Search for the standard model Higgs boson decaying to W + W − in the fully leptonic final state i... more Search for the standard model Higgs boson decaying to W + W − in the fully leptonic final state in pp collisions at √ s = 7 TeV
A search for the standard model Higgs boson decaying into two Z bosons with subsequent decay into... more A search for the standard model Higgs boson decaying into two Z bosons with subsequent decay into a final state containing two quark jets and two leptons, H → ZZ ( * ) → qq − + is presented. Results are based on data corresponding to an integrated luminosity of 4.6 fb −1 of proton-proton collisions at √ s = 7 TeV, collected with the CMS detector at the LHC. In order to discriminate between signal and background events, kinematic and topological quantities, including the angular spin correlations of the decay products, are employed. Events are further classified according to the probability of the jets to originate from quarks of light or heavy flavor or from gluons. No evidence for the Higgs boson is found, and upper limits on its production cross section are determined for a Higgs boson of mass between 130 and 600 GeV.
Yields of prompt and non-prompt J/ψ, as well as Υ(1S) mesons, are measured by the CMS experiment ... more Yields of prompt and non-prompt J/ψ, as well as Υ(1S) mesons, are measured by the CMS experiment via their µ + µ − decays in PbPb and pp collisions at √ s NN = 2.76 TeV for quarkonium rapidity |y| < 2.4. Differential cross sections and nuclear modification factors are reported as functions of y and transverse momentum p T , as well as collision centrality. For prompt J/ψ with relatively high p T (6.5 < p T < 30 GeV/c), a strong, centrality-dependent suppression is observed in PbPb collisions, compared to the yield in pp collisions scaled by the number of inelastic nucleon-nucleon collisions.
Search for the standard model Higgs boson in the H → ZZ → 2 2ν channel in pp collisions at √ s = ... more Search for the standard model Higgs boson in the H → ZZ → 2 2ν channel in pp collisions at √ s = 7 TeV
A new modeling methodology that enables represent the urban traffic system (UTS) dynamic entities... more A new modeling methodology that enables represent the urban traffic system (UTS) dynamic entities using a multi-agent event oriented approach is presented. The methodology uses an enhanced n-Level net system (n-LNS) formalism of Petri nets. The first level describes the traffic network and UTS static and dynamic information objects; the second level describes the general entity behavior (activity execution, decision-making, entity interaction); finally at third level, particular entity behavior (process, skills and activities) incorporating a decision-making mechanism is described. The suggested novel methodology presented in this paper enable integrating formally diverse UTS dynamic entities behaviors in an event and multi-agent oriented approach.
We have characterized a temperate phage (MM1) from a clinical isolate of the multiply antibiotic-... more We have characterized a temperate phage (MM1) from a clinical isolate of the multiply antibiotic-resistant Spanish/American 23F Streptococcus pneumoniae clone (Spain 23F -1 strain). The 40-kb double-stranded genome of MM1 has been isolated as a DNA-protein complex. The use of MM1 DNA as a probe revealed that the phage genome is integrated in the host chromosome. The host and phage attachment sites, attB and attP, respectively, have been determined. Nucleotide sequencing of the attachment sites identified a 15-bp core site (5-TTATA ATTCATCCGC-3) that has not been found in any bacterial genome described so far. Sequence information revealed the presence of an integrase gene (int), which represents the first identification of an integrase in the pneumococcal system. A 1.5-kb DNA fragment embracing attP and the int gene contained all of the genetic information needed for stable integration of a nonreplicative plasmid into the attB site of a pneumococcal strain. This vector will facilitate the introduction of foreign genes into the pneumococcal chromosome. Interestingly, DNAs highly similar to that of MM1 have been detected in several clinical pneumococcal isolates of different capsular types, suggesting a widespread distribution of these phages in relevant pathogenic strains.
In order to better understand the mechanisms of action of a monoclonal anti-CD4/BF5 antibody(mAb)... more In order to better understand the mechanisms of action of a monoclonal anti-CD4/BF5 antibody(mAb), cytokine secretions were studied in 14 multiple sclerosis (MS) patients treated in a phase 1 trial. Secretion patterns of IFNgamma, IL2, IL4, IL10 and TNFalpha by peripheral blood mononuclear cells were studied before (DO) and after (D30) the treatment. We decided to undertake this study because in a previous one we observed no variations in serum levels of TNFalpha, IFNgamma, IL1, IL6. Results showed significant reductions in IFNgamma, IL2 and TNFalpha secretions after treatment. The anti-CD4 mAb seemed to act on both Th1- and Th2-cells but with preferential action on Th1-cells. Results on Th2-cells were less obvious even though a significant decrease in IL10 was observed. There was no correlation between any of the immunological markers studied and disease activity. This study demonstrates that pharmacological modifications of the CD4 receptor can induce variations in several cytokine secretion levels. It also stresses the role played by Th1- and Th2-cells in the etiopathogenesis of MS.
Exposure of newborn rats to hyperoxia impairs alveolarization. Nitric oxide (NO) may prevent this... more Exposure of newborn rats to hyperoxia impairs alveolarization. Nitric oxide (NO) may prevent this evolution. Angiogenesis and factors involved in this process, but also other growth factors (GFs) involved in alveolar development, are likely potential therapeutic targets for NO. We studied the effects of the NO donor, [Z]-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)aminio]diazen-1-ium-1, 2-diolate, also termed DETANONOate (D-NO), on hyperoxia-induced changes in key regulatory factors of alveolar development in neonatal rats, and its possible preventive effect on the physiologic consequences of hyperoxia. Newborn rat pups were randomized at birth to hyperoxia (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 95% O2) or room air exposure for 6 or 10 d, while receiving D-NO or its diluent. On Day 6, several GFs and their receptors were studied at pre- and/or post-translational levels. Elastin transcript determination on Day 6, and elastin deposition in tissue and morphometric analysis of the lungs on Day 10, were also performed. Hyperoxia decreased the expression of vascular endothelial growth factor (VEGF) receptor (VEGFR) 2, fibroblast growth factor (FGF)-18, and FGF receptors (FGFRs) FGFR3 and FGFR4, increased mortality, and impaired alveolarization and capillary growth. D-NO treatment of hyperoxia-exposed pups restored the expression level of FGF18 and FGFR4, induced an increase of both VEGF mRNA and protein, enhanced elastin expression, and partially restored elastin deposition in alveolar walls. Although, under the present conditions, D-NO failed to prevent the physiologic consequences of hyperoxia in terms of survival and lung alveolarization, our findings demonstrate molecular effects of NO on GFs involved in alveolar development that may have contributed to the protective effects previously reported for NO.
Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte... more Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte influx in airspaces, and impaired alveolarization. Inhibitors of type 4 phosphodiesterases are potent anti-inflammatory drugs now proposed for lung disorders. The current study was undertaken to determine the effects of the prototypal phosphodiesterase-4 inhibitor rolipram on alveolar development and on hyperoxia-induced lung injury.
Capnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reporte... more Capnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported.
Odile Launay, groupe hospitalier Cochin-Broca-Hôtel-Dieu, centre d'investigation clinique de vacc... more Odile Launay, groupe hospitalier Cochin-Broca-Hôtel-Dieu, centre d'investigation clinique de vaccinologie Cochin-Pasteur, 27, rue du Faubourg Saint-Jacques,
To assess neonatal morbidity in twin pregnancy according to the planned mode of delivery. A retro... more To assess neonatal morbidity in twin pregnancy according to the planned mode of delivery. A retrospective cohort study of 758 consecutive sets of twins born after 35 weeks of gestation with a cephalic-presenting first twin was undertaken in a level III maternity unit in which active management of the second twin delivery is performed routinely. The primary outcome was a composite measure of neonatal mortality and morbidity, including pH less than 7.0, 5-minute Apgar score less than 4, neonatal intensive care unit transfer more than 4 days, pneumothorax, and fracture. Control for potential confounders was performed by excluding from the analysis women who experienced pregnancy complications and by using logistic regression models. Vaginal or cesarean delivery was planned for 657 (86.7%) and 101 (13.3%) women, respectively. Among planned vaginal deliveries, 515 (78.4%) patients delivered both twins vaginally, 139 (21.1%) had a cesarean delivery during labor, and 3 (0.5%) had cesarean delivery for the second twin. After vaginal birth of the first twin, the mean intertwin delivery interval was 4.9+/-3.2 minutes. When patients who experienced pregnancy complications were excluded (n=202), the neonatal composite morbidity for the second twin did not differ between planned cesarean and planned vaginal delivery (5.0% compared with 4.7%, adjusted odds ratio 1.5, 95% confidence interval 0.3-7.4, P=.63). Neonatal composite morbidity of first twins did not differ between groups. For twin gestations with a cephalic-presenting first twin, planned vaginal delivery after 35 weeks of gestation in selected women remains a safe option in centers used to active management of the second twin delivery.
Clin Microbiol Infect 2010; 16: 1539–1543Clin Microbiol Infect 2010; 16: 1539–1543AbstractCapnocy... more Clin Microbiol Infect 2010; 16: 1539–1543Clin Microbiol Infect 2010; 16: 1539–1543AbstractCapnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported.Capnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported.
Les apnées du prématuré constituent encore actuellement un problème clinique majeur, imposant des... more Les apnées du prématuré constituent encore actuellement un problème clinique majeur, imposant des choix thérapeutiques parfois difficiles. Des apnées plus ou moins longues surviennent chez presque tous les grands prématurés, témoignant d'une instabilité de la régulation respiratoire en rapport avec l'immaturité. Au rôle causal de celle-ci peut toutefois s'ajouter celui de nombreuses pathologies néonatales, qui peuvent aussi contribuer à la survenue d'apnées et doivent être recherchées et traitées. Les apnées du prématuré de courte durée (moins de dix secondes, sans hypoxémie ou bradycardie associée) peuvent être considérées comme sans risque pour l'enfant. Les apnées plus longues entraînent une hypoxémie et un ralentissement de la fréquence cardiaque et des perturbations de l'hémodynamique et de l'oxygénation cérébrales, susceptibles d'entraîner des effets délétères pour le développement à long terme. L'évaluation de leur degré de gravité immédiate et de leurs risques à long terme demeure imprécise. Les décisions thérapeutiques ne peuvent s'appuyer que sur assez peu de données scientifiques. Le citrate de caféine est un traitement efficace des apnées du prématuré, largement utilisé depuis des décennies. Mais c'est seulement très récemment qu'une évaluation rigoureuse de ses bénéfices et de ses inconvénients a été menée. Elle a mis en évidence la faible toxicité du citrate de caféine, et des bénéfices inattendus chez les enfants traités : diminution de fréquence des dysplasies bronchopulmonaires, de la persistance du canal artériel, et, à 18 mois, diminution du taux d'infirmité motrice cérébrale. La pression expiratoire positive par voie nasale, traitement également efficace des apnées, peut être utilisée en cas d'échec ou d'insuffisance du traitement par caféine et en association avec lui. ß 2009 Publié par Elsevier Masson SAS.
Genetic characterization of non-K1 Escherichia coli strains isolated from a mother and her neonat... more Genetic characterization of non-K1 Escherichia coli strains isolated from a mother and her neonate allowed us to provide evidence of the maternal origin of a late-onset neonatal infection. The use of ante- and peripartum antimicrobial prophylaxis with amoxicillin may have promoted the vertical transmission of this amoxicillin-resistant E. coli from mother to newborn. It allowed us to clarify the natural history of the disease.
Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte... more Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte influx in airspaces, and impaired alveolarization. Inhibitors of type 4 phosphodiesterases are potent anti-inflammatory drugs now proposed for lung disorders. The current study was undertaken to determine the effects of the prototypal phosphodiesterase-4 inhibitor rolipram on alveolar development and on hyperoxia-induced lung injury.
Background Monitoring CO2 levels in preterm infants receiving mechanical ventilation is designed ... more Background Monitoring CO2 levels in preterm infants receiving mechanical ventilation is designed to avoid the harmful consequences of hypocapnia or hypercapnia. Capnography is of questionable accuracy for monitoring PCO2 in preterm infants. Objectives To determine the accuracy of sidestream capnography in ventilated preterm infants by comparing end-tidal carbon dioxide (EtCO2) values to mixed venous carbon dioxide pressure (PvCO2) and to transcutaneous carbon dioxide pressure (TcPCO2). Methods Simultaneous recordings of EtCO2, TcPCO2 and PvCO2 in 37 ventilated preterm infants. The PvCO2–EtCO2 gradient was calculated. The Bland–Altman technique and the intra-class correlation coefficient (ICC) were used to assess agreement between methods. The area under the curve (AUC) was calculated. Results Ninety-nine EtCO2/PvCO2 pairs were studied from 37 preterm infants with a mean gestational age of 27.7 ± 1.9 weeks and a mean birth weight of 1,003 ± 331 g. The mean PvCO2–EtCO2 gradient was 11.2 ± 8.0 mmHg, and the ICC was 0.28. The mean PvCO2–TcPCO2 gradient was 0 ± 7.8 mmHg, and the ICC was 0.78. AUCs for EtCO2 and TcPCO2 were similar in detecting high or low PvCO2. Conclusion Despite an insufficient correlation between EtCO2 and PvCO2, capnography was able to detect low and high CO2 warning levels with a similar efficacy to that of TcPCO2, and may therefore be of clinical interest.
The application of multi-disciplinary automotive technologies to hybrid vehicles has resulted in ... more The application of multi-disciplinary automotive technologies to hybrid vehicles has resulted in the integration of alternative propulsion sources and drive-by-wire components for enhanced ground vehicle performance, fuel economy, and occupant safety. The integration of steer-by-wire systems in vehicles facilitates autonomous and semi-autonomous operations, better lateral vehicle behavior, an adjustable steering "feel," and elimination of problems arising due to potential engine cycling. In this paper, a continuous time-varying tracking controller is designed for the vehicle's position/orientation using a simplified vehicle description and reference model for tracking. The tracking error is globally, exponentially forced to a neighborhood of about zero by transforming the system into a flat input-state system and then fusing a filtered tracking error transformation with the dynamic oscillator design. Mathematical models are presented for a steerby-wire rack and pinion unit, vehicle chassis, and tire/road interface dynamics. Representative numerical results are discussed to demonstrate the vehicle's transient response for a prescribed trajectory profile.
Search for the standard model Higgs boson decaying to W + W − in the fully leptonic final state i... more Search for the standard model Higgs boson decaying to W + W − in the fully leptonic final state in pp collisions at √ s = 7 TeV
A search for the standard model Higgs boson decaying into two Z bosons with subsequent decay into... more A search for the standard model Higgs boson decaying into two Z bosons with subsequent decay into a final state containing two quark jets and two leptons, H → ZZ ( * ) → qq − + is presented. Results are based on data corresponding to an integrated luminosity of 4.6 fb −1 of proton-proton collisions at √ s = 7 TeV, collected with the CMS detector at the LHC. In order to discriminate between signal and background events, kinematic and topological quantities, including the angular spin correlations of the decay products, are employed. Events are further classified according to the probability of the jets to originate from quarks of light or heavy flavor or from gluons. No evidence for the Higgs boson is found, and upper limits on its production cross section are determined for a Higgs boson of mass between 130 and 600 GeV.
Yields of prompt and non-prompt J/ψ, as well as Υ(1S) mesons, are measured by the CMS experiment ... more Yields of prompt and non-prompt J/ψ, as well as Υ(1S) mesons, are measured by the CMS experiment via their µ + µ − decays in PbPb and pp collisions at √ s NN = 2.76 TeV for quarkonium rapidity |y| < 2.4. Differential cross sections and nuclear modification factors are reported as functions of y and transverse momentum p T , as well as collision centrality. For prompt J/ψ with relatively high p T (6.5 < p T < 30 GeV/c), a strong, centrality-dependent suppression is observed in PbPb collisions, compared to the yield in pp collisions scaled by the number of inelastic nucleon-nucleon collisions.
Search for the standard model Higgs boson in the H → ZZ → 2 2ν channel in pp collisions at √ s = ... more Search for the standard model Higgs boson in the H → ZZ → 2 2ν channel in pp collisions at √ s = 7 TeV
A new modeling methodology that enables represent the urban traffic system (UTS) dynamic entities... more A new modeling methodology that enables represent the urban traffic system (UTS) dynamic entities using a multi-agent event oriented approach is presented. The methodology uses an enhanced n-Level net system (n-LNS) formalism of Petri nets. The first level describes the traffic network and UTS static and dynamic information objects; the second level describes the general entity behavior (activity execution, decision-making, entity interaction); finally at third level, particular entity behavior (process, skills and activities) incorporating a decision-making mechanism is described. The suggested novel methodology presented in this paper enable integrating formally diverse UTS dynamic entities behaviors in an event and multi-agent oriented approach.
We have characterized a temperate phage (MM1) from a clinical isolate of the multiply antibiotic-... more We have characterized a temperate phage (MM1) from a clinical isolate of the multiply antibiotic-resistant Spanish/American 23F Streptococcus pneumoniae clone (Spain 23F -1 strain). The 40-kb double-stranded genome of MM1 has been isolated as a DNA-protein complex. The use of MM1 DNA as a probe revealed that the phage genome is integrated in the host chromosome. The host and phage attachment sites, attB and attP, respectively, have been determined. Nucleotide sequencing of the attachment sites identified a 15-bp core site (5-TTATA ATTCATCCGC-3) that has not been found in any bacterial genome described so far. Sequence information revealed the presence of an integrase gene (int), which represents the first identification of an integrase in the pneumococcal system. A 1.5-kb DNA fragment embracing attP and the int gene contained all of the genetic information needed for stable integration of a nonreplicative plasmid into the attB site of a pneumococcal strain. This vector will facilitate the introduction of foreign genes into the pneumococcal chromosome. Interestingly, DNAs highly similar to that of MM1 have been detected in several clinical pneumococcal isolates of different capsular types, suggesting a widespread distribution of these phages in relevant pathogenic strains.
In order to better understand the mechanisms of action of a monoclonal anti-CD4/BF5 antibody(mAb)... more In order to better understand the mechanisms of action of a monoclonal anti-CD4/BF5 antibody(mAb), cytokine secretions were studied in 14 multiple sclerosis (MS) patients treated in a phase 1 trial. Secretion patterns of IFNgamma, IL2, IL4, IL10 and TNFalpha by peripheral blood mononuclear cells were studied before (DO) and after (D30) the treatment. We decided to undertake this study because in a previous one we observed no variations in serum levels of TNFalpha, IFNgamma, IL1, IL6. Results showed significant reductions in IFNgamma, IL2 and TNFalpha secretions after treatment. The anti-CD4 mAb seemed to act on both Th1- and Th2-cells but with preferential action on Th1-cells. Results on Th2-cells were less obvious even though a significant decrease in IL10 was observed. There was no correlation between any of the immunological markers studied and disease activity. This study demonstrates that pharmacological modifications of the CD4 receptor can induce variations in several cytokine secretion levels. It also stresses the role played by Th1- and Th2-cells in the etiopathogenesis of MS.
Exposure of newborn rats to hyperoxia impairs alveolarization. Nitric oxide (NO) may prevent this... more Exposure of newborn rats to hyperoxia impairs alveolarization. Nitric oxide (NO) may prevent this evolution. Angiogenesis and factors involved in this process, but also other growth factors (GFs) involved in alveolar development, are likely potential therapeutic targets for NO. We studied the effects of the NO donor, [Z]-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)aminio]diazen-1-ium-1, 2-diolate, also termed DETANONOate (D-NO), on hyperoxia-induced changes in key regulatory factors of alveolar development in neonatal rats, and its possible preventive effect on the physiologic consequences of hyperoxia. Newborn rat pups were randomized at birth to hyperoxia (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 95% O2) or room air exposure for 6 or 10 d, while receiving D-NO or its diluent. On Day 6, several GFs and their receptors were studied at pre- and/or post-translational levels. Elastin transcript determination on Day 6, and elastin deposition in tissue and morphometric analysis of the lungs on Day 10, were also performed. Hyperoxia decreased the expression of vascular endothelial growth factor (VEGF) receptor (VEGFR) 2, fibroblast growth factor (FGF)-18, and FGF receptors (FGFRs) FGFR3 and FGFR4, increased mortality, and impaired alveolarization and capillary growth. D-NO treatment of hyperoxia-exposed pups restored the expression level of FGF18 and FGFR4, induced an increase of both VEGF mRNA and protein, enhanced elastin expression, and partially restored elastin deposition in alveolar walls. Although, under the present conditions, D-NO failed to prevent the physiologic consequences of hyperoxia in terms of survival and lung alveolarization, our findings demonstrate molecular effects of NO on GFs involved in alveolar development that may have contributed to the protective effects previously reported for NO.
Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte... more Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte influx in airspaces, and impaired alveolarization. Inhibitors of type 4 phosphodiesterases are potent anti-inflammatory drugs now proposed for lung disorders. The current study was undertaken to determine the effects of the prototypal phosphodiesterase-4 inhibitor rolipram on alveolar development and on hyperoxia-induced lung injury.
Capnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reporte... more Capnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported.
Odile Launay, groupe hospitalier Cochin-Broca-Hôtel-Dieu, centre d'investigation clinique de vacc... more Odile Launay, groupe hospitalier Cochin-Broca-Hôtel-Dieu, centre d'investigation clinique de vaccinologie Cochin-Pasteur, 27, rue du Faubourg Saint-Jacques,
To assess neonatal morbidity in twin pregnancy according to the planned mode of delivery. A retro... more To assess neonatal morbidity in twin pregnancy according to the planned mode of delivery. A retrospective cohort study of 758 consecutive sets of twins born after 35 weeks of gestation with a cephalic-presenting first twin was undertaken in a level III maternity unit in which active management of the second twin delivery is performed routinely. The primary outcome was a composite measure of neonatal mortality and morbidity, including pH less than 7.0, 5-minute Apgar score less than 4, neonatal intensive care unit transfer more than 4 days, pneumothorax, and fracture. Control for potential confounders was performed by excluding from the analysis women who experienced pregnancy complications and by using logistic regression models. Vaginal or cesarean delivery was planned for 657 (86.7%) and 101 (13.3%) women, respectively. Among planned vaginal deliveries, 515 (78.4%) patients delivered both twins vaginally, 139 (21.1%) had a cesarean delivery during labor, and 3 (0.5%) had cesarean delivery for the second twin. After vaginal birth of the first twin, the mean intertwin delivery interval was 4.9+/-3.2 minutes. When patients who experienced pregnancy complications were excluded (n=202), the neonatal composite morbidity for the second twin did not differ between planned cesarean and planned vaginal delivery (5.0% compared with 4.7%, adjusted odds ratio 1.5, 95% confidence interval 0.3-7.4, P=.63). Neonatal composite morbidity of first twins did not differ between groups. For twin gestations with a cephalic-presenting first twin, planned vaginal delivery after 35 weeks of gestation in selected women remains a safe option in centers used to active management of the second twin delivery.
Clin Microbiol Infect 2010; 16: 1539–1543Clin Microbiol Infect 2010; 16: 1539–1543AbstractCapnocy... more Clin Microbiol Infect 2010; 16: 1539–1543Clin Microbiol Infect 2010; 16: 1539–1543AbstractCapnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported.Capnocytophaga, a genus of Gram-negative anaerobes that inhabit the oral cavity, has been reported to be an unusual cause of chorioamnionitis and neonatal infection. We report five cases of Capnocytophaga spp. infections in preterm infants (one proven infection and four probable infections) and review 14 previously reported cases. We suggest that Capnocytophaga sp. may be responsible for some occult causes of chorioamnionitis or preterm birth, and that the prevalence of this infection may be higher than previously reported.
Les apnées du prématuré constituent encore actuellement un problème clinique majeur, imposant des... more Les apnées du prématuré constituent encore actuellement un problème clinique majeur, imposant des choix thérapeutiques parfois difficiles. Des apnées plus ou moins longues surviennent chez presque tous les grands prématurés, témoignant d'une instabilité de la régulation respiratoire en rapport avec l'immaturité. Au rôle causal de celle-ci peut toutefois s'ajouter celui de nombreuses pathologies néonatales, qui peuvent aussi contribuer à la survenue d'apnées et doivent être recherchées et traitées. Les apnées du prématuré de courte durée (moins de dix secondes, sans hypoxémie ou bradycardie associée) peuvent être considérées comme sans risque pour l'enfant. Les apnées plus longues entraînent une hypoxémie et un ralentissement de la fréquence cardiaque et des perturbations de l'hémodynamique et de l'oxygénation cérébrales, susceptibles d'entraîner des effets délétères pour le développement à long terme. L'évaluation de leur degré de gravité immédiate et de leurs risques à long terme demeure imprécise. Les décisions thérapeutiques ne peuvent s'appuyer que sur assez peu de données scientifiques. Le citrate de caféine est un traitement efficace des apnées du prématuré, largement utilisé depuis des décennies. Mais c'est seulement très récemment qu'une évaluation rigoureuse de ses bénéfices et de ses inconvénients a été menée. Elle a mis en évidence la faible toxicité du citrate de caféine, et des bénéfices inattendus chez les enfants traités : diminution de fréquence des dysplasies bronchopulmonaires, de la persistance du canal artériel, et, à 18 mois, diminution du taux d'infirmité motrice cérébrale. La pression expiratoire positive par voie nasale, traitement également efficace des apnées, peut être utilisée en cas d'échec ou d'insuffisance du traitement par caféine et en association avec lui. ß 2009 Publié par Elsevier Masson SAS.
Genetic characterization of non-K1 Escherichia coli strains isolated from a mother and her neonat... more Genetic characterization of non-K1 Escherichia coli strains isolated from a mother and her neonate allowed us to provide evidence of the maternal origin of a late-onset neonatal infection. The use of ante- and peripartum antimicrobial prophylaxis with amoxicillin may have promoted the vertical transmission of this amoxicillin-resistant E. coli from mother to newborn. It allowed us to clarify the natural history of the disease.
Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte... more Background: Prolonged neonatal exposure to hyperoxia is associated with high mortality, leukocyte influx in airspaces, and impaired alveolarization. Inhibitors of type 4 phosphodiesterases are potent anti-inflammatory drugs now proposed for lung disorders. The current study was undertaken to determine the effects of the prototypal phosphodiesterase-4 inhibitor rolipram on alveolar development and on hyperoxia-induced lung injury.
Background Monitoring CO2 levels in preterm infants receiving mechanical ventilation is designed ... more Background Monitoring CO2 levels in preterm infants receiving mechanical ventilation is designed to avoid the harmful consequences of hypocapnia or hypercapnia. Capnography is of questionable accuracy for monitoring PCO2 in preterm infants. Objectives To determine the accuracy of sidestream capnography in ventilated preterm infants by comparing end-tidal carbon dioxide (EtCO2) values to mixed venous carbon dioxide pressure (PvCO2) and to transcutaneous carbon dioxide pressure (TcPCO2). Methods Simultaneous recordings of EtCO2, TcPCO2 and PvCO2 in 37 ventilated preterm infants. The PvCO2–EtCO2 gradient was calculated. The Bland–Altman technique and the intra-class correlation coefficient (ICC) were used to assess agreement between methods. The area under the curve (AUC) was calculated. Results Ninety-nine EtCO2/PvCO2 pairs were studied from 37 preterm infants with a mean gestational age of 27.7 ± 1.9 weeks and a mean birth weight of 1,003 ± 331 g. The mean PvCO2–EtCO2 gradient was 11.2 ± 8.0 mmHg, and the ICC was 0.28. The mean PvCO2–TcPCO2 gradient was 0 ± 7.8 mmHg, and the ICC was 0.78. AUCs for EtCO2 and TcPCO2 were similar in detecting high or low PvCO2. Conclusion Despite an insufficient correlation between EtCO2 and PvCO2, capnography was able to detect low and high CO2 warning levels with a similar efficacy to that of TcPCO2, and may therefore be of clinical interest.
The application of multi-disciplinary automotive technologies to hybrid vehicles has resulted in ... more The application of multi-disciplinary automotive technologies to hybrid vehicles has resulted in the integration of alternative propulsion sources and drive-by-wire components for enhanced ground vehicle performance, fuel economy, and occupant safety. The integration of steer-by-wire systems in vehicles facilitates autonomous and semi-autonomous operations, better lateral vehicle behavior, an adjustable steering "feel," and elimination of problems arising due to potential engine cycling. In this paper, a continuous time-varying tracking controller is designed for the vehicle's position/orientation using a simplified vehicle description and reference model for tracking. The tracking error is globally, exponentially forced to a neighborhood of about zero by transforming the system into a flat input-state system and then fusing a filtered tracking error transformation with the dynamic oscillator design. Mathematical models are presented for a steerby-wire rack and pinion unit, vehicle chassis, and tire/road interface dynamics. Representative numerical results are discussed to demonstrate the vehicle's transient response for a prescribed trajectory profile.
Uploads
Papers by Emmanuel Lopez