4,061 research outputs found

    Geographical variation in antimicrobial use and multiresistant pathogens in Brazilian intensive care units: a nationwide study

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    Introduction: Geographical analyses of antibiotic use identify regions with the highest consumption and help design policies for strategic patient groups.Methodology: We conducted a cross-sectional study based on official data available in July 2022 from Brazilian Health Surveillance Agency (Anvisa). Antibiotics are reported as a defined daily dose (DDD) per 1,000 patient-days, and central line-associated bloodstream infection (CLABSI) is defined according to Anvisa criteria. We also considered multi-drug resistant (MDR) as the critical pathogens the World Health Organization listed. We measured antimicrobial use and CLABSI trends per ICU bed using the compound annual growth rate (CAGR). Results: we evaluated the regional variation in CLABSI by multidrug-resistant pathogens and the antimicrobial use in 1,836 hospital intensive care units (ICUs). In 2020, the leader in use in intensive care units (ICUs) in the North was piperacillin/tazobactam (DDD = 929.7) in the Northeast. Midwest and South were meropenem (DDD = 809.4 and DDD = 688.1, respectively), and Southeast was ceftriaxone (DDD = 751.1). The North has reduced polymyxin use (91.1%), and ciprofloxacin increased (439%) in the South. There was an increase in CLABSI by carbapenem-resistant Pseudomonas aeruginosa in the North region (CAGR = 120.5%). Otherwise, CLABSI by vancomycin-resistant Enterococcus faecium (VRE) increased in all regions except the North (CAGR =-62.2%), while that carbapenem-resistant Acinetobacter baumannii increased in the Midwest (CAGR = 27.3%). Conclusions: we found heterogeneity in antimicrobial use patterns and CLABSI etiology among Brazilian ICUs. Although Gram-negative bacilli were the primary responsible agent, we observed a notable increase trend of CLABSI by VRE

    Anisotropic crack propagation and deformation in dentin observed by four-dimensional X-ray nano-computed tomography

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    Understanding the cracking behaviour of biological composite materials is of practical importance. This paper presents the first study to track the interplay between crack initiation, microfracture and plastic deformation in three dimensions (3D) as a function of tubule and collagen fibril arrangement in elephant dentin using in situ X-ray nano-computed tomography (nano-CT). A nano-indenter with a conical tip has been used to incrementally indent three test-pieces oriented at 0Ā°, 45Ā° and 70Ā° to the long axis of the tubules (i.e. radial to the tusk). For the 0Ā° sample two significant cracks formed, one of which linked up with microcracks in the axial-radial plane of the tusk originating from the tubules and the other one occurred as a consequence of shear deformation at the tubules. The 70Ā° test-piece was able to bear the greatest loads despite many small cracks forming around the indenter. These were diverted by the microstructure and did not propagate significantly. The 45Ā° test-piece showed intermediate behaviour. In all cases strains obtained by digital volume correlation were well in excess of the yield strain (0.9%), indeed some plastic deformation could even be seen through bending of the tubules. The hoop strains around the conical indenter were anisotropic with the smallest strains correlating with the primary collagen orientation (axial to the tusk) and the largest strains aligned with the hoop direction of the tusk

    Transcatheter indirect mitral annuloplasty induces annular and left atrial remodelling in secondary mitral regurgitation

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    Aims Mitral annuloplasty using the Carillon Mitral Contour System (CMCS) reduces secondary mitral regurgitation (SMR) and leads to reverse left ventricular remodelling. The aim of this study was to evaluate the effect of the CMCS on the mitral valve annulus (MA) and left atrial volume (LAV). Methods and results We retrospectively evaluated the data of all patients treated with the CMCS at our centre. Using transthoracic echocardiography, MA diameters were assessed by measuring the anterolateral to posteromedial extend (ALPM) and the anterior to posterior (AP) dimensions, respectively. Also, LAV and left ventricular endā€diastolic volume (LVEDV) were assessed. Patients were examined at three time points: baseline, at 20ā€“60 days (30dFUP), and at 9ā€“15 months (1yFUP), using paired analysis. From July 2014 until March 2019, 75 cases of severe SMR were treated using CMCS. Cases in which other devices were used in combination (COMBO therapy, n = 35) or in which the device could not be implanted (implant failure, n = 3) were excluded, leaving 37 patients in the present analysis. Analysis at 30dFUP showed a significant reduction of 16% in the mean ALPM diameter (7.27 Ā± 5.40 mm) and 15% in the AP diameter (6.57 Ā± 5.33 mm). Analysis of LAV also showed a significant reduction of 21% (36.61 Ā± 82.67 mL), with no significant change in LVEDV. At 1yFUP, the reduction of both the mean ALPM diameter of 14% (6.24 Ā± 5.70 mm) and the mean AP diameter of 12% (5.46 Ā± 4.99 mm) remained significant and stable. The reduction in LAV was also maintained at 23% (37.03 Ā± 56.91 mL). LAV index was significantly reduced by 17% at 30dFUP (15.44 Ā± 40.98 mL/m2) and by 13% at 1yFUP (11.56 Ā± 31.87 mL/m2), respectively. LVEDV index showed no significant change at 30dFUP and a nonā€significant 10% reduction at 1yFUP (17.75 Ā± 58.79 mL/m2). Conclusions The CMCS successfully treats symptomatic SMR with a stable reduction of not only the AP diameter of the MA, but the current study also demonstrates an additional reduction of the ALPM dimension at both 30dFUP and 1yFUP. We have also shown for the first time that LAV and LAV index are significantly reduced at both 30dFUP and 1yFUP and a nonā€significant positive remodelling of the LVEDV. This positive left atrial remodelling has not been looked for and demonstrated in earlier randomized studies of CMCS

    Super-resolution far-field ghost imaging via compressive sampling

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    Much more image details can be resolved by improving the system's imaging resolution and enhancing the resolution beyond the system's Rayleigh diffraction limit is generally called super-resolution. By combining the sparse prior property of images with the ghost imaging method, we demonstrated experimentally that super-resolution imaging can be nonlocally achieved in the far field even without looking at the object. Physical explanation of super-resolution ghost imaging via compressive sampling and its potential applications are also discussed.Comment: 4pages,4figure

    The Rho family GEF FARP2 is activated by aPKC iota to control tight junction formation and polarity

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    The elaboration of polarity is central to organismal development and to the maintenance of functional epithelia. Among the controls determining polarity are the PAR proteins, PAR6, aPKCĪ¹ and PAR3, regulating both known and unknown effectors. Here, we identify FARP2 as a ā€˜RIPRā€™ motif-dependent partner and substrate of aPKCĪ¹ that is required for efficient polarisation and junction formation. Binding is conferred by a FERM/FA domainā€“kinase domain interaction and detachment promoted by aPKCĪ¹-dependent phosphorylation. FARP2 is shown to promote GTP loading of Cdc42, which is consistent with it being involved in upstream regulation of the polarising PAR6ā€“aPKCĪ¹ complex. However, we show that aPKCĪ¹ acts to promote the localised activity of FARP2 through phosphorylation. We conclude that this aPKCĪ¹āˆ’FARP2 complex formation acts as a positive feedback control to drive polarisation through aPKCĪ¹ and other Cdc42 effectors

    Wolbachia and DNA barcoding insects: patterns, potential and problems

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    Wolbachia is a genus of bacterial endosymbionts that impacts the breeding systems of their hosts. Wolbachia can confuse the patterns of mitochondrial variation, including DNA barcodes, because it influences the pathways through which mitochondria are inherited. We examined the extent to which these endosymbionts are detected in routine DNA barcoding, assessed their impact upon the insect sequence divergence and identification accuracy, and considered the variation present in Wolbachia COI. Using both standard PCR assays (Wolbachia surface coding protein ā€“ wsp), and bacterial COI fragments we found evidence of Wolbachia in insect total genomic extracts created for DNA barcoding library construction. When >2 million insect COI trace files were examined on the Barcode of Life Datasystem (BOLD) Wolbachia COI was present in 0.16% of the cases. It is possible to generate Wolbachia COI using standard insect primers; however, that amplicon was never confused with the COI of the host. Wolbachia alleles recovered were predominantly Supergroup A and were broadly distributed geographically and phylogenetically. We conclude that the presence of the Wolbachia DNA in total genomic extracts made from insects is unlikely to compromise the accuracy of the DNA barcode library; in fact, the ability to query this DNA library (the database and the extracts) for endosymbionts is one of the ancillary benefits of such a large scale endeavor ā€“ for which we provide several examples. It is our conclusion that regular assays for Wolbachia presence and type can, and should, be adopted by large scale insect barcoding initiatives. While COI is one of the five multi-locus sequence typing (MLST) genes used for categorizing Wolbachia, there is limited overlap with the eukaryotic DNA barcode region

    Abiotic conditions in cephalopod (Sepia officinalis) eggs: embryonic development at low pH and high pCO2

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    Low pO(2) values have been measured in the perivitelline fluids (PVF) of marine animal eggs on several occasions, especially towards the end of development, when embryonic oxygen consumption is at its peak and the egg case acts as a massive barrier to diffusion. Several authors have therefore suggested that oxygen availability is the key factor leading to hatching. However, there have been no measurements of PVF pCO(2) so far. This is surprising, as elevated pCO(2) could also constitute a major abiotic stressor for the developing embryo. As a first attempt to fill this gap in knowledge, we measured pO(2), pCO(2) and pH in the PVF of late cephalopod (Sepia officinalis) eggs. We found linear relationships between embryo wet mass and pO(2), pCO(2) and pH. pO(2) declined from > 12 kPa to less than 5 kPa, while pCO(2) increased from 0.13 to 0.41 kPa. In the absence of active accumulation of bicarbonate in the PVF, pH decreased from 7.7 to 7.2. Our study supports the idea that oxygen becomes limiting in cephalopod eggs towards the end of development; however, pCO(2) and pH shift to levels that have caused significant physiological disturbances in other marine ectothermic animals. Future research needs to address the physiological adaptations that enable the embryo to cope with the adverse abiotic conditions in their egg environment
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