Outer membrane vesicles (OMVs) that are released from Gram-negative pathogenic bacteria can serve as vehicles for the translocation of effectors involved in infectious processes. In this study we have investigated the role of OMVs of the Vibrio cholerae O1 El Tor A1552 strain in resistance to antimicrobial peptides (AMPs). To assess this potential role, we grew V. cholerae with sub-lethal concentrations of Polymyxin B (PmB) or the AMP LL-37 and analyzed the OMVs produced and their effects on AMP resistance. Our results show that growing V. cholerae in the presence of AMPs modifies the protein content of the OMVs. In the presence of PmB, bacteria release OMVs that are larger in size and contain a biofilm-associated extracellular matrix protein (Bap1). We demonstrated that Bap1 binds to the OmpT porin on the OMVs through the LDV domain of OmpT. In addition, OMVs from cultures incubated in presence of PmB also provide better protection for V. cholerae against LL-37 compared to OMVs from V. cholerae cultures grown without AMPs or in presence of LL-37. Using a bap1 mutant we showed that cross-resistance between PmB and LL-37 involved the Bap1 protein, whereby Bap1 on OMVs traps LL-37 with no subsequent degradation of the AMP.
Background:This study aimed to assess the accuracy of three-point compression ultrasonography (3PCUS) performed for the diagnosis of proximal deep-vein thrombosis (DVT) in Emergency Department (ED) compared with the results of duplex US (DUS) (whole-leg compression ultrasound).Materials and Methods:The current prospective cross-sectional study with diagnostic test assessment was conducted on adult patients who were referred to the ED of a general teaching hospital in Shiraz, southern part of Iran (September 2016–May 2017), suspected of lower-extremity DVT, using a convenience sampling. The results of 3PCUS performed by ED residents were compared with the results of DUS performed by the radiology residents, which was considered as a criterion standard.Results:A total of 240 patients were enrolled, with a mean (standard deviation) age of 59.46 (16.58). 3PCUS has a sensitivity and a specificity of 100% (95% confidence interval [CI], 96.55%–100%) and 93.33% (95% CI, 87.72%–96.91%), respectively, in comparison with DUS (whole-leg compression ultrasound). Negative predictive value and positive predictive value were 100% and 92.11% (95% CI, 86.12%–95.64%), respectively, with an accuracy of 96.25% (95% CI, 93%–98.27%).Conclusion:The results of this study showed that 3PCUS of the lower extremities with a portable US machine, performed by the ED's residents, can accurately identify the presence or absence of lower-extremity DVT.
Diagnostic and therapeutic interventions in children for traumatic brain injury, which is known as the most important complication in trauma, require special attention. This study aimed to evaluate the accuracy of point-of-care ultrasound (POCUS) in diagnosing skull fracture in children with closed head injury in comparison with computed tomography (CT) scan. The current prospective cross-sectional study was conducted on children (0–14 years old), who were referred to the emergency department of a general teaching hospital in Shiraz, southern Iran (January–March 2018), with close head injury and were suspected of bone fracture. The participants were selected using a convenience sampling. The results of POCUS performed by emergency medicine (EM) residents were compared with the results of CT scan, which was reported by radiologists and considered a gold standard. Then, diagnostic tests were calculated. A total of 168 children were enrolled, with the mean ± standard deviation age of 6.21 ± 3.99. The most affected areas in the skull were the frontal (34.5%) and occipital areas (33.3%). POCUS had a sensitivity and specificity of 81.8% (95%CI, 48.2–97.7%) and 100% (95%CI, 97.7–100%), respectively. Positive and negative predictive values were 100% and 98.7%, with an accuracy of 98.8% in comparison with CT scan in the diagnosis of skull fracture. Conclusion : The results showed that POCUS with a portable ultrasonography machine, performed by the EM’s physicians, have high diagnostic precision and can be considered a tool in the management of patients with closed head injury. What is Known: • Some studies have investigated the accuracy of ultrasound in diagnosing skull bone fractures in children with closed head injury, but before conducting this survey, no definite evidence recommended POCUS for skull fracture in children with closed head trauma in the ED. What is New: • POCUS with a portable ultrasonography machine, performed by the EM’s physicians, has high diagnostic precision and can be considered a tool in the management of patients with closed head injury.
The authors regret that the original published version of the above article containe errors on Figs. 1 and 2. In Fig. 1, the data original read, "Excluded (n=414)" should have been "Excluded (n=410)" and in Fig. 2, the y-axis of the image should have a legend of "Sensitivity". The correct figures are shown as follows:
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