316 research outputs found
Incidence et prise en charge des hypoglycémies sévÚres ayant motivé un appel au centre 15 de Nice
Introduction: De grandes Ă©tudes ont mis en Ă©vidence la responsabilitĂ© des hypoglycĂ©mies sĂ©vĂšres, dĂ©finies par la nĂ©cessitĂ© de recours Ă un tiers pour le resucrage, dans lâaugmentation des risques cardio-vasculaires et de la mortalitĂ©. Leur incidence, modalitĂ©s de prise en charge et coĂ»ts engendrĂ©s sont mal connus.<br>Patients et MĂ©thode: Etude prospective observationnelle incluant les hypoglycĂ©mies sĂ©vĂšres aprĂšs appel au centre 15 de Nice pour la pĂ©riode de mai 2013 Ă avril 2014. <br>RĂ©sultats: Population de 33 875 patients diabĂ©tiques, 195 hypoglycĂ©mies sĂ©vĂšres soit 0,58 hypoglycĂ©mies sĂ©vĂšres/100 patients/an. CaractĂ©ristiques des patients : Ăąge moyen: 61,8ans ± 21,4 ; homme: 58% ; anciennetĂ© du diabĂšte >10ans : (67,5%) ; antĂ©cĂ©dent dâhypoglycĂ©mie sĂ©vĂšre au cours des douze derniers mois: 57,9%. Traitements impliquĂ©s : insulinothĂ©rapie 88,3% dont 10,2% combinĂ©e avec un antidiabĂ©tique oral. Le repaglinide retrouvĂ© dans 41,2% (Ăąge moyen : 81,1 ans ± 21,4), et le glibenclamide 29,4% (Ăąge moyen : 77,3 ans ± 21,4). Circonstances : 82,1% au domicile; 24,6% nocturnes. Avant lâarrivĂ©e des secours : glycĂ©mie relevĂ©e pour 29,2%. Moyenne Ă leur arrivĂ©e : 0,42 g/l ± 0.29. Resucrage: per os 44,1%, intraveineux perfusion 42% et injection directe 34,9%. 14,9% Ă©taient hospitalisĂ©s et 22% transfĂ©rĂ©s aux urgences. Le coĂ»t total Ă©tait de 352 138âŹ.<br>Conclusion: Cette Ă©tude permet de caractĂ©riser les hypoglycĂ©mies sĂ©vĂšres, la prise en charge ainsi que le coĂ»t, extrapolĂ© au niveau national, estimĂ© Ă 35 millions dâeuros (0,2% du coĂ»t du diabĂšte). La mise en place de protocoles de soins, de mesures Ă©ducatives et des rĂ©Ă©valuations thĂ©rapeutiques sont Ă entreprendre pour rĂ©duire ce risque
Perirenal Fluid Collection after Kidney Transplantation
A 30-year-old male presented with pitting edema. He had received a kidney transplantation 3 months previously. His serum creatinine level was increased, and a renal ultrasound showed hypoechoic fluid collection in the perirenal space and pelvic cavity. We conducted sono-guided percutaneous drainage of the fluid collected in the pelvic cavity. The chemistry of the peritoneal fluid was more equivalent to serum chemistry values than to urinary values. Simple aspiration and treatment with antibiotics were performed. We have presented a case of lymphocele after kidney transplantation. This case suggests that physicians should remember how to differentiate the pelvic cavity fluid collection in patients who have received a kidney transplant
Dynamic Nuclear Polarization NMR Spectroscopy Allows High-Throughput Characterization of Microporous Organic Polymers
Dynamic nuclear polarization (DNP) solid-state NMR was used to obtain natural abundance 13C and 15N CP MAS NMR spectra of microporous organic polymers with excellent signal-to-noise ratio, allowing for unprecedented details in the molecular structure to be determined for these complex polymer networks. Sensitivity enhancements larger than 10 were obtained with bis-nitroxide radical at 14.1 T and low temperature (âŒ105 K). This DNP MAS NMR approach allows efficient, high-throughput characterization of libraries of porous polymers prepared by combinatorial chemistry methods
Mesoporous Silica Nanoparticles Loaded with Surfactant: Low Temperature Magic Angle Spinning 13C and 29Si NMR Enhanced by Dynamic Nuclear Polarization
We show that dynamic nuclear polarization (DNP) can be used to enhance NMR signals of13C and 29Si nuclei located in mesoporous organic/inorganic hybrid materials, at several hundreds of nanometers from stable radicals (TOTAPOL) trapped in the surrounding frozen disordered water. The approach is demonstrated using mesoporous silica nanoparticles (MSN), functionalized with 3-(N-phenylureido)propyl (PUP) groups, filled with the surfactant cetyltrimethylammonium bromide (CTAB). The DNP-enhanced proton magnetization is transported into the mesopores via 1Hâ1H spin diffusion and transferred to rare spins by cross-polarization, yielding signal enhancements Δon/off of around 8. When the CTAB molecules are extracted, so that the radicals can enter the mesopores, the enhancements increase to Δon/off â 30 for both nuclei. A quantitative analysis of the signal enhancements in MSN with and without surfactant is based on a one-dimensional proton spin diffusion model. The effect of solvent deuteration is also investigated
Structural factors controlling the spin-spin exchange coupling: EPR spectroscopic studies of highly asymmetric trityl-nitroxide biradicals
Highly asymmetric exchange-coupled biradicals, like the trityl-nitroxides (TN), possess particular magnetic properties opening new possibilities for their application in biophysical, physicochemical and biological studies. In the present work, we investigated the effect of the linker length on the spin-spin coupling interaction in TN biradicals using the newly synthesized biradicals CT02-GT, CT02-AT, CT02-VT and CT02-PPT as well as the previously reported biradicals TNN14 and TN1. Results show that the magnitude of the spin-spin interaction (J) can be easily tuned from ~ 4 G (conformer 1 in CT02-PPT) to over 1200 G (in TNN14) using various linkers separating the two radical moieties and with varying temperature. Computer simulation of EPR spectra was carried out to directly estimate J values of the TN biradicals. In addition to the spin-spin coupling interaction of TN biradicals, their g, hyperfine splitting and zero-field splitting interactions were explored at low temperature (220 K). Our present study clearly shows that the spin-spin interaction variation as a function of linker distance and temperature provides an effective strategy to develop new TN biradicals which can find wide applications in relevant fields
Transition metal-like carbocatalyst
Catalytic cleavage of strong bonds including hydrogen-hydrogen, carbon-oxygen, and carbon-hydrogen bonds is a highly desired yet challenging fundamental transformation for the production of chemicals and fuels. Transition metal-containing catalysts are employed, although accompanied with poor selectivity in hydrotreatment. Here we report metal-free nitrogen-assembly carbons (NACs) with closely-placed graphitic nitrogen as active sites, achieving dihydrogen dissociation and subsequent transformation of oxygenates. NACs exhibit high selectivity towards alkylarenes for hydrogenolysis of aryl ethers as model bio-oxygenates without over-hydrogeneration of arenes. Activities originate from cooperating graphitic nitrogen dopants induced by the diamine precursors, as demonstrated in mechanistic and computational studies. We further show that the NAC catalyst is versatile for dehydrogenation of ethylbenzene and tetrahydroquinoline as well as for hydrogenation of common unsaturated functionalities, including ketone, alkene, alkyne, and nitro groups. The discovery of nitrogen assembly as active sites can open up broad opportunities for rational design of new metal-free catalysts for challenging chemical reactions.The Ames Laboratory is operated for the U.S. DOE by Iowa State University under Contract No. DEâAC02â07CH11358. The computational simulations were performed at the OU Supercomputing Center for Education and Research and the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility, and were supported by the U.S. Department of Energy, Basic Energy Sciences (Grant DE-SC0020300).
Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye
Characterization of environmental factors' influence on microbial ecology of sliced cooked ham.
RĂ©duire le sel et le nitrite utilisĂ©s pour la conservation du jambon est un enjeu de santĂ© publique, mais cette rĂ©duction est susceptible de modifier les Ă©cosystĂšmes microbiens et de favoriser le dĂ©veloppement de lâaltĂ©ration des produits. Lâobjectif de ces travaux Ă©tait de caractĂ©riser i) les communautĂ©s microbiennes de jambons issus dâune usine de fabrication ii) leurs productions de mĂ©tabolites dâaltĂ©ration et de prĂ©voir lâĂ©volution de ces deux facteurs dans le cadre dâune rĂ©duction de sel et de nitrite.Parmi les paramĂštres de production Ă©tudiĂ©s, nous avons montrĂ© que la ligne de tranchage Ă©tait un facteur capital. Deux grands profils de communautĂ©s ont Ă©tĂ© observĂ©s Ă la date limite de conservation en fonction de la ligne de tranchage, composĂ©s de neuf espĂšces reprĂ©sentant 95% dâabondance relative dans les Ă©chantillons. La prĂ©sence de ces espĂšces Ă©tait corrĂ©lĂ©e Ă diffĂ©rents profils de production de mĂ©tabolites issus de la fermentation du pyruvate.Sur la base des espĂšces identifiĂ©es, nous avons Ă©laborĂ© une communautĂ© synthĂ©tique que nous avons inoculĂ©e sur un milieu de jambon synthĂ©tique Ă diffĂ©rentes concentrations en sel et en nitrite. Cette approche dâĂ©cologie synthĂ©tique a permis de montrer quâune rĂ©duction en deçà du seuil de 12 g/kg de sel et de 25-30 mg/kg de nitrite entraĂźnait un dĂ©sĂ©quilibre dâabondances liĂ© Ă une croissance exponentielle des Leuconostoc et Ă une diminution de la croissance des Carnobacterium. Ce dĂ©sĂ©quilibre sâaccompagnait dâune augmentation de la production dâĂ©thanol et dâacide D-lactique de 30%, suggĂ©rant un risque dâaltĂ©ration des jambons plus Ă©levĂ© Ă ces concentrations. Nous avons ensuite testĂ© lâeffet de ces concentrations Ă lâĂ©chelle pilote de production. Les comportements microbiens Ă©taient trĂšs diffĂ©rents selon les profils de communautĂ©s de jambons issus des deux lignes de tranchage. Pour le premier profil, un comportement similaire Ă celui de lâĂ©cosystĂšme synthĂ©tique a Ă©tĂ© observĂ©, avec un dĂ©sĂ©quilibre dâabondances en dessous du seuil de 12 g/kg de sel et de 25-30 mg/kg de nitrite et une diminution de lâabondance de Carnobacterium divergens. Pour le deuxiĂšme profil, dominĂ© par Serratia proteamaculans, la structure de la communautĂ© Ă©tait trĂšs peu impactĂ©e par une rĂ©duction de sel et de nitrite. Enfin, sur tous les jambons, nous avons observĂ© quâune rĂ©duction de sel et de nitrite favorisait la croissance de levures.Ces travaux mettent en lumiĂšre lâimportance du procĂ©dĂ© sur la structuration des communautĂ©s microbiennes. Ce facteur est Ă prendre en compte pour comprendre lâimpact de tout autre changement environnemental sur les comportements microbiens.Reducing salt and nitrite used to limit cooked ham spoilage is a public health concern, but it can lead to changes in microbial ecosystems and enhance ham spoilage. Our objective was to characterize (i) the microbial communities of hams from a production plant, (ii) the production of spoilage metabolites and to predict how those factors would change in the context of a reduction in the salt and the nitrite content. Among the process parameters studied, the slicing line was an important factor. Two profiles of communities were observed at the use-by date according to the slicing line. They were composed of nine species representing 95% of abundance. The presence of those species was correlated with different productions of pyruvate-derived fermentation metabolites.Based on the species identified, we designed a synthetic bacterial community that we inoculated on a synthetic ham-like agar medium with different salt and nitrite concentrations. This synthetic ecology approach showed that a reduction under 12 g/kg of salt and 25-30 mg/kg of nitrite correlated with a stronger species disequilibrium, associated with an exponential Leuconostoc growth and a decreased Carnobacterium growth. This disequilibrium was correlated to a 30% increase of ethanol and D-lactic acid production, which suggests a higher spoilage risk for hams at those concentrations. We then tested those concentrations in industrial condition of production. Microbial behavior was very different according to the profiles of community of hams sliced on the different lines. For the first profile, the behavior of the community was similar to the one observed in the synthetic ecosystem: we observed a disequilibrium of species abundance under 12 g/kg of salt and 25-30 mg/kg of nitrite and a decrease in Carnobacterium divergens abundance. For the second profile, dominated by Serratia proteamaculans, community structure was only slightly affected by a reduction of salt and nitrite. Finally, we observed that reducing the salt and the nitrite content increased yeasts growth.This work highlights the importance of process in the structuration of microbial communities in the final product. This factor is to take into account to understand the impact of any other environmental change on microbial behavior
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