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Saint-Maur-des-Fossés, France

Varon E.,Center National Of Reference Des Pneumocoques | Cohen R.,University Paris Est Creteil | Cohen R.,Groupe de Pathologie infectieuse Pediatrique Societe | Cohen R.,Center Hospitalier Intercommunal Of Creteil | And 4 more authors.
Vaccine | Year: 2015

Background: Changes in serotype distribution have been induced after pneumococcal conjugate vaccines (PCV) implementation, and non-vaccine serotypes are now circulating. Among these latter serotypes, we aimed to distinguish those with high invasive disease potential before (2008-2009) and after PCV13 implementation (2012-2013). Methods: Invasive pneumococcal disease (IPD) serotypes isolated from children 6 to 24 months were compared with nasopharyngeal-colonizing serotypes in healthy children. To assess the invasive potential of a given serotype, odds ratios (ORs) were calculated. For each serotype, OR >1 indicated increased probability of association with IPD and OR <1 decreased probability. Results: In 2008/2009 and 2012/2013, 355 pneumococci were isolated from 1212 healthy children and from 569 IPD, including 166 meningitis, 114 pneumonia, and 289 other IPDs. In period 1, serotypes 7F, 3, 1, 24F, and 19A showed highly significant invasive disease potential whereas in period 2, only serotype 24F was associated with a significant high OR (6.6 [95% CI 2.6; 16.2]). Of note, for serotype 12F, OR could not be calculated because of no carrier recorded, however, if there had been a single 12F carrier, the OR would be among the highest, in period 2, 15.7 [95% 3.4; 73.0]). Only two serotypes appeared negatively associated with IPD, 11A and 23B in the period 2 as compared with nine in period 1. In the second period, pneumococcal penicillin non-susceptible isolates were mostly represented by serotypes 19A, 15A, 19F, 35B and 24F both in carriers and IPD. Only one strain was resistant to penicillin with MIC. =. 4. μg/ml (serotype 19A) during the first period. Conclusion: In children <2 years old, compared to the previous period, the number of serotypes having a high disease potential decreased after PCV13 implementation, only two non-vaccine serotypes, 24F and 12F, had high invasive disease potential. © 2015 The Authors.

« Toyota restructures; product-based instead of function-based | Main | Škoda showcases MQB-based plug-in hybrid VisionS concept at Geneva; production PHEV in 2019, followed by BEV » Mazda North American Operations released EPA-estimated fuel economy figures for its all-new 2016 Mazda CX-9. Certified at an EPA-estimated 22 mpg city/28 mpg highway/25 mpg combined, when equipped with front-wheel drive, the 2016 CX-9 achieves best-in-class (MY 2016 midsize, three-row, non-hybrid crossover SUVs for sale in the US) city and combined fuel economy ratings and class-leading highway fuel economy. The second-generation CX-9’s efficiency reflect a 32% improvement compared to its predecessor. (In Canada, NR Canada estimates of fuel consumption put the improvement at 35%.) Like Mazda’s entire lineup of 2016 cars and crossovers, the 2016 CX-9 has adopted efficient, lightweight SKYACTIV Technology. Similar to the 2016 MX-5 Miata with its 29% improvement in EPA-estimated fuel economy versus its predecessor, the CX-9 benefits from a significant weight reduction, yet it adds amenities and provides more agile handling dynamics and improved performance. At the heart of the 2016 CX-9 is its new SKYACTIV-G 2.5T engine, which produces the power of a V-6 engine without the fuel-efficiency penalty. SKYACTIV-G 2.5T is the first turbocharged engine in the SKYACTIV-G series. CX-9’s engine delivers 310 lb-ft (420 N·m) of torque—comparable with a naturally aspirated 4-liter gasoline engine—from just 2,000 rpm and 250 hp (186 kW) at 5,000 rpm using 93-octane gasoline (227 hp with 87-octane). It comes paired with a six-speed SKYACTIV-Drive automatic transmission. Traditionally, turbocharged engines have suffered from poor dynamic performance at low rpm, including turbo lag, and disappointing real-world fuel economy. SKYACTIV-G 2.5T overcomes these problems with the Dynamic Pressure Turbo, the first turbocharging system that can vary the degree of exhaust pulsation depending on engine speed, and a cooled exhaust gas recirculation (EGR) system that allows the engine to maintain the ideal air-fuel ratio (λ=1) over a wider output range. High compression ratio. Mazda engineers achieved a compression ratio 10.5:1, one of the highest for any turbocharged engine with an 89-mm bore size that can run on regular gasoline. Dynamic Pressure Turbo. SKYACTIV-G 2.5T is the first turbocharged engine with the ability to change the degree of exhaust pulsation depending on engine speed. At low rpm (below 1620 rpm), the volume of the exhaust ports is reduced by closing a series of valves located just before the turbine that drives the turbocharger. This reduces interference between exhaust pulses and maximizes the energy of each pulse to obtain a high turbine driving force. At higher rpm, there is sufficient energy in the exhaust flow and the valves open, allowing the turbine to be driven by a steady flow of exhaust gases as in a traditional turbocharger. Whereas existing variable turbochargers adjust the speed or direction of exhaust gas flowing into the turbine, Dynamic Pressure Turbo is a unique technology that varies the degree of exhaust pulsation. Further assisting CX-9 to maximize turbocharger efficiency is a 4-3-1 exhaust. With this setup, the exhaust from the middle two cylinders (2 and 3) is joined into a single port, while the exhausts from the outer cylinders (1 and 4) each have their own ports. These three ports come together at the entrance to the turbocharger’s exhaust side, where there is always one exhaust pulse arriving every 180 degrees of crankshaft rotation. Not only does this very compact manifold keeps the exhaust pulses separate for maximum energy extraction, it also harnesses each exhaust pulse to suck the residual exhaust from the adjacent ports. Cooled Exhaust Gas Recirculation (EGR). This system takes some of the inert exhaust gas that results from the combustion process and reduces its temperature by passing it through a cooler before introducing it back into the engine’s air intake. This lowers the temperature of combustion in the engine from approximately 500 ˚C (932 ˚F) to just over 100 ˚C (212 ˚F), preventing knocking, expanding the range in which the engine can maintain the ideal air-fuel ratio and reducing the need to retard ignition timing. SKYACTIV-G principals of efficient combustion. SKYACTIV-G 2.5T is based on the naturally aspirated SKYACTIV-G 2.5 and features the same bore, stroke and bore pitch. Parts of the fuel system, such as the fuel pump and fuel injection system are also shared, helping SKYACTIV-G 2.5T to achieve the efficient combustion for which SKYACTIV-G engines are known. Front-wheel drive is standard, and Mazda’s predictive i-ACTIV all-wheel drive is optionally available. i-ACTIV all-wheel drive sends power where it’s needed before the driver can sense a loss in traction by measuring road and vehicle conditions more than 200 times per second via 27 sensors. Due to its lightweight design, i-ACTIV all-wheel drive adds little mechanical friction. The 2016 Mazda CX-9 will go on sale in late spring 2016. Final packaging and pricing will be announced closer to its on-sale date.

Cohen R.,ACTIV | Cohen R.,Center Hospitalier Intercommunal Of Creteil | Raymond J.,University of Paris Descartes
Medecine Therapeutique Pediatrie | Year: 2012

Bacterial nosocomial infections in pediatric patients have neither the frequency nor the severity of those observed in adult medicine. However, this must be tempered by the frequency of viral infections and the increasing proportion of children infected /colonized by Enterobacteriaceae producing β-lactamases ESBLs (extended spectrum) or carbapenemases, sometimes of community origin. Some measures can be recommended: recognize the presence of bacteria, isolation of patients, strictly enforce hygiene, proscribe unnecessary antibiotic treatment, reduce the prescription of selecting antibiotics, and improve the training of prescribers.

Cohen R.,ACTIV | Bingen E.,University Paris Diderot | Levy C.,ACTIV | Thollot F.,AFPA Association francaise de pediatrie ambulatoire | And 3 more authors.
BMC Infectious Diseases | Year: 2012

Background: Several studies have investigated the impact of 7-valent pneumococcal conjugate vaccine (PCV7) on pneumococcal (Sp) and staphylococcal (Sa) nasopharyngeal (NP) carriage. Few have investigated the impact on Haemophilus influenzae (Hi) and Moraxella catarrhalis (Mc) carriage. We aimed to compare the NP carriage rates in young children with acute otitis media (AOM) before and after PCV7 implementation in France.Methods: Prior to PCV7 implementation, we performed 4 successive randomized trials with NP samples. These studies compared several antibiotic regimens for treating AOM in young children (6 to 30 months). After PCV7 implementation, to assess the impact of the vaccination program on NP flora, young children with AOM were enrolled in a prospective surveillance study. In each study, we obtained an NP sample to analyze the carriage rates of Sp, Hi, Mc and Sa and the factors influencing the carriage. Standardized history and physical examination findings were recorded; the methods used for NP swabs (sampling and cultures) were the same in all studies.Results: We enrolled 4,405 children (mean age 13.9 months, median 12.8). Among the 2,598 children enrolled after PCV7 implementation, 98.3% were vaccinated with PCV7. In comparing the pre- and post-PCV7 periods, we found a slight but non-significant decrease in carriage rates of pneumococcus (AOR = 0.85 [0.69;1.05]), H. influenzae (AOR = 0.89 [0.73;1.09]) and S. aureus (AOR = 0.92 [0.70;1.19]). By contrast, the carriage rate of M. catarrhalis increased slightly but not significantly between the 2 periods (AOR = 1.08 [0.95;1.2]). Among Sp carriers, the proportion of PCV7 vaccine types decreased from 66.6% to 10.7% (P < 0.001), penicillin intermediate-resistant strains increased from 30.3% to 43.4% (P < 0.001), and penicillin-resistant strains decreased greatly from 22.8% to 3.8% (P < 0.001). The proportion of Hi ß-lactamase-producing strains decreased from 38.6% to 17.1% (P < 0.001).Conclusion: The carriage rates of otopathogen species (Sp, Hi, Mc) and Sa did not significantly change in children with AOM after PCV7 implementation in France. However, we observed significant changes in carriage rates of PCV7 vaccine serotypes and penicillin non-susceptible Sp. © 2012 Cohen et al; licensee BioMed Central Ltd.

Cohen R.,CHI Creteil | Levy C.,ACTIV | Bonnet E.,Pfizer | Thollot F.,AFPA | And 5 more authors.
BMC Infectious Diseases | Year: 2011

Background: After the implementation of 7-valent pneumococcal conjugate vaccine (PCV7), in several countries, serotype 19A is now the serotype most frequently involved in pneumococcal diseases and carriage. To determine factors potentially related to 19A nasopharyngeal (NP) carriage we analyzed data from an ongoing prospective French national surveillance study of pneumococcal NP carriage in young children.Methods: NP swabs were obtained from children aged 6 to 24 months, either during routine check-ups with normal findings, or when they presented with acute otitis media (AOM). The swabs were sent for analysis to the French National Reference Centre for Pneumococci. Factors influencing pneumococcal carriage and carriage of penicillin non-susceptible (PNSP), 19A and PNS-19A were investigated by multivariate logistic regression.Results: From 2006 to 2009, 66 practitioners enrolled 3507 children (mean age 13.6 months), of whom, 98.3% of children had been vaccinated with PCV7 and 33.4% of children attended daycare centres (DCC). Serotype 19A was found in 10.4% of the overall population, 20.5% of S. pneumoniae carriers (n = 1780) and 40.8% of PNSP carriers (n = 799). Among 19A strains, 10.7% were penicillin-susceptible, 80% intermediate and 9.3% fully resistant. Logistic regression analysis showed that the main factors associated with PNSP carriage were AOM (OR = 3.09, 95% CI [2.39;3.98]), DCC (OR = 1.70, 95% CI [1.42;2.03]), and recent antibiotic use (OR = 1.24, 95% CI [1.05;1.47]. The main factors predictive of 19A carriage were recent antibiotic use (OR = 1.81, 95% CI [1.42;2.30]), AOM (OR = 1.67, 95% CI [1.11;2.49]), DCC (OR = 1.56, 95% CI [1.21;2.2] and young age, <12 months (OR = 1.51, 95% CI [1.16;1.97]).Conclusion: In a population of children aged from 6 to 24 months with a high rate of PCV7 vaccination coverage, we found that antibiotic exposure, DCC attendance and AOM were linked to 19A carriage. © 2011 Cohen et al; licensee BioMed Central Ltd.

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