of endocrine disruptors

Risk Factors of Inadequate Colposcopy After Large Loop Excision of the Transformation Zone: A Prospective Cohort Study

International audienceObjective: The aim of the study was to identify the risk factors of post-large loop excision of the transformation zone (LLETZ) inadequate colposcopy. Materials and Methods: From December 2013 to July 2014, a total of 157 patients who had a LLETZ performed for the treatment of high-grade intraepithelial lesion with fully visible cervical squamocolumnar junction were included. All procedures were performed using semicircular loops. The use of colposcopy made during each procedure was systematically documented. Dimensions and volume of LLETZ specimens were measured at the time of procedure, before formaldehyde fixation. All participants were invited for a follow-up colposcopy 3 to 6 months after LLETZ. Primary end point was the diagnosis of post-LLETZ inadequate colposcopy, defined by a not fully visible cervical squamocolumnar junction and/or cervical stenosis. Results: Colposcopies were performed in a mean (SD) delay of 136 (88) days and were inadequate in 22 (14%) cases. Factors found to significantly increase the probability of post-LLETZ inadequate colposcopy were a history of previous excisional cervical therapy [adjusted odds ratio (aOR) = 4.29, 95% CI = 1.12-16.37, p = .033] and the thickness of the specimen (aOR = 3.12, 95% CI = 1.02-9.60, p = .047). The use of colpos-copy for the guidance of LLETZ was statistically associated with a decrease in the risk of post-LLETZ inadequate colposcopy (aOR = 0.19, 95% CI = 0.04-0.80, p = .024) as the achievement of negative endocervical margins (aOR = 0.26, 95% CI = 0.08-0.86, p = .027). Conclusions: Although the risk of post-LLETZ inadequate colpos-copy is increased in patients with history of excisional therapy and with the thickness of the excised specimen, it could be reduced with the use of colposcopic guidance and the achievement of negative endocervical margins. L arge loop excision of the transformation zone (LLETZ) is a routine procedure worldwide, because it is the first-line treatment of high-grade intraepithelial lesion (HSIL) of the cervix. Quality criteria for optimal LLETZ include the completeness of excision with the achievement of negative margins, while producing the minimal excised volume and depth of excision to minimize subsequent obstetrical and neonatal morbidity. 1,2 Obtaining negative margins is important, because incomplete excision exposes women to a significant risk of posttreatment residual and/or recurrent disease, particularly when the lesion involves the endo-cervical canal. 3,4 However, this risk remains higher to the general female population, even when negative margins are achieved. Women who had had a LLETZ remain therefore exposed to a 3-to 4-fold increased risk of developing subsequent cervical cancer at least for 20 years. 5-8 Thus, prolonged and careful post-LLETZ follow-up is mandatory, whatsoever the margins status. For the last decade, the value of human papillomavirus testing has been demonstrated in this indication. Although a negative human papillomavirus test has now been admitted as the best test of cure for patients, colposcopy remains needed when this test is found to be positive. 9-12 Although being the key examination in this indication, the accuracy of colposcopy performed after previous excisional therapy of HSIL is however questionable because the healing process might result in changes in the appearance of the transformation zone (TZ). However, the main limitation of post-LLETZ colposcopic examination is the possibility of inadequate colposcopy due to the inability to visualize the entire TZ. Known risk factors for inadequate colposcopy include age, severity of lesion, and estrogen status of the patient. 13 However, inadequate colposcopy is also one of the main adverse effects of excisional therapies of the cervix, including LLETZ. 13 However, data on the precise risk factors for inadequate colposcopy after LLETZ are limited because most studies have focused on the sole risk of cervical stenosis without considering the position and visibility of the squamocolumnar junction. 14-17 This point is however crucial because it is clinically essential to identify how post-LLETZ inadequate colposcopy could be avoided, thus preserving the possibility for the follow-up of these women

Designing and implementing a research integrity promotion plan: recommendations for research funders

Various stakeholders in science have put research integrity high on their agenda. Among them, research funders are prominently placed to foster research integrity by requiring that the organizations and individual researchers they support make an explicit commitment to research integrity. Moreover, funders need to adopt appropriate research integrity practices themselves. To facilitate this, we recommend that funders develop and implement a Research Integrity Promotion Plan (RIPP). This Consensus View offers a range of examples of how funders are already promoting research integrity, distills 6 core topics that funders should cover in a RIPP, and provides guidelines on how to develop and implement a RIPP. We believe that the 6 core topics we put forward will guide funders towards strengthening research integrity policy in their organization and guide the researchers and research organizations they fund