Gestion des hypoglycémies après le bypass gastrique [Management of hyperinsulinemic hypoglycemia post-gastric bypass surgery].

Gastric bypass surgery is an effective treatment for morbid obesity, allowing a substantial weight loss together with an improvement of the cardiovascular and metabolic comorbidities, particularly the glucose control. However, after gastric bypassing, an imbalance between sensitivity and insulin secretion may be observed. This disorder gives rise to hyperinsulinemic hypoglycemia (late dumping syndrome) and is characterized by a dizziness that can be disabling. This problem must be distinguished from conditions provoking similar symptoms, as for instance the early dumping syndrome and the food restriction-related hypoglycemia. Since all these conditions need a particular management, their distinction is essential.

Correlating the end-Triassic mass extinction and flood basalt volcanism at the 100 ka level

New high-precision U/Pb geochronology from volcanic ashes shows that the Triassic-Jurassic boundary and end-Triassic biological crisis from two independent marine stratigraphic sections correlate with the onset of terrestrial flood volcanism in the Central Atlantic Magmatic Province to <150 ka. This narrows the correlation between volcanism and mass extinction by an order of magnitude for any such catastrophe in Earth history. We also show that a concomitant drop and rise in sea level and negative delta C-13 spike in the very latest Triassic occurred locally in <290 ka. Such rapid sea-level fluctuations on a global scale require that global cooling and glaciation were closely associated with the end-Triassic extinction and potentially driven by Central Atlantic Magmatic Province volcanism.

Post-genomic update on a classical candidate gene for coronary artery disease: ESR1.

BACKGROUND: After age, sex is the most important risk factor for coronary artery disease (CAD). The mechanism through which women are protected from CAD is still largely unknown, but the observed sex difference suggests the involvement of the reproductive steroid hormone signaling system. Genetic association studies of the gene-encoding Estrogen Receptor α (ESR1) have shown conflicting results, although only a limited range of variation in the gene has been investigated. METHODS AND RESULTS: We exploited information made available by advanced new methods and resources in complex disease genetics to revisit the question of ESR1's role in risk of CAD. We performed a meta-analysis of 14 genome-wide association studies (CARDIoGRAM discovery analysis, N=≈87,000) to search for population-wide and sex-specific associations between CAD risk and common genetic variants throughout the coding, noncoding, and flanking regions of ESR1. In addition to samples from the MIGen (N=≈6000), WTCCC (N=≈7400), and Framingham (N=≈3700) studies, we extended this search to a larger number of common and uncommon variants by imputation into a panel of haplotypes constructed using data from the 1000 Genomes Project. Despite the widespread expression of ERα in vascular tissues, we found no evidence for involvement of common or low-frequency genetic variation throughout the ESR1 gene in modifying risk of CAD, either in the general population or as a function of sex. CONCLUSIONS: We suggest that future research on the genetic basis of sex-related differences in CAD risk should initially prioritize other genes in the reproductive steroid hormone biosynthesis system.

Learning collaboration in General Internal Medicine: a pilot project for undergraduate students in nursing, physiotherapy and medicine

Background: A form of education called Interprofessional Education (IPE) occurs when two or more professions learn with, from and about each other. The purpose of IPE is to improve collaboration and the quality of care. Today, IPE is considered as a key educational approach for students in the health professions. IPE is highly effective when delivered in active patient care, such as in clinical placements. General internal medicine (GIM) is a core discipline where hospital-based clinical placements are mandatory for students in many health professions. However, few interprofessional (IP) clinical placements in GIM have been implemented. We designed such a placement. Placement design: The placement took place in the Department of Internal Medicine at the CHUV. It involved students from nursing, physiotherapy and medicine. The students were in their last year before graduation. Students formed teams consisting of one student from each profession. Each team worked in the same unit and had to take care of the same patient. The placement lasted three weeks. It included formal IP sessions, the most important being facilitated discussions or "briefings" (3x/w) during which the students discussed patient care and management. Four teams of students eventually took part in this project. Method: We performed a type of evaluation research called formative evaluation. This aimed at (1) understanding the educational experience and (2) assessing the impact of the placement on student learning. We collected quantitative data with pre-post clerkship questionnaires. We also collected qualitative data with two Focus Groups (FG) discussions at the end of the placement. The FG were audiotaped and transcribed. A thematic analysis was then performed. Results: We focused on the qualitative data, since the quantitative data lacked of statistical power due to the small numbers of students (N = 11). Five themes emerged from the FG analysis: (1) Learning of others' roles, (2) Learning collaborative competences, (3) Striking a balance between acquiring one's own professional competences and interprofessional competences, (4) Barriers to apply learnt IP competences in the future and (5) Advantages and disadvantages of IP briefings. Conclusions: Our IP clinical placement in GIM appeared to help students learn other professionals' roles and collaborative skills. Some challenges (e.g. finding the same patient for each team) were identified and will require adjustments.

Decoupled post-glacial history in mutualistic plant-insect interactions: insights from the yellow loosestrife (Lysimachia vulgaris) and its associated oil-collecting bees (Macropis europaea and M-fulvipes)

AimWe take a comparative phylogeographical approach to assess whether three species involved in a specialized oil-rewarding pollination system (i.e. Lysimachia vulgaris and two oil-collecting bees within the genus Macropis) show congruent phylogeographical trajectories during post-glacial colonization processes. Our working hypothesis is that within specialized mutualistic interactions, where each species relies on the co-occurrence of the other for survival and/or reproduction, partners are expected to show congruent evolutionary trajectories, because they are likely to have followed parallel migration routes and to have shared glacial refugia. LocationWestern Palaearctic. MethodsOur analysis relies on the extensive sampling of 104 Western Palaearctic populations (totalling 434, 159 and 74 specimens of Lysimachiavulgaris, Macropiseuropaea and Macropisfulvipes, respectively), genotyped with amplified fragment length polymorphism. Based on this, we evaluated the regional genetic diversity (Shannon diversity and allele rarity index) and genetic structure (assessed using structure, population networks, isolation-by-distance and spatial autocorrelation metrics) of each species. Finally, we compared the general phylogeographical patterns obtained. ResultsContrary to our expectations, the analyses revealed phylogeographical signals suggesting that the investigated organisms demonstrate independent post-glacial trajectories as well as distinct contemporaneous demographic parameters, despite their mutualistic interaction. Main conclusionsThe mutualistic partners investigated here are likely to be experiencing distinct and independent evolutionary dynamics because of their contrasting life-history traits (e.g. dispersal abilities), as well as distinct hubs and migration routes. Such conditions would prevent and/or erase any signature of co-structuring of lineages in space and time. As a result, the lack of phylogeographical congruence driven by differences in life-history traits might have arisen irrespective of the three species having shared similar Pleistocene glacial refugia.

La diversité des motivations des employés publics : recherche exploratoire dans un contexte post-bureaucratique en Suisse

Durant les dernières décennies, la recherche portant sur la motivation des fonctionnaires a été dominée par deux courants théoriques : l'approche dite des choix rationnels, et celle portant sur la motivation au service public. Dans l'environnement post-bureaucratique actuel, cette vision simplifiée, qui reflète aussi dans une certaine mesure la dichotomie « public-privé », ne reflète plus de manière adéquate la complexité et l'hétérogénéité des motivations des agents publics. Basée sur des données empiriques qualitatives et quantitatives, une typologie originale des motivations dans l'univers post-bureaucratique est développée et testée dans plusieurs organisations publiques suisses. Elle révèle des facteurs de motivations qui combinent de manière originale des éléments classiques de la bureaucratie avec d'autres sources de motivation caractéristiques de formes modernes d'administration publique.

Moderate exercise blunts oxidative stress induced by normobaric hypoxic confinement

PURPOSE: Both acute hypoxia and physical exercise are known to increase oxidative stress. This randomized prospective trial investigated whether the addition of moderate exercise can alter oxidative stress induced by continuous hypoxic exposure. METHODS: Fourteen male participants were confined to 10-d continuous normobaric hypoxia (FIO2 = 0.139 +/- 0.003, PIO2 = 88.2 +/- 0.6 mm Hg, approximately 4000-m simulated altitude) either with (HCE, n = 8, two training sessions per day at 50% of hypoxic maximal aerobic power) or without exercise (HCS, n = 6). Plasma levels of oxidative stress markers (advanced oxidation protein products [AOPP], nitrotyrosine, and malondialdehyde), antioxidant markers (ferric-reducing antioxidant power, superoxide dismutase, glutathione peroxidase, and catalase), nitric oxide end-products, and erythropoietin were measured before the exposure (Pre), after the first 24 h of exposure (D1), after the exposure (Post) and after the 24-h reoxygenation (Post + 1). In addition, graded exercise test in hypoxia was performed before and after the protocol. RESULTS: Maximal aerobic power increased after the protocol in HCE only (+6.8%, P < 0.05). Compared with baseline, AOPP was higher at Post + 1 (+28%, P < 0.05) and nitrotyrosine at Post (+81%, P < 0.05) in HCS only. Superoxide dismutase (+30%, P < 0.05) and catalase (+53%, P < 0.05) increased at Post in HCE only. Higher levels of ferric-reducing antioxidant power (+41%, P < 0.05) at Post and lower levels of AOPP (-47%, P < 0.01) at Post + 1 were measured in HCE versus HCS. Glutathione peroxidase (+31%, P < 0.01) increased in both groups at Post + 1. Similar erythropoietin kinetics was noted in both groups with an increase at D1 (+143%, P < 0.01), a return to baseline at Post, and a decrease at Post + 1 (-56%, P < 0.05). CONCLUSIONS: These data provide evidence that 2 h of moderate daily exercise training can attenuate the oxidative stress induced by continuous hypoxic exposure.

Techniques for CT and MR, post-processing, radiation

Brain perfusion can be assessed by CT and MR. For CT, two major techniques are used. First, Xenon CT is an equilibrium technique based on a freely diffusible tracer. First pass of iodinated contrast injected intravenously is a second method, more widely available. Both methods are proven to be robust and quantitative, thanks to the linear relationship between contrast concentration and x-ray attenuation. For the CT methods, concern regarding x-ray doses delivered to the patients need to be addressed. MR is also able to assess brain perfusion using the first pass of gadolinium based contrast agent injected intravenously. This method has to be considered as a semi-quantitative because of the non linear relationship between contrast concentration and MR signal changes. Arterial spin labeling is another MR method assessing brain perfusion without injection of contrast. In such case, the blood flow in the carotids is magnetically labelled by an external radiofrequency pulse and observed during its first pass through the brain. Each of this various CT and MR techniques have advantages and limits that will be illustrated and summarized.Learning Objectives:1. To understand and compare the different techniques for brain perfusion imaging.2. To learn about the methods of acquisition and post-processing of brain perfusion by first pass of contrast agent for CT and MR.3. To learn about non contrast MR methods (arterial spin labelling).

Individualiser la thérapie d'exposition pour le stress post-traumatique: le cas de Caroline

Dans la thérapie de l'état de stress post-traumatique chronique (PTSD), l'Exposition Prolongée (PE) à des stimuli associes à une expérience d'origine traumatique est considérée comme une méthode de traitement de pointe. Notre étude de cas, basée sur l'utilisation du manuel de Foa et Rothbaum (1998), concerne Caroline, une patiente adulte victime d'abus sexuels dans l'enfance, traitée en 40 séances, sur une durée d'une année. En complément, nous avons la technique de l'«Analyse des Plans» de Caspar (1995, 2007) pour la formulation de cas individualisée et la planification du traitement, selon le concept de Caspar de la Relation Thérapeutique Orientée sur les Motifs (MOTR). Le traitement a été très efficace, comme l'attestent les mesures quantitatives standardisées, les changements dans les schémas de comportements, ainsi que son compte rendu subjectif. Une analyse du processus thérapeutique illustre l'importance d'une combinaison de procédures basées sur un manuel avec des formulations et interventions de cas individuels. Le cas est discute dans le contexte de l'amélioration du traitement cognitivo-comportemental du PTSD.

Management of a post-operative multi-resistant infectious spondylitis associated with a kyphotic deformity.

Anterior spinal infection (prevertebral abscess and/or discitis) after posterior instrumentation for vertebral fractures is a challenging complication, since a new implant may become necessary anteriorly, in a septic environment. Generally accepted management guidelines are yet to be established. The authors present a case of posterior instrumentation for fractures of T12 and L1, complicated after 9 months with an anterior infection (prevertebral abscess and discitis) with extended-spectrum beta-lactamase (ESBL) producing Escherichia coli (E. coli). This case is unique in that the multi-resistant organism was isolated only after the second stage of infection treatment, which consisted of anterior débridement and anterior implantation of titanium cages and rods. In this particular case, infection was controlled despite implantation of multiple cages, screws and rods, and fusion was achieved, by means of intravenous antibiotic treatment for 12 months. At the latest follow-up, 24 months post surgery, there was no evidence of infection. This problem case may be helpful for surgeons confronted with spinal deformities secondary to infections with multi-resistant organisms.

Bentho-planktonic evidence from the Austrian Alps for a decline in sea-surface carbonate production at the end of the Triassic

A high-resolution micropalaeontological study, combined with geochemical and sedimentological analyses was performed on the Tiefengraben, Schlossgraben and Eiberg sections (Austrian Alps) in order to characterize sea-surface carbonate production during the end-Triassic crisis. At the end-Rhaetian, the dominant calcareous nannofossil Prinsiosphaera triassica shows a decrease in abundance and size and this is correlated with a increase in delta O-18 and a gradual decline in delta C-13(carb) values. Simultaneously, benthic foraminiferal assemblages show a decrease in diversity and abundance of calcareous taxa and a dominance of infaunal agglutinated taxa. The smaller size of calcareous nannofossils disturbed the vertical export balance of the biological carbon pump towards the sea-bottom, resulting in changes in feeding strategies within the benthic foraminiferal assemblages from deposit feeders to detritus feeders and bacterial scavengers. These micropalaeontological data combined with geochemical proxies suggest that changes in seawater chemistry and/or cooling episodes might have occurred in the latest Triassic, leading to a marked decrease of carbonate production. This in turn culminated in the quasi-absence of calcareous nannofossils and benthic foraminifers in the latest Triassic. The aftermath (latest Triassic earliest Jurassic) was characterised by abundance peaks of ``disaster'' epifaunal agglutinated foraminifera Trochammina on the sea-floor. Central Atlantic Magmatic Province (CAMP) paroxysmal activity, superimposed on a major worldwide regressive phase, is assumed to be responsible for a deterioration in marine palaeoenvironments. CAMP sulfuric emissions might have been the trigger for cooling episodes and seawater acidification leading to disturbance of the surface carbonate production at the very end-Triassic.