1,174 research outputs found
La recherche juridique sur les prélèvements biologiques réalisés dans le cadre des autopsies et objets de scellés judiciaires. Nécessité d'une adaptation législative
Currently, it is legally impossible to conduct scientific research on tissue and organ samples taken from forensic autopsies. In fact, the law schedules the destruction of such samples at the end of the judicial investigation, and the common law rules governing cadaver research cannot be applied to the forensic context. However, nothing seems in itself to stand in the way of such research since, despite their specific nature, these samples from forensic autopsies could be subject, following legislative amendments, to common law relating to medical research on samples taken from deceased persons. But an essential legislative amendment will have the goal firstly to allow the Biomedicine Agency to become authorized to issue a research permit and secondly, to change the research conditions in terms of the non-opposition of the deceased to the said research. Such an amendment would be a true breakthrough because it would allow teams to continue to move forward calmly in research, and allow this research to be placed within a legal framework, which would promote international exchanges
Efficacy and safety of alirocumab in insulin-treated patients with type 1 or type 2 diabetes and high cardiovascular risk:Rationale and design of the ODYSSEY DM-INSULIN trial
Aims: The coadministration of alirocumab, a PCSK9 inhibitor for treatment of hypercholesterolaemia, and insulin in diabetes mellitus (DM) requires further study. Described here is the rationale behind a phase-IIIb study designed to characterize the efficacy and safety of alirocumab in insulin-treated patients with type 1 (T1) or type 2 (T2) DM with hypercholesterolaemia and high cardiovascular (CV) risk. Methods: ODYSSEY DM-INSULIN (NCT02585778) is a randomized, double-blind, placebo-controlled, multicentre study that planned to enrol around 400 T2 and up to 100 T1 insulin-treated DM patients. Participants had low-density lipoprotein cholesterol (LDL-C) levels at screening. ≥. 70. mg/dL (1.81. mmol/L) with stable maximum tolerated statin therapy or were statin-intolerant, and taking (or not) other lipid-lowering therapy; they also had established CV disease or at least one additional CV risk factor. Eligible patients were randomized 2:1 to 24. weeks of alirocumab 75. mg every 2. weeks (Q2W) or a placebo. Alirocumab-treated patients with LDL-C. ≥. 70. mg/dL at week 8 underwent a blinded dose increase to 150. mg Q2W at week 12. Primary endpoints were the difference between treatment arms in percentage change of calculated LDL-C from baseline to week 24, and alirocumab safety. Results: This is an ongoing clinical trial, with 76 T1 and 441 T2 DM patients enrolled; results are expected in mid-2017. Conclusion: The ODYSSEY DM-INSULIN study will provide information on the efficacy and safety of alirocumab in insulin-treated individuals with T1 or T2 DM who are at high CV risk and have hypercholesterolaemia not adequately controlled by the maximum tolerated statin therapy
Low Temperature Plasma Synthesis of Nanocrystals and their Application to the Growth of Crystalline Silicon and Germanium Thin Films
International audienceWe summarize our research studies on the synthesis of silicon and germanium nanocrystals and their application to the growth of a variety of thin films, spanning the range from fully disordered amorphous up to fully ordered crystalline. All these films are deposited in a standard radio-frequency glow discharge system at low temperature (~200 °C). We show how the plasma synthesis of silicon nanocrystals, initially a side effect of powder formation, has become over the years an exciting field of research which has opened the way to new opportunities in the field of materials deposition and their application to optoelectronic devices. Our results suggest that epitaxy requires the melting/amorphization of the nanocrystals upon impact on the substrate, the subsequent epitaxial growth being favored on (100) c-Si substrates. As a consequence, the control of the impact energy is a critical aspect of the growth which will require new strategies such as the use of tailored voltage waveforms
A potassium tert-butoxide and hydrosilane system for ultra-deep desulfurization of fuels
Hydrodesulfurization (HDS) is the process by which sulfur-containing impurities are removed from petroleum streams, typically using a heterogeneous, sulfided transition metal catalyst under high H_2 pressures and temperatures. Although generally effective, a major obstacle that remains is the desulfurization of highly refractory sulfur-containing heterocycles, such as 4,6-dimethyldibenzothiophene (4,6-Me_2DBT), which are naturally occurring in fossil fuels. Homogeneous HDS strategies using well-defined molecular catalysts have been designed to target these recalcitrant S-heterocycles; however, the formation of stable transition metal sulfide complexes following C–S bond activation has largely prevented catalytic turnover. Here we show that a robust potassium (K) alkoxide (O)/hydrosilane (Si)-based (‘KOSi’) system efficiently desulfurizes refractory sulfur heterocycles. Subjecting sulfur-rich diesel (that is, [S] ∼ 10,000 ppm) to KOSi conditions results in a fuel with [S] ∼ 2 ppm, surpassing ambitious future governmental regulatory goals set for fuel sulfur content in all countries.
Fossil fuels contain naturally occurring organosulfur impurities, with quantities varying depending on the type of feedstock. These sulfur-containing organic small molecules poison catalytic converters and generate polluting sulfur dioxides when combusted. Hydrodesulfurization (HDS) is the industrial process by which sulfur impurities are removed from petroleum fractions prior to their use as fuels. Currently, HDS is performed by treating petroleum with H_2 at high pressures and temperatures (that is, 150–2,250 psi and 400 °C) over heterogeneous catalysts such as cobalt-doped molybdenum sulfide supported on alumina (that is, CoMoS_x∕γ-Al_2O_3; Fig. 1a). However, certain organosulfur species, in particular dibenzothiophenes alkylated at positions 4 and 6, are not efficiently removed. Homogeneous strategies employing sophisticated, well-defined transition metal complexes—including those based on platinum, nickel, tungsten, molybdenum, palladium, ruthenium, rhodium, iron, cobalt, and others—have been extensively investigated. While these studies have provided valuable mechanistic insights, several fundamental issues, such as the formation of stable organometallic S–M species upon C–S bond activation by the metal centre (Fig. 1b), generally restrict industrial implementation of such methods. Rare examples of desulfurization of dibenzothiophenes alkylated at the 4 and 6 positions by homogeneous transition metal catalysis utilized either Ni compounds in combination with superstoichiometric alkyl Grignard reagents or Ni or Co phosphoranimide complexes in the presence of superstoichiometric KH. These issues pose a formidable challenge for the development of new HDS methods. Moreover, increasingly strict governmental regulations require limiting the sulfur content in diesel fuel and gasoline (in the US: typically <15 and <30 ppm, respectively) as well as other fuels, rendering the development of new powerful HDS methods a primary global concern.
In 2013, Grubbs and co-workers reported the KO^tBu mediated cleavage of aryl C–O bonds in lignin models in the absence of transition metals using hydrosilanes. Careful inductively coupled plasma mass spectrometry (ICP-MS) analyses of the reagents and reaction mixtures ruled out catalysis with transition metals. We thus became interested in extending this method to sulfur heterocycles of relevance in oil and gas refining applications. Herein, we report that the robust KOtBu/silane-based (that is, KOSi) system is a powerful and effective homogeneous HDS method, which desulfurizes HDS-resistant dibenzothiophenes in good yield and reduces the sulfur content in diesel fuel to remarkably low levels (Fig. 1c)
Photovaporisation prostatique au laser chez les patients à haut risque hémorragique
Introduction: Les patients sous traitement anticoagulant sont à risque élevé de saignement lors de la résection transurétrale de la prostate ou del'adénomectomie par taille vésicale et ils se voient souvent récuser pour la chirurgie de l'hyperplasie bénigne de la prostate symptomatique. En Utilisant la photovaporisation de la prostate, les patients à haut risque peuvent subir en toute sécurité la chirurgie. Nous avons évalué l'innocuité et l'efficacité de la photovaporisation de la prostate (PVP) chez les patients sous anticoagulants en cours avec les dérivés de la coumarine, l'aspirineou le clopidogrel, se plaignant de symptômes d'hypertrophie bénigne de la prostate.Méthodes: Entre janvier 2009 et mai 2010, 47 hommes sous anticoagulation systémique ont subi une photovaporisation de la prostate. Les données ont été recueillies sur les caractéristiques démographiques,les comorbidités, les complications, la natrémie, l'hémoglobine, le débit urinaire maximal, le résidu post-mictionnel, l'IPSS et les complications.Résultats: L'âge moyen était de 78 ans, le volume prostatique moyen était de 44g et le PSA était de 3.4ng/ml. Parmi les 10 patients (21.2%)étaient sous AVK, 27 (57.4%) étaient sous aspirine, 2 (4.2%) étaient sous clopidogrel, un sous fondaparinux et 6 (12.7%) étaient sous 2 anticoagulants ou plus. Le score ASA moyen était de 3. La durée moyenne de fonctionnement de l'appareil était de 38 minutes, l'énergie moyenneutilisée était de 200kJ. La durée moyenne d'hospitalisation était de 2 jours. Les complications survenant dans les 30 jours comprenaient uneinfection urinaire chez 5 patients (10.6%), une dysurie chez 4 patients et une hémorragie retardée chez 4 autres (8.5%). Un seul de ces patients anécessité une transfusion sanguine et aucun patient n'a nécessité une réintervention. En 3 mois de suivi un seul patient a nécessité une incision du col vésical pour sclérose du col. Aucune incontinence ou sténose urétrale n'a été rapportée. Des améliorations significatives ont été notées dans l'IPSS, le débit urinaire maximal et le résidu post-mictionnel. Conclusion: La PVP est caractérisé par d'excellentes propriétés hémostatiques et taux très faible de complications peropératoires même chez les patients sous 2 ou plusieurs agents anticoagulants. Sur la base de nos résultats péri-opératoires, nous recommandons la PVP comme traitement chirurgical de première intention chez les patients à haut risque de hémorragique souffrant de symptômes d'hypertrophie bénigne de la prostate
Comparison of 3D turbulence measurements using three staring wind lidars and a sonic anemometer
Temporal changes in frequency of severe hypoglycemia treated by emergency medical services in types 1 and 2 diabetes:a population-based data-linkage cohort study
Background Almost 20 years ago, the frequencies of severe hypoglycemia requiring emergency medical treatment were reported in people with types 1 and 2 diabetes in the Tayside region of Scotland. With subsequent improvements in the treatment of diabetes, concurrent with changes in the provision of emergency medical care, a decline in the frequency of severe hypoglycemia could be anticipated. The present population-based data-linkage cohort study aimed to ascertain whether a temporal change has occurred in the incidence rates of hypoglycemia requiring emergency medical services in people with types 1 and 2 diabetes. Methods The study population comprised all people with diabetes in Tayside, Scotland over the period 1 January 2011 to 31 December 2012. Patients’ data from different healthcare sources were linked anonymously to measure the incidence rates of hypoglycemia requiring emergency medical services that include treatment by ambulance staff and in hospital emergency departments, and necessitated hospital admission. These were compared with data recorded in 1997–1998 in the same region. Results In January 2011 to December 2012, 2029 people in Tayside had type 1 diabetes and 21,734 had type 2 diabetes, compared to 977 and 7678, respectively, in June 1997 to May 1998. In people with type 2 diabetes, the proportion treated with sulfonylureas had declined from 36.8 to 22.4% (p<0.001), while insulin-treatment had increased from 11.7 to 18.7% (p<0.001). The incidence rate of hypoglycemia requiring emergency medical treatment had significantly fallen from 0.115 (95% CI: 0.094–0.136) to 0.082 (0.073–0.092) events per person per year in type 1 diabetes (p<0.001), and from 0.118 (0.095–0.141) to 0.037 (0.003–0.041) in insulin-treated type 2 diabetes (p=0.008). However, the absolute annual number of hypoglycemia events requiring emergency treatment was 1.4-fold higher. Conclusions Although from 1998 to 2012 the incidences of hypoglycemia requiring emergency medical services appeared to have declined by a third in type 1 diabetes and by two thirds in insulin-treated type 2 diabetes, because the prevalence of diabetes was higher (2.7 fold), the number of severe hypoglycemia events requiring emergency medical treatment was greater
Less invasive methods of advanced hemodynamic monitoring: principles, devices, and their role in the perioperative hemodynamic optimization.
The monitoring of the cardiac output (CO) and other hemodynamic parameters, traditionally performed with the thermodilution method via a pulmonary artery catheter (PAC), is now increasingly done with the aid of less invasive and much easier to use devices. When used within the context of a hemodynamic optimization protocol, they can positively influence the outcome in both surgical and non-surgical patient populations. While these monitoring tools have simplified the hemodynamic calculations, they are subject to limitations and can lead to erroneous results if not used properly. In this article we will review the commercially available minimally invasive CO monitoring devices, explore their technical characteristics and describe the limitations that should be taken into consideration when clinical decisions are made
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The ocean sampling day consortium.
Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world's oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits
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