The efficacy and safety of polymyxins compared with other antibiotics in <i>Acinectobacter baumannii</i> infection.

<p>The efficacy and safety of polymyxins compared with other antibiotics in <i>Acinectobacter baumannii</i> infection.</p

Efficacy and Safety of Polymyxins for the Treatment of <i>Acinectobacter baumannii</i> Infection: A Systematic Review and Meta-Analysis

<div><p>Background</p><p>Multi-drug resistance among <i>Acinetobacter baumannii</i> increases the need for polymyxins. We conducted a meta-analysis aimed to assess the efficacy and safety of polymyxins for the treatment of <i>Acinetobacter baumannii</i> infection.</p><p>Methods</p><p>We searched PUBMED, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), CNKI, Chinese Biomedical Literature Database up to November 1, 2013, to identify published studies, and we searched clinical trial registries to identify completed unpublished studies. Randomized controlled trials and cohort studies were considered for inclusion. Data were extracted on clinical response, microbiological response, mortality, length of stay and adverse events.</p><p>Results</p><p>12 controlled studies, comparing 677 patients, were included. Although clinical (odds ratio 1.421, 95% confidence interval 0.722–2.797) and microbiological (OR 1.416, 95% CI 0.369–5.425) response rates favored the polymyxins group, these differences were not significant. Treatment with polymyxins vs. controls did not affect hospital mortality (OR 0.506, 95% CI 0.101–2.536), lengths of hospital stay (standard mean difference −0.221, 95% CI 0.899–0.458) or nephrotoxicity (OR 1.192, 95% CI 0.436–3.261). The combination of polymyxins with other antibiotics achieved similar clinical response rates to its monotherapy regimen (OR 0.601, 95% CI 0.320–1.130).</p><p>Conclusions</p><p>Our results suggest that polymyxins may be as safe and as efficacious as standard antibiotics for the treatment of <i>A. baumannii</i> infection. There is no strong evidence that combination regimen of polymyxins is superior to monotherapy regimen.</p></div

The efficacy and safety of polymyxins monotherapy compared with combination treatment in <i>Acinectobacter baumannii</i> infection.

<p>The efficacy and safety of polymyxins monotherapy compared with combination treatment in <i>Acinectobacter baumannii</i> infection.</p

The funnel plot of clinical response rate when polymyxins were compared with other antibiotics in <i>Acinectobacter baumannii</i> infection.

<p>The funnel plot of clinical response rate when polymyxins were compared with other antibiotics in <i>Acinectobacter baumannii</i> infection.</p

Characteristics of Studies Included in Systematic Review and Meta-analysis.

<p>Abbreviation: RCT = randomized controlled trial; VAP = ventilator associated pneumonia; VAT = ventilator associated tracheobronchitis; BSI = bloodstream infection; RTI =  respiratory tract infection; SSII =  skin or soft issue infection; CRI = catheter-related infection; UTI = urinary tract infection; SSI = surgical site infection; CIAI = complicated intra-abdominal infection; HAP = healthcare associated pneumonia; MDRAB = multi-drug resistant <i>Acinetobater baumannii</i>; EDRAB = extensively drug-resistant <i>Acinetobater baumannii</i>; CRAB = carbapenem-resistant <i>Acinetobacter baumannii</i>; AB = <i>Acinetobater bauma.</i></p

Flow diagram of included studies.

<p>Flow diagram of included studies.</p

The length of stay in hospital of patients when polymyxins were compared with other antibiotics in <i>Acinectobacter baumannii</i> infection.

<p>The length of stay in hospital of patients when polymyxins were compared with other antibiotics in <i>Acinectobacter baumannii</i> infection.</p

Freestanding MOF-Derived Honeycomb-Shape Porous MnOC@CC as an Electrocatalyst for Reversible LiOH Chemistry in Li‑O₂ Batteries

In rechargeable Li-O2 batteries, the electrolyte and the electrode are prone to be attacked by aggressive intermediates (O2– and LiO2) and products (Li2O2), resulting in low energy efficiency. It has been reported that in the presence of water, the formation of low-activity LiOH is more stable for electrolyte and electrode, effectively reducing the production of parasitic products. However, the reversible formation and decomposition of LiOH catalyzed by solid catalysts is still a challenge. Here, a freestanding metal–organic framework (MOF)-derived honeycomb-shape porous MnOC@CC cathode was prepared for Li-O2 batteries by in situ growth of urchin-like Mn-MOFs on carbon cloth (CC) and carbonization. The battery with the MnOC@CC cathode exhibits an ultrahigh practical discharge specific capacity of 22,838 mAh g–1 at 200 mA g–1, high-rate capability, and more stable cycling, which is superior to the MnOC powder cathode. X-ray diffraction and Fourier transform infrared results identify that the discharge product of the batteries is LiOH rather than highly active Li2O2, and no parasitic products were found during operation. The MnOC@CC cathode can induce the formation of flower-like LiOH in the presence of water due to its unique porous structure and directional alignment of Mn–O centers. This work achieves the reversible formation and decomposition of LiOH in the presence of water, offering some insights into the practical application of semiopen Li-O2 batteries

Regulating the N‑Coordination Structure of Fe–Fe Dual Sites as the Electrocatalyst for the O₂ Reduction Reaction in Metal–Air Batteries

Iron–nitrogen coordinated catalysts are regarded as efficient catalysts for the oxygen (O2) reduction reaction (ORR), wherein the coordination environment of Fe sites is critical to the catalytic activity. Herein, we explored the effect of the nitrogen-coordination structure of dual-atomic Fe2 sites (i.e., Fe2-N6-C and Fe2-N4-C) on the performance of the ORR. The half-wave potential (E1/2) of Fe2-N6-C is 0.880 V vs RHE, outperforming that of the tetracoordinate Fe2-N4-C (0.851 V) and commercial Pt/C (0.850 V) in alkaline electrolytes. The Fe2-N6-C-based zinc–air battery delivers a maximum power density of (258.6 mW/cm2) and superior durability under 10 mA/cm2. Theoretical calculations unveil that the moieties of Fe2-N6 profits the d-electron rearrangement of the Fe2 sites. The electronic and geometrical structure of Fe2-N6 promotes the O2 molecules adsorbed on the Fe2 site and reduces the dissociation energy barrier of O2, benefiting fracture of O–O bonds and acceleration of the transformation of O2 to *OOH (the first step of the ORR process). Such exploration of modulating the local N-coordination environment of Fe2 dimers paves an in-depth insight to design and optimize dual-atomic catalysts

Enhancement of the Photoelectrochemical Performance of WO₃ Vertical Arrays Film for Solar Water Splitting by Gadolinium Doping

In this study, WO₃ nanoplates modified by doping with gadolinium (Gd) were synthesized by a hydrothermal method. The effect of the rare-earth element on the photoelectrochemical (PEC) performance of WO₃ one- or two-dimensional (2D) materials was examined. Scanning electron microscopy, transmission electron microscopy, and X-ray diffraction were employed to examine the crystal phase and morphology of the Gd-doped nanoplates thus prepared. Results of UV–vis spectroscopy, valence-band (VB) X-ray photoelectron spectroscopy, and Mott–Schottky analyses indicated that the conduction band and VB potentials of WO₃ shifted to negative values. Linear sweep voltammetry results indicated that the photocurrent density increased by 153% after modification by doping with Gd. In addition, the PEC properties of the WO₃ nanoplates obtained by the intensity-modulated photocurrent spectrum and incident photon-to-current conversion efficiency measurements indicated that modification by doping with Gd has a scintillating application in improving the PEC conversion properties of WO₃-based 2D materials