258 results on '"F, Portier"'
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2. Emission of Photon Multiplets by a dc-Biased Superconducting Circuit
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G. C. Ménard, A. Peugeot, C. Padurariu, C. Rolland, B. Kubala, Y. Mukharsky, Z. Iftikhar, C. Altimiras, P. Roche, H. le Sueur, P. Joyez, D. Vion, D. Esteve, J. Ankerhold, and F. Portier
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Physics ,QC1-999 - Abstract
We observe the emission of bunches of k≥1 photons by a circuit made of a microwave resonator in series with a voltage-biased tunable Josephson junction. The bunches are emitted at specific values V_{k} of the bias voltage, for which each Cooper pair tunneling across the junction creates exactly k photons in the resonator. The latter is a microfabricated spiral coil which resonates and leaks photons at 4.4 GHz in a measurement line. Its characteristic impedance of 1.97 kΩ is high enough to reach a strong junction-resonator coupling and a bright emission of the k-photon bunches. We show that a rotating-wave approximation treatment of the system accounts quantitatively for the observed radiation intensity, from k=1 to 6, and over 3 orders of magnitude when varying the Josephson energy E_{J}. We also measure the second-order correlation function of the radiated microwave to determine its Fano factor F_{k}, which in the low E_{J} limit confirms with F_{k}≃k the emission of k-photon bunches. At larger E_{J}, a more complex behavior is observed in quantitative agreement with numerical simulations.
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- 2022
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3. Generating Two Continuous Entangled Microwave Beams Using a dc-Biased Josephson Junction
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A. Peugeot, G. Ménard, S. Dambach, M. Westig, B. Kubala, Y. Mukharsky, C. Altimiras, P. Joyez, D. Vion, P. Roche, D. Esteve, P. Milman, J. Leppäkangas, G. Johansson, M. Hofheinz, J. Ankerhold, and F. Portier
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Physics ,QC1-999 - Abstract
We show experimentally that a dc-biased Josephson junction in series with two microwave resonators emits entangled beams of microwaves leaking out of the resonators. In the absence of a stationary phase reference for characterizing the entanglement of the outgoing beams, we measure second-order coherence functions to prove the entanglement. The experimental results are found in quantitative agreement with theory, proving that the low-frequency noise of the dc bias is the main limitation for the coherence time of the entangled beams. This agreement allows us to evaluate the entropy of entanglement of the resonators, estimate the entanglement flux at their output, and to identify the improvements that could bring this device closer to a useful bright source of entangled microwaves for quantum-technological applications.
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- 2021
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4. Reply to 'Comment on ‘Absence of a Dissipative Quantum Phase Transition in Josephson Junctions'’
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A. Murani, N. Bourlet, H. le Sueur, F. Portier, C. Altimiras, D. Esteve, H. Grabert, J. Stockburger, J. Ankerhold, and P. Joyez
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Physics ,QC1-999 - Abstract
In their Comment [P. Hakonen and E. B. Sonin, preceding comment, Phys. Rev. X 11, 018001 (2021)PRXHAE2160-3308], Hakonen and Sonin (HS) object to our conclusion on the absence of a dissipation-induced superconducting-to-insulating quantum phase transition (DQPT) in resistively shunted Josephson junctions (RSJJs) originally predicted by Schmid and Bulgadaev (SB). Their objections are based on the account they make of a theory explaining the DQPT in terms of Bloch bands which was developed in the 1980s and early 1990s. In this Reply, we point to several issues in the Comment which undermine the objections HS formulate against our work.
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- 2021
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5. Absence of a Dissipative Quantum Phase Transition in Josephson Junctions
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A. Murani, N. Bourlet, H. le Sueur, F. Portier, C. Altimiras, D. Esteve, H. Grabert, J. Stockburger, J. Ankerhold, and P. Joyez
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Physics ,QC1-999 - Abstract
Half a century after its discovery, the Josephson junction has become the most important nonlinear quantum electronic component at our disposal. It has helped reshape the International System of Units around quantum effects and is used in scores of quantum devices. By itself, the use of Josephson junctions in volt metrology seems to imply an exquisite understanding of the component in every aspect. Yet, surprisingly, there have been long-standing subtle issues regarding the modeling of the interaction of a junction with its electromagnetic environment. Here, we find that a Josephson junction connected to a resistor does not become insulating beyond a given value of the resistance due to a dissipative quantum phase transition, as is commonly believed. Our work clarifies how this key quantum component behaves in the presence of a dissipative environment and provides a comprehensive and consistent picture, notably regarding the treatment of its phase.
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- 2020
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6. Indexing Permafrost Soil Organic Matter Degradation Using High-Resolution Mass Spectrometry.
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Benjamin F Mann, Hongmei Chen, Elizabeth M Herndon, Rosalie K Chu, Nikola Tolic, Evan F Portier, Taniya Roy Chowdhury, Errol W Robinson, Stephen J Callister, Stan D Wullschleger, David E Graham, Liyuan Liang, and Baohua Gu
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Medicine ,Science - Abstract
Microbial degradation of soil organic matter (SOM) is a key process for terrestrial carbon cycling, although the molecular details of these transformations remain unclear. This study reports the application of ultrahigh resolution mass spectrometry to profile the molecular composition of SOM and its degradation during a simulated warming experiment. A soil sample, collected near Barrow, Alaska, USA, was subjected to a 40-day incubation under anoxic conditions and analyzed before and after the incubation to determine changes of SOM composition. A CHO index based on molecular C, H, and O data was utilized to codify SOM components according to their observed degradation potentials. Compounds with a CHO index score between -1 and 0 in a water-soluble fraction (WSF) demonstrated high degradation potential, with a highest shift of CHO index occurred in the N-containing group of compounds, while similar stoichiometries in a base-soluble fraction (BSF) did not. Additionally, compared with the classical H:C vs O:C van Krevelen diagram, CHO index allowed for direct visualization of the distribution of heteroatoms such as N in the identified SOM compounds. We demonstrate that CHO index is useful not only in characterizing arctic SOM at the molecular level but also enabling quantitative description of SOM degradation, thereby facilitating incorporation of the high resolution MS datasets to future mechanistic models of SOM degradation and prediction of greenhouse gas emissions.
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- 2015
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7. Interacting Electrodynamics of Short Coherent Conductors in Quantum Circuits
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C. Altimiras, F. Portier, and P. Joyez
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Physics ,QC1-999 - Abstract
When combining lumped mesoscopic electronic components to form a circuit, quantum fluctuations of electrical quantities lead to a nonlinear electromagnetic interaction between the components, which is generally not understood. The Landauer-Büttiker formalism that is frequently used to describe noninteracting coherent mesoscopic components is not directly suited to describe such circuits since it assumes perfect voltage bias, i.e., the absence of fluctuations. Here, we show that for short coherent conductors of arbitrary transmission, the Landauer-Büttiker formalism can be extended to take into account quantum voltage fluctuations similarly to what is done for tunnel junctions. The electrodynamics of the whole circuit is then formally worked out disregarding the non-Gaussianity of fluctuations. This reveals how the aforementioned nonlinear interaction operates in short coherent conductors: Voltage fluctuations induce a reduction of conductance through the phenomenon of dynamical Coulomb blockade, but they also modify their internal density of states, leading to an additional electrostatic modification of the transmission. Using this approach, we can quantitatively account for conductance measurements performed on quantum point contacts in series with impedances of the order of R_{K}=h/e^{2}. Our work should enable a better engineering of quantum circuits with targeted properties.
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- 2016
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8. Screening for obstructive sleep apnea (OSA) in patients referred for bariatric surgery
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Raphaël Lukaszewicz, Maxime Patout, F. Portier, Samuel Dolidon, Marie Netchitailo, Antoine Grégoire, and Antoine Cuvelier
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Obstructive sleep apnea ,Pediatrics ,medicine.medical_specialty ,business.industry ,medicine ,In patient ,medicine.disease ,business - Published
- 2019
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9. Le robot pourrait-il améliorer l’accessibilité à la chirurgie hépatique mini-invasive ? Résultats d’une étude bi-institutionnelle comparant des hépatectomies par voies laparoscopiques et robotiques
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C. Magallon, A. Camerlo, F. Portier, M. Palazzo, Brice Gayet, E. Tribillon, David Fuks, R. Fara, and C. Julien
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Surgery - Abstract
Introduction Le but de l’etude etait de comparer les caracteristiques peroperatoires et les resultats a court terme apres hepatectomie laparoscopique (HL) et robotique (HR). Methodes De 2015 a 2020, les patients operes d’une hepatectomie laparoscopique ou robotique dans deux centres tertiaires ont ete inclus. Les caracteristiques demographiques, operatoires et les resultats a court terme ont ete compares. Les patients du groupe HL ont ete apparies au groupe HR selon les caracteristiques demographiques, chirurgicales et le score IMM. Resultats Au total, 249 HL et 50 HR ont ete incluses. L’HL etait associee a une duree operatoire plus courte (193,5 ± 90,0 vs 252,7 ± 91,6 min, p Conclusion La robotique pourrait permettre des hepatectomies complexes pour des chirurgiens moins experimentes en chirurgie laparoscopique.
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- 2021
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10. Central Sleep Apnea and Stiff Person Syndrome: A Case Report
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Marie Netchitailo, Jacques Senant, F. Portier, and Catherine Tardif
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Central sleep apnea ,medicine.diagnostic_test ,business.industry ,MEDLINE ,Sleep apnea ,Electromyography ,Polysomnography ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,030228 respiratory system ,medicine ,Physical therapy ,business ,030217 neurology & neurosurgery ,Stiff person syndrome - Published
- 2017
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11. Dépistage des formes sévères du syndrome d’apnée du sommeil chez les patients candidats à la chirurgie bariatrique
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Marie Netchitailo, R. Lukaszewicz, F. Portier, H. Morisse, A. Gillibert, A. Grégoire, S. Dolidon, Maxime Patout, and Antoine Cuvelier
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Pulmonary and Respiratory Medicine - Abstract
Introduction Le depistage du syndrome d’apnee obstructive du sommeil (SAOS) est recommande avant la chirurgie bariatrique. Face a l’augmentation de l’incidence de l’obesite et a un acces limite a la polygraphie respiratoire, une approche plus pragmatique est necessaire. L’objectif de notre etude etait de determiner si l’evaluation clinique diurne et l’oxymetrie nocturne permettait d’exclure avec certitude le diagnostic de SAOS severe avant la chirurgie bariatrique. Methodes Etude monocentrique sur une cohorte de patients adresse pour evaluation pneumologique avant chirurgie bariatrique entre mai 2017 et avril 2018. Les outils de depistage etaient valides sur une population similaire a partir d’une cohorte de validation externe de notre centre hospitalo-universitaire. Resultats Sur 120 patients adresses pour evaluation pneumologique, 99 (83 %) ont beneficie d’une polygraphie. Vingt (20 %) avait un SAOS severe. Le Neck-Sat score (tour de cou [cm] + [100-Saturation en O2 arterielle]) au seuil de 46,3 avait une sensibilite, specificite, valeur predictive positive et negative de 95 %, 75 %, 51 %, 98 %. Ce score avait de meilleures performances que le STOP-BANG et le questionnaire de Berlin (aire sous la courbe : 0,879 vs 0,716 vs 0,623). L’oxymetrie nocturne seule, avec un index de desaturation en O2 au seuil de 29/h, avait une sensibilite, specificite, valeur predictive positive et negative de 100 %, 95 %, 83 %, 100 %. La validation externe a montre des resultats similaires pour les deux outils de depistage. L’utilisation de ces outils de depistages auraient pu reduire le nombre de polygraphies realisees de 63 % pour le Neck-Sat et de 76 % pour l’oxymetrie nocturne. Conclusion Le diagnostic de SAOS severe peut etre elimine a l’aide d’outils plus simple et plus accessible que la polygraphie ventilatoire nocturne chez les patients adresses pour evaluation pneumologique avant chirurgie bariatrique.
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- 2020
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12. Sleep quality during home noninvasive ventilation (NIV)
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Jasmine Sutter, F. Portier, Antoine Cuvelier, Julien Maris, Raphaël Lukaszewicz, Adriana Portmann, and Maxime Patout
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medicine.medical_specialty ,Sleep quality ,business.industry ,Emergency medicine ,Medicine ,Noninvasive ventilation ,business - Published
- 2018
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13. Fixed-pressure CPAP versus auto-adjusting CPAP : Comparison of efficacy in obstructive sleep apnoea (OSAS) according to the individual level of efficient pressure and pressure variability
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Franck Soyez, F. Portier, Pierre Ingrand, C. Launois, Francis Martin, Lorent Portel, Lionel Lerousseau, Didier Alfandary, Marie-Françoise Vecchierini, Frédéric Gagnadoux, Renaud Tamisier, François Codron, Magalie Mercy, Anne Mallart, Claudio Rabec, Vanessa Bironneau, S. Pontier, V. Levrat, Valérie Attali, Guy Auregan, Didier Recart, Carmen Iamandi, Jean-Claude Meurice, and Frederic Goutorbe
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business.industry ,Anesthesia ,Variable pressure ,Medicine ,Mean age ,business ,Individual level - Abstract
Introduction : There are currently only little data available on the factors predicting the respective efficacy of fixed CPAP (FP-CPAP) or automated CPAP (APAP) for OSAS treatment. Aims and objectives : We evaluated the efficacy of a 3month-period treatment with FP-CPAP versus APAP on a composit criteria involving apnoea/ hyponoea index (AHI) and the Epworth score (ESS), according to the level of effective pressure (Peff) as well as pressure variability (Pvar). Methods : A multicenter prospective controlled study was conducted in 22 academic and non academic french centers. Initial clinical and polygraphic data were obtained before initiating a 7-day period using APAP delivering a variable pressure between 4 and 20 cm Hg. Then, patients were randomised to either FP-CPAP or APAP used during 3 months, and the data obtained at the end of the study period were analysed according to the inital level of Peff and Pvar. Results : 616 patients (mean age : 56.8 yrs ± 11.2, mean AHI : 51.7/h ± 20.8) were included. CPAP compliance was the same in both groups (FP-CPAP : 5.78h ± 1.9 vs APAP : 5.85h± 1.9) with an identical efficacy on AHI and the ESS (FP-CPAP : 6.11/h ± 7.94 and 6.02 ± 4.37, and APAP 5.71/h ± 6.75 and 6.05 ± 4.5). Despite the lack of influence of Pvar on FP-CPAP vs APAP efficiency, a greater initial pressure variability was associated with a significant higher residual AHI whatever the mode of CPAP applied. Conclusion : The efficiency of FP-CPAP and APAP was identical on OSAS improvement after 3 months of treatment, independently of initial level of effective pressure and variability.
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- 2018
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14. Chronic respiratory failure in myotonic dystrophy type 1 (DM1): Incidence & risk factors
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Antoine Cuvelier, Anne-Marie Guerrot, Marie-Anne Melone, Marie Netchitailo, Lucie Guyant-Maréchal, Alice Goldenberg, Maxime Patout, Sarah Grotto, Catherine Tardif, F. Portier, and Anne-Laure Bedat-Millet
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musculoskeletal diseases ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,business.industry ,Incidence (epidemiology) ,University hospital ,Single Center ,medicine.disease ,Myotonic dystrophy ,Disease severity ,Internal medicine ,medicine ,Cardiology ,Respiratory system ,Muscular dystrophy ,business ,Chronic respiratory failure - Abstract
Background: DM1 is the most frequent adult-onset muscular dystrophy. CTG length expansion has been correlated with disease severity. Incidence of chronic respiratory failure (CRF) is unknown. The aim of this study was to assess the incidence of CRF and its risk factors. Methods: Retrospective single center observational study including all patients with proven DM1 followed in Rouen University Hospital between 2000 and 2016. CRF was defined by home NIV requirement. Results: Eighty-six patients with DM1 were identified. Of these, 26 (30%) had CRF. Comparison of patients with or without CRF can be found in table 1. Adherence to home NIV was 5.6±3.6hours/day. CTG length was correlated to daytime PaCO 2 (r=0.366; p=0.01), sniff nasal inspiratory pressure (SNIP) (r=-0.391; p=0.008), maximal inspiratory pressure (MIP) (r=-0.530; p=0.001), maximal expiratory pressure (MEP) (r=-0.512; p=0.001) and cough peak flow (CPF) (r=-0.433; p=0.015). Conclusion: CRF is frequent in patients with DM1 and should be screened in all patients. CTG length expansion is correlated with respiratory muscles impairment but cannot predict home NIV requirement.
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- 2017
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15. Conséquences de l’ajout d’un système d’humidification chez les patients traités par ventilation non invasive au long cours : un essai contrôlé randomisé
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A. Bertier, Adrien Kerfourn, Emeline Fresnel, Antoine Cuvelier, F. Portier, A. Portmann, and Maxime Patout
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Pulmonary and Respiratory Medicine - Abstract
Introduction La ventilation non invasive (VNI) au long cours est usuellement prescrite avec un systeme d’humidification integre pour pallier a la sensation de secheresse buccale. Cependant, aucune etude n’a demontre le benefice d’un tel dispositif en VNI. L’objectif de notre etude etait d’evaluer les benefices d’un systeme d’humidification sur l’observance, les symptomes de secheresse buccale et l’efficacite de la VNI a 2 mois de la mise en place. Methodes Etude monocentrique controlee randomisee menee entre mai 2018 et janvier 2019 incluant de maniere consecutive les patients adresses pour mise en place d’une VNI au long cours ( NCT03561974 ). Les patients etaient randomises en deux groupes : avec un systeme d’humidification (groupe humidification) ou sans (groupe controle), avec une stratification sur l’etiologie de l’insuffisance respiratoire motivant la mise en place de la VNI. Les criteres de jugement etaient evalues a deux mois de l’initiation de la VNI (M2). Resultats Quarante-sept patients ont ete screenes et 33 (70 %) inclus. L’âge moyen etait de 66 ± 12 ans. Les pathologies respiratoires chroniques sous-jacentes etaient : syndrome obesite-hypoventilation (n = 12), BPCO (n = 8), pathologie neuromusculaire ou restrictive (n = 8), BPCO-SAOS (n = 5). A l’inclusion il n’existait pas de difference significative entre les deux groupes. A M2, 14 patients ont ete reevalues dans le groupe humidification et 16 dans le groupe controle. A M2, la compliance etait de : 5,7 ± 3,3 dans le groupe humidification et 5,3 ± 1,6 heures/jour dans le groupe controle (p = 0,683). La secheresse buccale evaluee par une echelle analogique etait : 6,1 ± 2,7 sur 10 dans le groupe humidification et 6,3 ± 3,1 dans le groupe controle (p = 0,869). Le changement de la qualite de vie (QDV) evalue par le questionnaire SRI (insuffisance respiratoire severe) etait : +5 ± 24 dans le groupe Humidification vs −11 ± 22 dans le groupe controle (p = 0,125). L’amelioration de la PaCO2 diurne etait : −0,36 ± 0,87 dans le groupe Humidification vs. −0,02 ± 0,68 kPa dans le groupe controle (p = 0,260). Conclusion L’ajout d’un systeme d’humidification n’ameliore pas significativement la compliance au traitement, la QDV ou l’efficacite de la VNI. Cependant, cette absence de difference pourrait etre liee a un manque de puissance statistique.
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- 2020
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16. Insuffisance respiratoire chronique chez les patients atteints de dystrophie myotonique de type 1 (DM1) : incidence et facteurs de risque
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Catherine Tardif, A.-M. Guerrot, Maxime Patout, L. Guyant-Maréchal, S. Grotto, F. Portier, M.A. Melone, Marie Netchitailo, Antoine Cuvelier, A. Goldenberg, and A.-L. Bédat-Millet
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Pulmonary and Respiratory Medicine - Abstract
Introduction La DM1 est liee a l’expression de repetition de trinucleotides cytosine-thymine-guanine (CTG) dans la region non codante du gene DMPK du chromosome 19. L’objectif de cette etude etait d’evaluer l’importance de l’alteration musculaire respiratoire, l’incidence de l’insuffisance respiratoire chronique (IRC) et leur correlation avec le nombre de repetition de triplet CTG. Methodes Etude observationnelle incluant l’ensemble des patients DM1 suivis entre 2000 et 2017 au centre de competence des maladies neuromusculaires du CHU de Rouen. Les patients disposaient tous d’un diagnostic clinique realise par un neurologue et d’une analyse genetique. La force musculaire squelettique etait evaluee par le muscular impairement rating scale (MIRS). L’IRC etait definie par une hypercapnie > 45 mmHg (6 kPa) ou le recours a une ventilation non invasive a domicile. Resultats Quatre vingt-douze patients DM1 ont ete identifies. Trente-neuf patients (40 %) avaient une IRC. Le Tableau 1 rapporte les principales caracteristiques des patients avec et sans IRC. La longueur moyenne de repetition CTG, la severite de la maladie et l’âge etaient des facteurs associes a la survenue de l’IRC. La longueur de repetition CTG etait correlee a l’hypercapnie (r = 0,366 ; p = 0,01), au deficit de la pression inspiratoire de reniflement (Sniff test) (r = −0,391 ; p = 0,008), au deficit de la pression maximale inspiratoire (r = −0,530 ; p = 0,001), au deficit de la pression musculaire expiratoire (r = −0,512 ; p = 0,001) et du DEP a la toux (r = −0,433 ; p = 0,015). Conclusion L’IRC est frequente chez les patients DM1. Les patients DM1 requierent une evaluation et un suivi pneumologique precoces. La longueur de repetitions CTG est correlee a l’alteration de force musculaire respiratoire et a la survenue de l’IRC.
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- 2018
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17. Anomalies respiratoires au cours du syndrome de Marfan
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F. Portier, Marie Netchitailo, F. Doguet, D. Maure, Antoine Cuvelier, and Maxime Patout
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Pulmonary and Respiratory Medicine - Abstract
Introduction Le syndrome de Marfan est une maladie genetique rare aboutissant a une production de fibrilline 1 alteree et un tissu conjonctif plus fragile que la normale. Les atteintes cliniques les plus frequentes sont cardiovasculaires, oculaires et squelettiques mais l’ensemble des organes peut etre touche et notamment l’appareil respiratoire. Cette etude visait a identifier la prevalence des atteintes respiratoires au sein d’une cohorte active de patients atteints du syndrome de Marfan. Methodes La cohorte etait composee de 82 patients atteints du syndrome de Marfan suivis entre le 1er janvier 2000 et le 1er juin 2016 au CHU de Rouen. L’âge moyen etait de 38,2 ans et le sex-ratio de 0,95. Une atteinte cardiovasculaire etait presente chez 68 patients dont la moitie avait beneficie d’une chirurgie aortique. Les patients ayant beneficie d’une evaluation pneumologique etaient repartis en deux groupes :–un groupe « Depistage » avec17 patients naifs de toute evaluation pneumologique. Ces patients ont ete recus en consultation de pneumologie avec realisation d’une exploration fonctionnelle respiratoire et proposition de realisation d’une polygraphie ventilatoire nocturne ;–un groupe « Suivi » compose de 13 patients ayant deja beneficie d’une evaluation pneumologique au cours de leur suivi medical. Resultats Un syndrome d’apnee du sommeil defini par un IAH > 5/ h a ete retrouve chez 14 des 82 patients de l’etude avec un IAH moyen a 11,8/ h (soit 17,1 % de la cohorte et 73,7 % des patients ayant beneficie d’une polygraphie ventilatoire). Ce diagnostic etait significativement plus frequent dans le groupe « Suivi » (11 patients, soit 84,6 %) que dans le groupe « Depistage » (3 patients, soit 17,6 %) (p = 0,0006). Chez les patients operes de l’aorte, 29,4 % avaient un IAH moyen a 17,8/ h contre seulement 8,3 % des non operes (IAH moyen a 5,2/h, p = 0,0174). Les autres atteintes respiratoires (pneumothorax, deformation thoracique, insuffisance respiratoire chronique, malformations vasculaires pulmonaires et infections respiratoires) etaient representees dans des proportions comparables aux donnees de la litterature. Conclusion La presence d’evenements respiratoires nocturnes est la principale anomalie pneumologique retrouvee au cours du syndrome de Marfan. Il apparait necessaire de realiser une polygraphie ventilatoire nocturne en cas de symptomatologie evocatrice ou d’atteinte cardiovasculaire severe.
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- 2019
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18. Les otites séromuqueuses
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E. Sauvaget, F. Portier, and P. Tran Ba Huy
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Gynecology ,medicine.medical_specialty ,Otorhinolaryngology ,business.industry ,Middle ear disease ,medicine ,Surgery ,business - Abstract
Resume Objectif Les otites seromuqueuses (OSM) se definissent par la presence d'une effusion des cavites de l'oreille moyenne durant plus de trois semaines. Si le diagnostic ne pose pas de probleme, la pathogenie et l'attitude therapeutique restent incertaines et controversees. Materiels et methodes A partir d'une revue de la litterature, les questions concernant la physiopathogenie et l'attitude therapeutique sont etudiees. Resultats Exception faite des otites traumatiques, l'effusion correspond a un exsudat lie a une metaplasie mucipare. Le facteur causal essentiel est une inflammation de l'oreille moyenne qui fait suite a une infection virale ou bacterienne. Cette inflammation modifierait les fonctions de transports ioniques du sodium. La responsabilite de l'OSM dans la genese des diverses formes d'otites chroniques reste controversee. Le traitement n'est justifie que lorsque l'OSM est chronique, autrement dit apres une observation de quelques mois, visant a reduire les causes de l'inflammation et traiter l'effusion. La prevention et le traitement des causes de l'inflammation restent difficiles. En effet, les rhinopharyngites sont majoritairement d'origine virale et ne peuvent etre prevenues. Le traitement de l'effusion est justifie afin de prevenir les sequelles locales et d'eviter des troubles de langage. L'ATT demeure l'unique traitement efficace, en levant la depression tympanique, en corrigeant le dysfonctionnement tubaire secondaire et en restaurant la clairance mucociliaire. L'adenoidectomie et/ou l'amygdalectomie n'ont pas d'efficacite sur l'OSM mais, associees a l'ATT, diminueraient les OMA recidivantes. Conclusion L'OSM reste une pathologie tres frequente, dont le seul traitement efficace repose sur l'ATT.
- Published
- 2007
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19. Ventilation non invasive au long cours et sommeil
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J.-F. Muir, Catherine Viacroze, Antoine Cuvelier, F. Portier, and C. Molano
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Behavioral Neuroscience ,Neuropsychology and Physiological Psychology ,Neurology ,Cognitive Neuroscience ,Neurology (clinical) - Abstract
Resume La ventilation non invasive (VNI) est devenue incontournable dans le cadre de la prise en charge des decompensations aigues des insuffisants respiratoires chroniques (IRC) en secteur de reanimation ou de soins intensifs. Elle concerne une grande majorite des nouveaux malades ventiles au long cours a domicile quelle que soit l’etiologie de leur IRC. Alors que de nombreux travaux ont etudie l’incidence de la ventilation en pression positive continue sur le sommeil du syndrome d’apnees obstructives du sommeil (SAS), rares sont les etudes qui se sont interessees a l’incidence de la VNI sur le sommeil, que ce soit en etat aigu ou en etat chronique. De meme, on ne connait que tres peu d’elements sur les effets du sommeil lui-meme sur l’efficacite de la VNI. L’efficacite de la VNI au long cours, en particulier l’amelioration de la qualite de vie qui lui est associee chez les IRC restrictifs, est sous-tendue par l’amelioration de la qualite du sommeil qu’elle induit par la correction des acces hypoxemiques, des apnees eventuellement associees et surtout de l’hypoventilation alveolaire presents en phase nocturne.
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- 2006
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20. Lower respiratory tract foreign bodies: A retrospective review of morbidity, mortality and first aid management
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P. Attal, F. Portier, Jean-Baptiste Charrier, C. Le Pajolec, S. Bobin, D. Devictor, I. Kerurien Lebret, and I. Rouillon
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Male ,medicine.medical_specialty ,Respiratory System ,MEDLINE ,law.invention ,Heimlich Maneuver ,law ,Intensive care ,medicine ,First Aid ,Humans ,Child ,Intensive care medicine ,Asphyxia ,business.industry ,Incidence ,Infant ,General Medicine ,Foreign Bodies ,medicine.disease ,Intensive care unit ,medicine.anatomical_structure ,Otorhinolaryngology ,Child, Preschool ,Pediatrics, Perinatology and Child Health ,Female ,France ,medicine.symptom ,Foreign body ,business ,Respiratory tract ,First aid - Abstract
Summary Objectives The authors describe 28 pediatric cases of foreign body inhalation requiring treatment in intensive care units between 1987 and 1999. The purpose of this study was: (1) to analyze the circumstances, diagnostic difficulties and initial treatment of serious foreign bodies and (2) to compare our series with other literature descriptions and define principles for optimal prevention and initial treatment. Methods Twenty-one children presented a penetration syndrome, which was responsible in 13 cases for asphyxia with cardiorespiratory arrest. All these children died, regardless of the initial treatment. Seven children were hospitalized for apparent asthmatic symptoms that did not respond to traditional treatment. Results The inefficiency of external extraction methods like the Heimlich maneuver and the mean delay between clinical signs and initial treatment lead us to propose a new strategy for the emergency treatment of foreign bodies with asphyxia. Conclusions We recommend that emergency teams promote the use of a laryngoscope and Magill forceps. Flexible endoscopy is still recommended as the appropriate diagnostic tool to eliminate doubt in the case of a first severe asthma attack.
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- 2006
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21. Maladie de Méniè;re
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Patrice Tran Ba Huy, S. Hervé, F. Portier, Philippe Herman, Sophie Tronche, and Catherine de Waele
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Gynecology ,medicine.medical_specialty ,business.industry ,Medicine ,business - Published
- 2006
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22. Endoscopie et traitement chirurgical des macroadénomes hypophysaires endo- et suprasellaires invasifs
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Fabrice Parker, B. Baussart, Ph. Chanson, Nozar Aghakhani, M. Tadié, and F. Portier
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Surgery ,Neurology (clinical) - Abstract
Resume Objectifs Les macroadenomes hypophysaires endo- et suprasellaires invasifs restent de traitement chirurgical difficile. A partir d’une serie retrospective de 13 patients operes consecutivement, les apports et les limites de l’endoscopie dans la chirurgie des macroadenomes hypophysaires invasifs ont ete evalues. Methodes L’abord endonasal avec incision intersepto-columellaire etait mene sous endoscopie (optique 0). L’exerese de la lesion etait realisee sous microscope operatoire. Au terme de l’exerese sous microscope, un endoscope rigide (optique 30°) etait introduit en endo- et suprasellaire, afin d’evaluer la persistance d’un reliquat adenomateux. En fonction des possibilites techniques, ce dernier etait retire. Resultats Aucune complication rhinologique secondaire a la voie d’abord n’a ete observee. Pour 7 patients, l’exploration endoscopique endo- et suprasellaire a montre la presence d’un reliquat tumoral qui a pu etre reseque dans chaque cas. Lors de ce complement d’exerese, une fuite de LCR s’est produite a 2 reprises. En postoperatoire, on relevait 2 cas de diabete insipide prolonge et deux rhinoliquorrhees. L’analyse des IRM postoperatoires retrouvait 23 % d’exerese complete (3/13), 54 % d’exerese comprise entre 75 % et 100 % du volume tumoral (7/13), 8 % d’exerese comprise entre 50 % et 75 % du volume tumoral (1/13), 15 % d’exerese evaluee a 50 % du volume tumoral (2/13). 77 % des patients (10/13) ont donc eu une exerese superieure a 75 %. La duree moyenne du suivi etait de 27,2 mois. Conclusions L’abord endonasal sous endoscopie etait associe a une moindre morbidite rhinologique. L’endoscopie semblait etre une technique interessante en complement du microscope permettant une exploration optimale de la region sellaire. Elle permettait de plus le reperage et la resection de bourgeons tumoraux non visualises au microscope. Cette procedure etait neanmoins associee a un risque supplementaire de rhinorrhee postoperatoire.
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- 2005
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23. Maladie de von Hippel-Lindau : progrès génétiques et cliniques récents
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Nozar Aghakhani, F. Portier, F. Parker, Philippe David, Stéphane Richard, G. Allegre, and K. Marsot-Dupuch
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medicine.medical_specialty ,endocrine system diseases ,Radiological and Ultrasound Technology ,business.industry ,Angiogenesis ,Somatic cell ,Disease ,Neuroendocrine tumors ,urologic and male genital diseases ,medicine.disease ,female genital diseases and pregnancy complications ,Endocrinology ,Germline mutation ,Hypoxia-inducible factors ,Renal cell carcinoma ,Internal medicine ,Hemangioblastoma ,medicine ,Cancer research ,Radiology, Nuclear Medicine and imaging ,Neurology (clinical) ,business ,neoplasms - Abstract
Von Hippel-Lindau (VHL) disease is a hereditary cancer syndrome that predisposes to the development of a panel of highly vascularized tumors including CNS and retinal hemangioblastomas, endolymphatic sac tumors, clear-cell renal cell carcinomas (RCC), pheochromocytomas and pancreatic neuroendocrine tumors. CNS hemangioblastomas and RCC are the two main life-threatening manifestations. The disease is caused by germline mutations in the VHL tumor-suppressor gene that plays a major role in regulating the oxygen-sensing pathway by targeting the hypoxia-inducible factor HIF for degradation in proteasome. Somatic inactivation of the VHL gene occurs also in most sporadic RCC and sporadic CNS hemangioblastomas. The demonstration of the critical role of VHL in angiogenesis is paving the way for the development of new specific drugs that could represent an attractive potential treatment for VHL but also for sporadic RCC and other cancers.
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- 2005
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24. Infections cervicales de l’enfant
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F. Portier and B. Husson
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Radiology, Nuclear Medicine and imaging - Abstract
Resume Les infections cervicales de l’enfant ont des presentations cliniques variees : certaines sont benignes et ne necessitent pas de recours a l’imagerie, d’autres au contraire realisent de veritables urgences qui impliquent la realisation rapide d’examens radiologiques pour guider la prise en charge. Le risque de compression des voies aeriennes, facilement comblees chez le petit enfant est majeur en cas d’infection profonde, l’atteinte vasculaire est egalement possible pouvant etre a l’origine de complications severes. Ces elements ainsi que la situation et l’extension de l’infection doivent etre precises par l’imagerie, quelle que soit la technique utilisee mais en gardant en memoire la necessite de la meilleure information avec une irradiation la plus faible possible.
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- 2005
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25. Diagnóstico por imágenes de los tumores del oído
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K. Marsot-Dupuch, J. Quillard, F. Portier, and M. Gayet-Delacroix
- Abstract
Resumen El estudio de los procesos expansivos del oido se ha visto beneficiado por los progresos de la tomografia computarizada (TC) y de la resonancia magnetica (RM). La RM permite el diagnostico positivo, y ademas, presupone su naturaleza: lesion hipervascular, matriz condroide, quiste epidermoide. La TC permite estimar la extension intrapetrosa. Las posibilidades diagnosticas deben discutirse segun la localizacion, la senal, la densidad y las caracteristicas que presenta la lesion. Las pruebas de imagen permiten el seguimiento de las lesiones, que en la mayoria de los casos solo requieren vigilancia. El crecimiento tumoral es uno de los elementos en favor de la indicacion quirurgica, por lo que la reproducibilidad de las medidas tumorales constituye un dato de extraordinaria utilidad.
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- 2005
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26. Thrombophlébite de la veine ovarienne du post-partum
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Raoul Desbriere, Claude D'Ercole, F. Portier, O. Hartung, Edwin Quarello, and Léon Boubli
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Gynecology ,medicine.medical_specialty ,Chemotherapy ,business.industry ,Vascular disease ,medicine.medical_treatment ,Obstetrics and Gynecology ,General Medicine ,medicine.disease ,Thrombophlebitis ,Text mining ,Reproductive Medicine ,medicine ,Ultrasonography ,Venous disease ,business ,Complication ,Ovarian vein - Abstract
Journal de Gynecologie Obstetrique et Biologie de la Reproduction - Vol. 33 - N° 5 - p. 430-440
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- 2004
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27. Complications méningo-encéphaliques des otites chroniques cholestéatomateuses
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F. Portier, E. Racy, D. Doyon, S. Bobin, E. Lescanne, and B. Lemaire
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Gynecology ,medicine.medical_specialty ,Otorhinolaryngology ,business.industry ,medicine ,Surgery ,business - Published
- 2004
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28. Imagerie des tumeurs de l'oreille
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M. Gayet-Delacroix, J. Quillard, F. Portier, and K. Marsot-Dupuch
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Granular cell tumor ,Otorhinolaryngology ,business.industry ,medicine ,Epidermoid cyst ,LPN and LVN ,Nuclear medicine ,business ,medicine.disease ,Endolymphatic sac tumor ,Exostosis - Abstract
Resume Le bilan des processus expansifs de l'oreille a beneficie de progres en imagerie tomodensitometrique (TDM) et en imagerie par resonance magnetique (IRM). L'IRM permet, outre le diagnostic positif, d'en presupposer la nature : lesion hypervasculaire, matrice chondroide, kyste epidermoide. La TDM permet d'apprecier l'extension intrapetreuse. La gamme diagnostique est a discuter selon l'epicentre de la lesion, le signal, la densite et les particularites de la lesion objectivee. L'imagerie permet le suivi des lesions dont beaucoup ne sont que surveillees. L'accroissement tumoral est un des elements pour choisir une solution chirurgicale, la reproductibilite des mesures tumorales en particulier volumique est donc une donnee a privilegier.
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- 2004
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29. Enfermedad de Ménière
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P. Herman, C. de Waele, P. Tran Ba Huy, S. Tronche, F. Portier, and S. Hervé
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Resumen La enfermedad de Meniere, arquetipo de la enfermedad vertiginosa discapacitante, es una afeccion cuya causa aun se desconoce, a pesar de los numerosos trabajos y publicaciones medicas que se han sucedido desde su primera descripcion, en el siglo XIX. Este trastorno frecuente se caracteriza por un aumento de la cantidad de liquido endolaberintico, que origina una triada clinica patognomonica, constituida por acufenos (zumbidos) unilaterales, del lado del oido afectado, sordera de percepcion del mismo lado, por lo general predominante en las frecuencias graves, y vertigo rotatorio pronunciado de tipo periferico, con nauseas y vomitos. Esta triada aparece en forma de crisis paroxisticas de varias horas de duracion, cuya periodicidad es aleatoria. Entre dos crisis, el paciente no percibe ningun sintoma y los examenes complementarios son normales. Es dificil establecer el diagnostico de la enfermedad de Meniere sin presenciar una crisis. La evolucion es muy variable. Aunque se trata de una enfermedad benigna, puede llegar a ser muy discapacitante. En estos ultimos anos se han hecho grandes progresos en materia de tratamiento. Sin embargo, aunque actualmente es posible controlar y prevenir las crisis de vertigo, en particular mediante la seccion selectiva del nervio vestibular; no siempre se puede predecir la evolucion de la sordera.
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- 2003
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30. Qualité subjective du sommeil des patients appareillés au long cours par ventilation non invasive
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Maxime Patout, Julien Maris, J. Sutter, R. Lukaszewicz, Antoine Cuvelier, A. Portmann, and F. Portier
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Pulmonary and Respiratory Medicine - Abstract
Introduction La qualite du sommeil (QS) subjective chez l’insuffisant respiratoire sous ventilation non invasive (VNI) est mal connue. Notre objectif etait de determiner la prevalence d’une alteration de la QS sous VNI et les facteurs associes a cette derniere. Methodes Etude retrospective monocentrique incluant tous les patients admis en hopital de jour pour reevaluation de leur VNI au CHU de Rouen sur une periode de 3 mois. Une mauvaise QS etait definie par un score de Pittsburgh (PSQI) strictement superieur a 5. Resultats Cent soixante-cinq patients ont ete admis et 127 (77 %) inclus. Parmi les indications de VNI, 25 % des patients presentaient un overlap syndrome, 25 % un syndrome obesite-hypoventilation, 25 % une maladie neuromusculaire, 18 % une BPCO sans syndrome d’apnees du sommeil et 7 % une deformation thoracique. Soixante-quatre patients (50,4 %) avaient une mauvaise QS. En analyse univariee, une mauvaise QS etait plus frequemment associee a la presence d’expectorations (OR = 0,130 [0,035–0,385] [p = 0,00002]), de secheresse buccale (OR = 0,453 [0,208–0,970] [p = 0,033]), d’interruptions nocturnes de la VNI objectivees par le logiciel du ventilateur (p = 0,026), de reveils nocturnes declares (p = 0,0004), de somnolence diurne (OR = 0,397 [0,172–0,888] [p = 0,0166]), de siestes (OR = 0,397 [0,181–0,854] [p = 0,0130]), a la prise de benzodiazepines (OR = 0,289 [0,110–0,712] [p = 0,004]) ou d’antipsychotiques (OR = 0,219 [0,037–0,872] [p = 0,0252]) et au modele du ventilateur (OR = 0,382 [0,173–0,826] [p = 0,012]). En analyse multivariee, une mauvaise QS etait plus frequemment associee a la presence d’expectorations (RR = 4,66 [1,065–20,43] [p = 0,041]), de prise de benzodiazepines (RR = 6,83 [1,525–30,65] [p = 0,012]) et de fuites significatives (RR = 4,52 [1,249–16,39] [p = 0,022]). Il n’y avait pas d’association avec les autres elements fournis par les logiciels des ventilateurs, l’examen clinique, la gazometrie, l’utilisation d’oxygene, les reglages de la VNI, les autres effets indesirables de la VNI ou les evenements intercurrents. Le PSQI etait moderement et inversement correle au score Severe Respiratory Insufficiency (SRI) (r = −0,41, p Conclusion La QS des patients traites par VNI a domicile est frequemment alteree et associee a une alteration significative de la qualite de vie.
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- 2018
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31. Indexing Permafrost Soil Organic Matter Degradation Using High-Resolution Mass Spectrometry
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Taniya Roy Chowdhury, Errol W. Robinson, Baohua Gu, Hongmei Chen, David E. Graham, Stan D. Wullschleger, Nikola Tolić, Evan F. Portier, Stephen J. Callister, Rosalie K. Chu, Liyuan Liang, Benjamin F. Mann, and Elizabeth Herndon
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Permafrost ,lcsh:Medicine ,Soil science ,Mass spectrometry ,Mass Spectrometry ,Carbon cycle ,Soil ,Organic matter ,Microbial biodegradation ,Organic Chemicals ,lcsh:Science ,Van Krevelen diagram ,chemistry.chemical_classification ,Multidisciplinary ,Soil organic matter ,lcsh:R ,Soil chemistry ,Water ,Carbon ,Molecular Weight ,Oxygen ,Biodegradation, Environmental ,chemistry ,Solubility ,Environmental chemistry ,Degradation (geology) ,lcsh:Q ,Hydrogen ,Research Article - Abstract
Microbial degradation of soil organic matter (SOM) is a key process for terrestrial carbon cycling, although the molecular details of these transformations remain unclear. This study reports the application of ultrahigh resolution mass spectrometry to profile the molecular composition of SOM and its degradation during a simulated warming experiment. A soil sample, collected near Barrow, Alaska, USA, was subjected to a 40-day incubation under anoxic conditions and analyzed before and after the incubation to determine changes of SOM composition. A CHO index based on molecular C, H, and O data was utilized to codify SOM components according to their observed degradation potentials. Compounds with a CHO index score between –1 and 0 in a water-soluble fraction (WSF) demonstrated high degradation potential, with a highest shift of CHO index occurred in the N-containing group of compounds, while similar stoichiometries in a base-soluble fraction (BSF) did not. Additionally, compared with the classical H:C vs O:C van Krevelen diagram, CHO index allowed for direct visualization of the distribution of heteroatoms such as N in the identified SOM compounds. We demonstrate that CHO index is useful not only in characterizing arctic SOM at the molecular level but also enabling quantitative description of SOM degradation, thereby facilitating incorporation of the high resolution MS datasets to future mechanistic models of SOM degradation and prediction of greenhouse gas emissions.
- Published
- 2015
32. Endovascular treatment of iliocaval occlusion caused by retroperitoneal fibrosis: Late results in two cases
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P. Di Mauro, F. Portier, Yves S. Alimi, Claude Juhan, and Olivier Hartung
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medicine.medical_specialty ,business.industry ,Vascular disease ,Hemodynamics ,Transluminal Angioplasty ,Retroperitoneal fibrosis ,medicine.disease ,Late results ,Surgery ,Fibrosis ,Occlusion ,medicine ,Radiology ,medicine.symptom ,Endovascular treatment ,business ,Cardiology and Cardiovascular Medicine - Abstract
We report two cases of iliocaval occlusion caused by retroperitoneal fibrosis; one presented acute symptoms and one chronic. Both were treated by use of transluminal angioplasty and stenting with excellent clinical, hemodynamic, and imaging results at 36 and 51 months. These cases confirm the benefit of endovascular techniques in the treatment of nonmalignant obstructive disease of large veins, and specifically in the case of retroperitoneal fibrosis. (J Vasc Surg 2002;36:849-52.)
- Published
- 2002
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33. Spontaneous Intracranial Hypotension: A Rare Cause of Labyrinthine Hydrops
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Patrice Tran Ba Huy, F. Portier, Emmanuel Racy, Philippe Herman, and Carlos de Minteguiaga
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Adult ,Male ,medicine.medical_specialty ,Pathology ,Endolymph ,Intracranial Hypotension ,Perilymph ,03 medical and health sciences ,0302 clinical medicine ,Cerebrospinal fluid ,Internal medicine ,otorhinolaryngologic diseases ,Humans ,Medicine ,Endolymphatic Hydrops ,Endolymphatic hydrops ,Hearing Loss ,030223 otorhinolaryngology ,business.industry ,General Medicine ,medicine.disease ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Otorhinolaryngology ,030220 oncology & carcinogenesis ,Cardiology ,Cochlear aqueduct ,sense organs ,Cerebrospinal fluid pressure ,Unilateral hearing loss ,business - Abstract
Spontaneous intracranial hypotension should be considered as a possible cause of cochlear hydrops. We report a case of unilateral hearing loss attributed to spontaneous intracranial hypotension on the basis of characteristic abnormalities seen on magnetic resonance imaging. The diagnostic gold standards for intracranial hypotension are lumbar measurement of cerebrospinal fluid pressure and magnetic resonance imaging. The usual treatment is an autologous blood injection into the peridural spaces. The mechanism of hearing loss is thought to involve secondary perilymph depression due to a patent cochlear aqueduct. This perilymph depression would induce a compensatory expansion of the endolymphatic compartment, with a subsequent decrease in basilar or Reissner's membrane compliance. Endolymphatic hydrops can occur in the course of intracranial hypotension, and not only because of abnormal endolymph production or resorption. Hydrops can thus be classified into 1) syndromes of endolymphatic origin and 2) syndromes of perilymphatic origin, in which loss of perilymph induces compensatory expansion of the endolymphatic space.
- Published
- 2002
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34. Evidence for expiratory flow limitation of extrathoracic origin in patients with obstructive sleep apnoea
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F. Portier, P Pasquis, Eric Verin, Thomas Similowski, Catherine Tardif, and J.-F. Muir
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Male ,Pulmonary and Respiratory Medicine ,Supine position ,Functional Residual Capacity ,Vital Capacity ,Sitting ,Sleep Apnea Syndromes ,Functional residual capacity ,stomatognathic system ,Forced Expiratory Volume ,medicine ,Humans ,Lung volumes ,Lung Diseases, Obstructive ,Aged ,Sleep disorder ,business.industry ,fungi ,Total Lung Capacity ,Respiratory disease ,respiratory system ,Middle Aged ,medicine.disease ,nervous system diseases ,respiratory tract diseases ,Anesthesia ,Female ,Original Article ,business ,Airway ,Body mass index - Abstract
Background: A study was undertaken to examine the expiratory flow response to a negative pressure (NEP) applied at the airway in patients with no abnormalities of the intrathoracic airway but suffering from the obstructive sleep apnoea syndrome (OSAS). Methods: Nineteen patients with OSAS with normal spirometric values were studied. NEP of –5 cm H2O and –10 cm H2O was applied to the mouth when sitting and when supine. Results: Thirteen patients exhibited expiratory flow limitation when supine (group 1). Of these, three also had flow limitation in the sitting position. The remaining six patients (group 2) had no flow limitation. Patients in groups 1 and 2 were similar with respect to age, sex, and body mass index, but the apnoea/hypopnoea index (AHI) was higher in group 1 than in group 2 (p
- Published
- 2002
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35. A rare clival and sellar fracture with pneumatocephalus
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D. Salvan, Olivier Duruisseau, Patrice Tran Ba Huy, F. Portier, and Philippe Herman
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medicine.medical_specialty ,Fracture site ,Head trauma ,Head Injuries, Closed ,Humans ,Medicine ,Severe osteoporosis ,Sella Turcica ,Aged ,business.industry ,Complex fracture ,General Medicine ,Skull Fracture, Basilar ,Surgery ,Skull ,Epistaxis ,medicine.anatomical_structure ,Otorhinolaryngology ,Pneumocephalus ,Fracture (geology) ,Osteoporosis ,Female ,Tomography, X-Ray Computed ,Low resistance ,business - Abstract
We present a case of clival and sellar complex fracture produced by an indirect mechanism. This previously healthy patient had an occipital trauma followed by epistaxis. CT showed a clival and sellar fracture with pneumatocephalus. The probable fracture mechanism was contre-coup injury, linked to cerebral shock-wave transmission. This type of fracture is generally observed in the anterior part of the skull base, in a low resistance area. Severe osteoporosis probably accounted for the unusual fracture site in this patient. A mechanism of direct clival transmission is discussed, together with the usual complications of sphenoid injuries.
- Published
- 2002
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36. Tratamiento quirúrgico del fibroma nasofaríngeo
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S. Hervé, F. Portier, P. Herman, and P. Tran Ba Huy
- Abstract
Resumen El tratamiento del fibroma nasofaringeo consiste principalmente en su exeresis quirurgica en condiciones de seguridad optimas gracias a la embolizacion preoperatoria, los progresos de la monitorizacion anestesica y la realizacion de autotransfusiones. Esta cirugia tiene como objetivo curar al paciente evitando hasta las mas minimas secuelas (cicatriz antiestetica, anquilosis mandibular, estenosis de las vias lagrimales, deformacion facial, hipoestesia infraorbitaria, trastorno de la articulacion dental e incluso secuelas neurologicas). Segun la extension del tumor, la mayoria de las situaciones se resuelven por via transnasal (con guiado endoscopico) o por via transfacial anterior. Excepcionalmente pueden indicarse la via lateral transcigomatica (en caso de gran extension lateral) o las vias infratemporal o subfrontal (en caso de gran extension intracraneal). Actualmente, los controles postoperatorios se realizan con metodos por imagenes que permiten evaluar la calidad de la exeresis, detectar precozmente las eventuales recidivas y, en algunos casos, estudiar su evolucion.
- Published
- 2002
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37. Stratégie d’exploration d’un adulte polytraumatisé dans le coma
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M. Leone, F. Portier, Kathia Chaumoitre, Jacques Albanèse, C. Martin, and François Antonini
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Injury control ,medicine.diagnostic_test ,Accident prevention ,media_common.quotation_subject ,Multiple injury ,Poison control ,Computed tomography ,General Medicine ,Art ,Wounds nonpenetrating ,Anesthesiology and Pain Medicine ,medicine ,Humanities ,media_common - Abstract
Resume Objectif : Mise au point sur la strategie diagnostique lors de la reception en unite de soins intensifs d’un patient adulte dans le coma victime d’un polytraumatisme ferme. Source de donnees : Recherche sur la base de donnees Pubmed® (721 references) des etudes de langue francaise et anglaise ayant fait l’objet d’une publication entre 1990-2000 et sur des ouvrages specialises sur la prise en charge du traumatisme grave. Quelques etudes anterieures ont ete citees du fait de l’absence de nouvelles donnees sur leur theme. Selection des donnees : Les articles ont ete selectionnes en fonction de leur qualite et leur originalite. Les criteres de selection ont ete bases essentiellement sur la reproductibilite des resultats exposes. Les etudes les plus recentes et les plus representatives ont ete citees. Les mots cles initiaux ont ete : management of multiple trauma. Synthese des donnees : Les premieres heures de prise en charge du traumatise grave sont fondamentales. Il est imperatif d’adresser le patient dans une structure apte a le recevoir. Si l’instabilite hemodynamique predomine, la regulation doit le diriger vers l’hopital le plus proche possedant un bloc operatoire. Des que la stabilite hemodynamique est restauree, il convient d’orienter ce type de patient vers des structures possedant un plateau une technique de haut niveau. La reception d’un polytraumatise necessite une equipe pluridisciplinaire composee d’un anesthesiste-reanimateur, d’un chirurgien visceral, d’un neurochirurgien, d’un chirurgien orthopediste et d’un radiologue, agissant selon des protocoles conjointement rediges. Le bilan lesionnel a entreprendre doit avoir deux proprietes : qualite des examens obtenus et rapidite de realisation. La tomodensitometrie du corps entier, « plus grand denominateur commun » pour l’exploration de l’ensemble des appareils, repond a de telles exigences.
- Published
- 2002
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38. Respiratory obstruction as a sign of brainstem dysfunction in infants with Chiari malformations
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M.-P. Morisseau-Durand, Yves Manach, Michel Zerah, Rémi Marianowski, and F. Portier
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Male ,Larynx ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,Severity of Illness Index ,medicine ,Humans ,Laryngomalacia ,Vocal cord paralysis ,Chiari malformation ,business.industry ,Infant, Newborn ,Vagus Nerve ,General Medicine ,Airway obstruction ,medicine.disease ,Laryngeal Obstruction ,Arnold-Chiari Malformation ,Hydrocephalus ,Surgery ,Airway Obstruction ,medicine.anatomical_structure ,Otorhinolaryngology ,Anesthesia ,Pediatrics, Perinatology and Child Health ,Failure to thrive ,Gastroesophageal Reflux ,Female ,medicine.symptom ,Deglutition Disorders ,business ,Brain Stem - Abstract
Laryngeal respiratory obstruction associated with Chiari malformations was first described in 1932. We studied this type of obstruction in six children with one or several disorders pointing to brainstem dysfunction (failure to thrive, velopharyngeal incompetence, gastroesophageal reflux, or vagal hypertonia). The nature of the laryngeal obstruction was highly variable (vocal cord paralysis, paradoxical vocal cord motion, laryngomalacia) as were the frequency and severity of associated disorders. Chiari malformations should be routinely sought in a child with laryngeal respiratory obstruction occurring at birth or later, whatever the endoscopic diagnosis, especially when signs of brainstem dysfunction are present. The best tool for diagnosing the Chiari malformation is T1- and T2-weighted MRI. Signs of brainstem dysfunction must be treated symptomatically, before treating Chiari malformations by decompressive surgery. This latter approach led to full functional recovery in all five children who underwent the procedure. Palliative surgical treatment should be reserved for patients in whom this procedure is unsuccessful.
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- 2001
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39. [Untitled]
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A. Maucherat, B. Vandame, A. Bijaoui, F. Portier-Fozzani, and Eit Team
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Physics ,business.industry ,Astronomy and Astrophysics ,Galaxy ,Wavelet ,Space and Planetary Science ,Histogram ,Physics::Space Physics ,Wide dynamic range ,Coronal mass ejection ,Calibration ,Astrophysics::Solar and Stellar Astrophysics ,Computer vision ,Artificial intelligence ,Noise (video) ,Zoom ,business ,Remote sensing - Abstract
The large dynamic range provided by the SOHO/EIT CCD (1 : 5000) is needed to observe the large EUV zoom of coronal structures from coronal homes up to flares. Histograms show that often a wide dynamic range is present in each image. Extracting hidden structures in the background level requires specific techniques such as the use of the Multiscale Vision Model (MVM, Bijaoui et al., 1998). This method, based on wavelet transformations optimizes detection of various size objects, however complex they may be. Bijaoui et al. built the Multiscale Vision Model to extract small dynamical structures from noise, mainly for studying galaxies. In this paper, we describe requirements for the use of this method with SOHO/EIT images (calibration, size of the image, dynamics of the subimage, etc.). Two different areas were studied revealing hidden structures: (1) classical coronal mass ejection (CME) formation and (2) a complex group of active regions with its evolution. The aim of this paper is to define carefully the constraints for this new method of imaging the solar corona with SOHO/EIT. Physical analysis derived from multi-wavelength observations will later complete these first results.
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- 2001
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40. Fibroma nasofaríngeo
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S. Hervé, F. Portier, R. Chapot, J.P. Guichard, M. Wassef, P. Tran Ba Huy, and P. Herman
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- 2001
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41. Serous or mucoid effusion in the course of secretory otitis media: influence of ion transport modulation
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P. Herman, F. Portier, P. Tran Ba Huy, and Wei-Chung Hsu
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Pathology ,medicine.medical_specialty ,Ear, Middle ,Inflammation ,Cell Line ,medicine ,Humans ,Ion transporter ,Ion Transport ,Otitis Media with Effusion ,Viscosity ,business.industry ,Mucin ,Mucins ,Exudates and Transudates ,Hydrogen Peroxide ,General Medicine ,Epithelium ,Serous fluid ,medicine.anatomical_structure ,Otitis ,Otorhinolaryngology ,Effusion ,Chronic Disease ,Anti-Infective Agents, Local ,Middle ear ,Surgery ,medicine.symptom ,business - Abstract
Objective: Secretory otitis media is defined by a chronic effusion in the middle ear cavities, behind an intact tympanic membrane without acute infection. In the course of secretory otitis media, the effusion is sometimes thick (or mucoid) and other times thin (or serous). For several authors, these differences might be related to different inflammatory levels rather than to distinct pathophysiological mechanisms. The purpose of this study was to determine whether the modulation of ion transport by inflammation could account for the differences observed in the aspect of ME effusion. Methods: Hydrogen peroxide (H2O2), used as an inflammation model was tested on a middle ear cell line (MESV) in culture. Results: Results show that low and high concentrations of H2O2 have opposite effects on ion (and then water) absorption by the middle ear epithelium. Conclusion: the modulation of ion and water absorption by inflammation could modify the mucins concentration in the effusion, and explain observed viscosity differences in the course of secretory otitis media.
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- 2001
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42. [Untitled]
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W. Neupert, Pascal Démoulin, Markus J. Aschwanden, F. Portier-Fozzani, and Jean-Pierre Delaboudiniere
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Loop (topology) ,Physics ,Flux tube ,Space and Planetary Science ,Magnetic helicity ,Extreme ultraviolet ,Coronal plane ,Astrophysics::Solar and Stellar Astrophysics ,Flux ,Astronomy and Astrophysics ,Astrophysics ,Coronal loop ,Twist - Abstract
Emerging coronal loops were studied with extreme ultraviolet observations performed by SOHO/EIT on 5 and 6 August 1997 for NOAA 8069. Physical parameters (size and twist) were determined by a new stereoscopic method. The flux tubes were measured twisted when first observed by EIT. After emerging, they de-twisted as they expanded, which corresponds to a minimization of the energy. Different scenarios which take into account the conservation of the magnetic helicity are discussed in relation with structure and temperature variations.
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- 2001
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43. Evaluation of Home versus Laboratory Polysomnography in the Diagnosis of Sleep Apnea Syndrome
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Antoine Cuvelier, F. Portier, Adriana Portmann, Jean François Muir, Etienne Devin, Lionel Vascaut, Pierre Czernichow, and D. Benhamou
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Adult ,Male ,Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Electrodiagnosis ,Polysomnography ,Quality of sleep ,Monitoring, Ambulatory ,Critical Care and Intensive Care Medicine ,Poor quality ,Sleep Apnea Syndromes ,Respiratory disturbance index ,Humans ,Medicine ,Subjective quality ,medicine.diagnostic_test ,business.industry ,Airway Resistance ,Sleep apnea ,Equipment Design ,Middle Aged ,medicine.disease ,Anesthesia ,Physical therapy ,Feasibility Studies ,Female ,business - Abstract
The aim of this study was to compare home polysomnography (HoPSG) with laboratory polysomnography (LabPSG) in the diagnosis of sleep apnea syndrome (SAS). A total of 103 patients referred for investigation of SAS underwent two full polysomnographies, using the portable Minisomno device at home and the Respisomnographe in the laboratory (both devices manufactured by the same company). Twenty percent of home-studied device polysomnography (HoSD-PSG) recordings and 5% of LabPSG recordings were excluded from analysis either because of lost data or poor quality data. Sleep stage distribution and subjective quality of sleep were similar by both methods. Using LabPSG, the mean (+/- SD) RDI was 25.7 (+/- 30.6) versus 22.8 (+/- 31.5) using HoSD-PSG (p > 0.05). Absolute differences between the home and laboratory respiratory disturbance index (RDI) were less than 10 for 65% of patients. Discordant RDIs (i.e., differences greater than 10) were observed for 63% of individuals with severe SAS (RDI > 30) versus 22% of those with normal or moderate SAS (RDI
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- 2000
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44. Comparison of 87 GHz solar polar structures with EUV and soft X-ray emission
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Silja Pohjolainen, D. Ragaigne, and F. Portier-Fozzani
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Solar minimum ,Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Extreme ultraviolet lithography ,General Physics and Astronomy ,Astronomy ,Coronal hole ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Coronal loop ,Coronal radiative losses ,Intensity (physics) ,Physics::Space Physics ,Astrophysics::Solar and Stellar Astrophysics ,Polar ,Millimeter ,Astrophysics::Galaxy Astrophysics - Abstract
Polar radio brightenings at 87 GHz (3.5 mm) are compared for the rst time with features seen in EUV and soft X-rays. The data consist of nearly simultane- ous full disk images and maps from Metsahovi Radio Observatory, SOHO/EIT, and Yohkoh/SXT on 9 selected days near the solar minimum (1996-1997). The observed radio brightenings corresponded to var- ious features seen in EUV, such as diuse or localized intensity enhancements (e.g., bright points and bases of polar plumes), and intensity depressions of varying sizes (e.g., coronal holes). Some of these features were also vis- ible in soft X-rays. The visibility of radio bright coronal holes seemed to depend on how much of the polar area was exposed, due to the variation of the B0-angle. The observed radio depressions near the solar poles were very well correlated with coronal holes and other EUV and/or soft X-ray intensity drops. More than half of the coronal holes, or coronal hole-like intensity drops in EUV and soft X-rays, had radio brightenings inside them. Therefore coronal holes do not have uniform radio bright- ness at 87 GHz. Many of the bright points seen at lower latitudes in the EIT and SXT images had no, or just faint, counterparts in the millimeter radio maps. It appears that for an EUV bright point to show up at 87 GHz it has to be bright and/or spatially large also in soft X-rays.
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- 2000
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45. Dynamic Anal Endosonography May Challenge Defecography for Assessing Dynamic Anorectal Disorders: Results of a Prospective Pilot Study
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D. Houtin, L Heyries, J. Salducci, Marc Barthet, N Barriere, Michel Bouvier, P Orsoni, F. Portier, Jean-Charles Grimaud, and P. Mambrini
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Adult ,medicine.medical_specialty ,Constipation ,Pilot Projects ,Rectal diseases ,Sensitivity and Specificity ,Endosonography ,Process dynamics ,Predictive Value of Tests ,medicine ,Humans ,Defecography ,Prospective Studies ,Defecation ,Aged ,Gynecology ,Anus Diseases ,medicine.diagnostic_test ,business.industry ,Gastroenterology ,Middle Aged ,Surgery ,Rectal Diseases ,Female ,medicine.symptom ,Anal sphincter ,business - Abstract
Buts de l'Etude: Le diagnostic morphologique des troubles de la statique rectale et de 1 insuffisance perineale repose actuellement sur la defecographie. Nous avons developpe une nouvelle technique d echographie endoanale (EE) dynamique dont nous avons compare les resultats a la defecographie dans une etude prospective aveugle. Patients et Methodes: Nous avons etudie 43 patients qui presentaient une constipation d'allure terminale, d'âge moyen 51 ans, dont 19 (44%) presentaient une incontinence urinaire d'effort. L'EE etait realisee a l'aide d'une sonde lineaire de 7,5 MHz (Toshiba, Tokyo, Japon), avec un enregistrement au repos et en poussee. Une manometrie anorectale et une defecographie etaient realisees, aucun des operateurs n'etant informes des differents resultats. Resultats: La defecographie a diagnostique une descente perineale chez 29 patients (68 %), une rectocele chez 25 patients (58 %), et une procidence rectale interne chez 8 patients (18%). La concordance entre descente du col vesical (EE dynamique) et descente perineale (defecographie) etait de 35/43 patients (80%), entre descente du plan des releveurs (EE dynamique) et descente perineale (defecographie) etait de 40/43 patients (93 %), entre rectocele en EE dynamique et en defecographie etait de 27/43 patients (57%), entre procidence muqueuse interne en EE dynamique et en defecographie etait de 34/43 patients (80%). L'adjonction de 50 ml d'eau dans le rectum realisee chez les 15 derniers patients a permis de faire passer la sensibilite de l'EE dynamique pour le diagnostic de rectocele de 36 a 86% et la precision diagnostique de 57 a 87%, Conclusions: L'EE dynamique semble etre un examen fiable pour deceler une insuffisance perineale mais egalement pour diagnostiquer une rectocele ou une procidence rectale interne. L'EE dynamique pourrait remplacer la defecographie dans la mesure ou elle permet en plus une evaluation de l'etat sphincterien anal et evite une irradiation perineale.
- Published
- 2000
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46. Embriología del oído interno
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Rémi Marianowski, T. Van Den Abbeele, F. Portier, H. Copin, P. Tran Ba Huy, and P. Herman
- Abstract
Resumen La embriologia del oido interno ha progresado recientemente gracias a la microscopia electronica de barrido y al desarrollo de la biologia molecular que permite el estudio de las citocinas. El laberinto membranoso deriva de la placoda auditiva, engrosamiento del ectoblasto que aparece al 23o dia. La placoda se invagina durante la quinta semana para formar el otocisto que toma una forma bilobulada: la parte dorsal formara el vestibulo y la porcion ventral, el conducto coclear. Un grupo de celulas se desprende de la placoda auditiva para formar el ganglio estatoacustico, cuya porcion ventral se adosa al conducto coclear y sigue su enrollamiento, transformandose en el ganglio espiral. La primera vuelta de espira de la coclea se forma a las 7 semanas y las dos vueltas y media se completan a las 9 semanas. En esta fase, la coclea mide 3 mm de la base al apex; aumentara de tamano hasta el quinto mes, cuando alcanza su tamano adulto. Los espacios perilinfaticos se forman dentro del mesenquima que rodea al canal coclear hacia la 11a semana y la osificacion del laberinto oseo se produce del quinto mes al nacimiento. La coclea es funcional desde el quinto mes, mientras que la diferenciacion celular aun es incompleta. La formacion del tunel de Corti y de los espacios de Nuel se continua hasta el octavo mes. El BDNF (brain-derived neurotrophic factor) y la NT-3 (neurotrophin-3) desempenan un papel decisivo en el desarrollo de las conexiones nerviosas del oido interno. Por ultimo, es probable que en las interacciones entre celulas epiteliales y celulas mesenquimatosas intervengan otras citocinas.
- Published
- 2000
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47. Three‐dimensional Stereoscopic Analysis of Solar Active Region Loops. I.SOHO/EIT Observations at Temperatures of (1.0–1.5) x 106K
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Jeffrey Newmark, James A. Klimchuk, Markus J. Aschwanden, F. Portier-Fozzani, Arik Zucker, Werner M. Neupert, Jean-Pierre Delaboudiniere, and G. Allen Gary
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Physics ,Loop (topology) ,Electron density ,Orders of magnitude (time) ,Space and Planetary Science ,Radiative transfer ,Plasma parameter ,Electron temperature ,Astronomy and Astrophysics ,Scale height ,Astrophysics ,Computational physics ,Magnetic field - Abstract
The three-dimensional structure of solar active region NOAA 7986 observed on 1996 August 30 with the Extreme-Ultraviolet Imaging Telescope (EIT) on board the Solar and Heliospheric Observatory (SOHO) is analyzed. We develop a new method of dynamic stereoscopy to reconstruct the three-dimensional geometry of dynamically changing loops, which allows us to determine the orientation of the mean loop plane with respect to the line of sight, a prerequisite to correct properly for projection effects in three-dimensional loop models. With this method and the filter-ratio technique applied to EIT 171 and 195 A images we determine the three-dimensional coordinates [x(s), y(s), z(s)], the loop width w(s), the electron density ne(s), and the electron temperature Te(s) as a function of the loop length s for 30 loop segments. Fitting the loop densities with an exponential density model ne(h) we find that the mean of inferred scale height temperatures, Tλe=1.22 ± 0.23 MK, matches closely that of EIT filter-ratio temperatures, TEITe=1.21 ± 0.06 MK. We conclude that these cool and rather large-scale loops (with heights of h≈30-225 Mm) are in hydrostatic equilibrium. Most of the loops show no significant thickness variation w(s), but we measure for most of them a positive temperature gradient (dT/ds>0) across the first scale height above the footpoint. Based on these temperature gradients we find that the conductive loss rate is about 2 orders of magnitude smaller than the radiative loss rate, which is in strong contrast to hot active region loops seen in soft X-rays. We infer a mean radiative loss time of τrad≈40 minutes at the loop base. Because thermal conduction is negligible in these cool EUV loops, they are not in steady state, and radiative loss has entirely to be balanced by the heating function. A statistical heating model with recurrent heating events distributed along the entire loop can explain the observed temperature gradients if the mean recurrence time is 10 minutes. We computed also a potential field model (from SOHO/MDI magnetograms) and found a reasonable match with the traced EIT loops. With the magnetic field model we determined also the height dependence of the magnetic field B(h), the plasma parameter β(h), and the Alfven velocity vA(h). No correlation was found between the heating rate requirement EH0 and the magnetic field Bfoot at the loop footpoints.
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- 1999
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48. Ventilation non invasive (VNI) à domicile : mise en place, paramètres et devenir des patients
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Joerg Steier, Luis-Carlos Molano, Nicholas Hart, D. Benhamou, N. Grey, Catherine Viacroze, A. Benattia, Antoine Cuvelier, E. Lhuillier, F. Portier, J.-F. Muir, Maxime Patout, Bouchra Lamia, G. Arbane, P. Marino, Patrick B. Murphy, J. Dupuis, and Mike Mackie
- Subjects
Pulmonary and Respiratory Medicine - Abstract
Introduction La pratique de la ventilation non invasive (VNI) a domicile pour le traitement de l’insuffisance respiratoire chronique varie selon les centres. L’objectif de cette etude etait de decrire les modalites d’initiation et le devenir des patients au sein de deux centres experts europeens. Methodes Etude retrospective utilisant les bases de donnees prospectives des patients appareilles par VNI a domicile au sein de la Lane Fox Respiratory Unit (LFU) a Londres et du service de pneumologie du CHU de Rouen entre le 1er janvier 2008 et le 31 decembre 2014. Resultats Mille sept cent quarante-six patients ont ete appareilles par VNI a deux niveaux de pression. Parmi les patients, 29,5 % (n = 515) etaient atteints d’un syndrome obesite-hypoventilation, 22,8 % (n = 398) d’une pathologie neuromusculaire, 19,1 % (n = 334) d’une BPCO, 12,6 % (n = 221) d’une BPCO associee a un syndrome d’apnee du sommeil (SAOS), 10,6 % (n = 184) d’un SAOS et 5,4 % (n = 94) d’une pathologie de la paroi thoracique. La VNI etait initiee a la suite d’un episode aigu de maniere plus frequente a Rouen (59 %) comparativement a Londres (39 %) (p Fig. 1 ). Les patients atteints de BPCO + SAOS avaient une survie significativement superieure a ceux avec BPCO. Conclusion Les reglages de la VNI et le moment de l’appareillage varient significativement selon le centre d’appareillage. Les patients appareilles par VNI et atteints de BPCO ou d’une pathologie neuromusculaire ont le pronostic le plus sombre. Les patients associant BPCO et SAOS constituent un groupe avec certaines caracteristiques propres.
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- 2016
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49. [Untitled]
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A. Maucherat, P. Cugnon, Jeffrey S. Newmark, Claude Jamar, F. Clette, Robert A. Stern, W. M. Neupert, James R. Lemen, John D. Moses, G. E. Artzner, Russell A. Howard, R. C. Catura, Barbara J. Thompson, Jean-Pierre Delaboudiniere, Jean-Marc Defise, F. Portier-Fozzani, Pierre Rochus, Alan H. Gabriel, D. J. Michels, Joseph B. Gurman, Samuel L. Freeland, and Kenneth P. Dere
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Physics ,Electron density ,Space and Planetary Science ,Thermal ,Energy balance ,Radiative transfer ,Coronal hole ,Astronomy and Astrophysics ,Astrophysics ,Helmet streamer ,Atmospheric temperature range ,Thermal conduction - Abstract
Solar EUV images recorded by the EUV Imaging Telescope (EIT) on SOHO have been used to evaluate temperature and density as a function of position in two largescale features in the corona observed in the temperature range of 1.0–2.0 MK. Such observations permit estimates of longitudinal temperature gradients (if present) in the corona and, consequently, estimates of thermal conduction and radiative losses as a function of position in the features. We examine two relatively cool features as recorded in EIT's Fe ix/x (171 A) and Fe xii (195 A) bands in a decaying active region. The first is a long-lived loop-like feature with one leg, ending in the active region, much more prominent than one or more distant footpoints assumed to be rooted in regions of weakly enhanced field. The other is a near-radial feature, observed at the West limb, which may be either the base of a very high loop or the base of a helmet streamer. We evaluate energy requirements to support a steady-state energy balance in these features and find in both instances that downward thermal conductive losses (at heights above the transition region) are inadequate to support local radiative losses, which are the predominant loss mechanism. The requirement that a coronal energy deposition rate proportional to the square of the ambient electron density (or pressure) is present in these cool coronal features provides an additional constraint on coronal heating mechanisms.
- Published
- 1998
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50. First Year of Observations with SOHO/EIT of the 'Quiet' Sun Corona
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A. Maucherat, F. Portier-Fozzani, and Eit Team
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Physics ,QUIET ,Astronomy - Abstract
Since January 1996 (EIT first light) the Extreme Ultraviolet Telescope aboard SOHO has produced about 20,000 wide-field images of the corona and transition regions. Four different emission lines (He II, Fe IX/X, Fe XII, Fe XV) were selected to detail morphologies of magnetic structures in the corona. They show the different structures present in the corona with information about their topologies (Neupert et al. 1998). They provide the global temperature distribution in the quiet corona in the range 0.5 to 3 × 106 K.The evolution of the corona during the first year of the SOHO mission revealed its nonuniform aspect and the nonregularity of the appearance of new active regions. Changes observed in active regions and coronal holes (e.g., August–September 1996) showed the complex role of magnetic fields including magnetic interactions and possible reconnections needed to explain some loop morphology evolution.
- Published
- 1998
- Full Text
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