Background:Our aim was to compare the accuracy of lung ultrasound (LUS) and standard chest x-ray (CXR) for diagnosing pneumonia in older patients with acute respiratory symptoms (dyspnea, cough, hemoptysis, and atypical chest pain) admitted to an acute-care geriatric ward.Methods:We enrolled 169 (80 M, 89 F) multimorbid patients aged 83.0 ± 9.2 years from January 1 to October 31, 2015. Each participant underwent CXR and bedside LUS within 6 hours from ward admission. LUS was performed by skilled clinicians, blinded to CXR results and clinical history. The final diagnosis (pneumonia vs no-pneumonia) was established by another clinician reviewing clinical and laboratory data independent of LUS results and possibly prescribing chest contrast-enhanced CT. Diagnostic parameters of CXR and LUS were compared with McNemar test on the whole cohort and after stratification for Rockwood Clinical Frailty Scale.Results:Diagnostic accuracy for pneumonia (96 patients) was significantly higher in LUS (0.90, 95% confidence interval [CI] 0.83–0.96) compared with CXR (0.67, 95%CI 0.60–0.74, P < 0.001). LUS had a better sensitivity (0.92, 95%CI 0.86–0.97 vs 0.47, 95%CI 0.37–0.57) and negative predictive value (0.95, 95% CI 0.83–0.96 vs 0.57, 95%CI 0.48–0.56). In those patients with frailty (n = 87 with Rockwood Clinical Frailty Scale ≥5), LUS maintained a high diagnostic accuracy, but CXR did not (P = 0.0003). Interobserver agreement for LUS, calculated in a subsample of 29 patients, was high (k = 0.90).Conclusions:In multimorbid patients admitted to an acute geriatric ward, LUS was more accurate than CXR for the diagnosis of pneumonia, particularly in those with frailty. A wider use of LUS should be implemented in this setting.

The prognostic value of quick Sepsis-related Organ Failure Assessment (qSOFA) score in geriatric patients is uncertain. We aimed to compare qSOFA vs. Systemic Inflammatory Response Syndrome (SIRS) criteria for mortality prediction in older multimorbid subjects, admitted for suspected sepsis in a geriatric ward. We prospectively enrolled 272 patients (aged 83.7 ± 7.4). At admission, qSOFA and SIRS scores were calculated. Mortality was assessed during hospital stay and three months after discharge. The predictive capacity of qSOFA and SIRS was assessed by calculating the Area Under the Receiver Operating Characteristic Curve (AUROC), through pairwise AUROC comparison, and multivariable logistic regression analysis. Both qSOFA and SIRS exhibited a poor prognostic performance (AUROCs 0.676, 95% CI 0.609–0.738, and 0.626, 95% CI 0.558–0.691 for in-hospital mortality; 0.684, 95% CI 0.614–0.748, and 0.596, 95% CI 0.558–0.691 for pooled three-month mortality, respectively). The predictive capacity of qSOFA showed no difference to that of SIRS for in-hospital mortality (difference between AUROCs 0.05, 95% CI −0.05 to 0.14, p = 0.31), but was superior for pooled three-month mortality (difference between AUROCs 0.09, 95% CI 0.01–0.17, p = 0.029). Multivariable logistic regression analysis, accounting for possible confounders, including frailty, showed that both scores were not associated with in-hospital mortality, although qSOFA, unlike SIRS, was associated with pooled three-month mortality. In conclusion, neither qSOFA nor SIRS at admission were strong predictors of mortality in a geriatric acute-care setting. Traditional geriatric measures of frailty may be more useful for predicting adverse outcomes in this setting.

By competing for the acquisition of essential nutrients, Helicobacter pylori has the unique ability to persist in the human stomach, also causing nutritional insufficiencies in the host. Although the H. pylori genome apparently encodes selenocysteine synthase (SelA, HP1513), a key pyridoxal phosphate (PLP)-dependent enzyme for the incorporation of selenium into bacterial proteins, nothing is known about the use of this essential element in protein synthesis by this pathogen. We analyzed the evolution of the complete machinery for incorporation of selenium into proteins and the selenoproteome of several H. pylori strains and related Epsilonproteobacteria. Our searches identified the presence of selenoproteins—including the previously unknown DUF466 family—in various Epsilonproteobacteria, but not in H. pylori. We found that a complete system for selenocysteine incorporation was present in the Helicobacteriaceae ancestor and has been recently lost before the split of Helicobacter acinonychis and H. pylori. Our results indicate that H. pylori, at variance with other gastric and enterohepatic Helicobacter, does not use selenocysteine in protein synthesis and does not use selenium for tRNA wobble base modification. However, selA has survived as a functional gene, having lost the domain for the binding of selenocysteine tRNA, but maintaining the ability to bind the PLP cofactor. The evolutionary modifications described for the SelA protein of H. pylori find parallels in other bacterial and archaeal species, suggesting that an alternative enzymatic function is hidden in many proteins annotated as selenocysteinyl-tRNA synthase.

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In cystic fibrosis (CF), the accumulation of viscous lung secretions rich in DNA and actin is a major cause of chronic inflammation and recurrent infections leading to airway obstruction. Mucolytic therapy based on recombinant human DNase1 reduces CF mucus viscosity and promotes airway clearance. However, the marked susceptibility to actin inhibition of this enzyme prompts the research of alternative treatments that could overcome this limitation. Within the human DNase repertoire, DNase1L2 is ideally suited for this purpose because it exhibits metal-dependent endonuclease activity on plasmid DNA in a broad range of pH with acidic optimum and is minimally inhibited by actin. When tested on CF artificial mucus enriched with actin, submicromolar concentrations of DNase1L2 reduces mucus viscosity by 50% in a few seconds. Inspection of superimposed model structures of DNase1 and DNase1L2 highlights differences at the actin-binding interface that justify the increased resistance of DNase1L2 toward actin inhibition. Furthermore, a PEGylated form of the enzyme with preserved enzymatic activity was obtained, showing interesting results in terms of activity. This work represents an effort toward the exploitation of natural DNase variants as promising alternatives to DNase1 for the treatment of CF lung disease.