11 research outputs found

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    The changing epidemiology of Acinetobacter spp. producing MA. carbapenemases causing bloodstream infections in Brazil: a BrasNet report

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    Made available in DSpace on 2019-09-12T16:53:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2015Merieux Research Grants - Institut MerieuxWe evaluated the epidemiology of Acinetobacter spp. recovered from patients diagnosed with bloodstream infections in 9 tertiary hospitals located in all Brazilian geographic regions between April and August 2014. Although OXA-23-producing Acinetobacter baumannii clones were disseminated in most hospitals, it was observed for the first time the spread of OXA-72 among clonally related A. baumannii isolated from distinct hospitals. Interestingly, Acinetobacter pittii was the most frequent species found in a Northern region hospital. Contrasting with the multisusceptible profile displayed by A. pittii isolates, the tetracyclines and polymyxins were the only antimicrobials active against all A. baumannii isolates. (C) 2015 Elsevier Inc. All rights reserved.[Vasconcelos, Ana Tereza R.] Lab Nacl Comp Cient LNCC MCTI, Petropolis, RJ, Brazil[Barth, Afonso L.; Zavascki, Alexandre P.] Univ Fed Rio Grande do Sul, Hosp Clin Porto Alegre, Lab Pesquisa Resistencia Bacteriana LABRESIS, Porto Alegre, RS, Brazil[Gales, Ana C.; Furtado, Guilherme H. C.; da Silva, Juliana O.; Correa, Luci; Cayo, Rodrigo; Martins, Willames M. B. S.] Univ Fed Sao Paulo UNIFESP, Disciplina Infectol, Dept Med, Sao Paulo, SP, Brazil[Levin, Anna S.; Rossi, Flavia; Silva, Mariama T.; Oliveira, Maura S.; Dalben, Mirian F.; Santos, Sania A.] Univ Sao Paulo, Inst Med Trop USP LIM 54, Dept Patol LIM 03, Hosp Clin,Fac Med, Sao Paulo, SP, Brazil[Lucarevschi, Bianca R.; Moreira, Marina] Universidade de Taubaté (Unitau) , Dept Med[Cabral, Blenda G.; Brasiliense, Danielle M.; Carneiro, Irna Carla R. S.; Lima, Karla V. B.; da Conceicao, Marilia L.] Fundacao Santa Casa Misericordia Para UFPA, Belem, Para, Brazil[Cabral, Blenda G.; Brasiliense, Danielle M.; Carneiro, Irna Carla R. S.; Lima, Karla V. B.; da Conceicao, Marilia L.] Inst Evandro Chagas SVS MS, Belem, Para, Brazil[Ribeiro, Julival; Guzman, Ricardo D.] Hosp Base, Brasilia, DF, Brazil[Correa, Luci; Martino, Marines D. V.] Hosp Israelita Albert Einstein HIAE, Sao Paulo, SP, Brazil[Correa, Luci; Martino, Marines D. V.] Fac Ciencias Med Santa Casa Sao Paulo, Sao Paulo, SP, Brazil[Britto, Maria H.; de Freitas, Manse R.; Morais, Rosangela] Univ Fed Rio Grande Norte UFRN, Ctr Patol Clin, Natal, RN, Brazi

    Effect of lung recruitment and titrated Positive End-Expiratory Pressure (PEEP) vs low PEEP on mortality in patients with acute respiratory distress syndrome - A randomized clinical trial

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    IMPORTANCE: The effects of recruitment maneuvers and positive end-expiratory pressure (PEEP) titration on clinical outcomes in patients with acute respiratory distress syndrome (ARDS) remain uncertain. OBJECTIVE: To determine if lung recruitment associated with PEEP titration according to the best respiratory-system compliance decreases 28-day mortality of patients with moderate to severe ARDS compared with a conventional low-PEEP strategy. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, randomized trial conducted at 120 intensive care units (ICUs) from 9 countries from November 17, 2011, through April 25, 2017, enrolling adults with moderate to severe ARDS. INTERVENTIONS: An experimental strategy with a lung recruitment maneuver and PEEP titration according to the best respiratory-system compliance (n = 501; experimental group) or a control strategy of low PEEP (n = 509). All patients received volume-assist control mode until weaning. MAIN OUTCOMES AND MEASURES: The primary outcome was all-cause mortality until 28 days. Secondary outcomes were length of ICU and hospital stay; ventilator-free days through day 28; pneumothorax requiring drainage within 7 days; barotrauma within 7 days; and ICU, in-hospital, and 6-month mortality. RESULTS: A total of 1010 patients (37.5% female; mean [SD] age, 50.9 [17.4] years) were enrolled and followed up. At 28 days, 277 of 501 patients (55.3%) in the experimental group and 251 of 509 patients (49.3%) in the control group had died (hazard ratio [HR], 1.20; 95% CI, 1.01 to 1.42; P = .041). Compared with the control group, the experimental group strategy increased 6-month mortality (65.3% vs 59.9%; HR, 1.18; 95% CI, 1.01 to 1.38; P = .04), decreased the number of mean ventilator-free days (5.3 vs 6.4; difference, −1.1; 95% CI, −2.1 to −0.1; P = .03), increased the risk of pneumothorax requiring drainage (3.2% vs 1.2%; difference, 2.0%; 95% CI, 0.0% to 4.0%; P = .03), and the risk of barotrauma (5.6% vs 1.6%; difference, 4.0%; 95% CI, 1.5% to 6.5%; P = .001). There were no significant differences in the length of ICU stay, length of hospital stay, ICU mortality, and in-hospital mortality. CONCLUSIONS AND RELEVANCE: In patients with moderate to severe ARDS, a strategy with lung recruitment and titrated PEEP compared with low PEEP increased 28-day all-cause mortality. These findings do not support the routine use of lung recruitment maneuver and PEEP titration in these patients. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01374022
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