Usutu virus growth in human cell lines: induction of and sensitivity to type I and III interferons.

The mechanisms of Usutu virus (USUV) pathogenesis are largely unknown. The aim of this study was to evaluate the sensitivity of USUV to interferon (IFN) and the capacity of USUV to stimulate IFN production. Initial experiments were conducted to characterize the susceptibility of human cell lines to USUV infection and to evaluate the single-growth cycle replication curve of USUV. Results indicate that USUV is able to infect a variety of human cell lines, completing the replication cycle in Hep-2 and Vero cells within 48 h. Pre-treatment of cells with types I and III IFNs significantly inhibited the replication of USUV. However, the inhibitory effects of IFNs were considerably less if IFN was added after viral infection had been initiated. Also, USUV weakly induced types I and III IFNs.

Molecular epidemiology and genetic diversity of human rhinovirus affecting hospitalized children in Rome.

Human rhinoviruses (HRV) have been re-classified into three species (A-C), but the recently discovered HRV-C strains are not fully characterized yet. This study aimed to undertake a molecular and epidemiological characterization of HRV strains infecting children hospitalized over one year in two large research hospitals in Rome. Nasal washings from single HRV infections were retrospectively subjected to phylogenetic analysis on two genomic regions: the central part of the 5'Untranslated Region (5'UTR) and the Viral Protein (VP) 4 gene with the 5' portion of the VP2 gene (VP4/2). Forty-five different strains were identified in 73 HRV-positive children: 55 % of the cases were HRV-A, 38 % HRV-C and only 7 % HRV-B. HRV-C cases were less frequent than HRV-A during summer months and more frequent in cases presenting wheezing with respect to HRV-A. Species distribution was similar with respect to patient age, and seasonality differed during summer months with fewer HRV-C than HRV-A cases. On admission, a significantly higher number of HRV-C cases presented with wheezing with respect to HRV-A. The inter- and intra-genotype variability in VP4/2 was higher than in 5'UTR; in particular, HRV-A patient VP4/2 sequences were highly divergent (8-14 %) at the nucleotide level from those of their reference strains, but VP4 amino acid sequence was highly conserved. In HRV-C isolates, the region preceding the initiator AUG, the amino acids involved in VP4 myristoylation, the VP4-VP2 cleavage site and the cis-acting replication element were highly conserved. Differently, VP4 amino acid conservation was significantly lower in HRV-C than in HRV-A strains, especially in the transiently exposed VP4 N-terminus. This study confirmed the high number of different HRV genotypes infecting hospitalized children over one year and reveals a greater than expected variability in HRV-C VP4 protein, potentially suggestive of differences in replication.

Efficacy and Renal Safety of Dapagliflozin in Patients with Type 2 Diabetes Mellitus Also Receiving Metformin: A Real-Life Experience.

INTRODUCTION: This study aimed at evaluating the efficacy and safety of dapagliflozin in patients with type 2 diabetes (T2D) who also received metformin in clinical practice in Italy. METHODS: This was a retrospective observational study and it included data from patients who received dapagliflozin 10 mg once daily in conjunction with metformin for 12 months (DAPA + MET). In those with inadequate glycemic control, insulin or glimepiride was added after 30 days (DAPA + MET + other glucose-lowering drugs). Efficacy assessments included glycosylated hemoglobin (HbA1c) levels at 6 and 12 months, as well as body mass index (BMI) and lipid parameters at 12 months. Safety was also assessed. RESULTS: Data on 66 patients were included. In both groups, HbA1c was significantly reduced at 6 and 12 months compared with baseline and significant reductions in HbA1c were observed at 12 months compared with 6 months. Over the 12-month treatment period, dapagliflozin significantly reduced BMI in both groups. No significant changes in lipid parameters were observed in either group and no detrimental effects on renal function were detected. CONCLUSIONS: Dapagliflozin is effective and safe in patients with T2D also receiving metformin. Glycemic control was already achieved with dapagliflozin + metformin, and add-on therapy was not associated with further improvements.

The effectiveness and durability of an early insulin pump therapy in children and adolescents with type 1 diabetes mellitus.

BACKGROUND: This study evaluated the predictors of effectiveness and durability of insulin pump therapy in children and adolescents who have initiated continuous subcutaneous insulin infusion (CSII) within 2 years after the diagnosis of type 1 diabetes mellitus (T1DM). SUBJECTS AND METHODS: The charts of individuals with T1DM using insulin pumps who were treated at our center were reviewed, including subjects with age at onset of <22 years, interval between onset and insulin pump commencement (interval onset-commencement) of <2 years, use of pumps of >1 year, and use of glucose sensors for <4 weeks/year. The primary end point was the mean glycosylated hemoglobin (HbA1c) value (MHbA1c) throughout the follow-up. RESULTS: From 684 patients treated with insulin pumps, 119 met the inclusion criteria, and 113 were selected for statistical analysis (60 females; age at diabetes onset, 8.9±5.6 years [mean±SD]; follow-up, 4.0±1.8 years; range, 1-8 years; baseline HbA1c, 9.3±1.8%). Only the interval onset-commencement was a linear predictor of the MHbA1c (P=0.01; R(2)=0.089). A significant reduction of the mean yearly HbA1c from baseline throughout all the follow-up was observed (P<0.001). Categorizing the sample into four quartiles on the basis of an increasing interval onset-commencement resulted in levels of MHbA1c significantly lower in the first and second quartiles in comparison with the fourth quartile (7.6±0.8% and 7.8±1.0%, respectively, versus 8.5±0.8%; P<0.001 and P=0.004, respectively). CONCLUSIONS: The present study suggests that early pump commencement in children and adolescents with T1DM provides lower and more durable HbA1c values than a late commencement. It is possible that an early pump commencement could prolong the honeymoon phase, but we cannot confirm or exclude this hypothesis because the lack of data about C-peptide levels during the follow-up.

Interferon lambda 1-3 expression in infants hospitalized for RSV or HRV associated bronchiolitis.

OBJECTIVES: The airway expression of type III interferons (IFNs) was evaluated in infants hospitalized for respiratory syncytial virus (RSV) or rhinovirus (HRV) bronchiolitis. As an additional objective we sought to determine whether a different expression of IFN lambda 1-3 was associated with different harboring viruses, the clinical course of bronchiolitis or with the levels of well established IFN stimulated genes (ISGs), such as mixovirus resistance A (MxA) and ISG56. METHODS: The analysis was undertaken in 118 infants with RSV or HRV bronchiolitis. Nasopharyngeal washes were collected for virological studies and molecular analysis of type III IFN responses. RESULTS: RSV elicited higher levels of IFN lambda subtypes when compared with HRV. A similar expression of type III IFN was found in RSVA or RSVB infected infants and in those infected with HRVA or HRVC viruses. Results also indicate that IFN lambda 1 and IFN lambda 2-3 levels were correlated with each other and with MxA and ISG56-mRNAs. In addition, a positive correlation exists between the IFN lambda1 levels and the clinical score index during RSV infection. In particular, higher IFN lambda 1 levels are associated to an increase of respiratory rate. CONCLUSIONS: These findings show that differences in the IFN lambda 1-3 levels in infants with RSV or HRV infections are present and that the expression of IFN lambda 1 correlates with the severity of RSV bronchiolitis.

Prognostic accuracy of continuous glucose monitoring in the prediction of diabetes mellitus in children with incidental hyperglycemia: receiver operating characteristic analysis.

AIM: The purpose of this study is to evaluate continuous glucose monitoring (CGM) in predicting diabetes mellitus in children with incident hyperglycemia (IH) and negativity for some insular autoantibodies. SUBJECTS AND METHODS: Thirty-one autoantibody-negative children who presented at our center with IH underwent a baseline assessment and were followed up for 23.8 months (range, 6-48 months). At the end of the follow-up, we compared the receiver operating characteristic (ROC) areas under the curve (AUCs) of metabolic markers from 17 children who developed diabetes (Group A; n=17) and 14 children who did not develop diabetes (Group B; n=14). RESULTS: Only two oral glucose tolerance test (OGTT)-derived markers and three CGM-derived markers showed a good prognostic performance, with ROC AUCs indicating significant results (P<0.0001) for the following markers: 2-h glucose, OGTT (0.813; 95% confidence interval [CI] 0.621-0.954); AUC glucose, OGTT (0.832; 95% CI 0.611-0.950); CGM glucose measurement peak (0.803; 95% CI 0.621-0.923); percentage of CGM glucose measurements inside the range 70-125 mg/dL (0.866; 95% CI 0.695-0.961); and percentage of CGM measurements ≥126 mg/dL (0.889; 95% CI 0.724-0.973). The combination of the OGTT-derived markers did not increase the predictive value, but the combination of CGM markers with each other or with the OGTT markers yielded higher ROC AUCs (ranging from 0.828 to 0.945). CONCLUSIONS: This is the first study showing that CGM is useful in predicting diabetes mellitus in children with IH.

Pandemic 2009 H1N1 influenza virus is resistant to the antiviral activity of several interferon alpha subtypes.

Interferons (IFNs) are critically important in the control of influenza A virus infections. To better understand the pathogenic characteristics of the pandemic 2009 H1N1 influenza virus (pH1N1) from an innate immunity viewpoint, we investigated whether in vitro pH1N1 is sensitive to the antiviral activity of IFN beta, leukocyte IFN alpha, and several IFN alpha subtypes in a human lung adenocarcinoma epithelial cell line under single-growth cycle conditions. The results showed that 50% inhibitory concentration values against pH1N1 for various type I IFN preparations were higher than those against the IFN-sensitive encephalomyocarditis virus. Leukocyte IFN alpha and IFN alpha 5, 7, 8, 10, 14, 17, and 21 subtypes also appeared to be less active against pH1N1 than the Puerto Rico/8/34 H1N1 human influenza strain A. Taken together, the results provide new insights into the contributions of the various IFN alpha subtypes toward the regulation of innate immunity against pH1N1.

In vitro sensitivity of human metapneumovirus to type I interferons.

Human metapneumovirus (hMPV) has been recognized as an important respiratory pathogen. Due to its relatively recent discovery, only limited information is available on the relationship between hMPV and type I interferons (IFN). This study was designed to determine whether in vitro hMPV is sensitive to the antiviral activity of IFN-ß, leukocyte IFN-α, and several IFN-α subtypes in a human Hep-2 cell line. The results showed that 50% inhibitory concentration values against hMPV for the various type I IFN preparations were significantly higher than those against the IFN-sensitive vesicular stomatitis virus, and some IFN-α subtypes appeared to be more active against hMPV than others, with IFN-α subtypes 5, 6, 8, and 10 being the most potent, and IFN-α2, 17, and 21 the least potent. The results show that hMPV grown in Hep-2 is partially resistant to the antiviral activity of type I IFNs. Additional studies are required to understand whether and to what extent the relatively low sensitivity of hMPV to IFNs influences the clinical outcomes of infected individuals.